Conference Abstracts

- Oral Session -

O-A1: Bio-mimic Complexes for Hydrogen Storage Using CO2 as a Carrier

Wan-Hui Wang, 1,2) Xiujuan Feng 1) and Ming Bao 1,2) 1) State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, 116023, China 2) School of Chemical Engineering, Dalian University of Technology, Panjin, 124221, China

Transformation of greenhouse gas CO2 to fuel has attracted much attention because its important contribution to CO2 elimination and development of sustainable energy system. Formic acid (FA) is an important product of CO2 transformation since it can be used in direct FA fuel cell. In addition, it is also a promising hydrogen carrier because it is nontoxic, biodegradable, and liquidus at room temperature. We have designed and synthesized a series of proton-responsive Ir complexes with hydroxyl substituted N,N-bidentate ligands for efficient catalytic interconversion 1,2 between CO2/H2 and formic acid. Herein, we report our recent studies on catalytic

CO2 hydrogenation and dehydrogenation of formic acid using novel bio-inspired complexes.3 We have developed proton-responsive Ru pincer complexes for efficient hydrogenation of CO2 to formic acid/formate in water. Pendant OH group was demonstrated to be crucial for H2 heterolytic cleavage and favorable for hydride formation. In addition, we have developed bio-mimic Ir complexes with pendant amine group for FA dehydrogenation. The mechanistic investigation suggests that pendent amine group can significantly promote hydrogen generation via proton shuttle.

Reference 1. Wang, W.-H.*; Himeda, Y.*; Muckerman, J. T.*; Manbeck, G. F.; Fujita, E.* Chem. Rev. 2015, 115, 12936. 2. Wang, W.-H.; Ertem, M. Z.; Xu, S.; Onishi, N.; Manaka, Y.; Suna, Y.; Kambayashi, H.; Muckerman, J. T.; Fujita, E.; Himeda, Y.* ACS Catal. 2015, 5, 5496. 3. Wang, W.-H; Wang, H.; Yang, Y.; Lai, X.; Li, Y.;* Wang, J.; Himeda, Y.; Bao, M.* ChemSusChem. 2020, 13, 5015.

O-A2: Ir(NHC)-Catalyzed Sustainable Transfer Hydrogenation of

CO2 Yeon-Joo Cheong, Hye-Young Jang* Department of Energy Systems Research, Ajou University, Suwon 16499, Korea

Transition metal-catalyzed transformation of CO2 to valuable chemicals has received great attention because the consumption of CO2 would reduce CO2 in the air, and the production of chemicals from CO2 would reduce the further consumption of fossil fuel-based carbon sources. In particular, the transfer hydrogenation of CO2 using biomass-derived glycerol has advantages such as sustainability, nontoxicity, and nonvolatility of hydrogen source (glycerol), no use of explosive H2 gas, and the usefulness of byproducts (lactic acid) generated from glycerol.

Recently reported transfer hydrogenation of CO2 in glycerol involves ruthenium and iridium-based catalysts modified with N-heterocyclic carbene (NHC). The NHC- modified transition metal catalysts exhibit high catalytic activity and stability under harsh reaction conditions (high temperature and the basic media). In this presentation, we present various iridium catalysts modified with biscarbene and triscarbene ligands and their catalytic activity in the transfer hydrogenation of CO2 in glycerol.

O C O Ir catalyst or formate (FA) + lactate (LA) glycerol K2CO3

Ir(biscarbene) catalyst Ir(triscarbene) catalyst

R R N N N N N R N N R N - Ir Ir PF6 N - L N - COD X PF6

R N N R N N N N N R Ir N L Ir N - N COD X - Ir(COD)I R PF6 1. Y.-J. Cheong, K. Sung, S. Park, J. Jung, H.-Y. Jang, ACS Sustainable Chem. Eng. 2020, 8, 6972-6978. 2. Y.-J. Cheong, K. Sung, J.-A. Kim, K. Kim, H.-Y.Jang, Eur. J. Inorg. Chem. 2020, 4064-4068. O-A3: Mechanistic Understanding of Tandem Reaction of CO2 Reduction and Ethane Aromatization over Zn/P-ZSM-5

Huahua Fan1, Xiaowa Nie1,*, Xinwen Guo1,* and Chunshan Song1,2,*

1State Key Laboratory of Fine Chemicals, PSU-DUT Joint Center for Energy Research, School of Chemical Engineering, Dalian University of Technology, Dalian, P.R. China

2Department of Chemistry, Faculty of Science, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, P.R. China

Conversion of abundant and inexpensive light alkanes to more valuable aromatics is more lucrative and has received extensive attention. Tandem reactions of CO2 reduction and dehydrogenation/aromatization of light alkanes are more efficient and environment-friendly, in which CO2 can assist the catalytic conversion of light alkanes and improve the selectivity of target aromatic products. Modified zeolite can catalyze the dehydrogenation and aromatization of light alkanes coupled with CO2 reduction. The Zn/P-ZSM-5 catalyst that directly converts CO2 and ethane into liquid aromatics with high conversion and selectivity has been developed. The cooperation of CO2 and Zn/P-ZSM-5 inhibits the loss of Zn and significantly suppresses the carbon deposition via CO2-assisted oxidative dehydrogenation/aromatization of ethane over Zn/P-ZSM- 5, therefore enhancing the stability of the catalyst. Reaction pathways of ethane dehydrogenation/aromatization over Zn/ZSM-5 and Zn/P-ZSM-5 are identified by performing density functional theory calculations on the interactions among Zn, P and CO2. P addition increases the barriers for methane formation in the process of ethane dehydrogenation/aromatization over Zn/P-ZSM-5, thus promoting aromatics formation. With Zn/P-ZSM-5, the presence of CO2 can eliminate molecular H2 and consume carbon precursors, suppressing undesired hydrogenolysis and improving the catalyst stability. This work provides fundamental insight into the roles of P and CO2 in promoting ethane dehydrogenation/aromatization to aromatics.

O-A6: Boosting light olefin selectivity in CO2 hydrogenation by adding Co to Fe catalysts within close proximity Fei Yuan1, Guanghui Zhang1, Jie Zhu1, Fanshu Ding1, Anfeng Zhang1, Xinwen Guo1,*, Chunshan Song1,2,* 1State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024 2Department of Chemistry, the Chinese University of Hong Kong, Shatin, Hong Kong E-mail: [email protected]; [email protected]

Fig. 1 The influence of the intimacy between Fe and Co sites on the catalytic performance of CO2 hydrogenation = Direct conversion of carbon dioxide (CO2) into lower olefins (C2-C4 ) is highly attractive as a sustainable production route for its great significance in greenhouse gas emission control and fossil fuel substitution. Fe-based catalysts have been extensively studied in CO2 hydrogenation, which usually show unsatisfactory selectivity toward lower olefins. Here we present a high-dispersion catalyst precursor = CoFe2O4 with Na (Na-CoFe2O4) that offers C2-C4 space time yield as high as 2.88 = -1 -1 μmolC2-C4 gcat s and olefin to paraffin ratio about 6 at CO2 conversion higher than 41%. High dispersion and the intimate contact between Fe and Co sites help inhibit the formation of methane, and favor a higher selectivity of C2+ hydrocarbons, especially lower olefins. The presence of Na further promotes chain growth and suppresses the direct hydrogenation of Fe-(CH2)n intermediates. A superior stability over 100 h was observed, demonstrating the promising potential of this catalyst for industrial applications. References [1] Yuan, F.; Zhang, G.; Zhu, J,; Ding, F.; Zhang, A.; Guo, X.; Song, C.; Guo, X.; Song, C. Catalysis Today, 2021, 371, 142

O-A7: CO2 hydrogenation to C2+ products over TiO2 supported catalysts Canio Scarfiello1,2,3, Katerina Soulantica2, Philippe Serp1, Doan Pham Minh3 1LCC, CNRS-UPR 8241, ENSIACET, Université de Toulouse, France 2LPCNO, Université de Toulouse, CNRS, INSA, UPS, Toulouse, France 3Université de Toulouse, IMT Mines Albi, UMR CNRS 5302, Centre RAPSODEE Albi, France

More than 99% of anthropogenic CO2 emissions come from fossil fuels, mainly for energy production [1]. Therefore, CO2 conversion to valuable products is a necessary step toward a sustainable development of our societies. While the hydrogenation to

C1 products (CO, CH4, CH3OH, etc.) is relatively well mastered, the production of C2+ molecules is still challenging [2]. The thermocatalytic CO2 hydrogenation to liquid hydrocarbons can be achieved via methanol reaction mechanism [2] or via CO2 modified FTS mechanism [2]. The latter requires two reactions in series: the reverse water gas shift reaction (RWGS) for the initial hydrogenation of CO2 to CO; followed by the Fischer Tropsch synthesis (FTS) for the conversion of CO to C2+. Low temperatures are necessary to favor the exothermic FTS reaction and drive the selectivity towards C2-C4 and C5+ products. However, low temperatures favor methanation (exothermic) and are detrimental to RWGS (endothermic), leading to a series of competitive reactions that can strongly affect the selectivity of the global process. Thus, the main objective of this work is to design a convenient catalyst system which allows performing both steps of CO2 hydrogenation in to C2+ in a fixed- bed reactor. The targeted catalyst system is based on Pd and Co supported on commercial and modified TiO2 supports. The catalysts prepared on an appropriately modified support showed higher activity than those prepared on the commercial support, at temperatures as low as 220 and 250 °C. Moreover, different operating conditions allow modifying the product selectivity toward CO, CH4, C2-C4 and C5+. Under selected conditions, the selectivity to C5+ can be maintained above 50%.

[1] IEA, "Global Energy and CO2 Status Report," 2019.

[2] Ye, RP., Ding, J., Gong, W. et al. CO2 hydrogenation to high-value products via heterogeneous catalysis. Nat Commun 10, 5698 (2019). O-A8: An efficient semi-continuous process for the production of cyclic carbonates directly from CO2 and diols: A boost brought by a

biphasic (CO2+IL) reaction mixture

Yegor Borovkova , Ana B. Paninho a, Malgorzata E. Zakrzewska a,b, Ines Matosa, Zeljko Petrovskia, M. Fátima C. Guedes da Silvab, Ana V. M. Nunesa* aLAQV-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal bCentro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049–001 Lisbon, Portugal

CO2 utilization as a renewable carbon source in the production of cyclic carbonates is a very active field of research [1], with the most straightforward route consisting of a cycloaddition reaction between CO2 and epoxides [2]. However, epoxides are expensive and also have to be synthesized and isolated by energy demanding processes. An interesting alternative is the direct reaction between CO2 and alcohols, which could significantly increase the number of usable substrates, namely bio-based ones in the production of new sustainable carbonates totally derived from renewable resources [3]. However, this latter reaction is equilibrium limited and the resulting water has to be removed from the process to achieve reasonable conversions. Most methods reported in the literature are based on the utilization of expensive dehydrating agents which, aditionally, have to be used in large excess thus spoiling the sustainability of the process [4]. In this work, a semi-continuous process was developed exploring a biphasic reaction mixture composed of CO2 and a highly hydrophobic ionic liquid that continuously removes the water being formed. The strategy was applied using 1,2-butanediol as model substrate. Reactions were performed at different temperatures (80ºC-150ºC) and pressures (6-12 MPa) and the final products were quantitatively analysed by 1H-NMR spectroscopy. The biphasic system under study allowed to achieve surprisingly high reaction yields. The influence of experimental conditions on the reaction outcome will be presented and discussed. References: [1] M. North, R. Pasquale, C. Young, Green Chem 2010, 12, 1514-1539; [2] C.A. Montoya, C.F. Gomez, A.B. Paninho, A.V.M. Nunes, K.T. Mahmudov, V. Najdanovic-Visak, L. Martins, M. da Silva, A.J.L. Pombeiro, M. Nunes da Ponte, J.Catal. 2016, 335, 135-140; [3] L. P. Ozorio, C. J. A. Mota, ChemPhysChem 2017, 18, 3260; [4] N. Kindermann, T. Jose, A.W. Kleij,Top Curr Chem 2017, 375,15.Acknowledgements: This work was supported by Fundação para a Ciência e Tecnologia FCT/MCTES through project PTDC/EQU- EPQ/31926/2017, by the Associate Laboratory for Green Chemistry - LAQV which is financed by national funds from FCT/MCTES (UIDB/50006/2020 and UIDP/50006/2020) and by Centro de Química Estrutural-CQE which is financed by national funds from FCT/MCTES (UIDB/00100/2020). Rede Nacional de RMN (PTNMR), supported by FCT/MCTES through ROTEIRO/0031/2013 - PINFRA/22161/2016 and co-financed by FEDER through COMPETE 2020, POCI, and PORL and FCT/MCTES through PIDDAC. O-A9: Direct carboxylation of ethylene glycol coupled to pervaporation membranes for water removal Francesco Nocito, a,b Domenico Linsalata, b,c Michele Aresta, b,c Angela Dibenedettoa,b,c* aDepartment of Chemistry, University of Bari “Aldo Moro”, Via E. Orabona, 4, 70126, Bari, IT; bInteruniversity Consortium Chemical Reactivity and Catalysis, CIRCC, Via Celso Ulpiani, 27, 70126 Bari, IT; c IC2R srl, c/o Tecnopolis, 70018, Valenzano (BA), IT

The transition from the linear to the circular economy, when the Carbon Cyclic Economy-

CCE is considered, moves up CO2 reputation from waste to resource as either building block for chemicals or source of carbon for fuels.[1] This work aims to investigate the direct carboxylation of ethylene glycol (Eq. 1) over CeO2-based catalysts coupled to using inorganic pervaporation membranes for water elimination. [2]

After introducing the reaction’s thermodynamics, the efficiency of a number of CeO2- based catalysts [3] will be described, when used in batch conditions. The reaction parameter space will be illustrated and how they concur to achieve the best conversion yield. Side reactions will be shown that contribute to increase the water production, affecting the carboxylation equilibrium. By-products will be described as characterized by GC-MS. The effect of coupling with pervaporation membranes to remove water from the reaction mixture will be illustrated in both batch and flow reaction conditions.

Acknowledgements

IC2R srl, CIRCC and the PRIN Project “CO2 only”-2017WR2LRS are acknowledged for funding.

References [1] M. Aresta and A. Dibenedetto, The Carbon Dioxide Revolution. Springer International Publishing, 2021. [2] M. Aresta and A. Dibenedetto, Frontiers in Energy Research, 2020, 8, 159. [3] A. Dibenedetto, M. Aresta, A. Angelini, J. Ethiraj, and B. M. Aresta, Chemistry – A European Journal, 2012, 18, 33, 10324–10334.

O-A10: Robust pyrrole-containing Zinc complexes for the catalytic valorisation of CO2 into cyclic carbonates

Lorraine Christ, Miguel Alonso de la Peña, Alain Tuel, Université de Lyon, IRCELYON, UMR CNRS 5256, Villeurbanne, France

The reaction of CO2 and epoxides to form organic carbonates requires Lewis base catalysts, such as tetrabutylammonium halides (TBAX). Their activity and selectivity towards cyclic carbonates can be strongly reinforced with Lewis acids, as for example, Salen or porphyrin metallic complexes. We developed a series of nitrogen Schiff base (N-

SB) compounds1 that forms a family of ligands that combines properties of both, Salen flexibility and porphyrins nitrogen coordination sphere. Herein, we present the synthesis and characterization of pyrrole containing Nitrogen-Schiff Base (N-SB) ligands. XRay analysis showed monomeric or dimeric helical structures, according with the coordination mode of the zinc centre that can be tetra or pentacoordinated. Combined to TBAX, the zinc N-SB complexes proved to be efficient and selective co-catalysts for the valorisation of CO2 into cyclic carbonates. The optimization of the reaction parameters was carried out with styrene oxide, and solvent free reactions allowed very high yields (up to 97%) using very small catalyst/co-catalyt amounts (less than 0.2mol%)2. Moreover, the robustness of these zinc complexes allowed various catalytic runs four days long, without any purification, just adding new loadings of styrene oxide. The reaction scope was also enlarged to other epoxides.

1. I. Karamé, L. Tommasino (Christ) et al. Tetrahedron: Asymmetry 15(2004) 1569-1581 2. M. Alonso, L. Merzoud, W. Lamine, A. Tuel, H. Chermette, L. Christ, J.CO2 U., 44 (2021)101380 O-A11: Yellow TiO2-CuO Core-shell Nanoparticles for

Photosynthesis of Cyclic Carbonates using CO2

Jeannie Z. Y. Tan; M. Mercedes Maroto-Valer

Research Centre for Carbon Solutions, Heriot-Watt University, Edinburgh, United Kingdom.

The utilisation of CO2 to produce fuels, chemicals and plastics has offered an attractive alternative to mitigate the increase of CO2 emissions and the associated global warming issues. Cyclic carbonates, which are essential compounds in the industry due to their applications as polymer precursors, fuel additives or electrolytes in batteries, and their uses as aprotic high-boiling point solvents,1 The production of cyclic carbonates from CO2 driven by solar energy could be a highly profitable reaction while using less energy compared to the state-of-the-art high temperature and pressure manufacturing process.2 In addition, heterogeneous photocatalytic synthesis of cyclic carbonates presents several advantages over homogeneous photocatalysis, including easier recovery of the photocatalyst. Therefore, the photocatalytic conversion of epoxide and CO2 into cyclic carbonates requires an efficient heterogeneous photocatalyst and the use of core-shell nanostructured photocatalyst is proposed. The close interaction between the core and shell yellow TiO2 and CuO is important to minimise the recombination of photogenerated electron-hole pair through the formation of p-n junctions within the particles. The thickness of shell CuO is controlled to optimise the photoconversion of epoxide and CO2 into cyclic carbonates under simulated sunlight, whereas he as-prepared CuO and yellow TiO2 photocatalysts produced insignificant amounts of product, indicating the importance of the composite core-shell photocatalyst for the photosynthesis of cyclic carbonates. The products produced from the reaction were analysed using NMR and revealed 1.8% of conversion efficiency and 100% selectivity towards cyclic carbonates after 6 hours.

References: 1. R. Vicente and S. Mata, in Advances in Transition-Metal Mediated Heterocyclic Synthesis, eds. D. Solé and I. Fernández, Academic Press, 2018, DOI: https://doi.org/10.1016/B978-0-12-811651-7.00007-8, pp. 285-310. 2. M. North, R. Pasquale and C. Young, Green Chem., 2010, 12, 1514-1539. O-A12: Impact of Solvent in the Hydrogenation of Carbon Dioxide Using Molecular Complexes

Aaron M. Appel, John C. Linehan, Eric S. Wiedner

Institute for Integrated Catalysis, Pacific Northwest National Laboratory, Richland, WA, USA

The widespread and efficient use of carbon-neutral energy will be facilitated by the storage of this energy in the form of high energy density fuels. The utilization of inexpensive substrates such as CO2 provides an opportunity for large-scale energy storage, and in particular, CO2 can potentially be converted to liquid fuels for use in transportation. To effectively and efficiently interconvert energy and fuels, catalysts are required for these multistep transformations. By understanding the free energies for the transfer of H+, H•, and H– from M–H and analogous species, our research group seeks to rationally design molecular catalysts for the interconversion of energy and fuels. For the hydrogenation of CO2, the solvent has a substantial impact on the free energy for transfer of a hydride from a metal complex to CO2. Through recent studies, we have demonstrated that new catalyst systems can be designed through variation of solvent composition, rather than purely through synthetic modification. The impact of solvent composition on hydride transfer as well as catalytic activity will be presented.

This research was supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences.

O-A13: CO2 hydrogenation to higher hydrocarbons assisted by non-thermal plasma Xiaoxing Wang1*, Jiajie Wang1,6, Mohammad S. AlQahtani1,2, Sean D. Knecht3, Sven G. Bilén3,4, Chunshan Song1,2.5*, and Wei Chu6

1Clean Fuels & Catalysis Program, EMS Energy Institute, Department of Energy and Mineral Engineering, 2Department of Chemical Engineering, 3School of Engineering Design, Technology, and Professional Programs, 4School of Electrical Engineering and Computer Science, The Pennsylvania State University, University Park, PA, 16802, USA. 5Department of Chemistry, Faculty of Science, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China. 6Department of Chemical Engineering, Sichuan University, Sichuan, P.R. China, *Email: [email protected]; [email protected]; [email protected]

Ever-increasing emission of CO2, which is a main contributor to global climate change, has aroused great concerns worldwide. Effectively converting CO2 into fuels and value-added chemicals represents an important approach for mitigating carbon emissions, yet remains a challenge in catalysis due to the high thermal stablity of the

CO2 molecule. Non-thermal plasma (NTP), consisting of highly energetic electrons (1– 10 eV) and reactive species (i.e., ions, radicals, excited atoms, and excited molecules), provides a unique medium to enable thermodynamically and/or kinetically unfavored reactions at low temperatures. Here, we report on a highly effective process + for catalytic CO2 hydrogenation to C2 hydrocarbons with the assistance of dielectric barrier discharge (DBD) NTP at low temperature and atmospheric pressure. Plasma alone can convert CO2, but mainly to CO (over 80% selectivity). With catalyst, the main + + product shifts to CH4, along with trace amounts of C2 hydrocarbons. Interestingly, C2 hydrocarbons selectivity can be dramatically enhanced by simply changing the catalyst-bed configuration under plasma. At operating temperature of 25 °C and 10-W + DBD plasma, 46% C2 hydrocarbons selectivity was achieved at CO2 conversion of + 74%. The significance of catalyst-bed configuration and possible origin of C2 formation are studied and discussed. The present work may broaden the utilization of the plasma–catalyst synergy for effective catalytic CO2 utilization.

O-A14: Structural evolution of well-defined catalysts during CO2 hydrogenation Guanghui Zhang1, Xinbao Zhang1, Jianyang Wang1, Jie Zhu1, Xinwen Guo1,*, Chunshan Song1,2,* 1State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024 2Department of Chemistry, the Chinese University of Hong Kong, Shatin, Hong Kong E-mail: [email protected]; [email protected]

Understanding the structure-property relationship of catalysts is critical for designing new ones with better performance. However, catalysts are inherently dynamic in nature, as they respond to the environment by changing their local and extended structures. Two examples will be given to showcase our work in understanding the dynamic nature of the catalytic surfaces, specifically in the hydrogenation reaction of carbon dioxide. In the first example, we show that the activity of h-In2O3 increases gradually with time on stream in the reverse water gas shift reaction, which is caused by a phase transition from h-In2O3 to c-In2O3. In situ X-ray diffraction results show that h-In2O3 is first reduced by H2 and subsequently oxidized by CO2 to c-In2O3. In the second example, on a well-defined spinel ZnAl2O4 catalyst, the surface reconstruction leads to a core-shell structure of ZnO-rich shell and spinel core, which is accompanied by the increasing catalytic activity of methanol formation. We believe these two examples provide useful insight into the dynamic nature of the catalytic surfaces during CO2 hydrogenation.

References [1] Wang, J.; Liu, C.-Y.; Senftle, T.P.; Zhu, J.; Zhang, G.; Guo, X.; Song, C. ACS Catal. 2020, 10, 3264 [2] Wang, J.; Zhang, G.; Zhu, J.; Zhang, X.; Ding, F.; Zhang, A.; Guo, X.; Song, C. ACS Catal. 2021, 11, 1406 [3] Zhang, X.; Zhang, G.; Liu, W.; Yuan, F.; Wang, J.; Zhu, J.; Jiang, X.; Zhang, A.; Ding, F.; Song, C.; Guo, X. Appl. Catal. B: Environ. 2021, 284, 119700

O-A15: Exploring the Active Sites for Selective CO2 Hydrogenation over Supported Cobalt-Based Catalysts Mingrui Wang1, Guanghui Zhang1, Jie Zhu1, Jianyang Wang1, Kai Bian1, Wenhui Li1, Fanshu Ding1, Xinwen Guo1,*, Chunshan Song1,2,* 1State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024 2Department of Chemistry, the Chinese University of Hong Kong, Shatin, Hong Kong E-mail: [email protected]; [email protected]

Unraveling the correlation between the structure of active sites and reaction pathway is of utmost importance to tuning the product selectivity in CO2 hydrogenation over cobalt-based catalysts. In this study, the smaller cobalt species highly dispersed on SBA-15 supports were used to obtain more cobalt oxide sites under reaction conditions. We found that highly active CoO sites on SBA-15 are benefical for RWGS (reverse water gas shift) reaction, whereas metallic cobalt sites derived from large cobalt species on SiO2 support mainly promote CO2 methanation. Formate dominates on CoO sites and serves as the intermediate for CO formation, while more carboxylate 0 was observed on Co sites and further hydrogenated to CH4. Moreover, the structure evolution from CoO sites to Co0 sites with increasing temperature was monitored by in situ XRD, low temperature CO probe IR and XPS spectroscopy. We confirmed that the reduction is partly suppressed for small cobalt oxide over SBA-15, and the larger 0 Co metallic sites on catalyst surface perform better for CH4 formation. The scientific understanding about the structure of active cobalt sites and pathway in this work offers opportunities for optimizing selective CO2 hydrogenation to desired products over cobalt-based catalysts.

Fig. 1 Active metallic and oxidized sites over supported cobalt-based catalysts in CO2 hydrogenation References Li, W.; Zhang, G.; Jiang, X.; Liu, Y.; Zhu, J.; Ding, F.; Liu, Z.; Guo, X.; Song, C. ACS Catal. 2019, 9, 2739 O-A16: Integrated CO2 Capture and Reduction to Methane using Ni-

based Dual-Functional Catalysts toward Atmospheric CO2 Utilization

Fumihiko Kosaka1, Tomone Sasayama1, Yanyong Liu1, Shih-Yuan Chen1, Takehisa Mochizuki1, Atsushi Urakawa2, and Koji Kuramoto1 1Energy Process Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki Japan 2Department of Chemical Engineering, Delft University of Technology, 2629 HZ Delft, The Netherlands

Direct conversion of dilute CO2 from flue gases or atmosphere into hydrocarbons without CO2 purification is one of the awaited technologies in envisioned low-carbon societies by lowering energy and capital costs for CO2 purification, storage, and transportation. In this study, we investigated integrated CO2 capture and reduction performance into CH4 under various reaction conditions over Ni-based dual-functional catalysts. We prepared Ni/Na-Al2O3, Ni/K-Al2O3, Ni/Ca-Al2O3 as dual-functional catalysts, and Ni/Al2O3 as a reference with impregnation method, and conducted CO2 capture and hydrogenation cycles in a fixed bed reactor. Cycles of (i) CO2 capture from dilute CO2 (100 ppm–5% CO2), (ii) N2 purge, and (iii) reduction of the chemically captured CO2 in the catalysts with H2 were conducted.

For 5% CO2 capture and reduction, Ni/Na-Al2O3 showed the highest performance with high CO2 conversion (>96%) and CH4 selectivity (>93%). In addition, very low CO2 levels of 100 ppm were successfully converted to 11.5% CH4 at a peak point over Ni/Na-Al2O3, which was more than 1000 times higher concentration than that of the supplied CO2. Furthermore, the Ni/Na-Al2O3 successfully captured 400ppm

CO2 in the presence of O2 and converted it into CH4 with high CO2 conversion (>90%).

The effect of pressurized conditions was also investigated, and both CO2 capture capacity and CH4 formation efficiency were improved with increasing pressures. As the pressure increased from 0.1 to 0.9 MPa, CH4 production with 400 ppm CO2 capture was enhanced from 111 to 160 μmol g-1. These results suggest that efficient dual- functional catalysts are promising for CO2 utilization, thus enabling direct air capture- conversion to value-added chemicals. O-A17: Separation-enhanced CO2 conversion: Status and outlook Jurriaan Boon, Galina Skorikova, Jasper van Kampen, Marija Saric, Soraya N. Sluijter, Johannis A.Z. Pieterse Sustainable Technologies for Industrial Processes, TNO, Petten, The Netherlands

Conversion of CO2 with H2 into fuels and chemicals will play an essential role in the energy transition. Important examples include reactions (1-2):

CO2 + 3H2 ⇌ CH3OH + H2O direct methanol synthesis (1)

2CO2 + 6H2 ⇌ CH3OCH3 + 3H2O direct dimethyl ether (DME) synthesis (2) Produced water limits the conversion by thermodynamic equilibrium. Conversely, in situ removal of water allows to reach a near-complete conversion [1]. This contribution gives a perspective on separation enhanced CO2 conversions.

Sorption-enhanced DME synthesis: SEDMES A dynamic SEDMES cycle was experimentally validated with a pressure swing regeneration, achieving over 80% single-pass carbon selectivity from CO2 to DME [3].

Techno-economic analysis for DME synthesis from CO2 and green H2 indicated significant cost reduction compared to conventional processes. A containerised pilot is now constructed (TRL5-6) for further scale-up and onsite demonstration of SEDMES.

Enhanced-membrane methanol synthesis: EMM EMM is currently being validated in industrially relevant environment, using a novel developed polyimide membrane for water removal. The integrated reactor is set to achieve 33% conversion per pass on a CO2-H2 feed reducing the CAPEX by 10%.

Sorption-enhanced reverse water-gas shift, methanation, and hydrocarbons Recent advances on sorption-enhanced rWGS, methanation, olefins, and paraffins synthesis are discussed, focusing on promising concepts for separation-enhanced

CO2 conversion. References

1. Van Kampen, J., et al. (2019). Chem. Eng. J., 374, 1286-1303. 2. Walspurger, S., et al. (2014). Chem. Eng. J., 242, 379-386; Pieterse, J. A. Z. et al. (2021). Catal. Letters, in press, DOI 10.1007/s10562-021-03645-1. 3. Van Kampen, J., et al. (2020). Chem. Comm., 56(88), 13540-13542; Van Kampen, J., et al. (2021). Reaction Chemistry & Engineering., 6(2), 244-257. 4. Skorikova, G., et al. (2020). Frontiers in Chemical Engineering, 2, 594884 O-A18: Influence of Preparation Method on Structure, Reducibility

and Activity of Ni-based CO2 Methanation Catalysts K. L. Abel1, R. T. Zimmermann2, J. Titus1, D. Poppitz1, K. Sundmacher2, R. Gläser1 1 Institute of Chemical Technology, Leipzig University, Leipzig, Germany 2 Chair for Process Systems Engineering, Otto von Guericke University Magdeburg, Magdeburg, Germany

The activity and selectivity of CO2 methanation catalysts depends on the preparation method, which affects both dispersion and electronic structure of the active phase [1].

In this context, we study Ni/Al2O3 and Ni/SiO2-ZrO2 catalysts prepared by impregnation and co-gelation [2]. NiO formation and Ni incorporation into the Al2O3 framework occur at the same time during calcination (Fig. 1). While this results in high Ni dispersion, it also requires high reduction temperatures (Tred > 1100 K). Therefore, these catalyst types are not applicable for CO2 methanation, but rather for high-temperature conversions such as the methane dry reforming [2]. Thus, for CO2 methanation it is desirable to use an impregnation procedure instead. Below calcination temperatures of 973 K, this results in the formation of

NiO nanoparticles on the Al2O3 support

(Fig. 1) with a much lower Tred of

~823 K. Consequently, Ni/Al2O3 catalysts from impregnation exhibit a

higher catalytic activity in CO2

methanation with H2 when compared to catalysts from co-gelation. Similar

findings also apply to Ni/SiO2-ZrO2

Fig. 1: Powder XRD patterns of Ni/Al2O3 xerogels, xerogels. This indicates that for Ni prepared via impregnation (Imp.) or co-gelation catalysts on oxidic supports in general, (Cog.) at different calcination temperatures. co-gelation may readily lead to Ni incorporation into the support framework, while reactive NiO nanoparticles may be obtained by impregnation.

[1] J. Gao, Q. Liu, F. Gu, B. Liu, Z. Zhong, F. Su, RSC Adv. 5 (2015) 22759-22776. [2] S. Weber, K. L. Abel, R. T. Zimmermann, X. Huang, J. Bremer, L. Rihko-Struckmann, D. Batey, S. Cipiccia, J. Titus, D. Poppitz, C. Kübel, K. Sundmacher, R. Gläser, T. L. Sheppard, Catalysts 10 (2020) 1471. O-A21: Promotional effects of CeO2 on Pt-Sn/SiO2 for oxidative

dehydrogenation of propane with CO2 Li Wang, Guo-Qing Yang, Heng-Bo Zhang, Zhong-wen Liu* Key Laboratory of Syngas Conversion of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi’an 710062, China *e-mail: [email protected]

The oxidative dehydrogenation of propane with CO2 (CO2-ODP) is a sustainable route for producing propylene with the tandem conversion of CO2 to the value-added [1] CO . To date, the majority of the potential catalysts for CO2-ODP is originated from those for the propane dehydrogenation (PDH), the activity and stability of which are still far below the requirement for the industrial application. Thus, the development of an efficient catalyst is highly desired to advance the green CO2-ODP process.

Moreover, taking the redox nature of the CO2-ODP reaction into account, the activation of C-H bonds in propane must be synchronized with that of the C=O bonds in CO2 molecules irrespective of the catalysts employed, which are important topics for the heterogeneous catalysis. [2] Based on our understanding on the redox properties of CeO2 , in this work, the promotional effect of CeO2 on Pt-Sn/SiO2 for CO2-ODP was investigated by preparing the catalysts with the simple impregnation method. The reaction results indicate that the conversion of both propane and CO2 was significantly increased by adding CeO2 into Pt-Sn/SiO2 while the selectivity of propylene was still kept over 90%. From the characterization results of XRD, TPR, XPS, Raman, and DRIFTS, the strong electronic interactions between CeO2 and Pt led to a higher dispersion of Pt, and the lattice oxygen over CeO2 consumed during activating propane was replenished with the activation of CO2, the detailed reaction and mechanistic results of which will be presented.

Acknowledgements The authors thank the financial supports of the National Natural Science Foundation of China (21636006)

References

P.Michorczyk, K. Zeńczak-Tomera, et al., Journal of CO2 Utilization, 2020, 36: 54-63

Z. W. Liu, C. Wang, et al., ChemSusChem, 2011, 4(3): 341-345 O-A23: The effects of calcination atmosphere on Ni/Ce0.8Zr0.2O2 catalyst for carbon dioxied reforming of methane Beom-Jun Kim, Yeol-Lim Lee, Ho-Ryong Park, Hyun-Seog Roh* Department of Environmental Engineering, Yonsei University, Wonju, Republic of Korea (*Corresponding author: [email protected])

Development of selective and robust CDR (Carbon Dioxide Reforming of methane,

CH4 + CO2  2H2 + 2CO) catalysts remains a major research challenge in the field of heterogeneous catalysis. Due to their low cost compared with precious metal, Ni- based catalysts have been extensively studied for CDR application, but they suffer from excessive carbon deposition and severe thermal sintering. Partially successful attempts to reduce these adverse effects include the use of supports with strong basicity and/or supports containing significant concentrations of oxygen vacancies. The oxygen ion lability (or lack of it) of such materials is related to their O2− mobility and OSC (Oxygen Storage Capacity), which determine their propensity to provide mobile oxygen to metal particles dispersed on their surfaces. This property can strongly modify the intrinsic catalytic activity because the CDR reaction accompanies the move of oxygen. In addition, this mobile oxygen may gasify the carbons deposit at the active sites, which can enhance the catalytic stabiality. The investigation of such effects in the CDR is the main objective of the present investigation.

In this study, 5 wt.% Ni/Ce0.8Zr0.2O2 catalyst for the CDR was prepared by impregnation method, controlling the calcatination atmosphere. The various calcination atmospheres (N2, H2/N2, and Air) were applied to investigate the effect of calcination atmosphere on physicochemical properties and catalytic performance of a

Ni/Ce0.8Zr0.2O2 catalyst. Among the prepared support materials, we confirmed that the

Ce0.8Zr0.2O2 calcined at N2 atmosphere exhibited the highest OSC and basicity. To understand correlation between physicochemical properties of the catalyst and catalytic activity, the catalysts were characterized using XRD, BET, CO2-TPD, H2-TPR,

H2-chemisorption, and XPS analysis.

O-A25: Promoting Propane Dehydrogenation with CO2 over

Ga2O3/SiO2 by Eliminating Ga-Hydrides Yi Liua, Guanghui Zhanga,*, Jianyang Wanga, Jie Zhua, Xinbao Zhanga, Chunshan Songa,b,*, Xinwen Guoa,* a State Key Laboratory of Fine Chemicals, PSU-DUT Joint Center for Energy Research, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China b Department of Chemistry, Faculty of Science, the Chinese University of Hong Kong, Shatin, NT, Hong Kong, China E-mail: [email protected]; [email protected]; [email protected]

Abstract: Due to the shortage of propylene supply and the development of shale gas, there is increased interest in on-purpose propane dehydrogenation (PDH) technology for propylene production. Ga-based catalysts have great potential in PDH, due to the high activity, low carbon deposit and deactivation. Ga-hydrides formed during PDH reduce the rate, selectivity and yield of propylene. In this contribution, CO2 is introduced into PDH as a soft oxidant to eliminate the unfavorable intermediate

δ+ 3+ species Ga –Hx re-generating Ga –O pairs, and also minimize coke deposition thereby improving the catalytic performance. In situ diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy experiments show that CO2 can effectively eliminate

δ+ Ga –Hx. At different temperatures, co-feeding CO2 during PDH over Ga2O3/SiO2 catalysts with different loadings significantly improves the stability of the conversion and selectivity, especially the latter, and provide a new dimension for improving the performance of PDH process.

Fig. The improvement of C3H6 selectivity caused by CO2 over 3Ga2O3/SiO2. O-A26: CO and CO2 hydrogenation on iron carbide particles of different size Marian Chena, Nico Fischera, Henrik Kotzéa, Bruno Chaudretb, Dominikus Heiftb, Michael Claeysa aDepartment of Chemical Engineering, University of Cape Town, South Africa bLaboratoire de Physique et Chimie des Nano-objets, Institut National des Sciences Appliquées, Toulouse, France

The Fischer-Tropsch synthesis will play a key role in the production of sustainable fuels and chemicals from CO2 (pre-converted to CO) and green hydrogen. Whilst the reaction is known to be structure sensitive for cobalt-based catalysts with inferior performance of small particles (low activity, high methane selectivity), contradictory findings have been reported for iron-based catalysts.1 In this study very well defined iron carbide particles have been prepared via carburisation (in synthesis gas) of metallic precursors derived via a method described by Chaudret et al.2. These particles, which are very homogeneous in terms of size (see figure below), have been supported on a carbon support and were tested for CO and CO2 hydrogenation, for which iron-based catalysts also display significant activity (Riedel) and for which particle size dependency has not been studied yet.

20 nm Strong size dependent catalyst performance with inferior activity and selectivity was observed in our studies, which were supported by thorough catalyst characterisation including the use of in-situ techniques.

1. W. Ma, A.K. Dalai, Reactions 2 (2021) 62-77. 2. A. Meffre, B. Mehdaoui, V. Kelsen, P.F. Fazzini, J. Carrey, S. Lachaize, M. Respaud, B. Chaudret, Nano Letters 12(9) (2012) 4722-4728. O-A27: Catalytic conversion of CO2 to produce greener hydrocarbons. C. K. Poh1*, K. M. Y. Kwok1, J. Chang1, S. C. Teo1, T. C. C. Seah1, L. Chen1, A. Borgna1 H. Kamata2, T. Hashimoto2, N. Mizukami2, Y. Ishida2

1Institute of Chemical and Engineering Sciences, 1 Pesek Road, Jurong Island, 627833 Singapore 2IHI Corporation, 1-1 Toyosu 3-chome, Koto-ku, Tokyo, 135-8710 Japan

*Corresponding authors: [email protected]

CO2 emission in 2010 was reported to be 49 GtCO2eq, and 35% (17 GtCO2eq) of the GHG emissions were due to power generation where 81.3% were from fossil fuels1. The ideal decarbonization strategy appears to be the adoption of hydrogen, a fuel without carbon. However, hydrogen technologies are not matured yet. There is a requirement in R&D in hydrogen storage, fuel cells for power generation, and establishment of renewable hydrogen supply chain and infrastructure. Therefore, it is unlikely to be ready soon. In contrast, “Carbon Capture, Utilisation and Storage” has been recognised by Intergovernmental Panel on Climate Change and International Energy Agency2 as one of the strategies for mitigating climate change in the transitional period to global low-carbon economy. Institute of Chemical Engineering and Sciences (ICES, Singapore) has been working with IHI Corp, Japan on CO2 conversion to hydrocarbons for years. By utilising hydrogen produced from renewable energy sources, CO2 can be converted to hydrocarbons via methanation or modified Fischer-Tropsch reaction. Combining our expertise in catalyst development, reactor design, and process engineering, we have achieved significant improvements and bringing the technology closer to commercialization. Further development to bring a breakthrough in next generation catalysts for CO2 conversion may be achieved by the Accelerated Catalyst Development Platform (ACDP) established by ICES. Reference 1. Edenhofer, O., Pichs-Madruga, R. & Youba, S. IPCC, 2014: Climate Change 2014: Mitigation of Climate Change. vol. 3 (Cambridge University Press, 2014). 2. Kheshgi, H., de Coninck, H. & Kessels, J. Carbon dioxide capture and storage: Seven years after the IPCC special report. Mitig. Adapt. Strateg. Glob. Chang. 17, 563–567 (2012). O-B2: Opportunities and Limits of CO2 Recycling in a Circular Carbon Economy: Techno-economics, Critical Infrastructure Needs, and Policy Priorities Amar Bhardwaj, Colin McCormick, and Julio Friedmann Center on Global Energy Policy, Columbia University, New York, United States

Despite growing efforts to drastically cut carbon dioxide (CO2) emissions and address climate change, energy outlooks project that the world will continue to rely on certain products that are currently carbon-intensive to produce but have limited alternatives, such as aviation fuels and concrete. Converting CO2 into valuable chemicals, fuels, and materials has emerged as an opportunity to reduce the emissions of these products. However, these CO2 recycling processes have largely remained costly and difficult to deploy, underscoring the need for supportive policies informed by analysis of the current state and future challenges of CO2 recycling. In this study, we examined 19 electrochemical and thermochemical CO2 recycling pathways to understand the opportunities and the technical and economic limits of

CO2 recycling products gaining market entry and reaching global scale. The pathways were designed to consume renewable electricity and use chemical feedstocks derived from electrochemical pathways powered by renewable energy. Across these CO2 recycling pathways, we evaluated current production costs, sensitivities to cost drivers, carbon abatement potential, critical infrastructure and feedstock needs, and the effect of subsidies. We find that the costs of most pathways are high, and dominated by the cost of electricity and chemical feedstocks. Based on these cost estimates, we identify the most economic pathways for early market entry and recommend demand pull policies to begin deploying them. The strongest driver for cost reductions is catalyst selectivity and activity, motivating a focus on catalyst innovation to bring down costs.

We also find that CO2 recycling pathways at global scale would each require trillions of dollars of investment in supporting infrastructure and would consume thousands of terawatt hours of electricity annually. Therefore, a concurrent focus on building out necessary infrastructure is needed to support the scale-up of CO2 recycling. With the proper approach to advancing CO2 recycling, we find these pathways could abate gigatonnes of CO2 per year at global scale. O-B3: Manganese Polypyridyl Carbonyl Complexes: A Model for

Electrocatalytic and Photocatalytic Reduction of CO2 to CO

Andrew B. Bocarsly*, Steven E. Tignor, Hsin-Ya Kuo Department of Chemistry, Princeton University, New Jersey, United States

The complex [BrMn(bpy)(CO)3] is an established electrocatalyst effecting the reduction of CO2 to CO in the presence of a proton source. We use this complex as a “testbed” to study the interactions of protons and electrons during the conversion of CO2 to CO. To that end, we have dangled a phenolic moiety from various bipyridinering positions in order to demonstrate a role for hydrogen bonding in this process.1 These studies have indicated the need for a key hydrogen bond that appears to facilitate the oxygen transfer portion of the transformation. H vs. D isotope studies indicate a complex set of equilibria associated with this proton coupled electron transfer reaction (PCET).2 A major experimental challenge associated with the study of this and related complexes is the that they undergo facile photochemical decomposition under typical room light conditions. We recently reported that the cyanide bridged dimer ([Mn(bpy)(CO)3]2(μ-CN))+, eliminates this deleterious photochemistry.3 Further, this cyanide bridged dimer is not only a viable electrocatalyst, but is effective as a photocatalyst for the reduction of CO2 to CO when irradiated at wavelengths that absorb into the metal to bpy charge transfer band. In this photochemical reaction, the initial photodissociation of a CO ligand provides a site for CO2 binding. Follow up photochemically induced electron transfers lead to the reduction of the bound CO2 ligand. Mechanistically, the photochemical reduction of CO2 appears to follow the electrochemical reduction of CO2 using this complex. The reactivity of {[Mn(bpy)(CO)3]2(μ-CN)}+ suggests that the active catalytic site may be associated with a labile CO ligand. To test this idea, [Mn(bpy)(CO)4]+ was synthesized and studied as an electrocatalyst for the transformation of interest. Our data demonstrates that this species is a key intermediate in the catalytic cycle leading to CO production.4 References: 1. Agarwal, J.; Shaw, T. W.; Schaefer, H. F.; Bocarsly, A. B., Design of a Catalytic Active Site for Electrochemical CO2 Reduction with Mn(I)-Tricarbonyl Species. Inorg Chem 2015, 54 (11), 5285-5294. 2. Tignor, S. E.; Shaw, T. W.; Bocarsly, A. B., Elucidating the origins of enhanced CO2 reduction in manganese electrocatalysts bearing pendant hydrogen-bond donors. Dalton Transactions 2019, 48 (33), 12730-12737. 3. Kuo, H. Y.; Lee, T. S.; Chu, A. T.; Tignor, S. E.; Scholes, G. D.; Bocarsly, A. B., A cyanide-bridged di-manganese carbonyl complex that photochemically reduces CO2 to CO. Dalton Transactions 2019, 48 (4), 1226-1236. 4. Kuo, H. Y.; Tignor, S. E.; Lee, T. S.; Ni, D.; Park, J. E.; Scholes, G. D.; Bocarsly, A. B., Reduction-induced CO dissociation by a [Mn(bpy)(CO)4][SbF6] complex and its relevance in electrocatalytic CO2 reduction. Dalton Trans 2020, 49 (3), 891-900. O-B4: Visible-light driven photocatalytic CO2 conversion over

mesoporous CdSxSe1-x Han Sol Jung1, 2 , Yong Tae Kang1, 2 1School of Mechanical Engineering, Korea University, Seoul, Republic of Korea; 2Center for Plus Energy Building Innovative Technology, ERC, Seoul, Republic of Korea

Photocatalytic CO2 conversion technology has been extensively paid attention to convert CO2 and water into oxygen and fuels using solar light as an energy source, mimicking the natural photosynthesis reaction which uses photocatalyst that converts energy from solar energy into chemical energy. Recently, photocatalytic CO2 conversion has been highlighted to the most promising strategy again for directly transforming CO2 and solar energy into energy-rich chemical fuels in eco-friendly way.

However, this technology for using solar energy to convert CO2 into useful fuels is still far from practical application due to its low conversion rate and selectivity, and lack of facile synthesis methods. Therefore, transition metal oxides with oxygen vacancies are the most widely investigated photocatalysts for the conversion of CO2 to hydrocarbons, but there is only a few studies using metal chalcogenides for photocatalysts which have unique properties and semiconducting properties due to lack of facile synthesis methods and suitable precursors [1].

In this study, we successfully synthesized mesoporous CdSxS1-x via hard templating method by varying amount of precursors, and characterized its opto- physical properties using various techniques. Using the synthesized materials, CO2 conversion experiments are conducted on slurry type photocatalytic reactor under controlled conditions, and conversion yields are calculated using TCD-FID equipped gas-chromatography as reported on the previous study [2]. It is found that synthesized materials show great opto-physical properties and the CO2 photoconversion performance are highly effected by CO2 adsorption capacities and crystal phases.

References [1] Borchardt, L. (2013). Carbide and Carbide-Derived Carbon Materials with Hierarchical Pore Architecture. [2] Lee, Y. Y., Jung, H. S., Kim, J. M., & Kang, Y. T. (2018). Photocatalytic CO2 conversion on highly ordered mesoporous materials: comparisons of metal oxides and compound semiconductors. Applied Catalysis B: Environmental, 224, 594-601. O-B7: High Efficiency Solar-to-CO Conversion System Utilizing

Dilute CO2 Gas Catalyzed by Au25 Clusters

Beomil Kim, Jihun Oh*

Department of Material Science Engineering, Korea Advanced Institute of Science and Technology, Daejeon, South Korea

With increasing solar electricity generation, CO2 electrochemical conversion system has engaged great attention as it offers opportunities to store intermittent solar energy in form of chemical energy. However, the efficiency of converting solar energy to chemical energy is limited by a liquid-phase CO2 electrolyzer having a low performance due to low solubility of CO2 gas. In this work, we design a highly efficient and selective CO2 electrolyzer by adopting an Au25 nanocluster–immobilized gas diffusion electrode (GDE), which can initiate electrocatalytic reduction of CO2 to CO -2 with negligible energy loss and achieve a high jCO of 540 mA cm in a gas phase reactor. By integrating the Au25–immobilized GDE electrolyzer (EZ) and a

Ga0.5In0.5P/GaAs photovoltaic cell (PV), we achieved one of the highest solar-to-CO

(STC) efficiency (19.5%). In addition, our Au25 nanocluster exhibits high binding affinity with CO2 such that our PV-EZ system reduces CO2 to CO in low CO2 partial pressure without significant loss of selectivity and energy efficiency compared to utilizing high purity CO2 gas, resulting in 15.9% STC efficiency from a 10% CO2 gas stream, a typical CO2 concentration in a flue gas.

O-B8: CO2-treated Titanium Carbide Mxenes as Dual Sulfur Cathode and Modified Separator in Lithium-Sulfur Batteries Dong Kyu Lee, Chi Won Ahn, Jae W. Lee Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea

Lithium-ion batteries (LIBs) have been developed and extensively utilized in many applications over the past three decades and have shown advantages including long life and good rate capability. However, LIBs do not meet the requirements for large- scale energy-storage systems and electric vehicles due to their high cost and limited energy density (~150 Wh kg-1). In order to overcome the limitations of LIBs, lithium sulfur batteries (Li-S) have been considered to be one of the most promising next- generation energy systems, due to the high theoretical capacity (1672 mAh g-1), high energy density (2600 Wh kg-1), natural abundance, low cost and environmental friendliness of sulfur. Nevertheless, there are obstacles that should be overcome for the development of Li-S batteries, including the insulating nature of sulfur and the shuttle phenomenon of dissolved lithium polysulfides (LPSs) in liquid electrolytes result in critical problems such as low coulombic efficiency, loss of active material, and rapid capacity decay. Here, delaminated transition metal carbides (MXenes) are oxidized using CO2 (Oxi-d-MXenes) and used them as both sulfur cathode electrode and modified separator coated onto the glass fiber (GF) without a conductive material and binder to suppress the diffusion of LPSs. MXenes, as one class among numerous two-dimensional (2D) materials, have been highlighted in various applications such as batteries, catalysts, transparent conducting coatings, sensors, and water purification o systems. Oxi-d-MXenes annealed at 900 C using CO2 gas formed perfectly exhibited a clear phase of rutile-TiO2 nanocrystalline particles on their two-dimensional sheets. Li–S batteries fabricated with the Oxi-d-MXenes cathode and the Oxi-d-MXenes- modified separator demonstrated high coulombic efficiency (nearly 99 %) and retained a capacity of about 900 mAh g−1 after 300 cycles at a current density of 1C. Our results show that the Oxi-d-Mxenes using CO2 gas should be used for components of Li-S batteries due to the strong chemical and physical adsorption between Oxi-d-Mxenes and LPSs and the excellent template to accommodate the sulfur.

O-B9: Effect of CO2 partial pressure on C2H4 activation in

electrochemical CO2 reduction Hakhyeon Song, Jihun Oh* Department of Materials Sciencen and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea

Electrochemical CO2 reduction (CO2RR) has attracted huge interests to produce value-added chemical fuels and feedstock. Especially, the formation of ethylene (C2H4) is promising as it is an important building block for plastics and other chemicals with a high unit price with a large market [1]. However, for economically competitive C2H4 formation from CO2RR, high performance should be achieved [2].

Cu is the unique metal catalyst that forms multi-carbon products during CO2RR, but has low C2H4 selectivity as it can produce about 16 hydrocarbons and oxygenates [3]. Herein, I will present our strategies to develop the enhanced performance of

C2H4 by controlling CO2 partial pressure (pCO2). We used a flow cell with Cu nanoparticles deposited uniformly by e-beam evaporation on a gas diffusion electrode

(GDE) to investigate pCO2 dependent catalytic activity of Cu for all major CO2RR products at high electrochemical current density. The activity of CO2RR is highly affected by pCO2 at various applied potentials. For instant, a dilute CO2 stream selectively activates C2H4 formation with significant reduction of overpotential (~400 mV) to achieve ~50% C2H4 Faradaic efficiency. Although it is believed that high concentration of surface bound CO is required for C2H4 formation, we show that excessive supply of CO2 interferes with C–C coupling and suppress C2H4 reaction pathways. Furthermore, with systematic control of pCO2 and the applied potential, we optimized CO2 concentration to reach FE and current density of C2H4 superior in low pCO2 compared to 100% pCO2. Detailed analysis of the pCO2 dependent CO2RR will be presented in terms of critical parameters for the reaction kinetics and mechanisms such as recombination, binding energy, and site-blocking of surface bound intermediates.

[1] Science, 364 (2019) 6438. [2] Ind. Eng. Chem. Res., 57 (2018) 2165-2177. [3] Energy Environ. Sci., 5 (2012) 7050-7059.

O-B10: CO2 photochemical reduction by coprocessing with water: simple synthesis and thorough characterization of metal oxides as photocatalytic p-n heterojunctions

Davide M.S. Marcolongoa,b, Francesco Nocitoa,b, Angela Dibenedettoa,b,c*

aDepartment of Chemistry, University of Bari “Aldo Moro”, Via E. Orabona, 4, 70126 Bari, IT; bInteruniversity Consortium Chemical Reactivity and Catalysis, CIRCC, Via Celso Ulpiani, 27, 70126

Bari, IT; c IC2R srl, c/o Tecnopolis, 70018 Valenzano (BA), IT

The transformation of the spent carbon of CO2 into working carbon, according to Carbon Capture and Utilization (CCU) strategies, is a valuable key step to curb carbon transfer from subsoil to atmosphere, with the aim of establishing a Carbon Circular Economy (CCE).[1,2] Within this frame, CCE has a great potential to produce fuels by conversion of CO2, a process requiring large input of energy, which must be produced by environmentally friendly perennial energy sources, and non-fossil hydrogen. Besides the thermal reduction of CO2 with H2 or the CO2 electroreduction in water, routes almost ready to application, the direct utilization of solar energy under photocatalytic conditions represents an interesting strategy towards production of so-called Solar Fuels. CO2 can be directly co-processed with H2O (as protons and electrons source) under UV-Visible radiation, also if this strategy still records low production rates.[2,3] To this end semiconductor materials, with proper size/morphology properties should be used.[3] They should be able, on their own or combined with other materials, to efficiently absorb radiations and use the so photogenerated excitons for CO2 reduction and H2O oxidation. The characterization phase of such materials, spanning from electronic band structure to light-harvesting and electrochemical properties, is fundamental to establish key structure/property/application relations.[1,4] Here we report about the synthesis and accurate characterization of metal-oxide systems, alternative to TiO2,[1,4–6] to be used as photocatalysts in CO2-H2O coprocessing. Both spectroscopic and electrochemical characterization are carried out to evaluate the energy levels and the properties of photoinduced charge carriers.[4] The data collected can be useful to a deeper comprehension whether p-n heterojunctions are formed and about their contribution to the photocatalytic process. Acknowledgements

IC2R srl and CIRCC are acknowledged for funding. References [1] D. M. S. Marcolongo, A. Dibenedetto, M. Aresta, In Advances in Inorganic Chemistry; van Eldik, R., Hubbard, C., Eds.; Elsevier, 2021. [2] M. Aresta, A. Dibenedetto, The Carbon Dioxide Revolution, 1st ed.; Springer International Publishing, 2021. [3] X. Li, J. Yu, M. Jaroniec, X. Chen, Chem. Rev. 2019, 119 (6), 3962–4179. [4] D. M. S. Marcolongo, F. Nocito, N. Ditaranto, M. Aresta, A. Dibenedetto, Catalysts 2020, 10, 980. [5] S. Navalón, A. Dhakshinamoorthy, M. Álvaro, H. García, ChemSusChem 2013, 6 (4), 562–577. [6] S. N. Habisreutinger, L. Schmidt-Mende, J. K. Stolarczyk, Angewandte Chemie - International Edition 2013, 52 (29), 7372–7408. O-B11: Key enablers for producing low-carbon CO2 electroreduction products Javier Fernandez-Gonzalez1, Marta Rumayor1, Antonio Dominguez-Ramos1 and Angel Irabien1 1Department of Chemical and Biomolecular Engineering, University of Cantabria, Santander, Spain

Life Cycle Assessment studies have gained increasing interest as powerful ex-ante tools for evaluating the sustainability of the Carbon Capture and Utilization processes

(CCU). Power-to-X technologies by CO2 electroreduction are promising artificial carbon recycling routes, but their low Technology Readiness Level (TRL~4) and long implementation horizon entail significant uncertainty in the intrinsic electroreduction conditions (endogenous) and the technological/energy/policy situation (exogenous). This work aims to provide a rationalized range of the cradle-to-gate carbon footprint

(CF) of several CO2-based products and identify the key enablers (endogenous and exogenous requirements) that lead to low-carbon products. A flexible mathematical model is created [1] to assess the production of gas (C2H4, CH4) and liquid products

(HCOOH, CH3OH) and evaluate their environmental profile. Monte-Carlo simulations under different scenarios based on reviewed literature [2] are carried out, showing that HCOOH presents the highest probability of reducing emissions under a normative 2030 scenario. Heat electrification is the critical exogenous variable in the liquid products, while low-carbon electricity and by-product valorization drive the reduction in the CF of CO2-based CH4 and C2H4. Substitution of 50% of fossil products with electroreduction alternatives could save for Europe up to 113-242 Mt CO2 per year, evidencing the interest in developing CCU technologies under proper scenarios.

Acknowledgments Javier Fernández-González and Marta Rumayor would like to thank the financial support of the Spanish Ministry of Science, Innovation and Universities for the concession of a FPU grant (19/05483) and a Juan de la Cierva postdoctoral contract (IJCI-2017-32621), respectively.

References [1] M. Rumayor, A. Dominguez-Ramos and A. Irabien, ACS Sustain. Chem. Eng., 2020, 8, 11956.

[2] S. Kibria Nabil, S. McCoy and M. G. Kibria, Green Chem., 2021, 23, 867. O-B12: Photo-activated rhodium-based metal-organic polyhedra

assemblies for selective CO2 reduction Ashta C. Ghosh,† Alexandre Legrand,# Rémy Rajapaksha,† Gavin A. Craig,# ♦ Pascal Bargiela,† Zahraa Shahin,† Caroline Mellot-Draznieks,║ Capucine Sassoye, ║ Gabor Balazs,‡ David Farrusseng,† Shuhei Furukawa,# Jérôme Canivet,† Florian M. Wisser‡

† Research Institute for Catalysis and Environment of Lyon (IRCELYON), France, # Institute for Integrated Cell-Material Sciences, Kyoto University, Japan, ║ Sorbonne Université, France, ‡ University of Regensburg, Germany.

Metal-organic polyhedra are an emerging class of well-defined hybrid compounds with a high number of open metal sites organised around an inner cavity, making them appealing candidates for catalytic applications. Here we demonstrate the high potential of paddlewheel-based rhodium metal-organic cuboctahedron [Rh2(bdc)2]12 (bdc = benzene-1,3-dicarboxylic acid) [1] as very efficient catalysts for selective photochemical carbon dioxide to formic acid reduction. For better recyclability, the molecular metal-organic cuboctahedra are heterogenized into three-dimensional supramolecular polymers [2]. Surprisingly, the catalytic activity per Rh atom is up to 30 % higher in the heterogenized system than in homogeneous solution of Rh metal- organic polyhedra, and yields turnover frequencies of up to 60 h-1 and production rates of approx. 2.7 gram formic acid per gram of catalyst per hour, unprecedented in heterogeneous photocatalysis. Pair distribution function analysis shows that the active center are Rh paddlewheel units, which remain intact and well-defined throughout the catalysis. The enhanced catalytic activity compared to the molecular subunits is investigated by XPS spectroscopy and electrochemical characterization, showing that the self-assembly into supramolecular polymers increases the electron density on the active site, making the overall reaction thermodynamically more favourable. The catalyst can be recycled for at least 4 cycles, with no changes of its molecular structure.

Figure 1. Schematic representation of (a) the SBU of Rh-MOP-based materials, Rh-MOP = [Rh2(R- bdc)2]12,(R = 5-dodecoxy (C12) or H); and (b) the Rh-MOF, Rh3BTC2. H-atoms are omitted for clarity. The active site of both classes of materials is highlighted (middle), where the reduction of CO2 into formic acid occurs.

References. [1] S. Furukawa, N. Horike, M. Kondo, Y. Hijikata, A. Carné-Sánchez, P. Larpent, N. Louvain, S. Diring, H. Sato, R. Matsuda, R. Kawano, S. Kitagawa, Inorg. Chem. 55 (2016) 10843; [2] A. Carné-Sánchez, G. A. Craig, P. Larpent, T. Hirose, M. Higuchi, S. Kitagawa, K. Matsuda, K. Urayama, S. Furukawa, Nat. Commun. 9 (2018) 2506. O-B13: Introducing hyperbranched morphology TiO2 nanorods and CuO-TiO2 material for CO2 photoreduction to solar fuel

Stelios Gavrielides*, Jeannie Z. Y. Tan and M. Mercedes Maroto–Valer

Research Centre of Carbon Solutions (RCCS), School of Engineering & Physical Sciences, Heriot–Watt University, Edinburgh, United Kingdom. *Corresponding author: [email protected] The utilisation of CO2 for the production of fuels such as CH4 and CO provides a very appealing strategy for reducing the anthropogenic CO2 emissions, which are the main contributor to the constantly rising concentration of CO2 in the atmosphere. Utilising light to drive the conversion of CO2 to fuels is a promising approach that could potentially avert the effects of global warming and energy crisis.1,2 Previous research has shown that the morphology of the photocatalyst can greatly affect its 3,4 performance. Herein, we propose the use of the novel TiO2 hyper-branched nanorod morphology (HBNs) for CO2 photoreduction. The HBNs performance is compared to the literature standard Degussa P25 TiO2. The reaction was performed in a CO2 photoreduction rig that was built within the RCCS group, connected with an inline GC (Agilent 7890B) at 40 °C and a light source (300-600 nm). HBNs produced a -1 -1 maximum of CH4 (15.53 µmol/gcath ) and CO (668.8 µmol/gcath ), which were 10 and 15 times, respectively, higher than P25. Cumulatively, the HBNs produced 33 and 30 times more CH4 and CO respectively when compared to P25. The improved performance was attributed to the HBN morphology, which has higher surface area, and allows for light penetration3,5,6. To further optimise the product selectivity of the

TiO2 HBNs, a CuO-TiO2 HBN compound material was fabricated. The composite material of CuO-TiO2 exhibited an improved CH4 selectivity 2.3% to 30.4%.

Additionally, the CuO containing HBNs showed stable production of CH4 throughout the experiment, whereas the as prepared TiO2 HBNs revealed a deactivation after 200 minutes. References: 1. O. Ola and M. M. Maroto-Valer, J. Photochem. Photobiol. C: Photochem. Rev., 2015, 24, 16-42. 2. O. Ola and M. Mercedes Maroto-Valer, Catal. Sci. Tech., 2014, 4, 1631-1637. 3. S. Gavrielides, J. Z. Y. Tan, E. S. Fernandez and M. M. Maroto-Valer, Faraday Discussions, 2019, DOI: 10.1039/C8FD00181B. 4. J. Z. Y. Tan, F. Xia and M. M. Maroto-Valer, ChemSusChem, 2019, 12, 5246-5252. 5. J. Z. Y. Tan, Y. Fernández, D. Liu, M. Maroto-Valer, J. Bian and X. Zhang, Chemical Physics Letters, 2012, 531, 149-154. 6. W.-Q. Wu, H.-S. Rao, H.-L. Feng, X.-D. Guo, C.-Y. Su and D.-B. Kuang, Journal of Power Sources, 2014, 260, 6-11. O-C1: Evaluation of Carbon-based cathode materials for CO2 Conversion to C1-C2 Compounds in Microbial Electrosynthesis Cells Abraham Gomez Vidales1, Emmanuel Nwanebu2, Sasha Omanovic2, Hongbo Li1, and Boris Tartakovsky1 1National Research Council of Canada, Montreal, QC, Canada 2McGill University, Montreal, QC, Canada

In this study, CO2 conversion to C1-C2 compounds such as acetate and ethanol was achieved in a laboratory-scale two chamber microbial electrosynthesis (MES) cell.

The anode compartment housed a Ti/IrO2 mesh, while the cathode compartment contained various cathode materials. The cathode compartment was inoculated with anaerobic sludge and fed continuously either with a Na2CO3 solution or CO2 (gas). In the first experiment, three cathode lattices (3D printed, electrically-conductive polymers) containing either electrodeposited Ni, Ni-Fe, or Ni-Fe-Mn materials were compared using Na2CO3 solution. The best performing NiFeMn lattice showed stable production of CH4, H2 as well as acetate after 20 days of operation reaching a Coulombic efficiency of 80%. This is by 67% higher than that of the non-coated lattice. In the second experiment performance of several carbon-based materials was evaluated in a larger MES setup fed with CO2. Carbon felt, granular activated carbon (GAC), and conductive ABS polymer rods were used. In this experiment, the carbon felt cathode had the highest volumetric rate of CH4 production with a Coulombic efficiency of 85%, while the conductive ABS cathode showed the highest volumetric rate of acetate production with similarly high Coulombic efficiency. Finally, in the third experiment, a hybrid (conductive polymer lattice and non- conductive microbial support) cathode was used to maximize either CH4 or acetate production. In these experiments, operating conditions such as applied voltage, pH, and CO2 flow were constantly monitored and adjusted in order to maximize the CO2 conversion efficiency.

O-C2: Improving Sustainability in Biobased Manufacturing Dr Fraser Brown1, Dr Reuben Carr1, Prof Frank Sargent2 1Ingenza Ltd, Edinburgh, Scotland, UK 2School of Natural & Environmental Sciences, Newcastle University, Newcastle, England, UK

Climate change is challenging how we all live including future ways in which energy will be generated and consumed. As a result, there is an urgent need to dramatically cut CO2 emissions generated from conventional fossil fuels by switching to alternative renewable feedstocks. Industrial biotechnology (IB) has a critical role to play in addressing these global issues. Ingenza is developing innovative IB solutions to enable green hydrogen bioconversion of CO2 into a sustainable feedstock for biological manufacturing. Using specific enzymes we have demonstrated it is possible to catalyse the reduction of CO2 with excellent efficiency to increase the cellular reducing power required in engineered microbial hosts to improve carbon conversion efficiency from feedstock to product during fermentative bioprocessing. We believe this technology can be deployed to develop sustainable, cost competitive biobased manufacturing production routes towards commodity chemicals and fuels whilst ensuring net-zero CO2 emissions cans be achieved. This approach could significantly benefit several industry sectors who are focussed on reducing their carbon footprint to meet future greenhouse gas target levels.

O-C3: Biomass-derived molecules valorization: from furfural to 2,5- furan dicarboxylic acid using a two-step oxidation/carboxylation process

Domenico Linsalataa,b, Gaetano D’Onghiab, Francesco Nocitob,c,

Angela Dibenedettoa,b,c*, Michele Arestaa,b

aIC2R s.r.l., c/o Tecnopolis, 70018, Valenzano (BA), IT; bInteruniversity Consortium Chemical

Reactivity and Catalysis, CIRCC, via Celso Ulpiani, 27, 70126, Bari, IT; cDepartment of Chemistry, University of Bari “Aldo Moro“, via Orabona, 4, 70126, Bari, IT Biomass-derived oxygenate-species can be considered an alternative to fossil resources derived chemicals. Among them furfural, that can be easily produced from xylose dehydration over acid catalysts [1], has received great attention as precursor of commodity chemicals [2]. In this paper we present a two-step process for the conversion of furfural into 2,5-furan dicarboxylic acid (FDCA) that can replace fossil sourced phtalic acid used for the production of polyesters such as polyethene phtalates (PET). Polyethene furoate–PEF, has the right properties for being converted into fibers, films and packaging materials. The highly selective synthetic procedure is based on two steps (Scheme 1), namely: i) a heterogeneously catalyzed aerobic oxidation of furfural to furoic acid in water and ii) the direct carboxylation of the latter to 2,5-FDCA.

Scheme 1. Route for producing 2,5-FDCA from C5-polyols In the first step, furoic acid is obtained with 20% yield and 100% selectivity using low cost mixed metal oxides (MMO) as catalysts: both the unreacted reagent and the catalyst are recovered and re-used in subsequent cycles to improve the conversion [3]. In the second step, furoic acid is converted into 2,5-furan dicarboxylic acid in presence or absence of CO2 [4]. A key copper-di-furanoate intermediate has been synthesized and fully characterized that is able to promote the carboxylation at C5 of furoic acid affording 2,5-FDCA with 98% yield and 100% selectivity. The recovery and recycling of metal species make this process quite useful for synthetic purposes. Acknowledgements PRIME Project (0333000072 – POR-FESR, 14-20 ASSE I-I.1 B.2.2 -Bioeconomia) is acknowledged for financial support. References [1] L. Zhang, G. Xi, K. Yu, H. Yu, H. Wang, Industrial Crops and Products, 2017, 98, 68–75. [2] K. Dalvand, J. Rubina, S. Gunukula, M. C. Wheeler, G. Hunt, Biomass and Bioenergy, 2018, 115, 56-63. [3] M. Aresta et al, in preparation.

[4] F. Nocito, N. Ditaranto, A. Dibenedetto, Journal of CO2 Utilization, 2019, 32, 170-177. O-C4: Tailoring waste-derived materials for Ca-Looping application in thermochemical energy storage systems Paula Teixeira, Eunice Afonso, Carla I.C. Pinheiro CQE–Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Avenida Rovisco Pais 1, 1049-001 Lisboa, Portugal Thermochemical energy storage (TCES) is one of the most promising large-scale options, consisting of using the high temperatures attained in a concentred solar power (CSP) plant to drive an endothermic chemical reaction, and when energy is needed, the stored reaction products are brought together at the necessary conditions to drive the exothermic reverse reaction. The recently innovative application of the Calcium- looping (CaL) process for TCES based on the cyclic carbonation-calcination reaction

CaO (s) + CO2 (g) ↔ CaCO3 (s), is an interesting and promising choice since it fulfils the following requirements: low cost of non-toxic natural geological CaO precursors such as limestone or marble wastes, the high energy storage density (1790 kJ/kg of

CaCO3), and in addition, the high temperatures used during carbonation allow attaining high power cycles efficiencies. In the solar-driven CaL directly irradiated reactors, the solar absorptivity of CaO-based materials that typically have a white colour, is a limitation in terms of absorptivity. In this work the doping of TCES materials with “dark” additives with high solar absorptivity, like carborundum (SiC), is proposed to enhance the CaCO3 calcination efficiency and simultaneously act as CaO particles “spacer” hindering their sintering. The heat storage density (HSD) of four CaO-based wastes, from mining and marble industry (WMP) was evaluated in a fixed bed reactor using a carbonation - calcination temperature of 800 and 930 °C, respectively, and an atmosphere of 50% of CO2 in air. The solar absorptivity of the materials was assessed by UV-VIS technique. When the WMP is doped with 10-20 % of sludge the HSD of the

TCES material after 20 cycles duplicates (203 vs. 400-408 kJ/kg of CaCO3). The use of CaO-based waste-derived materials and sludge wastes as “dark” additives, is an interesting option for CaL-TCES systems. If integrated in the cement industry the CaL can be used for CO2 capture followed by CO2 valorization for TCES, and additionally, the spent CaO can be used as raw matter for clinker production, fulfilling the circular economy. 1. C. Pinheiro, A. Fernandes, C. Freitas, E.T. Santos, M.F. Ribeiro, Ind. Eng. Chem. Res., 55, 7860 (2016). 2. P. Teixeira, I. Mohamed, A. Fernandes, J. Silva, F. Ribeiro, C.I.C. Pinheiro. Separation and Purification Technology, 235, 116190 (2020) O-C5: Mathematical Model of a Microbial Electrosynthesis Cell for

the Conversion of Carbon Dioxide into Methane and Acetate

R. Gharbi1,2, S. Omanovic1, B. Tartakovsky2

1 Department of Chemical Engineering, McGill University, 3610 University St., Montreal, Quebec, Canada H3A 0C5 2 National Research Council of Canada, 6100 Royalmount Avenue, Montreal, QC, Canada H4P 2R2

CO2 conversion to methane and short-chain carboxylic acids in a microbial electrosynthesis cell (MESC) is an emerging approach for combining CO2 sequestration with the production of valuable commodities from a renewable source of carbon. While the production of methane and carboxylic acids (mainly acetate) in a MESC was demonstrated in several studied, process scale-up requires a simulation tool for thorough system analysis, optimization and techno-economic assessment. The dynamic mathematical model developed in this work simulates multiple product formation from CO2 at the MESC cathode taking into account the non-linear dynamics of microbial growth, the effects of various operating conditions, and CO2 transport between the electrode compartments. Using experimental results of our previous works consisting of a MESC with a continuous in-flow of CO2, model parameters were estimated; a good agreement between the model and the experimental results was obtained. The model is able to simulate the production of CH4, H2, and acetate via microbial, electrochemical, and bio-electrochemical pathways. Furthermore, the model simulates the growth and behavior of the different biomass populations present in the biofilm including acetogens, methanogens and electroactive bacteria. The simulation results show both dynamic and steady-state response of the system to changes in operating conditions.

O-C6: Modeling of methanol synthesis process based on the exhaust gas of an engine plant

Jae Hun Jeong1, Yoori Kim2, Se-Young Oh2, Myung-June Park3,4,*, Won Bo Lee1,* 1 School of Chemical and Biological Engineering, Seoul National University, Seoul 08826, Republic of Korea 2 Advanced Research Center, Korea Shipbuilding & Offshore Engineering, Seoul 03058, Republic of Korea 3 Department of Chemical Engineering, Ajou University, Suwon 16499, Republic of Korea 4 Department of Energy Systems Research, Ajou University, Suwon 16499, Republic of Korea

In this study, a methanol synthesis process from CO2 in the exhaust gas was designed to utilize CO2 and maximize the efficiency of the entire engine plant. The process consists of CO2 purification, reforming, and methanol synthesis; To remove inert gases in the exhaust gas, an acid gas removal unit (AGRU) was used to get the high concentration of CO2, which was used as a feed of reforming, along with CH4 and steam for the production of syngas. The produced syngas was hydrogenated for methanol synthesis. Kinetic models for both reforming and methanol synthesis were applied to the design of the reactors, and a process model was developed using a process simulator (UniSim Design Suite, Honeywell Inc.) to improve the performance of the entire process in aspects of thermal efficiency, reactor volume, and productivity, under a variety of feed compositions. Finally, techno-economic analysis was conducted on the total process to determine the profitability of the suggested process.

O-C7: Thermodynamic Analysis of CO2 Hydrogenation to Formic Acid Promoted by Ionic Liquid T.O. Bello, A.E. Bresciani, R.M.b. ALVES, C.A.O. Nascimento Polytechnic School, University of Sao Paulo, Sao Paulo, Brazil.

The hydrogenation of carbon dioxide (CO2) to formic acid is thermodynamically disfavoured starting from gaseous reactant with a standard Gibbs free energy (ΔG°298) of +32.9 kJmol−1 but is somewhat exergonic in aqueous solution. The conventional main route to produce formic acid is the esterification of formates with methanol to produce methyl formates using syngas from fossil sources as raw material. Moreover, different methods are used in academic research to promote the reaction, including the use of solvents or neutralization with a base to yield formamides. The product of the reaction requires rigourous separation operations and subsequently makes the process more complex. In this sense, the development of simple and efficient system for formic acid and methanol production is important. The aim of this study is to evaluate a set of process operating conditions to convert

CO2 to formic acid in an aqueous media with ionic liquid (IL) for maximum achievable yield. It is reported a thermodynamic analysis of CO2 hydrogenation to formic acid promoted by IL (1-ethyl-2,3-dimethylimidazolium nitrite, ([Edmim][NO2]). The analysis is conducted in Aspen Plus using the Gibbs free energy minimization method combined with a vapour-liquid equilibrium for solvation of the CO2 in ILs. The product components of the reaction are determined according to the reaction. Sensitivity analysis is carried out to show the effects of reaction temperature, pressure and the molar ratio of feed components (CO2, H2 and IL) on the equilibrium products. The ILs promoted system is very effective for the production of formic acid at 25°C and 17bar with a yield of ~60% formic acid at a CO2/H2/IL ratio of 1/2/2 achieving a CO2 conversion of ~80%. The calculated results shows a remarkable improvement in the production of formic acid compared to other previously conducted studies on hydrogenation of CO2 to formic acid without ILs, which represents a large potential to contribute for reducing CO2 released into atmosphere.

O-D1: Solid carbonation via membrane system for scalable CO2 utilization Young-Eun Hwang, Kyunam Kim, Hyeokjun Seo, and Dong-Yeun Koh* Department of chemical & biomolecular engineering, Korea Advanced Institute of Science and Technology(KAIST), Daejeon, Korea

A combination of established technologies enabled by scalable and modular devices makes it possible to realize net-zero CO2 emissions energy system. As a prototype of such a system, two systems have been devised to convert CO2. First, PIM-1(Polymer of Intrinsic Microporosity), which has very high permeability, was fabricated to assymmetric hollow fiber membrane. By feeding CO2 gas and model calcium- containing solution in the opposite direction, calcium carbonate was continuously synthesized inside the module. Quantitative assessments on the module performance and the potential problems such as scale formation were conducted. Based on the above results, calcium carbonate was synthesized from calcium-containing complex solution derived from real industrial by-products using commercial membrane contactor system. The relationship between module operation conditions and calcium carbonates production behavior was evaluated. By simultaneously exploiting both CO2 and industrial waste, cost-effective and reliable large-scale CCU can be realized.

O-D2: Physisorption-based Fiber Sorbent for Direct Air Capture

Jinhong Jeong1, Aqil Jamal2, Dong-Yeun Koh1,* 1Department of Chemical and Biomolecular Engineering, KAIST, Daejeon 34141, Republic of Korea 2Carbon Management Research Division, Research & Development Center, Saudi Aramco, Dhahran 31311, Kingdom of Saudi Arabia

One of the representative negative emission technologies (NET) of carbon dioxide to respond to climate change is direct air carbon capture and storage (DACCS) technology. Direct air capture adsorbs carbon dioxide in the air and makes it possible to utilize the adsorbed carbon dioxide. However, since it targets the dilute carbon dioxide present in the air, an aqueous solution absorbent or chemical adsorbent, which is difficult to regenerate, is used, and an expensive and energy-intensive process has to be used. In this study, we intend to realize an energy-efficient direct air capture process by making it into a fiber sorbent based on a physisorption-based solid adsorbent (physisorbent). The physisorbent not only captures a large amount of carbon dioxide, but can be easily regenerated at a relatively low temperature, and the fiber sorbent reduces pressure drop in the direct air capture process, enabling efficient adsorption/desorption. Through the combination of the physisorbent and fiber platform, we evaluate the energy efficiency of the process by estimating the total cycle time and regeneration temperature of the process.

O-D5: Demonstration of a post-combustion DR-VPSA CO2 capture pilot plant using solid adsorbents in Poland Izabela Majchrzak-Kucęba, Aleksandra Ściubidło, Dariusz Wawrzyńczak Czestochowa University of Technology, Department of Advanced Energy Technologies, Dabrowskiego Street 73, 42-201 Czestochowa, Poland, [email protected]

Abstract To achieve the climate goals towards the reduction of the emissions of carbon dioxide, decisive actions to reduce the CO2 emission must be taken by all sectors of the economy. The main emphasis in implementing the CCUS technology is being currently placed on the power generation sector, which is responsible for approximately 80% of the world's CO2 emissions from large stationary sources. With the intensive development of the absorption flue gas CO2 capture technique observed for many years, the adsorption post-combustion CO2 capture technique, one of the alternative methods which was previously regarded as having little chance of being commercialized, has been arousing increasing interest for several years. In Poland, tests on a demonstration pilot plant operating in adsorption VPSA technology have been conducted within Strategic Program. The mobile pilot pressure-swing flue gas

CO2 capture plant was connected to the flue gas pass of the supercritical fluidized- bed boiler in Łagisza Power Plant. The pilot-scale tests were preceded by laboratory and bench-scale tests, which enabled the selection of the appropriate procedures and sorbents for testing on a demonstration scale. The pilot DR-VPSA adsorption plant is a mobile unit. The pilot plant consists of four sections: a cooling and heat recovery section, a desulphurization and NOx removal section, a drying section, and CO2 capture unit. In the Łagisza Power Plant, due to the possibility of additional gas enrichment during the process, the Dual-Reflux Vacuum-Pressure Swing Adsorption (DR-VPSA) technique was employed, which had not been previously used for post- combustion CO2 capture on pilot scale in a conventional power plant in the world.

Acknowlegment This research has been supported by the project PPI/APM/2019/1/00042/U/00001 funded by Polish National Agency for Academic exchange NAWA and by the project BSPB-400-301/19.

O-D6: Decarbonising UK Steel Production: Pressure Swing CO2 Capture and Fuel Synthesis Challenges George R M Dowson, Isabel Tozer, Peter Styring, UK Centre for Carbon Dioxide Utilisation, Chemical & Biological Engineering, Sir Robert Hadfield Building, The University of Sheffield, Sheffield S1 3JD, UK SUSTAIN (Strategic University Steel Technology and Innovation Network)

As part of SUSTAIN (Strategic University Steel Technology and Innovation Network), we are developing the framework for a carbon capture system using above- atmospheric pressure swing, in collaboration with UK Steel producing partners. Post-capture, the prospects of subsequent fuel or other useful product synthesis is being investigated, to determine how a real-world CDU system can be operated at scale.

The SUSTAIN is a multidisciplinary group consisting of 6 major UK Universities, and 4 UK steel manufacturers with a collective production capacity of over 7 million tonnes per annum. Research themes cover CDU, reducing energy usage, recycling, smart processing, real-time analytics and product development.

Through this collaboration, and using the pressure swing capture and utilisation framework, we are developing a scalable, modular and flexible approach that can potentially fit with many kinds of CO2 point source, including those that are unsuitable for CCS and cannot otherwise be readily decarbonised. With industry collaboration, clear pictures of resource availability for carbon utilisation will allow for realistic prospects to be evaluated.

Initial aims include synthetic transport fuels as a utilisation product (for transport modes that cannot be readily electrified) which will be investigated under strict criteria that evaluate compatibility, reliability and economic & environmental viability.

References 1. Styring P, Dowson GRM & Tozer IO (2021) Frontiers in Energy Research, DOI: 10.3389/fenrg.2021.663331 O-D7: Tailored gas adsorption properties of electrospun carbon

nanofibers for CO2 capture and valorization A. Kretzschmar1,2, V. Selmert1,2, H. Weinrich1, H. Tempel1, H. Kungl1, R.-A. Eichel1,2, 1IEK-9, Forschungszentrum Jülich GmbH, Jülich, Germany 2IPC, RWTH Aachen, Aachen, Germany

Electrochemical reduction of CO2 using renewable energies is a promising way to reduce the amount of the greenhouse gas CO2 in the atmosphere. Simultaneously,

CO2 gas may act as a carbon feedstock for the chemical industry. The utilization of

CO2 in an electrolyzer requires prior capture of CO2 from its mixtures, for example flue gas or biogas in a pressure-swing adsorption process. A promising material are electrospun Polyacrylonitrile (PAN)-based carbon nanofibers, which exhibit not only excellent CO2 adsorption properties but also provide inherent electrical conductivity, possibly enabling to integrate CO2 capture and utilization in a single process. In our work, PAN-based nanofibers were prepared by electrospinning, stabilized in air and carbonized in Argon at various temperatures ranging from 600°C to 1100°C. On this material, static Ar, N2 and CO2 adsorption measurements have been performed in order to elucidate the gas adsorption properties and the influence of the carbonization temperature on the CO2 adsorption capacity and selectivity. Ideal adsorbed solution theory (IAST) calculations for the adsorption selectivity were performed by analyzing single component adsorption data of N2 and CO2.

Analyzing our data, a strong correlation between the CO2 adsorption capacities and the carbonization temperature was found, which was assigned to a change of the ultramicropore size distribution. Especially for low carbonization temperatures the

CNFs exhibit a very good low-pressure adsorption performance and excellent CO2/N2 IAST selectivities, which are attributed to extremely narrow ultramicropores. The observed CO2/N2 selectivity values represent some of the highest values for carbon materials ever reported in literature. Measurements with additional adsorptives such as methane and water provide evidence that the ultramicroporous carbon fibers can act as a molecular sieve, which can be tailored not only for the separation of CO2/N2, but also for other CO2 containing mixtures. O-D9: Impacts of nano-scale pore structure and organic amine

assembly in porous silica on the kinetics of CO2 adsorptive separation Feijian Lou1,2, Guanghui Zhang1, Limin, Ren2, Xinwen Guo1,* and Chunshan Song1,3,* 1State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China 2Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian 116024, China 3Department of Chemistry, Faculty of Science, the Chinese University of Hong Kong, Shatin, NT, Hong Kong, China E-mail: [email protected]; [email protected]

Figure 1 Schematic illustration of the structure-performance relationship of 50PEI-MSN, 2N-CSD and 50PEI-SBA15 sorbents. Effects of nano pore structure and amine assembly of amine functionalized solid sorbents on the sorption and desorption kinetics are investigated in the present work. 50PEI-MSN sorbent with inverted cone-shaped pores and 2N-CSD sorbent with arranged amine assembly are prepared. By comparison with 50PEI-SBA-15 sorbent, which has cylindrical pores and disordered amine assembly, both 50PEI-MSN and 2N- CSD sorbents have improved sorption and desorption kinetics. It shows that both kinetic and thermodynamic factors influence sorption and desorption kinetics. The tailoring of amine assembly makes thermodynamic factor dominate sorption, which is benefical for sorption at low temperature, While the tailoring of nano pore structure improves maximum sorption and desorption rates, thus benefiting sorption and desorption kinetics at high sorption temperature. The present work demonstrates the importance of tailoring nano pore structure and amine assembly for significantly improving sorption and desorption kinetics of adsorptive CO2 separation. References: [1] Feijian Lou, Guanghui Zhang, Limin Ren, Xinwen Guo, Chunshan Song. Impacts of nano-scale pore structure and organic amine assembly in porous silica on the kinetics of CO2 adsorptive separation. Nano research, 2021. (DOI: 10.1007/s12274-021-3609-3). O-D10: Rational Design of Solid Adsorbents for Post-Combustion

CO2 Capture via Temperature Swing Minkee Choi Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701, Korea.

Amine-functionalized porous materials have been extensively investigated as promising adsorbents for post-combustion CO2 capture due to their chemisorption ability of low-concentration CO2 (ca. 15%) from a wet flue gas. However, earlier studies in academia have mainly focused on the improvement of CO2 uptake of the adsorbents and there have been rather limited studies on other important aspects for adsorbents such as regenerability, long-term stability, cost, and scalability of material production. In the present work, I will disclose our recent progresses on the adsorbent development for post-combustion CO2 capture, which was supported by Korea CCS R&D Center (KCRC). In this research consortium, we developed a cost-effective and scalable synthesis method for amine/silica composite adsorbents that can simultaneously show large CO2 working capacities as well as outstanding stability (e.g., hydrothermal stability, urea stability, oxidation stability) in a practically meaningful temperature swing adsorption (TSA) condition (adsorbent regeneration under 100%

CO2 at 110–120 ˚C). It will be demonstrated that controlled modification of polyethyleneimine (PEI) with epoxide-derivatives can markedly reduce the heat of

CO2 adsorption and facilitates CO2 desorption compared to unmodified PEI during the adsorbent regeneration. The modification also significantly increased long-term adsorbent stability over repeated TSA cycles due to remarkable suppression of CO₂- induced urea formation and oxidative amine degradations.

References 1. W. Choi, et al., Nature Communications, 2016, 7, 12640 2. K. Min, et al., ChemSusChem, 2017, 10, 2518 3. K. Min, W. Choi, C. Kim, M. Choi*, Nature Communications, 2018, 9, 726 4. K. Min, W. Choi, C. Kim, M. Choi*, ACS Appl. Mater. Interfaces 2018, 10, 23825 O-D11: Scalable Metal-Organic Frameworks in Open-Porous Polymeric Contactor for Carbon Capture

Young Hun Lee1, Aqil jamal2, Dong-Yeun Koh1,* 1Department of Chemical and Biomolecular Engineering, KAIST, Daejeon 34141, Korea 2Carbon Management Research Division, Research & Development Center, Saudi Aramco, Dhahran 31311, Kingdom of Saudi Arabia, * Corresponding author E-mail: [email protected]

Metal-organic framework (MOF) is a class of microporous materials that have been highlighted with fast and selective sorption of gas molecules, however, they are at least partially unstable in the scale-up process. In CO2 capture field, metal organic frameworks (MOFs) as solid sorbents are attracting attention as materials which have not only a high specific surface area due to its microporous property, but also an excellent CO2 adsorption capacity because they are physisorbents. Although MgMOF- 74 which is one of the top performing MOFs has 8 mmol/g @ 298K and 1 bar, the

MOF loses CO2 adsorption capacity up to 80% under humid conditions. Recently, amine-functionalized adsorbents are effective for CO2 capture at low CO2 partial pressures and can be stabilized in water via decoration with amine group on the open metal site of MOFs. In addition, fiber matrix can possess high loading of adsorbent and good mass transfer rate. Here, we report a rational shaping of amine functionalized metal-organic frameworks in a scalable architecture of fiber sorbent. The long-standing stability challenge of the MOFs was resolved by using the stable metal oxide precursors that are subject to controlled surface oxide dissolution-growth chemistry during the Mg-based MOF synthesis. Highly uniform MOF crystals are synthesized along with the open-porous fiber sorbents networks, showing unprecedented cyclic CO2 capacities in both flue gas and direct air capture (DAC) conditions. The same chemistry enables an in-situ flow synthesis of Mg-MOF fiber sorbents, providing a scalable pathway for MOF synthesis in an inert condition with minimal handling steps. This modular approach can serve both as a reaction stage for enhanced MOF fiber synthesis as well as a “process-ready” separation device.

O-D12: Improved performance of modified CaO-Al2O3 pellets for

CO2 capture under realistic Ca-looping conditions Ismail Mohamed, Paula Teixeira, M. Carmen Bacariza, Carla I.C. Pinheiro CQE–Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Avenida Rovisco Pais 1, 1049-001 Lisboa, Portugal Abstract Recently, significant progress in carbon capture technologies has been achieved with 1 cost reduction being one of the most relevant goals . Among the post-combustion CO2 capture technologies, the Ca-looping (CaL) represents a promising solution mainly due to the CaO high CO2 adsorption capacity (0.78 g CO2/g CaO), high selectivity and to the possibility of using natural inexpensive sorbents and wastes that can be used as raw materials for the cement production after deactivation. Sorbent deactivation imposes a limitation due to sintering and pore blockage with cycles progression. Utilization of inert additives such as solid industrial waste resources was recently proposed to enhance the CaL sorbents’ sintering resistance by preventing CaO particles agglomeration2. In this work, four modified CaO-based sorbents were prepared by incorporation of Al2O3 as a stable structural support, in natural wastes of marble, with different molar ratios. CaO-Al2O3 pellets with particle sizes in the range 355-500µm were prepared by extrusion followed by granulation. The performance of these aluminum-supported CaO-based pellets was evaluated for CO2 capture in a laboratory scale fluidized bed reactor along 10 carbonation-calcination cycles. The sorbent pellets were tested over 10 cycles of carbonation (at 700°C and 25% CO2 in air mimicking the concentration of CO2 from cement plant’s flue gas) and calcination

(at 930°C and 70% CO2 in air). The pellets’ mechanical strengths against fragmentation and elutriation were also evaluated. The modified CaO-Al2O3 sorbents were characterized by N2 adsorption technique and by powder X-ray diffraction. The results show that the addition of Al2O3 as a structural support in CaO-based sorbents, significantly improves the performance and stability of the natural wastes of marble without incorporation of Al2O3 along the carbonation-calcination cycles. This allows for reduced sorbent make-up frequency and cost reduction.

1 Global CCS institute, 2016. The Global Status of CCS 2016 Summary Report. 2 P. Teixeira, I. Mohamed, A. Fernandes, J. Silva, F. Ribeiro, C.I.C. Pinheiro. Separation and Purification Technology, 2020: 116190. O-D13: Insights of the mechanochemical processof the CO2 conversion driven by olivine powders structural evolution G.Mulas, S.Garroni, S.Enzo, M.D.Simula, A.Taras Department of Chemistry and Pharmacy, University of Sassari, 07100 Sassari, Italy

The chemical weathering of silicate-based minerals is a natural process able to offer a mitigation action, over geological timescales, with respect to atmospheric CO2 concentration values. Ca, Mg and Fe Carbonates, main products of chemical weathering, can be also subjected to subsequent reduction paths under specific conditions, leading to CO2 evolution products, worthy of potential interest in agreement with CCUS strategies. The involved chemical processes are thermodynamically favoured, but kinetic constraints appear as a severe limitation in view of wide scale application of the natural process. Moreover, recent results of research activity on a lab scale suggest that, while the activation of such process by conventional thermal treatment requires severe conditions, conversely, the use of external mechanical energy allows to successfully improve the reaction kinetics under mild conditions. Along this line, in the present work we addressed our attention to the CO2 activation process carried out in presence of Olivine and H2O, under the input of mechanical treatment, using the suitably modified grinding jar as a mechanochemical reactor, operating either as a batch type reactor and as a flow one. Fast kinetics and high conversion values characterize the process, occurring at room temperature and atmospheric pressure. Different instrumental techniques were employed in order to characterize the solid phases and gaseous systems, as well as to analyse the relative transformations during the chemical processes in order to gain insights of the reaction mechanism. The reconstruction of the solid phases with the formation of Mg carbonates accompanied the reduction of CO2 in the gaseous phase, with high selectivity to methane, and the specific results were observed to depend on the different adopted experimental condition.

Acknowledgments The present work has been funded within the MSCA- RISE action, CO2MPRISE (G.A. 734873). O-D15: Molecular simulation study of CO2/H2O competitive adsorption on all-silicon zeolites

Jie Zhaoa,b, Shuai Denga,b,*, Li Zhaoa, Xiangzhou Yuanc, Zhenyu Dua,b, Shuangjun Lia,b , Lijin Chena,b, Kailong Wua,b

a Key Laboratory of Efficient Utilization of Low and Medium Grade Energy (Tianjin University), MOE, Tianjin University, Tianjin 300072, China

b International Cooperation Research Centre of Carbon Capture in Ultra-low Energy-consumption

c Department of Chemical and Biological Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02831, Republic of Korea

* Corresponding author. Tel: 86-022-27404188; Fax: 86-022-27404188. E-mail: [email protected] (S. Deng).

The presence of water vapor in realistic flue gas should be emphasized in the development of adsorbents for post-combustion CO2 capture. However, the co- adsorption mechanisms of H2O and CO2 molecules on adsorbents are still unclear. In this work, the adsorption performance and the competitive mechanism of a

CO2/H2O binary mixture were investigated through molecular simulation. A proper force filed of H2O was identified among SPC/E, TIP4P, and TIP5P models. The adsorption isotherms of CO2, H2O, and CO2/H2O on all-silicon zeolites were obtained by Grand Canonical Monte Carlo (GCMC) simulations from 300 K to 400 K. The

CO2/H2O selectivity was obtained digitally to indicate the competitive adsorption behavior. The adsorption entropy and the adsorption enthalpy were derived according to the statistical thermodynamics. Simulated equilibrium isotherms showed that the presence of small amount of H2O in the gas mixture had a significant impact on the adsorption loadings of CO2 in all-silicon zeolite. Detailed thermodynamics analysis demonstrated the adsorption entropies and enthalpies had a temperature dependence and they would switch the relative order of Gibbs free adsorption energy between adsorbed CO2 and H2O. This work will provide a guidance to explain the co-adsorption behaviors of CO2 and H2O from the perspective of thermodynamics.

O-D16: Novel VOCs recovery system using CO2 and NH3 as refrigerants with cascade condensation

Ki Heum Park, Yutaek Seo*

a Department of Naval Architecture and Ocean Engineering, Research Institute of Marine Systems Engineering, Seoul National University, Seoul, Republic of Korea, Seoul 151-744, Republic of Korea

Volatile Organic Compounds (VOC) are organic substances that evaporate from crude oil. More than five million tonnes of VOCs are emitted during the transport of crude oil or oil-related substances by various sea routes. It is suggested that the VOCs are most generated when crude oil is loaded into a ship. About 0.08 ~ 0.15 % of the crude oil loaded into the ship is released as VOCs, which indicates that 50 ~ 200 tons of VOC are generated per loading. Methane, one of gaseous components of VOCs, has a greenhouse effect of 21 times higher than carbon dioxide, and non-methane VOCs (nm VOC) may react with nitrogen oxides and produces ozone. Therefore, the recovery of VOCs generated by crude oil loading is central to avoid any environmental issues. Industrial approaches to recover VOCs include absorption, adsorption, membrane, and condensation techniques. In this study, we developed the VOCs recovery process based on the selective condensation of VOCs. The process consists of two stages. In the first stage, condensation through seawater is carried out and two streams of gas and liquid streams are obtained. Then, the condensed liquid stream, called LVOC, is recovered and stored as a propulsion fuel, while the gas stream is transported to the second stage of condensation using propylene refrigerant.

The process was modeled using Aspen HYSYS V10, and then we investigated CO2 to replace propylene refrigerant in the second stage of condensation, due to its explosive nature. When CO2 is used as a single refrigerant, the pressure of the refrigerant cycle becomes high resulting decreased efficiency. Therefore, ammonia, which does not have explosiveness and a greenhouse effect, and R134a, which is mainly used as a refrigerant, are also analyzed as a refrigerant. To evaluate the process performance, COP was analyzed when changing the refrigerants like a mixture of carbon dioxide and each refrigerant, and modifying the design of the process such as cascade refrigeration or auto-cascade refrigeration. The obtained results suggested that the mixed refrigerant was not suitable because of its low efficiency and high operating pressure. However, the cascade refrigeration showed low operating pressure and high efficiency, although it requires two compressors. The auto-cascade refrigeration can be operated with one compressor, but with lower process efficiency. Better process type would be selected with through economic evaluation coupled with ship energy systems. O-F1: Power-to-X Technologies, Part of a Sustainable Industrial Ecosystem Thomas Ernst Müller Carbon Sources and Conversion, Faculty of Mechanical Engineering, Ruhr-Universität Bochum, Bochum, Germany The dynamic flow pattern of carbonaceous compounds through the diverse geo- habitats on earth has been undermined through the magnitude fossil resources are industrially exploited as energy source and for material applications [1]. The resulting accumulation of carbon dioxide (CO2) in the atmosphere has resulted in evident changes in climate. To mitigate the effects, renewable primary energy sources need to be integrated to an increasing degree into forthcoming sustainable industrial ecosystems. In form of the sustainability goals of the United Nations this has been recognised as one of the grant challenges of mankind.

Fig. 1: Possible role of Power-to-X technologies in a forthcoming sustainable industrial ecosystem Many of the sustainable primary energy sources, such as wind and solar energy, are intrinsically fluctuating in their availability. For balancing the spatial and temporal disbalances arising between supply and demand Power-to-X (PtX) technologies are considered a promising option. PtX comprises converting primary energy, mostly electricity, into alternative energy sources that can be stored, transported and utilized at another time than they are produced [2]. Likewise, PtX offers the opportunity of making carbon-based chemical entities available as raw material to the chemical industry that are not based on fossil resources. In the lecture, it will be analysed how PtX technologies can contribute to establishing sustainable industrial ecosystems. References: [1] P. Tomkins; T. E. Müller; Evaluating the Carbon Inventory, Carbon Fluxes and Carbon Cycles for a Long-term Sustainable World; Green Chem. 21 (2019) 3994. [2] M. Hermesmann, K. Grübel, L. Scherotzki, T. E. Müller; Promising pathways: The Geographic and Energetic Potential of Power-to-X Technologies based on Regeneratively Obtained Hydrogen; RSER, 138 (2021) 110644. O-F2: Transport Fuels from CO2: Avoiding a Social Underclass in a Just Energy Transition Peter Styring, George RM Dowson, Edward G Platt, Emily L Duckworth, Isabel Tozer UK Centre for Carbon Dioxide Utilisation, Chemical & Biological Engineering, Sir Robert Hadfield Building, The University of Sheffield, Sheffield S1 3JD, UK

A Theory of Change approach has been applied to identify gaps and hotspots in a transition to Net Zero in the transport sector. In particular, we focus on the role Power to X, (PtX) liquid synthetic fuels derived from carbon dioxide and renewable power, can be applied together with a shift to battery electric vehicles (BEVs) to not only achieve but accelerate the path towards net zero.1 PtX fuels can be used to replace fossil carbon-based fuels in legacy internal combustion engine (ICE) vehicles and hybrids, while an ongoing move to BEV fleets in supported. The use of PtX fuels will be considered in relation to a systemic life cycle assessment including vehicle production, in-use emissions and end of life emissions in a range of vehicle types.2 Furthermore, we will discuss the consequential impacts of the fuel transition, considering social impacts of fuel switching and the effects on air quality as a new regime of low CO2, SOx and NOx emissions is implemented. This will include dynamic emissions monitoring using the CoVid-19 lockdowns as a window into a low emissions future. Recommendations will be made on how carbon dioxide utilisation in PtX fuels can be used to implement realistic policy interventions while recognising that legacy ICEs will play a major role in social mobility on the road to net zero.

References 1. Styring P & Dowson GRM (2021). Johnson Matthey Technol. Rev., 65 170-179. 2. Ellingsen LA-W, Singh B & Strømman AH (2020). Environ. Res. Lett. 11 054010. 3. Styring P, Dowson GRM & Tozer IO (2021) Frontiers in Energy Research, DOI: 10.3389/fenrg.2021.663331

O-F3: Life cycle assessment for CO2-methanol conversion processes with annual grid electricity of Republic of Korea

Seung Gul Ryoo1, 2, Han Sol Jung1, 2, Yong Tae Kang1, 2

1School of Mechanical Engineering, Korea University, Seoul, Republic of Korea;

2Center for Plus Energy Building Innovative Technology, ERC, Seoul, Republic of Korea

Research on CO2 conversion to other valuable compounds has been extensively paid attention, and photocatalytic conversion is noted for significance on energy conservation during the conversion process. In this study, methanol is selected as the product of CO2 conversion for wide applications, such as chemical feedstock and fuel for combustion or fuel cell, providing sufficient market size and value. Upon selected process and product, life cycle assessment is performed to evaluate the environmental impacts of CO2- methanol production via photocatalytic conversion. In addition, annual power generations of Republic of Korea are considered to depict annually transitioning grid electricity, and its effect on application to the conversion system. In this research, photocatalytic conversion process from recently published literature has been selected for the analysis, and coal gasification conversion process is selected for comparision [1]. To show the envrionmental impact change, namely global warming potential upon application, grid electricty of Korea has been applied to the conversion system. Furthermore, annual power generation data from 2018-2020 are formulated into the grid electricity unit to show the shifting power generation trend in Korea [2]. The reduction of global warming potential of two different CO2-methanol production routes by the transitioning grid electricity is observed, and entailed alleviating and aggravating environment impacts are evaluted. In addition, possibility of zero-emission is evaluated with renewable energy sources.

References [1] Ryoo, S. G., Jung, H. S., Kim, M., & Kang, Y. T. (2021). Bridge to zero-emission: Life cycle assessment of CO2–methanol conversion process and energy optimization. Energy, 120626. [2] Korea Electric Power Corporation, The Monthly Report on Major Electric Power Statistics. 2020. vol. 495-506. Korean government publication registration number: 2020-9721-0022.

O-F4: Comparative Evaluation of the Power-to-Methanol Process Configurations and Assessment of Process Flexibility and Techno- Economics under Uncertainty

Siphesihle Mbathaa*, Raymond C. Eversonb*, Nicolaas Engelbrechtc, Nicholas M. Musyokaa, Henrietta W. Langmid, Dmitri Bessarabovc, Andrea Lanzinie, Mike Dryf

a HySA Infrastructure Centre of Competence, Centre for Nanostructures and Advanced Materials (CeNAM), Chemicals Cluster, Council for Scientific and Industrial Research (CSIR), Pretoria 0001, South Africa b Center of Excellence in Carbon Based Fuels, School of Chemical and Minerals Engineering, Faculty of Engineering, North-West University, Private Bag X6001, Potchefstroom, 2531, South Africa c HySA Infrastructure Centre of Competence, North-West University, Faculty of Engineering, Private Bag X6001, Potchefstroom, 2531, South Africa d Department of Chemistry, University of Pretoria, Private Bag X20, Hatfield, 0028, South Africa e Department of Energy (DENERG), Politecnico di Torino, Corso Duca Degli Abruzzi, 24, 10129, Turin, Italy. f ARITHMETEK Inc., 1331 Hetherington Drive, Peterborough, Ontario K9L 1X4, Canada *Correspondence Emails: [email protected] (Siphesihle Mbatha), [email protected] (Raymond C. Everson), [email protected] (Nicholas M.Musyoka).

Abstract This paper compares different power-to-methanol process configurations encompassing electrolyser, reactor(s) and methanol purification configurations. Eight different power-to-methanol configurations based on direct CO2 hydrogenation with H2 derived from H2O-electrolysis were generated, modelled, compared and analysed. High temperature solid oxide electrolyser(s) is used for hydrogen production. Fixed bed reactor(s) is used for methanol synthesis. The aim of the paper is to give detailed comparison of the process layouts under similar conditions and select the best performing process configuration considering overall methanol production, CO2 conversion, capital and production costs, and energy efficiency. ASPEN PLUS® V8.6 is used for flowsheet modelling and the system architectures considered are the open loop systems where methanol is produced at 100 kton/annum and sold to market as the final purified product. Further optimization requirements are established as targets for future work. Candidate(s) for power-to-methanol configuration(s) with methanol synthesis from CO2 hydrogenation is proposed and further evaluated considering process flexibility and techno-economics under uncertainty conditions. Using the best performing configuration, the study further extends to quantitatively and comparatively answer the question on which electrolysis technology is promising for power-to- methanol considering high temperature solid oxide, alkaline water-based and polymer exchange membrane electrolyser technologies for hydrogen production and taking into account the experience rate (i.e. learning-by-doing) effects.

Key words: Power-to-Methanol system configurations, process design, process integration, electrolyser, techno-economics, uncertainty, Monte-Carlo

O-F5: The “Making Sense of Techno-Economic and Life Cycle

Assessment studies for CO2 Utilization” Report: an update Lorenzo Cremonese, Till Strunge, Barbara Olfe-Kräutlein, Stephen McCord, Tim Langhorst, Yuan Wang

a CO2 Utilization and Society, Institute for Advanced Sustainability Studies (IASS), Potsdam, Germany b Department of Chemical and Biological Engineering, University of Sheffield, Sheffield, UK c Energy and Process Systems Engineering, ETH, Zurich, Switzerland d Institute for Chemistry, Technical University Berlin (TUB), Berlin, Germany Understanding the environmental impacts and economics of CCU routes is essential for decision makers from relevant fields, such as technology developers, entrepreneurs, funding agencies, policy makers, administrators and more, to make decisions in line with sustainability strategies, and to discard inappropriate solutions.

If from one side guidelines on how to perform TEA and LCA for CO2 utilization technology for practitioners are emerging, on the other policy officers at national and international levels have frequently signaled the urgency of also providing guidance on how to make use of this technical knowledge in decision making processes and policy design. There is in fact a risk of insufficient transfer into policy or other decision- making processes, in cases where the involved actors do not possess disciplinary expertise in the relevant methodology. To ensure that disciplinary expertise is effectively taken up by decision makers and all potential audiences, including policy makers, the CO2nsistent project funded by the

Global CO2 Initiative and EIT Climate-KIC published the Making Sense of TEA and LCA Studies report. It provides user-centered guidance on how to commission and understand TEA and LCA studies for CCU, and how to determine whether existing studies are eligible to be used in a decision-making process. This is particularly relevant to actors in all types of public and private organizations involved in the planning and development of CCU, and is based on the published TEA and LCA Guidelines for CO2 Utilization1. The CO2nsistent team is currently working on an updated version of this report that will be presented during the conference, before being published in early 2022.

1 Techno-Economic Assessment & Life Cycle Assessment Guidelines for CO2 Utilization, 2020. GCI. Available at: https://deepblue.lib.umich.edu/handle/2027.42/162573. O-F6: Methanol Synthesis Process with CO2-rich Natural Gas Fields: Techno-economic Analysis Seungwoo Kim1, Yoori Kim2, Se-Young Oh2, Myung-June Park3,4, Won Bo Lee1 1School of Chemical and Biological Engineering, Seoul National University, Seoul, Republic of Korea 2Advanced Research Center, Korea Shipbuilding & Offshore Engineering, Seoul, Republic of Korea 3Department of Chemical Engineering, Ajou University, Suwon, Republic of Korea 4Department of Energy Systems Research, Ajou University, Suwon, Republic of Korea

Natural gas fields with high CO2 concentration are considered to be economically infeasible if a conventional treatment procedure is applied due to the large amount of energy and cost required for complete separation of CO2 and relatively little amount of CH4. As an alternative means of efficiently developing the CO2-rich gas fields, one of CO2 utilization, methanol synthesis was considered in the present study. To remove

H2S in natural gas completely, an acid gas removal unit (AGRU) was used, and two different amine absorbents were compared to control the CO2 removal rate. Methyl- diethanolamine (MDEA) resulted in a sweet gas with a larger amount of CO2 than CH4, while a mixture of MDEA and diethanolamine (DEA) led to the stoichiometric ratio of

CH4 and CO2 for dry reforming. To compensate for the insufficient amount of H2 for methanol synthesis, water was additionally supplied to enhance steam reforming reaction, increasing the methanol productivity. The recycle of unreacted gas was compare to the open-loop case in the methanol synthesis process, and the methanol production rate increased despite the decrease of local conversions of CO and CO2 due to the shortage of H2 in the recycle stream. The techno-economic analysis was applied to calculate return on investment (ROI) and payback period (PBP) as economic factors for all the cases, the results showed that the direct utilization of CO2 for the production of methanol might be an economically feasible method for the natural gas fields with high CO2 concentration. Further analysis showed there exists a tradeoff between methanol production and the cost for steam generation, indicating an optimal amount of feedwater should be supplied to maximize profitability.

O-F7: Is there a business case for CO2 mineralisation in the cement industry? Till Strunge1,2 1Institute for Advanced Sustainability Studies e.V., Potsdam, Germany 2Research Centre for Carbon Solutions, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, UK

Being among the biggest emitters of anthropogenic CO2, the cement industry requires 1 affordable pathways towards a sustainable future . CO2 mineralisation routes could potentially contribute to this direction. Hereby, CO2 is reacted with activated minerals to form carbonates 2. These resulting carbonates could potentially be used for multiple purposes, such as fillers, cement additives or for land reclamation projects 3. Some policy advice reports use the CO2 mineralisation as positive examples for the successful utilisation of CO2 as a feedstock, because unlike most other CCU concepts, the carbonation reaction is energetically favoured 4. Since major hurdles for implementing CCU technologies, including CO2 mineralisation pathways, are often 5 their economic viability , assessments of business cases using CO2 mineralisation are needed. In this contribution, we present through integrated techno-economic modelling how potential business cases for CO2 mineralisation in the cement industry could be achieved. Moreover, we use state of the art uncertainty analysis tools to shed light on the circumstances under which these novel technologies can become economically viable. Understanding the economics of CCU technologies is essential for their further development as well as deployment and can help decision makers to derive feasible sustainability strategies.

References 1 Favier, A., De Wolf, C., Scrivener, K. & Habert, G. A sustainable future for the European Cement and Concrete Industry: Technology assessment for full decarbonisation of the industry by 2050. (ETH Zurich, 2018). 2 Sanna, A., Uibu, M., Caramanna, G., Kuusik, R. & Maroto-Valer, M. M. A review of mineral carbonation technologies to sequester CO2. Chem Soc Rev 43, 8049-8080, doi:10.1039/c4cs00035h (2014). 3 Sanna, A., Hall, M. R. & Maroto-Valer, M. Post-processing pathways in carbon capture and storage by mineral carbonation (CCSM) towards the introduction of carbon neutral materials. Energy & Environmental Science 5, 7781, doi:10.1039/c2ee03455g (2012). 4 WWF Deutschland. Wie klimaneutral ist CO2 als Rohstoff Wirklich? - WWF Position zu Carbon Capture and Utilization (CCU). (2018). 5 Zimmermann, A. et al. CO2 utilisation today: report 2017. (2017).

O-F8:Toward carbon-neutral cement industry via CO2 mineralization

Hesam Ostovari a, Leonard Müller a, André Bardow a,b,c

a Institute of Technical Thermodynamics, RWTH Aachen University, Germany

b Institute of Energy and Climate Research - Energy Systems Engineering (IEK-10), Forschungszentrum Jülich GmbH, Jülich, Germany

c Energy & Process Systems Engineering, ETH Zürich, Switzerland The IPCC special report requires that global anthropogenic greenhouse gas (GHG) emissions need to become zero and even negative to limit the negative impacts of climate change. 7% of global GHG emissions (2.2 Gt CO2e/year in 2014)1 are due to the cement industry. As half of the cement emissions are process-inherent, CO2 mitigation for the cement industry is currently mostly approached by carbon capture and storage. Carbon capture and storage is also possible by CO2 mineralization that not only permanently stores CO2 but also yields products, which can potentially substitute cement.2 Hence, combining CO2 mineralization and cement production can potentially mitigate GHG emissions via two mechanism: a) capturing and storing CO2 from the cement plant, b) reducing clinker use by substituting cement. However, indirect emissions are caused by energy and material demands for CO2 capture and to overcome the slow reaction kinetics of mineralization. To assess the potential of combining CO2 mineralization and cement production for GHG mitigation, a systematic assessment of GHG emissions along the full life cycle is needed. In this work, we assess the GHG mitigation potential of combining CO2 mineralization and cement production. From the assessment of three potential combinations, we derive the potential for carbon-neutral cement. Our results show that combined CO2 mineralization and cement production can reduce the GHG emissions of cement beyond the potential of previous approaches. The largest GHG reduction is obtained by combining carbon capture & storage with clinker usage reduction. The GHG reduction ranges from 44% to 86% for today’s energy mix. With availability of clean energy or possibility of high blended fractions, combined CO2 mineralization and cement production could produce carbon-neutral or even carbonnegative cement. Thus, our results suggest that developing the processes and the products of combined CO2 mineralization and cement production is highly desirable to reduce GHG emissions in the cement industry. References 1 IEA, Technology Roadmap Low-Carbon Transition in the Cement Industry, 2018. 2 V. Romanov, Y. Soong, C. Carney, G. E. Rush, B. Nielsen and W. O’Connor, ChemBioEng Reviews, 2015, 2, 231–256, http://dx.doi.org/10.1002/cben.201500002. Acknowledgement: this work was performed as part of project “CO2MIN” (033RC014), funded by the German federal ministry of education and research O-F9: Carbon dioxide utilisation by mineral carbonation with the use of fly ashes Aleksandra Ściubidło, Izabela Majchrzak-Kucęba Department of Advanced Energy Technologies, Faculty of Infrastructure and Environmental, Czestochowa University of Technology, Częstochowa, Poland

CO2 is believed to be the main cause of the greenhouse effect, and a large part of the increase in CO2 in the atmosphere is from the burning of fossil fuels. Carbon capture, utilisation and storage (CCUS) from flue gases has been considered as a key measure to reduce this effect in the short term. Therefore, the development of cost-effective techniques for the utilization of CO2 is considered to be one of the highest priorities in CCUS.

Mineral carbonation is a process whereby CO2 is chemically reacted with calcium- and/or magnesium-containing minerals and is a potentially attractive utilisation technology for the permanent and safe storage of CO2. The alkaline industrial waste, such as fly ash can also be considered as a source of calcium or magnesium.

In this paper, we have reviewed the literature on mineral carbonation of CO2 with the use of fly ashes and assessed the progress in the research and developments in this direction.

O-F11: CO2 as sustainable carbon source Pathways for industrial

application (CO2-WIN) Dipl.-Ing. Dennis Krämer 1 , DECHEMA Gesellschaft für Chemische Technik und Biotechnologie e.V.1

The chemical industry is a major supplier for a wide range of industries. Since the primary carbon sources of the chemical industry is of fossil origin, everyday products such as plastics, cosmetics, or even medicines are predominantly made from crude oil or natural gas. In order to reduce the overdependence of the chemical value chain on unsustainable resources the German Federal Ministry of Education and Research (BMBF) started a major research program to utilize carbon dioxide as an alternative and sustainable carbon source in 2010. This first specialized funding measure for CO

2 utilization has demonstrated the great potential of these technologies for decreasing the CO2 footprint of chemical processes bus also for finding more sustainable raw materials to produce plastics and fuels. Since then, the BMBF continuous to suppert project on CO2 utilization. 2020, the funding measure “CO2 as sustainable carbon source pathways to industrial application (CO2-WIN) started. Under the funding measure, 14 industry driven R&D projects on chemical and biochemical CO2 conversion, photo and electrocatalysis and CO2 mineralisation are funded. utilization has moved on from a vision to a reality. DECHEMA is coordinator of the supporting and scientific coordination project CO2-WIN Connect . The project includes research with respect scientific analysis on the overall potential in respect to lower CO2 emissions and save fossil resources as well as pushing forward to develop standards in the field of CO2 utilization processes The presentation at ICCDU 2021 would include insights of the funding measure and the latest information about other German R&D programmes on the topic.

O-F12: Environmental and Economic Assessment of International

Production Locations for CO2-based Chemicals Simon Kaiser, Katharina Prontnicki, Stefan Bringezu University of Kassel, Kassel, Germany

The utilization of CO2 in combination with renewable energy and water is a promising alternative for the use of fossil hydrocarbons in the chemical industry. In countries like Germany, the required amounts of renewable energy for a large-scale production will most probably exceed their availability.

To gain more information about the environmental impacts and economic parameters of a potential import of CO2-based chemicals, 19 representative international production locations were identified considering energy, CO2, and water availability in more than 11.000 possible regions and compared to 2 locations in Germany. Life cycle and economic assessments were done for all locations for CO2-based methanol and naphtha.

The results show that location-differences determine environmental impacts and economic parameters with a tendency of wind-based locations outperforming those using photovoltaic cells. Comparing both chemicals, methanol shows better results in every category with the examined German locations showing promising results. While a decrease of the climate footprint can be reached for both chemicals at all locations in relation to the conventional alternatives, they also show a trade-off between the climate footprint and at least two other environmental impacts which raises the risk of problem shifting. A viable production might require additional policy support for most of the production locations. However, the inclusion of chemicals into carbon pricing schemes may either not be sufficient or not necessary. The calculated break-even carbon prices for methanol range from 178 €/t CO2 to 1.618 €/t CO2 in the status quo and from –51 €/t CO2 to 954 €/t CO2 in 2030. Importantly, desalination of water did not significantly raise the environmental impacts or production costs. Therefore, it might be promising to develop production plants in regions with very good conditions for renewable energy production while planning to use saline water to avoid additional pressure on water systems. O-F13: TRL-based comprehensive procedure for early-stage

evaluation of emerging CO2 utilization technologies Kosan Roh1,2, André Bardow6,4,7,9, Dominik Bongartz1, Jannik Burre1, Wonsuk Chung3, Sarah Deutz4, Dongho Han3, Matthias Heßelmann5, Yannik Kohlhaas5, Andrea König1, Jeehwan S. Lee3, Raoul Meys4, Simon Völker4, Matthias Wessling5,8, Jay H. Lee3,*, Alexander Mitsos6,1,7,* 1Process Systems Engineering (AVT.SVT), RWTH Aachen University, Aachen, Germany 2Department of Chemical Engineering and Applied Chemistry, Chungnam National University, Daejeon, Republic of Korea 3Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea 4Institute of Technical Thermodynamics (LTT), RWTH Aachen University, Aachen, Germany 5Chemical Process Engineering (AVT.CVT), RWTH Aachen University, Aachen, Germany 6JARA-ENERGY, Aachen, Germany 7Energy Systems Engineering (IEK-10), Jülich, Germany 8DWI-Leibniz Institute for Interactive Materials, Aachen, Germany 9Department of Mechanical and Process Engineering, ETH Zurich, Zürich, Switzerland

Abstract

CO2 utilization (CDU) has attracted much attention in both industry and academia due to its potential to mitigate greenhouse gas (GHG) emissions while potentially 1,2 generating economic benefits . Most emerging CO2 utilization technologies still remain at low technology readiness levels (TRLs)3 except a few cases, e.g., the production of methanol4, polyol5, and synthetic methane and liquid fuel6,7. Given the large number of potential CDU technologies, successful early-stage evaluation can identify promising ones to guide R&D investments. Thereby, overall cost can be reduced drastically since large-scale experiments and demonstration at higher TRLs are by far the highest cost components in process development, which can be prevented for non-promising technologies8. However, key challenges of early-stage evaluation are the limited availability and uncertainty of data9 and also the need for a consistent selection of performance indicators that are addressed in this contribution. We propose a systematic and comprehensive procedure for the early-stage evaluation of emerging CDU technologies10. More specifically, we employ the TRL scale and focus on TRL 2–4. The procedure consists of three steps: 1. data preparation, 2. data calculation, and 3. performance indicator calculation. The performance indicators are grouped into five categories: material, energy, GHG reduction, economics, and combined GHG reduction and economics. The procedure also depends on the type of

CDU technology, namely, thermochemical, electrochemical, and biological CO2 conversion. We demonstrate the proposed procedure on electrochemical production of ethylene11,12, which is studied as if it were at TRL 2, 3, and 4. We conceptually design the ethylene production process (for the analysis at TRL 4) and calculate the performance indicators to discuss how the evaluation outcomes evolve with increasing TRL. We finally point out that the accuracy of the performance indicators at TRL 2 and 3 strongly depends on what type of energy is supplied to the entire CDU system and how much of the CDU product can be recovered in reality. Reference 1 A. Kätelhön, R. Meys, S. Deutz, S. Suh and A. Bardow, Climate change mitigation potential of carbon capture and utilization in the chemical industry, Proc. Natl. Acad. Sci., 2019, 116, 11187–11194. 2 K. Roh, A. S. Al-Hunaidy, H. Imran and J. H. Lee, Optimization-based identification of CO2 capture and utilization processing paths for life cycle greenhouse gas reduction and economic benefits, AIChE J., 2019, 65, e16580. 3 A. W. Zimmermann and R. Schomäcker, Assessing Early-Stage CO2 utilization Technologies— Comparing Apples and Oranges?, Energy Technol., 2017, 5, 850–860. 4 Carbon Recycling International, Carbon Recycling International, http://www.carbonrecycling.is/, (accessed 6 June 2018). 5 N. von der Assen and A. Bardow, Life cycle assessment of polyols for polyurethane production using CO2 as feedstock: insights from an industrial case study, Green Chem., 2014, 16, 3272. 6 Sunfire GmbH, Sunfire - Syngas, https://www.sunfire.de/en/, (accessed 9 June 2018). 7 S. Rönsch, J. Schneider, S. Matthischke, M. Schlüter, M. Götz, J. Lefebvre, P. Prabhakaran and S. Bajohr, Review on methanation – From fundamentals to current projects, Fuel, 2016, 166, 276–296. 8 A. Zimmermann, J. Wunderlich, G. Buchner, L. Müller, K. Armstrong, S. Michailos, A. Marxen, H. Naims, F. Mason, G. Stokes and E. Williams, Techno-Economic Assessment & Life-Cycle Assessment Guidelines for CO2 Utilization, 2018. 9 K. Ulonska, M. Skiborowski, A. Mitsos and J. Viell, Early-stage evaluation of biorefinery processing pathways using process network flux analysis, AIChE J., 2016, 62, 3096–3108. 10 K. Roh, A. Bardow, D. Bongartz, J. Burre, W. Chung, S. Deutz, D. Han, M. Heßelmann, Y. Kohlhaas, A. König, J. S. Lee, R. Meys, S. Völker, M. Wessling, J. H. Lee and A. Mitsos, Early-stage evaluation of emerging CO2 utilization technologies at low technology readiness levels, Green Chem., 2020, 22, 3842–3859. 11 H. Yano, T. Tanaka, M. Nakayama and K. Ogura, Selective electrochemical reduction of CO2 to ethylene at a three-phase interface on copper(I) halide-confined Cu-mesh electrodes in acidic solutions of potassium halides, J. Electroanal. Chem., 2004, 565, 287–293. 12 J.-B. Vennekoetter, R. Sengpiel and M. Wessling, Beyond the catalyst: How electrode and reactor design determine the product spectrum during electrochemical CO2 reduction, Chem. Eng. J., 2019, 364, 89– 101. O-F14: Application of computer-aided tool (ArKaTAC³) for

assessment of Carbon Dioxide (CO2) Emissions Control Strategies: Evaluation of multi-path carbon capture and utilization (CCU) system for optimal solution. Hasan Imran*a, Ali S. Al Hunaidya, Yasmeen A. Dawsaria Hyungmuk Limb, Wonsuk Chungb, Jay H. Lee,b a Carbon Management Division, Research & Development Center, Saudi Aramco, Dhahran 31311, Kingdom of Saudi Arabia b Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea. * Corresponding author: [email protected]

Abstract: To control the Green House Gas (GHG) emissions (especially CO2) in the industrial sector, CO2 capture & utilization (CCU) technologies are being viewed as viable alternatives. Various combinations of CCU technologies can be applied to several CO2 sources for producing valuable products and fuels. Many of the CCU technologies are not desired in terms of CO2 reduction or economic benefits, because the CCU pathways require energy. A specialized computer-aided tool ArKaTAC³

(Aramco/KAIST-Tool for Analysis of CO2 capture & Conversion systems) has been developed by integrating Techno-Economic Analysis (TEA) and Life Cycle Analysis functions. This tool (software) analyzes and optimizes multisource, multi-product CCU technologies. The tool provides environmental and economic benefits by specifying the economic and life cycle assessment data, such as the price and carbon footprint of the raw material and products. The graphical user interface (GUI) presents the most optimized results based on a given objective function, and the user can make an informed decision on CO2 management strategy selection. This presentation will provide development and working methodology of the software and its various applications.

Keywords: Greenhouse gas emissions, Carbon capture and utilization, CO2 conversion, Techno-economic analysis, CO2 lifecycle assessment, ArKaTAC3

O-F15: Lifecycle Environmental Impacts and Techno-Economic Performance of a Novel CCU Process to Produce Propane and Propene Guillermo Garcia-Garcia1, Katy Armstrong1, Peter Styring1, Marta Cruz Fernandez2, Steven Woolass2 1UK Centre for Carbon Dioxide Utilisation, Chemical & Biological Engineering, Sir Robert Hadfield Building, The University of Sheffield, Sheffield S1 3JD, UK 2Tata Steel, Unit 2, Meadowhall Business Park, Carbrook Hall Road, Sheffield S9 2EQ, UK

Life-Cycle Assessment (LCA) and Techno-Economic Assessment (TEA) are useful methodologies to assess the environmental and techno-economic performance of processes, respectively. Here, we apply both LCA and TEA to study a novel process to produce propane and propene from captured carbon dioxide. Such proposed processes utilise gases from the refinery and steel industries. We first present the main steps of both methodologies, as well as discussing the main findings reported in previous studies. We then discuss the results obtained by LCA to quantify the environmental impacts associated with the production of several catalyst choices involved in the chemical reaction. Finally, we discuss the different scenarios in which the LCA and TEA is being used, which includes location options in the Netherlands and Turkey, as well as current baseline scenarios and projected scenarios based on carbon capture and utilisation.

O-F16: Towards Integrated LCA & TEA: Guiding Principles and Key Questions Stephen McCord1, Tim Langhorst2, Yuan Wang3, Lorenzo Cremonese4, Peter Styring1*

1UK Centre for Carbon Dioxide Utilisation, Chemical & Biological Engineering, Sir Robert Hadfield Building, The University of Sheffield, Sheffield S1 3JD, United Kingdom. 3 Energy and Process Systems Engineering, Tannenstrasse 3, 8092 Zurich ETH Zurich, Zurich, Switzerland 3Technische Universität Berlin, Institute of Chemistry, Str. des 17. Juni 124, 10623 Berlin, Germany 4IASS Institute for Advanced Sustainability Studies e.V., Berliner Str. 130, 14467 Potsdam, Germany

Publication trends in CCU impact assessment (e.g. LCA, TEA) show a growing interest in, and a convergence towards, integrated economic & environmental assessment. Such a development offers significant potential for developing a more detailed and nuanced assessment of performance, allowing for practitioners and other stakeholders to balance environmental impact reduction against financial constraints. However, this trend does not come without potential pitfalls, as highlighted in [1]. There is a clear need to development guiding principles for aligning and combining LCA and TEA. Building on its existing guidance [2], the CO2nsistent project intends to deliver such guiding provisions – addressing five key questions on integrating LCA and TEA: What do we mean by integration? Why should we integrate? When should we integrate? What should we integrate? How should we integrate? These questions combined with the existing guidance provisions feed directly into the development of new provisions specifically for integrated assessment. These new provisions cover aligning specific LCA and TEA studies, the development of combined indicators and the use of multi-criteria decision analysis within integrated assessment.

[1] J. Wunderlich, K. Armstrong, G. A. Buchner, P. Styring, and R. Schomäcker, “Integration of techno-economic and life cycle assessment: Defining and applying integration types for chemical technology development,” J. Clean. Prod., vol. 287, p. 125021, Mar. 2021, doi: 10.1016/j.jclepro.2020.125021. [2] A. W. Zimmermann et al., “Techno-Economic Assessment & Life Cycle Assessment Guidelines for CO2 Utilization (Version 1.1),” 2020.

O-F17: CO2 Utilisation Technologies in the Media

Results of an analysis of CCU technologies’ perception in media coverage and the potential influence on acceptance of these innovative technologies Dr. Barbara Olfe-Kräutlein

Research Group “CO2 Utilisation strategies and Society”, Institute for Advanced Sustainability Studies, Potsdam, Germany

For their successful implementation, innovations such as CO2 utilisation technologies need acceptance among stakeholders like policy makers, NGOs and decisionmakers in the industry and the general public. Opinions and attitudes of these stakeholder groups are influenced media coverage, amongst other factors. The influence of media on the perception of topics has been studied in media- and communication studies since the 1950s, describing effects such as agenda setting (describing that media determine what recipients think about, e.g. Shaw and Shannon, 1992), framing (describing the influence of the context that media put an issue in, e.g. Scheufele 1999) or the gatekeeper function of the media (describing that media have an influence on which information will reach the recipients at all, e.g. Shoemaker and Vos, 2009 ). Therefore, to shed a light on how the public perception of CCU technologies may build up and influence its acceptance, the research group “CO2 Utilisation Strategies and

Society” is undertaking a three year media observation, where media reports on CO2 utilization technologies are systematically collected and analyzed. The aim is to answer five leading questions: In which context are CO2 utilization technologies mentioned? Which technologies, which aspects are in the foreground? What is viewed rather positively, what rather negatively? Which actors have their say in the media? Are there changes over time? The proposed contribution to ICCDU 2021 will present first results of the media observation project and draw conclusions about media effects on the perception of CCU. The results of this analysis add new knowledge about acceptance of CCU technologies and provide supportive information for the communication efforts on CCU in science and industry. The media observation is part of the project CO2-WIN Connect, funded by the German Federal Ministry for Education and Research. Literature: Potter, W. James. Media effects. Sage Publications, 2012; Bryant, Jennings, and Dolf Zillmann. "Media effects." Advances in theory and research. New Jersey: LEA (2002); Shaw, Donald L., and Shannon E. Martin. "The function of mass media agenda setting." Journalism quarterly 69.4 (1992): 902-920., Dietram A. "Framing as a theory of media effects." Journal of communication 49.1 (1999): 103-122; Shoemaker, Pamela J., and Timothy Vos. Gatekeeping theory. Routledge, 2009. O-F18: Investigating the opportunities of coupling carbon capture and utilization with the supply chains of construction industry: a case study from western Germany

Ali Abdelshafy, Grit Walther Chair of Operations Management, RWTH Aachen, Aachen, Germany

Industrial process emissions are going to be the major obstacle to achieving carbon neutrality especially in the regions with insufficient geological storage capacities. Moreover, the legal complexities and social resistence restrain the policymakers from including carbon capture and storage (CCS) in their decarbonization strategies. Therefore, carbon capture and utilization (CCU) will be a convenient solution to sequester the process emissions where CCS is not applicable.

This paper present a case study from the German federal state of North Rheine – Westphalia to display the potentials of coupling CCU with the supply chains of construction industry by means of carbonating the cement products and construction and demolition waste. Based on extensive data mining and statistical analyses, the locations and outputs of the concrete and recycling plants have been determined. A techno-economic assessment has been implemented to quantify the sequestration capacity of the plants (carbon sinks) and calculate the transportaion costs. Simultenously, a location-allocation model has been applied to allocate the carbon sources (i.e. cement and lime plants) to the potential carbon sinks.

The analysis shows that the total squestration capacity is up to 1.8 Mt with an average transportation distance of 55.6 km (12.3 EUR/ton). Nonetheless, some emission sources have a clear comparative advantage in terms of their closeness to the carbon sinks as the distance ranges between 8.8 km and 142.3 km. Similarly, some carbon sinks have a comparative advantage in terms of their capacity and technology readyness level based on the product characteristics (e.g. RMC vs. precast and reinforced vs. non-reinforced products). Therefore, the paper also present models for the different products in order to display the potetentials of each category seperately and offer more flexibility to the producers and policymakers.

O-F19: Developing a Triple Helix Approach for CO2 Utilisation Sustainability Impact Assessment Katy Armstrong, Stephen McCord and Peter Styring UK Centre for Carbon Dioxide Utilisation, Department of Chemical & Biological Engineering, University of Sheffield, Sheffield, United Kingdom

To ensure sustainable CO2 utilisation (CDU) deployment, holistic assessment methodologies are a necessity which incorporate economic, social and environmental aspects. These concepts can be further considered as a triple helix structure with cross-linkages between parameters. In CDU, assessments to date have focused on the economic and environmental impacts and, though guidelines for Techno- Economic (TEA) and Life Cycle assessment (TEA) have been presented, a methodology for social impact assessment (SIA) of CDU has not. Typically, social impact is considered at a higher technology readiness levels (TRL) However, leaving such considerations solely to high TRLs could lead to inadvertent investment in socially unsustainable CDU. Therefore, the question is raised as to how SIA can be applied earlier? Additionally, does earlier application give meaningful assessment results? Furthermore, can the indirect impacts also be addressed such as using conflict minerals in catalyst synthesis or high renewable energy demand? By applying SIA to common CDU technologies (production of methanol, minerals and polymers); this research heuristically identifies key social indicators to create a framework that can be incorporated into a triple helix of “integrated” assessments. Assessment is conducted using a scoring framework, considering process, chemistry and scenario-specific factors. Both process and deployment scenarios are found to be key factors in the assessment and the sourcing of raw material is observed to be a hotspot for social impacts within the assessed CDU technologies. This triple helix approach will enable trade-offs between environmental, economic and social impacts to be explored, ultimately enhancing effective decision making for CDU development and deployment.

McCord, S., Armstrong, K., Styring, P., 2021. Developing a Triple Helix Approach for CO2 Utilisation Assessment. Faraday Discuss. https://doi.org/10.1039/d1fd00002k

Conference Abstracts

- Poster Session -

P-1: Performance of flat-tubular solid oxide co-electrolysis cells for syngas production by electrochemical conversion of H2O/CO2 T. H. Lim, D. W. Joh, H. S. Kim, J. E. Hong, S. B. Lee, S. J. Park, J. W. Shin, J. E. Kim, R. H. Song Fuel Cell Laboratory, KIER 152, Gajeong-ro, Yuseong-gu, Daejeon, 34129, Korea, *[email protected]

Using electricity from wind and solar sources, high-temperature solid oxide co- electrolysis cells (SOCs) can perform advantageous conversion of H2O/CO2 to high value syngas that can be used to produce electricity or synthetic hydrocarbons. In this work, the performance characteristics of flat-tubular solid oxide co-electrolysis cells are reported for production of syngas by electrochemical conversion of H2O/CO2. Anode-supported flat-tubular solid-oxide electrolysis cells were fabricated and tested at various operating temperatures and under various combinations of inlet-gas conditions. We also fabricated different electrolyte type SOC cells involving yttria- stabilized zirconia (YSZ) and scandium-stabilized ScSZ to improve the syngas yield. The electrochemical performance was analyzed using I-V curves, EIS analysis, and gas chromatography. Consequently, we confirm the correlation between the operating conditions and the electrochemical performance of the co-electrolysis process in the flat-tubular SOCs. Furthermore, it was found that the syngas yield of the ScSZ electrolyte-based SOC cell was better than that of the YSZ electrolyte-based SOC. The results show that using a flat-tubular SOC offered a high-efficiency conversion of H2O/CO2, with high yield and good-quality syngas.

P-2: Enhanced carbon dioxide hydrate formation via superabsorbent polymers (SAPs) and tetrahydrofuran (THF) Dong Woo Kang1, Wonhyeong Lee1, Yun-Ho Ahn2, and Jae W. Lee1,* 1Department of Chemical & Biomolecular Engineering, Korea Advanced Institute of Science and Technology 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea 2Department of Chemical Engineering, Soongsil University 369 Sangdo-ro, Dongjak-gu, Seoul 06978, Republic of Korea *[email protected]

Clathrate hydrates are ice-like compounds formed by 3-dimensional network of hydrogen bonding, which can trap small guest molecules such as hydrogen or methane inside their cavities. With this unique property, the hydrate has been widely studied for gas storage and separation. However, greenhouse gas capture by formation of carbon dioxide hydrate formation is still challenging, due to its low storage capacity despite of introducing surfactant such as SDS. Here, we combined tetrahydrofuran (THF) and superabsorbent polymers (SAPs) for improving carbon dioxide hydrate formation without mechanical agitation, which showed excellent performances for methane hydrate formation in a previous study.1 The storage capacity, induction time, and kinetics of hydrate formation were studied with respect to molar concentration of THF, and these results were compared with cases in the absence of SAPs. Also, scaled-up experiments were conducted for designing feasible hydrate-based carbon capture process. Finally, Raman and PXRD spectroscopic analyses were conducted to confirm whether ‘tuning phenomena’ occurred below the stoichiometric concentration of THF.

References [1] Kang, D. W.; Lee, W.; Ahn, Y.-H.; Lee, J. W., Confined tetrahydrofuran in a superabsorbent polymer for sustainable methane storage in clathrate hydrates. Chem. Eng. J., 2021, 411, 128512-128522.

P-3: Amine-impregnated metal organic frameworks-drived carbon (MDC) for carbon dioxide capture Seong Cheon Kim1, Cheolhyeon Jo1, Dasom Jeong1, Dae Hee Yun1, Jeasung Park1* 1Green and Sustainable Materials R&D Department, Korea Institute of Industrial Technology, Cheonan-si, Republic of Korea *[email protected]

Carbonaceous nanomaterials with uniform pore size have been widely used in gas adsorption. However, These carbon-based absorbent have physically weak interaction with carbon dioxide and leads to the limitation of CO2 adsorption. To improve CO2 absorptive capacity, this work introduced different metal organic frameworks(MOFs)- derived carbon (MDC) materials that have the homogeneous 3D structure, desirable pore size, and modular features. Additionally, different types of amine are used as physical impregnation into MDC to increase the adsorption capacity for CO2. MDC showed different CO2 adsorption tendency in comparison with primary MOFs and had different capacities according to pore size, BET, and their structures. As well,

Functionalized MDCs reported the increased CO2 adsorption capacities with different PEI (polyethylenimine) loading.

P-4: High Improvement in CO2 Chemisorption by Adding Co to

Li2ZrO3 L. J. Ortega-Rosas1, C. Cortés-Aguirre1, H. Martínez-Hernández2 and J. A. Mendoza-Nieto1* 1Departamento de Fisicoquímica, Facultad de Química, UNAM, Mexico city, México 2Departamento de Ingeniería en Metalurgia y Materiales, ESIQIE, IPN, Mexico city, México *[email protected]

Various alternatives have been proposed to reduce carbon dioxide (CO2) emissions, among them the use of alkaline ceramics for the capture of CO2, avoiding its emission to the atmosphere.1 To achieve this, a great variety of alkaline materials have been proposed, trying to make their synthesis as simple, economical, and feasible as possible. The first ceramic proposed in history to capture CO2 was lithium 2 zirconate (Li2ZrO3). It has been found that this ceramic does not achieve a CO2 capture of more than 1% by mass. Therefore, in this research work, the addition of cobalt in lithium zirconate is proposed, to achieve an increase in CO2 capture. Li2ZrO3 was synthesized by zirconium acetate (Zr(C2H4O2)4), lithium acetate (CH3O2Li*2H2O), and cobalt acetate (Co(C2H3O2)4*4H2O). All acetates were mixed, considering an excess of 15% for the lithium precursor, and different amounts of cobalt (Co) atoms: 10-50% wt. concerning zirconium atoms. Subsequently, mixtures were calcined at 400°C for 4h; then, at 900 °C for 6h. The structural and microstructural characterization of the lithium zirconate-based materials were characterized by XRD, FT-IR, and N2 physisorption. For CO2 capture tests, dynamic and isotherm analyses were realized, pure and doped Li2ZrO3 materials were evaluated between 30-900 ºC, with a ramp of 4ºC/min, and a saturated flow of 60 mL/min of CO2. The results showed that the chemical modification through the addition of low amounts of cobalt (<20% wt), the preservation of the starting material was obtained. However, as the amount of Co continued to increase, the presence of a secondary phase, lithium cobaltate, was detected. In CO2 capture between 400-600°C, the sample with the highest amount of Co (50% wt) had a maximum capture of 9.6%, equivalent to an increase of almost 10 times more compared to the pure material. Subsequently, between 650 and 900°C, a second capture process was observed, with an increase of up to 7%. It should be noted that this second stage was not observed in the pure material, so the secondary phase of lithium cobaltate must be responsible.

Acknowledgment This work was financed with the PAPIIT-UNAM IA-106321 grant. References [1] A. Yamasaki, J. Chem. Eng. Japan. 36 (2003) 361–375. [2] T. Nakagawa, K.; Ohashi. J. Electrochem. Soc. 145 (1998) 1344–1346. P-6: Multi-walled carbon nanotubes synthesized at the expense of carbon dioxide for the electrode of super-capacitor Gi Mihn Kim, Won-Gwang Lim, Dohyung Kang, Jae Hyun Park, H. Kim, Hyunjoo Lee, Jinwoo Lee, Sang Y. Lee, and Jae W. Lee* Chemical and Bio Enginnering Department, Korea Advanced Institute of Science and Technology (KAIST), Dae-jeon, Korea, Republic of *[email protected]

Ever-increasing emission of carbon dioxide (CO2) in an atmosphere has steadily brought out a colossal aftermath with respect to global warming throughout the overall anthropological history. With this problem in mind, a variety of CO2 capture and utilization methods have been considered. Above all, the conversion of CO2 into carbon material, especially for carbon nanotubes (CNT) is fascinating alternatives due to its high-valuable application for the energy storage. In this study, multi-walled CNT was successfully synthesized through the synergetic reaction of both sodium borohydride

(NaBH4) and nickel nanoparticles at the expense of CO2 under mild condition (~700

˚C, 1atm). NaBH4 is capable of entrapping the gaseous CO2 over 500 ˚C, while produced CO can be further reduced sequentially to CNT via electron-abundant surface of nickel as a catalyst. The resultant CNTs have plenty of boron and oxygen sites in the carbon framework, which endows its pseudo-capacitive property in an exceedingly positive way. Moreover, a meso-pore structure caused by the aperture between CNT fibers could expedite the process of ionic transport through electrolyte system composed of 1M TEABF4 in acetonitrile, which contributes to effective electrochemical performances. As a result, CNTs induced from CO2 secured high cyclic stability up to 10,000 times and delivered stable pseudo-capacitances above 300 F g-1 at 0.1 A g-1. At even high current density about 200 A g-1, this CNTs exceptionally shows 13 Wh kg-1 and 115 kW kg-1 of energy density and power density respectively.

P-7: Utilization of CO2 in Oxidative Dehydrogenation of Ethane over Bimetallic Catalysts Muhammad Numan,a Eunji Eom,a Changbum Joa Department of Chemistry and Chemical Engineering, Inha University, 100 Inha-ro, Michuhol-gu, Incheon, 22212, Republic of Korea

Ethane oxidative dehydrogenation using CO2 as soft oxidant for synthesis of ethylene is most attractive route. Pt based zeolite supported bimetallic catalysts were prepared using rare earth metal as second metal. Commercial silica supported PtCe bimetallic catalyst (PtCeO2@SiO2) was also prepared. These catalysts were examined for oxidative dehydrogenation of ethane to ethylene with CO2 being soft oxidant. The fresh catalysts were characterized using STEM, Extended X-ray absorption fine structure (EXAFS), ICP-OES, TGA and CO-Chemisorption. EXAFS results of zeolite supported PtCe (PtCe@MZ) catalyst had nanoparticles with ~ 2nm size. The PtCe@MZ catalyst gave stable activity with 39% conversion and 89% ethylene selectivity. The other catalysts were comparatively less stable. The comparison of fresh and spent catalysts characterization results revealed that Pt@MZ and PtCeO2@SiO2 catalysts suffered from coke deposition, which is possibly due to strong interaction of Pt with ethylene, lead in deep dehydrogenation that resulted in coke formation. This coke deposition was almost negligible for PtCe@MZ catalyst.

P-8: Hierarchical porous carbon derived from CO2 and N-doped electro-spun interlayer for inhibiting the shuttle phenomenon in Lithium Sulfur batteries Jae Hyun Park, Hyeonseo Gim, Won Yeong Choi, Heecheon Lee, Sang Yeon Lee, and Jae W. Lee Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea

Shuttle effects resulted from lithium polysulfides (LiPSs) become inevitably deeper as charging/discharging process proceeds in lithium-sulfur (Li-S) batteries. Derived from natural solubility of LiPSs into organic electrolyte, the phenomena lowers the Coulombic efficiency in every cycle, eventually causing the irreversible loss of active materials. To suppress the shuttle phenomena and bring out the potential capacity, hierarchical porous carbon derived from CO2 and electro-spinning carbon nanofiber is co-introduced as the cathode and an interlayer respectively in this work. The hierarchical pore structure, especially centered on meso-area could accommodate enough sulfur and be equally dispersed onto the carbon surface, enabling each sulfur particle become effectively conductive. Also, composed of the abundant nitrogen-site about 15at. %, this interlayer would entrap the LiPSs mostly through the mechanism of chemical adsorption, as well as the role of physical barrier simultaneously. The sluggish redox reaction caused by insulating property of sulfur was able to be overcome through the aspect of well-precipitated Li2S and Li2S2 on the interlayer, thereby keeping interfacial contact electrochemically conducive. As a result, the cell assembled can deliver about 700 mAh g-1 within 500th cycle at 0.5 C and even 7 C- rate of charging/discharging environment, it still shows near 700 mAh g-1 at the first cycle.

P-9: Incorporation effect of Ca on Ni-exsolved LaNiO3 perovskite catalyst for promoting CO2 methanation Hyun Suk Lim, Gunjoo Kim, Yikyeom Kim, Minbeom Lee, Dohyung Kang, Hyunjoo Lee, and Jae W. Lee 1Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) [email protected]

This work studies the enhancing effect of Ca on CO2 methanation reaction on the Ni- exsolved La1-xCaxNiO3 (0 ≤ x ≤ 0.6) perovskite-based catalysts. HAADF-STEM images presented that the metallic Ni particles are exsolved on the surface of perovskite under a reducing atmosphere, where this exsolution tendency is observed until the Ca ratio (x) becomes 0.4. This suggests that excess incorporation of Ca rather prevents the dispersion of Ni particles, which may eventually hinder the adsorption and dissociation of H2 molecules. In-situ DRIFTS reveal that the Ca-sites on the surface can effectively adsorb CO2 molecules to form reactive carbonates species. XPS analyses and CO methanation tests further show that adding Ca negatively charges the adsorption sites of CO2 molecule, thereby promoting the activation of CO molecule. This surface coordination is optimized by incorporating 0.4 of Ca, presenting the facile hydrogenation of CO molecules to CH4. Thus, incorporating 0.4 of Ca into the A-site of LaNiO3 demonstrated the optimized promoting effect on CO2 methanation.

Acknowledgements The authors acknowledge financial support from the KCRC Program and the UK- Republic of Korea Joint Research Program (NRF-2014M1A8A1049297 & NRF- 2019M2A7A1001773) funded by the Ministry of Science and ICT.

Reference [1] Chemical Engineering Journal. 2021, 412, 127557.

P-10: CO2-derived free-standing carbon electrode with high performance in lithium-sulfur battery. J. Yang, J. H. Park, W. Y. Choi, D. Kim, H. Gim, and Jae W. Lee Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea E-mail: [email protected]

The research on synthesizing free-standing electrodes is emerging as a method to increase the ratio of active materials in lithium-sulfur (Li-S) batteries. This study succeeded in synthesizing a free-standing electrode with high porosity and superior flexibility through CO2 conversion process. The CO2-derived electrode synthesized in this study can fully utilize the characteristics of the free-standing electrode, ensuring very high areal loading without electrode collapse or cracking. Electrospinning method mixed with polyacrylonitrile (PAN) is used for the fabrication of electrode before CO2 conversion, which allows about 20 wt% of nitrogen (N) atoms to present on the surface of the synthesized electrode. Excess N on the surface inhibits the diffusion of the polar intermediates toward the opposite Li electrode caused by the shuttle phenomenon through strong chemical interaction, which significantly reduces the irreversible capacity degradation. Additionally, N atoms improves the conductivity of the material to exhibit superior specific capacity even at high current density. As a result, the free- standing electrode with about 2.54 mg cm−2 sulfur loading delivered about 650 mAh −1 g specific capacity at 5.0 C. Based on its outstanding porous properties, CO2-derived free-standing electrode was possible to impregnate with a high areal loading of 6.11 mg cm−2 and delivering an areal capacity of about 3.1 mAh cm−2 at 500th.

P-11: Enhancement of the reactivity for low-temperature CO2 splitting by using a metal oxide-perovskite composite oxygen carrier Minbeom Leea, Yikyeom Kima, Hyun Suk Lima, Ayeong Joa, Dohyung Kangb*, and Jae W. Leea* a Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-Ro, Daejeon 34141, Republic of Korea b School of Chemical Engineering, Yeungnam University, 280 Daehak-Ro, Gyeongsan 38541, Republic of Korea [email protected], [email protected]

Atmospheric CO2 concentrations have steadily increased for the recent few decades.

Among the CO2 conversion methods, reverse water-gas shift chemical looping

(RWGS-CL) is the process with two-step redox cycle, which are the H2 reduction step and CO2 oxidation step. It can be a powerful process because of the high conversion rate of CO2 to CO at the low operating temperature. Furthermore, it can produce CO without additional separation process because the reduction and oxidation steps are conducted in the separated spaces. This paper introduces perovskite and metal oxide- perovskite composite oxygen carriers for the RWGS-CL process. Synthesized oxygen carriers were analyzed by the ICP-MS, XPS, and HAADF-STEM measurements. RWGS-CL results proved that the metal oxide-perovskite composite oxygen carriers showed higher CO2 conversion rate and CO yield than the single perovskite oxygen carrier. Among the tested oxygen carriers, which were La0.75Sr0.25FeO3 (LSF),

CeO2@LSF, NiO@LSF, Co3O4@LSF, and Co3O4-NiO@LSF, LSF-encapsulated

Co3O4-NiO was the most promising oxygen carrier, because it showed the highest CO yield and cyclic stability.

P-12: Effect of Cu on the carbonization of Fe species over Fe-Cu

bimetallic catalyst in CO2 hydrogenation Miao Zhang1, Guanghui Zhang1, Mingrui Wang1, Xinwen Guo1,*, Chunshan Song1,2,* 1State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024 2Department of Chemistry, The Chinese University of Hong Kong, Shatin, Hong Kong E-mail: [email protected]; [email protected]

It is of great significance to understand the role of each component and the interaction in bimetallic catalyst design. According to the literature, Fe-Cu bimetallic catalyst has a strong synergistic effect in CO2 hydrogenation, thus promoting the formation of C2+ hydrocarbons. In our work, we chose well-defined CuFe2O4 as a precursor to explore the role of Cu in Fe-Cu bimetallic catalyst for CO2 hydrogenation. From the in situ X-ray diffraction and in situ DRIFTS results, one can see that Cu is conducive to the reduction and further carbonization of Fe species. Moreover, we confirmed that the undesired oxidation of metallic Fe is apparently suppressed due to the introduction of Cu.

Fig.1 In situ XRD patterns of CuFe2O4 during prereduction and CO2 hydrogenation

References [1] Wang, W.; Jiang, X.; Wang, X.; Song, C. Industrial & Engineering Chemistry Research. 2018, 57, 4535 [2] Nie, X.; Wang, H.; Janik, M. J.; Chen, Y.; Guo, X.; Song, C. The Journal of Physical Chemistry C. 2017, 121, 13164

P-13: Selectivity Control with Surface Ligand on Cu2O/TiO2 Photocatalyts for Gas-Phase Carbon Dioxide Reduction Gui-Min Kim, Sunil Jeong and Doh C. Lee* Department of Chemical and Biomolecular Engineering, KAIST Institute for the Nanocentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea

We report CO/CH4 selectivity control on photocatalytic gas-phase CO2 reduction with

H2O. The key strategy for selectivity modulation is surface ligand passivation with taurine and ethylenediamine on Cu2O/TiO2 photocatalyst. By passivating taurine on

Cu2O/TiO2, the selectivity of CH4 increases. When ethylenediamine is absorbed, CO selectivity increases significantly. In situ Fourier transform infrared spectroscopy and density functional theory calculation reveal that the surface ligands on the photocatalyst surface alter the binding strength of reaction intermediates.

P-14: Solar-Driven Conversion of CO2-to-CO with All inorganic CdS Nanosheets Nianfang Wang and Doh C. Lee* Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea Solar-driven carbon dioxide (CO2) photo-reduction into chemical fuels provides a sustainable way to produce renewable energy sources by consuming the ever- increasing greenhouse gas. Nevertheless, due to intrinsic inertness (~750 kJ mol-1 of C=O bond dissociation energy) of linear CO2 molecule, a high photon energy input or multiple proton coupled electron transfer process is generally required to activate CO2 molecule, which leads to considerable thermodynamic and kinetic barriers that limit the overall photo-conversion efficiency and selectivity of CO2 photo-reduction. In addition to thermodynamic and kinetic barriers of CO2 photo-reduction, the other two basic steps of CO2 photo-reduction, light absorption and charge separation, should never be ignored. Notably, these two parameters are very tricky to control because of the inherent conflicts associated with photo-physical process, the fate of the charge carriers and surface active sites. On one hand, extension of photo-absorption range inevitably sacrifice the redox potential of the charge carriers. On the other hand, the intrinsic imbalanced mobility of hole (h+) and electron (e-) coupled with mismatch between the desired migration of e- (and h+) and randomly distributed reduction reaction sites (and oxidation reaction sites) would increase the chance for e--h+ recombination and photo-corrosion, thus, hindering the photo-conversion efficiency and the long-term stability of the photo-catalyst. Therefore, CO2 photo-reduction is widely regarded as a thorny subject in photo-catalysis. Here, in an attempt to establish a universal guideline for rational design of stable photo-catalyst with high photo- conversion efficiency and selectivity for CO2 conversion. We systematically investigate the structure-photocatalytic properties correlations using binary CdS colloidal nanocrystal (NC) as a model system. The colloidal CdS nanocrystal is chosen not only for the tunable band structure (≥2.41 eV) which can potentially afford visible light harvesting and sufficient energetic e- and h+, but also for the versatile controllability over its morphology, crystal structure and surface termination, which provides a broad monitoring window enable us to clarify the structure-property relationship in complex CO2 photo-reduction process. P-15: Quantum Dot-Mediated Photodynamic Therapy for Multidrug- Resistant Bacteria Inactivation Ilsong Lee, Doh C. Lee* Department of Chemical and Biomolecular Engineereing, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea

Multidrug-resistant (MDR) bacteria infection is a serious problem in many countries. Antimicrobial agetns with high antibacterial efficiency and biocompatibility are desirable. Reactive oxygen species (ROS), which is toxic to bacterial cells, is one of reactive species responsible for the photoactivity of semiconductor nanoparticles. Herein, we have prepared highly efficient bactericidal colloidal nanocrystal quantum dots (QDs). The bandgap energy of cadmium-free QDs (indium phosphide quantum dots, InP QDs) was tuned their size. The cadmium-free QDs were treated to gram- positive (MDR Bacillus cereus and Staphylococcus aureus) and gram-negative (MDR Pseudomonas aeruginosa and Escherichia coli) bacteria and the bacterial viability was analyzed to confirm the QD-induced bacterial cell death. The cadmium-free QDs efficiently attacked and inhibited the bacterial cells, but had less effect on the mammalian cells (HeCaT, COS-7 and dermal). Animal exmeriments further showed that the cadmium-free QDs can effectively treated wounds infected with MDR Staphylococcus aureus. The cadmium-free QDs could be used for clinical photodynamic therapy to care the bacterial infections.

P-16: Ultrasmall Synergistic Nanocluster Catalyst for CO2 Conversion Jiasheng Wang, Haohua Jin, Wan-Hui Wang, Ming Bao School of Chemical Engineering, Dalian University of Technology, Panjin, China

CO2 is a greenhouse gas which has contributed to suitable temperature and survival of all creatures on earth. However, with the acceleration of industrialization, its concentration in the atmosphere is increasing, leading to a series of serious problems, such as global warming, glacial melting, and sea level rising. Conversion of CO2 into fuels and chemicals has been considered to be an important strategy to reduce greenhouse gas emissions and alleviate the energy crisis.

Bicarbonate as the CO2 source is convenient for experimental operation. The use of inexpensive metals as catalysts has become the direction of research. Here we designed a series of ultrasmall Ni-ZnO catalysts with size between 1.5 and 3 nm loaded on a silica support whose size ranges from 26 to 95 nm[1,2]. The optimum size of the active component is about 2 nm, just at the threshold size of the nanocluster due to a suitable ratio of low- and high-coordinated surface atoms. Besides, the synergistic effect between Ni and ZnO significantly enhances the activity of Ni. We studied the activity of catalyst in hydrogenation of bicarbonates and explored the possible mechanism of catalyst action. The yield of formic acid reached up to 97.0% at 260 °C/3 MPa for 2 h, which is higher than those of the ever reported non-noble metal-based catalysts, reaching the effect of the precious metal catalyst.

The good performance of the Ni-ZnO/SiO2 can be attributed to the ultrasmall active component size and the synergy effect based on electron transfer between Ni and ZnO.

References 1. ACS Appl. Mater. Interfaces 2020, 12, 17, 19581–19586. 2. Catal. Commun. 2020, 141, 106013.

P-17: Electrospun Carbon Nanofibers: A CO2 Selective Adsorbent for Carbon Capture V. Selmert,1,2 A. Kretzschmar,1,2 H. Weinrich,1 H. Tempel,1 H. Kungl,1 R.-A. Eichel1,2 1IEK-9, Forschungszentrum Jülich GmbH, Jülich, Germany 2IPC, RWTH Aachen, Aachen, Germany

To limit the amount of emitted CO2 and mitigate its effect on the global warming, efficient separation technologies for the capture of CO2 are necessary. Among others, adsorption-based processes such as pressure swing adsorption (PSA) and vacuum swing adsorption (VSA) are currently considered as promising methods for the capture of CO2 from CO2-rich sources. As such gases often contain N2 as main component like for example flue gas, the selective adsorption of CO2 over N2 is a critical feature of the adsorbent used in these processes. In addition, the adsorbent determines further important aspects like the CO2 capacity, the adsorption kinetics, or the long-term stability making the adsorbent a key component. In our work, polyacrylonitrile (PAN)-based carbon nanofibers (CNFs) were investigated for their application as CO2 selective adsorbent. The CNFs were prepared by electrospinning followed by stabilization in air at 250 °C and subsequent carbonization at various temperatures ranging from 600 °C to 1000 °C. For the analysis of the gas separation capabilities, mixed gas adsorption experiments were performed with CO2 and N2 under conditions close to PSA or VSA processes using the dynamic gas adsorption technique. Our investigations show that the CNFs carbonized at 800 °C or below feature an excellent CO2/N2 selectivity of 27 to 29 (25 °C, 1 bar, 5% CO2 in N2) compared to other carbon materials. Furthermore, the selectivity increases with lower CO2 fraction, overall pressure or measurement temperature reaching values up to 117. The analysis of the shape of the breakthrough curves reveals kinetic limitations on CNFs carbonized at 800 °C and 900 °C, but fast adsorption kinetics on CNFs carbonized at 600 °C and 700 °C. Finally, long-term measurements demonstrate a high stability of the CNFs with no observed change in the adsorption capacity over the tested range of 300 ad- and desorption cycles. The combination of these excellent properties and their cheap and scalable synthesis procedure make PAN-based CNFs carbonized at 600 °C or 700 °C a promising adsorbent for the capture of CO2. P-18: Transformation of CO2 to Propiolic Acids with Ammonium Salts via Dual Activation

Wan-Hui Wang, 1,2) Xiujuan Feng 1) and Ming Bao 1,2) 1) State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, 116023, China 2) School of Chemical Engineering, Dalian University of Technology, Panjin, 124221, China

Emission of huge amount of greenhouse gas CO2 leads to global warming and serious environmental problems. Transformation of CO2 to fine chemicals has 1 attracted increasing attention since it contributes to CO2 elimination. Propiolic acids are widely used as important intermediates in organic synthesis and medicinal chemistry. Herein, we introduce our recent research on CO2 transformation to propiolic acid (Figure 1).2,3 A new strategy using quaternary ammonium salt via dual activation in the presence or absence of copper salt was developed for carboxylation of terminal alkyne with CO2 under mild conditions in a favorable solvent MeCN. This strategy was capable to produce various substituted propiolic acids in high to excellent yields.

References 1. Qiao, C.; Cao, Y.; He, L.-N.; Mini-Rev. Org. Chem. 2018, 15, 283. 2. Wang, W.-H.; Jia, L.; Feng, X.;* Fang, D.; Guo, H.; Bao, M.;* Asian J. Org. Chem. 2019, 8, 1501.

3. Wang, W.-H.; Feng, X.; Sui, K.; Fang, D.; Bao, M.* J. CO₂ Util. 2019, 32, 140.

P-19: Effect of hygroscopicity of ethanolamine based solutions on

CO2 absorption-desorption performance and its refinement Yiming Zhao, † Shaoyun Chen, *,†,‡ Yongchun Zhang*,†

† A State Key Laboratory of Fine Chemistry, School of Chemical Engineering, Dalian

University of Technology, Dalian 116024, China.

‡ Luoyang Research Institute of Dalian University of Technology

The presence of water vapour in industrial waste gases has an important influence on the study of CO2 capture performance of non-aqueous solutions due to the strong hygroscopicity of amine solutions. The effect of water content in the solution on the

CO2 capture performance of non-aqueous solutions was investigated using an absorption-desorption apparatus. The results confirmed that an increase in the water content of the solution significantly affected the regeneration performance of the solution. The effect of hygroscopicity was controlled by the addition of piperazine (PZ) aqueous solution, resulting in a regeneration efficiency of over 94.2%. The reaction 13 mechanism of EMEA+DEEA+PZ aqueous solution+CO2 was investigated by C NMR spectroscopy, and the results showed that PZ was involved in the chemical uptake of

CO2, which improved the regeneration efficiency of CO2 in aqueous solution, thus weakening the effect of water content in non-aqueous amine solutions.

P-20: The surface modification of CdS photocatalyst by inorganic ions for the improvement of CO2 reduction Pan Lu, Doh Chang Lee * Department of Chemical and Biomolecular Engineering, KAIST Institute for the Nanocentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea

Carbon dioxide (CO2) conversion has been attracted many concerns due to the high greenhouse gas level in the atmosphere. The photocatalytic reduction of CO2 is an attractive technology that uses directly solar energy to convert CO2 into valuable chemicals in an environment-friendly way. However, the effective reduction process is not easy because the cathodic process has a high overpotential barrier with low selectivity to a certain product. Recent research focused on the utility of co-catalyst to improve photocatalytic performance, while the effect of inorganic surface ligand remained largely unexplored. To the best of our knowledge, the only example where the inorganic ligands were used for photocatalytic CO2 reduction is the use of - Tetrafluoroborate (BF4 ) for the enhancement of yield. In this study, the effect of the capping anion ligands on photocatalysis will be studied.

P-21: Preparation of High-Purity H3Co(CN)6 for CO2/Epoxide Copolymerization Yeong Hyun Seo, Yong Bin Hyun, Bun Yeoul Lee* Department of Molecular Science and Technology, Ajou University, Suwon 16499, South Korea

Double metal cyanide (DMC) catalysts exhibit a very high efficiency for propylene oxide

(PO) and have been actively investigated for CO2/PO copolymerizations, which is one of the most attractive topic in the field of carbon dioxide capture and utilization. DMC catalysts are heterogeneous coordinative catalyst prepared by mixing K3Co(CN)6 and

ZnCl2 in water in the presence of some ligands (e.g., tBuOH) and whose structure is still elusive. The catalytic performance of DMCs is very sensitive to the preparation method, especially to the washing conditions, even influenced by mixing method. With aims not only to detour the cumbersome filtration procedure but also to ensure reliability as well as reproducibility, it was attempted to use H3Co(CN)6 instead of

K3Co(CN)6 in DMC preparation. In this work, we demonstrate a facile and large scale preparation of high-purity H3Co(CN)6 (100 g-scale), which was combined with 2.0 eq

ZnCl2 in methanol to precipitate solids which are highly active for CO2/propylene oxide copolymerization.

P-22: Syngas and Ethylene Production from Carbon dioxide and Methane via Solid Oxide Electrochemical Cell Minseok Bae1), Taehong Kim1), Kunho Lee3), Jun Hyuk Kim2), Joongmyeon Bae1), WooChul Jung2), Sai P. Katikaneni3) 1) Department of Mechanical Engineering, KAIST, Daejeon, Republic of Korea 2) Department of Materials Science and Engineering, KAIST, Daejeon, Republic of Korea 3) Carbon management R&DC, Saudi Aramco, Dhahran, Saudi Arabia

A new climate agreement was adopted at the 2015 Paris Climate Conference, COP 21. Countries worldwide have realized how serious climate change is and have submitted their pledges to the UN. Particularly, reducing CO2, the most critical greenhouse gas, is one of the significant challenges. To date, various approaches have been actively attempted to deal with the catastrophic CO2. Among those approaches, the utilization of CO2 in the way of electrochemical/electrolysis process has been gaining much attention since it allows to deal with the problem more productively and efficiently and has a high potential to utilize renewable energy. In this regard, we report a novel solid oxide cell (SOC), which enables to produce syngas

(CO+H2) and synthesize ethylene at the same time using CO2 and CH4. In this study, the novel SOC was fabricated, and the feasibility test of the fabricated novel SOC was carried out. The properties of the electrochemical cell and gas compositions are analyzed to find the possibility of utilizing CO2 via the electrochemical process.

P-23: Transfer Hydrogenation of CO2 using Iridium Complexes Bearing tris-N-Heterocyclic Carbene Ligands Yeon-Joo Cheong a and Hye-Young Jang a,* a Department of Energy Systems Research, Ajou University, Suwon 16499, Korea

Transition-metal-catalyzed transfer hydrogenation (TH) of carbon dioxide (CO2) is an attractive strategy for CO2 utilization. TH is a method of transferring hydrogen atoms from H-donor to H-acceptor without explosive hydrogen gas. Ketones, aldehydes, imine, and nitriles have been used as acceptors, and alcohols such as methanol, ethanol, and isopropanol have been commonly used as donors. In this presentation, we used glycerol as a sustainable hydrogen source. Glycerol, a by- product of biodiesel that can be used as a renewable energy source, is mainly used as a sustainable hydrogen donor. Formate obtained through TH of CO2 also a valuable chemical for hydrogen gas storage. However, due to the low reactivity of

CO2, the chemical conversion of CO2 is challenging. Therefore, the design of the catalysts is essential to promote the reaction. Various transition metal complexes for

TH of CO2 with glycerol are reported; Choudhury’s iridium catalyst with monodentate N-heterocyclic carbene(NHC) ligand and Voutchkova-Kostal’s water-soluble iridium and ruthenium catalysts. Herein, we have developed thermally stable mono- and bi- metallic iridium complexes involving modified NHC ligands showing high catalytic activity in the transfer hydrogenation of CO2. The detailed results will be discussed in this presentation.

P-24: Hydrogenation of CO2 into formate by phosphine-stabilized Pd/TiO2 catalysts M. Dolores Fernández-Martínez, C. Godard Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Campus Sescelades, c/Marcel·lí Domingo s/n, 43007, Tarragona, Spain In recent years, interest has grown both in reducing the emissions of CO2 from industry, and use CO2 as a source of C1 for the synthesis of high added value compounds.1 Compared to classical synthetic methods, direct CO2 hydrogenation for the production of formic acid/formate is important for two reasons: the valorisation of CO2 and its potential utilization as hydrogen storage.2 In this work, the preparation of heterogeneous catalysts based on palladium naoparticles supported on TiO2 is presented. These Pd NPs were synthesised through an organometallic approach in the presence of phosphines as stabilizing agents to fine tune their properties and performance in catalysis.3 Indeed, the aim was to modify the surface of these catalysts both at a morphological / size level and at an electronic level through their interaction with the stabilizer and the support. The catalysts were characterised by several techniques and their catalytic activity evaluated in the direct hydrogenation of CO2 into formate under batch conditions.

Scheme 1: Catalitic performance at Palladium stabilized and supported nanoparticles for carbon dioxide conversion to formate

References 1 Álvarez, A.; Bansode, A.; Urakawa, A.; Bavykina, A. V.; Wezendonk, T. A.; Makkee, M.; Gascon, J.; Kapteijin, F. Chem. Rev. 2017, 117, 9804−9838. 2 Ohi, J. J. Mater. Res. 2005, 20, 3180−3187; Zhong, H.; Iguchi, M.; Chatterjee, M.; Ishizaka, T.; Kitta, M.; Xu, Q; Kawanami, H. ACS Catal. 2018, 8, 5355−5362; Lee, J. H.; Ryu, J.; Kim, J. Y.; Nam, S.-W.; Han, J. H.; Lim, T.-H.; Gautam, S.; Chae, K. H.; Yoon, C. W. J. Mater. Chem. A, 2014, 2, 9490–9495; Kuwahara, Y.; Fujie, Y.; ihogi, T.; Yamashita, H. ACS Catal. 2020, 10, 6356–6366. 3 Philippot, K.; Chaudret, B. C. R. Chim. 2003, 6, 1019−1034. P-25: Designing Alkaline Earth Metal Incorporated Glass

Adsorbents for Capturing CO2 under Mild Conditions

Hyung-Ju Kim*, Sung-Jun Kim, Hee-Chul Yang, Hee-Chul Eun, Keun-Young Lee, Bum-Kyung Seo Korea Atomic Energy Research Institute, 989-111 Daedeok-daero, Yuseong-gu, Daejeon, 305-353, Republic of Korea

The synthesis of alkaline earth metal-incorporated glass adsorbents is described, and their CO2 capture properties are investigated under mild conditions to elucidate the heterogeneous nucleation mechanisms observed in these adsorbents. Alkaline earth metals are incorporated into the amorphous glass framework to capture acid gas by the carbonation reaction. The effects of heterogeneous nucleation are investigated by the physicochemical characterization and the CO2 capture mechanism in aqueous media. The alkaline earth metal-incorporated glass adsorbents show the high CO2 capacity, reaction rate, and efficiency of alkaline earth metal during operation even under room temperature. Further structure transformation from amorphous to crystalline reveals that crystallized alkaline earth metal-incorporated glass could capture CO2 with better performance due to the collective leaching of alkaline earth metal from the crystallized structure. This first study of alkaline earth metal-incorporated glass adsorbents indicates that they can capture CO2 with significant performance under mild conditions.

P-26: Solar Energy-Driven Upcycling of Polystyrene Model by Inducing Hydrogen Atom Abstraction Minsoo Kim, Doh C. Lee* Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea

Plastic is extensively used for numerous fields with high productivity and stability, but its recycling ratio is known to be about 14% and most of them are incinerated or landfilled. These make enormous damage to human beings, such as environmental and economic problems. In this study, the carbon-carbon (C-C) bond decoupling reaction of the plastic model molecule (1,3-Diphenylpropane) is demonstrated to solve this problem. Specifically, hydrogen atom abstraction is driven by several methods, which is known as the rate-determining step of the C-C decoupling reaction. Phenylbis(2,4,6-trimethyl benzoyl)phosphine oxide (BAPO), Cerium chloride (CeCl3), Cadmium sulfide quantum dots (CdS QDs) were used for efficient hydrogen atom abstraction and their performances are compared. As a result, CdS QDs showed the highest performance as photocatalysts and the reason is their unique characteristics such as high dispersity and large extinction coefficients.

P-27: Opportunities for long-term net-zero carbon emissions in the

cement sector by CO2 recycling Marta Rumayor, Javier Fernandez-Gonzalez, Maria Gonzalez-Marcos, Antonio Dominguez-Ramos, Angel Irabien Department of Chemical and Biomolecular Engineering, University of Cantabria, Santander, Spain

The decarbonization roadmap for cement industry has set four strategies to achieve net-carbon emissions by 2050 include improving energy efficiency, switching to low- carbon fuels, reducing the clinker to cement ratio, and implementing innovative carbon capture and utilization/sequestration (CCU&S) technologies. CCU&S cumulative emission savings accounts for 48% by 2050 in the 2-degree scenario (2DS) while fuel switching, expected to be deployed at nearer term, could represent a 42% reduction by 2050 comparing with the current CO2 emissions of the global cement production

[1]. Among them, CCU&S can curb most of the direct CO2 emissions from the process whereas fuel switching will reduce indirect CO2 emission associated with the fossil resources. In this study, we evaluate the environmental feasibility to achieve a net-zero implementation of a CO2 recycling plant (CO2RP), which is based on the emerging electrochemical reduction of CO2. An ex-ante life cycle analysis (LCA) will be used to evaluate the impact of the CO2RP on the cement carbon footprint (CF) [2]. The substitution of heat through power-to-heat (PtH), as well as the influence of hydrogen- powered cement, will be also analyzed. The best performance scenarios were explored yielding a full picture of the technology’s feasibility in this hard-to-abate sector and providing a perspective and the implementation challenges that should be addressed over the course of the next two decades.

Acknowlegments Javier Fernández-González and Marta Rumayor would like to thank the Spanish Ministry of Science, Innovation and Universities for financial support through FPU grant (19/05483) and Juan de la Cierva postdoctoral contract (IJCI-2017-32621), respectively. References [1] International Energy Agency (IEA) The challenge of reaching zero emissions in heavy industry, (2020). [2] Rumayor, M., et., 2020. Toward the Decarbonization of Hard-To-Abate Sectors: A Case Study of the Soda Ash Production. ACS Sustainable Chemistry and Engineering 8, 11956–11966.

P-28: Biodegradable low molecular weight poly(propylene carbonate) synthesized

by CO2/PO copolymerization from Castor oil Woo Yeon Cho, Hyun Woo Lee, Yeong Hyun Seo, Pyung Cheon Lee, Bun Yeoul Lee Department of Molecular Science and Technology, Ajou University, Suwon 16499, South Korea

Castor oil is one of widely used renewable feedstocks, and is used as a chemical component in industrial products including lubricants, coatings, inks and paints. Castor oil has inherent double bonds and secondary hydroxyl groups (-OH), which enable it to be functionally modifed. In our previous study, we developed cobalt(III)-Salen catalyst with excellent performance even in the presence of a large amount of a protic compounds. In this work, we synthesized various low molecular weight (MW) poly(propylene carbonate) (PPC) by chemically modifying hydroxyl groups of castor oil. Low MW PPCs of 9900 to 2700 g/mol were synthesized, and chemical/phyical properities of low MW PPCs, including biodegradability, was investigated. Lowering

MWs decreased the glass transition temperature (Tg) of PPCs from 20 ℃ to -33 ℃.

Biodegradability of PPCs in soils tended to be dependent on MWs and Tg. Information on functional properites of the low MW PPCs can serve as a basis for the development of new-type biodegradable PPCs with high applicability.

P-30: Synthesis of adsorbents for capturing CO2 from coal fly ashes: effect of the chemical and mineralogical composition of fly ashes dr Aleksandra Ściubidło, prof. Izabela Majchrzak-Kucęba Department of Advanced Energy Technologies, Faculty of Infrastructure and Environmental, Czestochowa University of Technology, Częstochowa, Poland

CO2 is believed to be the main cause of the greenhouse effect, and a large part of the increase in CO2 in the atmosphere is from the burning of fossil fuels. Carbon capture, utilisation and storage (CCUS) from flue gases has been considered as a key measure to reduce this effect in the short term. Therefore, the development of cost-effective techniques for the utilization of CO2 is considered to be one of the highest priorities in CCUS. The greatest emphasis is put on CO2 removal from flue gas using two methods: the absorption method, and adsorption on solid sorbents. The development of suitable low-cost, regenerable adsorbents with long lifetime is one of the major challenges of the capture of CO2. The sorbents should provide high adsorption capacities, fast adsorption rates and desirable desorption properties and easy regeneration. Due to the chemical composition -high content of SiO2 and Al2O3 - fly ash is an attractive material for the synthesis of sorbents. The article presents the synthesis of sorbent (MCM-41) from different type of fly ashes for capturing CO2. Fly ashes used for the synthesis process originated from the combustion of hard coal, lignite, from both fluidized-bed and pulverized-fuel boilers.

P-31: CO2 to food: solve the global challenges of greenhouse gas carbon dioxide and food shortage by converting CO2 to single cell proteins in gas fermentations Reza Ranjber* CPI [email protected]

Two challenges faced by the mankind are the overuse of fossil fuels and the subsequent overproduction of carbon dioxide as a greenhouse gas, and the shortage of proteins due to rising world population and growing need for protein rich diet. CPI aims to solve those challenges by research and developing technologies that converts CO2 to protein through gas fermentation. A class of microorganisms called chemolithotrophs which grow efficiently using CO2 as the sole carbon source and produce single cell proteins that is a good source of nutrition. CPI has developed the capability and owns the industrial know-how on gas fermentation at both the early stage R&D and later stage process development and piloting. It boasts a newly renovated gas fermentation lab consisting of lab scale fermenters specialising in gas fermentations using C1 gases, with which we helped customers to develop, prototype and demonstrate gas fermentation product/processes, moving fast from proof-of- concept to full production and commercialisation with speed and safety. This enables commercial services in the areas of high throughput host cell screening/selection, process characterisation and development, process modelling, techno-economic analysis, and piloting and process demonstration. A success story told is CPI has helped a customer built, commissioned and been operating a pilot scale purpose-built gas fermentation loop reactor to grow a Methylotroph using another C1 gas methane for the production of single cell proteins.

P-32: Molecular Ruthenium Cluster encapsulated ZIF-11 and Its

Carbon Derivatives for Conversion of Glycerol and CO2 Kyung-Ryul OH, Anil H. Valekar, and Young Kyu Hwang Research Center for Nanocatalysts, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea

The development of stable and high-performance heterogeneous catalyst is required to obtain value-added lactate (LA) and formate (FA) from the simultaneous conversion of glycerol and carbonate. For this purpose, here we developed a novel method for synthesis of Ru nanoparticles (NPs) supported on extremely rigid 3D graphitic nanoporous carbon (Ru/NCT, T = pyrolysis temperature). The Ru/NCT catalysts were prepared by in situ encapsulation of trimeric ruthenium cluster in ZIF-11 pores and followed by pyrolysis. The pyrolysis temperature affected the size and crystallinity of Ru NPs and textural property of ZIF-11-derived carbon. Optimization of the reaction parameters such as CO2 source, reaction temperature, reaction time and glycerol/carbonate ratio revealed that Ru/NCT showed significantly high turnover number (TON) and space-time yield (STY) for the desired products (LA and FA). Moreover, Ru/NCT were stable even after three consecutive recycle tests at harsh reaction condition without leaching of active metal and notable structural change. The correlation of the reaction performance, detailed characterizations and DFT calculation revealed that high crystallinity and large particle size of Ru exhibit superior activity towards the combined dehydrogenation-hydrogenation to the desired products, LA and FA.

P-33: Formation of lactate and formate from glycerol and carbonates over supported Pt catalysts Anil H. Valekar, Kyung-Ryul Oh, Young Kyu Hwang Research Center for Nanocatalysts, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea

Hydrogenation of CO2 to formic acid (FA) is one of the viable processes of utilizing abundant CO2. However, direct activation of CO2 often required high external energy inputs such as high temperature and pressure due to its low solubility in aqueous medium. Carbonates and bicarbonates were preferred over direct use of CO2 due to their high solubility in water. Additionally, H2, a common reductant mainly produced from natural gas, which is neither cheap nor sustainable. Biomass derived alcohols or polyols having high potential as H2 source are one of the major byproducts in the biofuels industry. Hence, it is highly desirable to upgrade such biomass wastes into value-added chemicals to improve biofuel economics. Therefore, transfer hydrogenation (TH) of CO2 using glycerol as H2 source to afford formic and lactic acid is a highly attractive path to valorizing two waste streams (Scheme 1) [1, 2]. In our study, we utilized various supported Pt catalysts for simultaneous production of lactate and formate from glycerol and carbonates by following ‘two bird one stone’ strategy (Table 1). As can be seen from Table 1, Pt on gamma alumina support (Pt/γ-Al2O3) shown the best performance among the tested catalysts. It has been reported that glycerol strongly adsorb on γ-Al2O3 by forming multidentate alkoxide surface species with strong Lewis acid sites [3]. This could be the key step to initiate dehydrogenation of glycerol to produce hydrogen and lactic acid. Along with this, other properties of support, such as specific surface area, pore size distribution, acid-base property, may have great effects on metal support interaction, dispersion and size of Pt nanoparticles and diffusion of reactants in aqueous phase, and thus influence the catalytic performance of the catalyst. Several reaction parameters were optimized to reach maximum yield up to 50% for lactate and 30% for formate from glycerol and

K2CO3, respectively over Pt/γ-Al2O3. Catalyst was recycled up to four cycles with little changes in product yields and further characterized by XRD, STEM and XPS analysis to understand structural, morphological and chemical changes in used catalyst. Reaction pathway was proposed based on the product distribution data obtained from HPLC analysis. Scheme 1: Proposed reaction pathway for conversion of glycerol to lactate and K2CO3 to formate with hydrogen transfer.

Table 1 Lactate and formate production from glycerol and K2CO3 over Pt catalysts.

Entry Catalyst Glycerol Yield (%) TON conv.(%) Lactate Formate Lactate Formate

1 No 4 1 0 ------

2 Pt/ZrO2 24 8 4 328 43

3 Pt/ZnO 50 9 6 322 52

4 Pt/C 42 12 5 421 43

5 Pt/γ-Al2O3 25 13 13 459 116

Reaction conditions- T- 180 ºC, t- 12h, N2- 400 psi, Cat.-0.2g, Glycerol–2M, K2CO3-0.5M in 50 ml of water. References [1] J. M. Heltzel, M. Finn, D. Ainembabazi, K. Wang and A. M. Voutchkova-Kostal, Chem. Commun., 54 (2018) 6184. [2] J. Su, L. Yang, X. Yang, M. Lu, B. Luo and H. Lin, ACS Sustainable Chem. Eng. 3 (2015) 195. [3] J. R. Copeland, I. A. Santillan, S. M. Schimming, J. L. Ewbank and C. Sievers, J. Phys. Chem. C, 117 (2013) 21413.

P-34: Simultaneous production of syngas and carbon monoxide by

cyclic methane decomposition and CO2 oxidative regeneration in

NiFe2O4/Al2O3 Yikyeom Kim, Hyun Suk Lim, Minbeom Lee, Jae W. Lee Department of Chemical & Biomolecular Engineering, Korea Advanced Institute of Science and Technology 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea

For the conversion of greenhouse gases including CH4 and CO2, cyclic reaction scheme was adopted and relatively cheap Ni-Fe-Al oxide (NiFe2O4/Al2O3) was utilized in this study as an oxygen and carbon carrier considering that methane decomposition and catalyst regeneration by CO2 can yield the higher productivity and versatile product composition. CH4 feedstock was partially replaced with CO2 and the amount was optimized to tune the H2/CO ratio in the syngas. The Ni-Al oxide suffered from the gradual deactivation due to the particle agglomeration caused by methane decomposition and subsequent catalyst regeneration. Although Fe-Al oxide exhibited a stable performance during redox cycling, sudden CH4 conversion decline was observed when the amount of CO2 co-feeding exceeded a certain point. It was found that the simultaneous use of Ni and Fe can overcome these problems and the Ni-Fe- Al oxide was selected as an optimal particle for the process. The formation of a spinel phase with Fe suppressed the agglomeration of Ni. CH4 activation was maintained in the Ni-Fe-Al oxide under high CO2 partial pressure. It was also revealed that the reactivity of surface carbon with CO2 can be affected by the crystallinity of carbon and the type of metal oxide used.1 Reference [1] Kim, Y.; Lim, H. S.; Lee, M.; Lee, J. W. Ni-Fe-Al Mixed Oxide for Combined Dry Reforming and Decomposition of Methane with CO2 Utilization. Catal. Today 2020, No. January, 1–10. https://doi.org/10.1016/j.cattod.2020.02.030.

P-36: Pilot-scale plant for synthesis of methanol, methane and dimethyl ether from carbon dioxide and green hydrogen Stefano Sollai, Mauro Mureddu, Francesca Ferrara, Gabriele Calì, Marcella Fadda, Enrico Maggio, Alberto Pettinau Sotacarbo S.p.A., Carbonia, ITALY The carbon dioxide concentration in the atmosphere is the main responsible for global warming and climate changes. Research has been directed to its reduction and particularly in the field of carbon capture, storage and/or utilization technologies. In this scenario Sotacarbo has started a series of projects to study and develop the production of gaseous and liquid fuels from carbon dioxide through the catalytic hydrogenation process for energy storage applications. In particular, Sotacarbo has developed a project framed by the 2019-2021 Plan of the Italian Ministry of Economic Development (which defines the general purpose, themes and funding for the R&D activities on the national electric system). The project consists on the design, building and experimentation of a new experimental pilot-scale plant for the study of the CO2 catalytic hydrogenation in order to obtain liquid and gaseous fuels.

The plant has been designed for the production of methanol (CH3OH), methane

(CH4) and dimethyl ether (DME, CH3OCH3) from carbon dioxide and green hydrogen. The setup has been designed for a production of 5 kg/h (120 kg/day) of final product. The gas mixture entering the reaction section is obtained through pure gases from cylinders. For flexibility purposes, the plant has been equipped with two different reactors, fed by the same gas feeding system: a single tube reactor and a multitubular reactor. The maximum operating conditions will be of 60 bar at 350 °C or 30 bar at 450 °C. A gas-liquid separation system has been provided consisting of three vessels: a wax trap for heavy by-products recovery, a high-pressure separator for efficient separation of permanent gases (non-reacted gases and other gaseous compounds) from liquid phases, and a low-pressure separator to isolate aqueous, organic and gas phases. In order to increase the reaction efficiency, a portion of the gas effluents is recirculated back to the reactor through a gas compressor. The H2/(CO2+CO) ratio at the reactor inlet is accordingly adjusted on the basis of the recirculation flow composition. The system is equipped with a gas chromatograph and a NDIR analyzer for the analyses of the samples collected. This work presents an overview of the whole project, with details on the setup and the main goals of the first experimental campaign.

P-37: The size effect of silicalite-1 on CrOx/silicalite-1 for the oxidative dehydrogenation of propane with carbon dioxide Jian Wang, Yong-Hong Song, Zhao-Tie Liu, Zhong-Wen Liu* Key Laboratory of Syngas Conversion of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi’an 710119, China

Propene is one of the most important primary blocks in the petrochemical industry for the production of a variety of chemicals and materials. The oxidative dehydrogenation of propane with CO2 (CO2-ODP) has drawn much attention due to the alleviated limitation of thermodynamics equilibrium and the effective utilization of the greenhouse gas of CO2.

Although the supported chromium oxides (CrOx) are important catalysts for CO2- ODP, the rational catalyst design is still challenged by the rapid deactivation of the catalysts. In this work, based on the previous work in our group, the further modification of the 3CrOx/silicalite-1 catalyst by adjusting the particle sizes of silicalite-1 and optimizing the CrOx structure leads to at least a twofold enhancement in the catalytic stability for CO2-ODP. Importantly, the fine control of CrOx structure can facilitate the coke removing over CrOx oxides, and promotes the migration of the coke from CrOx oxides to silicalite-1 support, both the factors of which are favorable for improving the stability of 3CrOx/silicalite-1 for CO2-ODP.

Acknowledgements

The authors thank the financial supports of the National Natural Science Foundation of China (21636006) and the Fundamental Research Funds for the Central Universities (GK201901001 and 2017CBZ002).

References

[1] G. M. Li, C. Liu, X. J. Cui, et al., Green Chem. 2021, 23(2): 689-707 [2] J. Wang, Y. H. Song, Z. T. Liu, et al., Appl. Catal. B: Environ. 2021, 297: 120400

P-38: Conversion of CO2 to synthetic fuel vs fossil-based fuel: comparison of environmental performances via LCA Lim Pin, Chen Luwei, Chang Jie, Khoo Hsien Hui* Institute of Chemical and Engineering Sciences (ICES), Agency for Science, Technology and Research (A*STAR) 1 Pesek Road, Jurong Island, Singapore 627833, Singapore

Carbon capture and utilization (CCU) represents an integral avenue for carbon mitigation strategies and decarbonisation. In alignment with the aim of reducing greenhouse gas emissions and our reliance on fossil-fuel usage, CO2 can be recycled as a carbon resource and utilized to produce synthetic jet fuel through Fischer-Tropsch synthesis. To provide an overall assessment of the sustainability of the CO2-to- kerosene process, Life cycle assessment (LCA) was used to determine the potential environmental profile of the potential CCU pathways as per a simplified downstream process in comparison with fossil-based fuel, with the functional amount being defined as 1 kg of aviation-standard kerosene jet fuel. In this study, life cycle impact assessment method CML 2001 was applied to evaluate the following four environmental impacts: Global warming potential (GWP), Acidification potential (AP), Human toxicity potential (HTP), and Fossil Fuel usage. GWP results demonstrate that CCU-based kerosene has potential to reduce greenhouse gas emissions by ~7 kg CO2-eq per kg, as compared to the equivalent fossil-based product. Additionally, AP and HTP results were found to be reduced by about 75% and 99% respectively via CO2-to-kerosene conversion, while Fossil fuel usage, measured as total MJ, was reduced by half.

P-39: Promotional effects of CeO2 on Pt-Sn/SiO2 for oxidative

dehydrogenation of propane with CO2 Li Wang, Guo-Qing Yang, Heng-Bo Zhang, Zhong-wen Liu* Key Laboratory of Syngas Conversion of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi’an 710062, China *e-mail: [email protected]

The oxidative dehydrogenation of propane with CO2 (CO2-ODP) is a sustainable route for producing propylene with the tandem conversion of CO2 to the value-added [1] CO . To date, the majority of the potential catalysts for CO2-ODP is originated from those for the propane dehydrogenation (PDH), the activity and stability of which are still far below the requirement for the industrial application. Thus, the development of an efficient catalyst is highly desired to advance the green CO2-ODP process.

Moreover, taking the redox nature of the CO2-ODP reaction into account, the activation of C-H bonds in propane must be synchronized with that of the C=O bonds in CO2 molecules irrespective of the catalysts employed, which are important topics for the heterogeneous catalysis. [2] Based on our understanding on the redox properties of CeO2 , in this work, the promotional effect of CeO2 on Pt-Sn/SiO2 for CO2-ODP was investigated by preparing the catalysts with the simple impregnation method. The reaction results indicate that the conversion of both propane and CO2 was significantly increased by adding CeO2 into Pt-Sn/SiO2 while the selectivity of propylene was still kept over 90%. From the characterization results of XRD, TPR, XPS, Raman, and DRIFTS, the strong electronic interactions between CeO2 and Pt led to a higher dispersion of Pt, and the lattice oxygen over CeO2 consumed during activating propane was replenished with the activation of CO2, the detailed reaction and mechanistic results of which will be presented. Acknowledgements The authors thank the financial supports of the National Natural Science Foundation of China (21636006) References

(1) P.Michorczyk, K. Zeńczak-Tomera, et al., Journal of CO2 Utilization, 2020, 36: 54-63 (2) Z. W. Liu, C. Wang, et al., ChemSusChem, 2011, 4(3): 341-345 P-40: Rational Design of Solid Adsorbents for Post-Combustion

CO2 Capture via Temperature Swing Woosung Choi, Jongbeom Park, Chaehoon Kim, and Minkee Choi* Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701, Korea.

Linear/branched polyethyleneimines (PEI) and their modified structures have been widely used to prepare CO2 adsorbents due to their low material cost and high amine content. However, few studies have been carried out to comprehensively understand the effects of polymer structures on the properties of adsorbents. In this study, we rigorously investigated the effects of polymer structures on the CO2 adsorption capacity, kinetics, adsorbent stability, and regeneration heat of adsorbents using four amine polymers with different molecular weights, amine distributions, and ppm-level metal impurities. Linear tetraethylenepentamine (TEPA) exhibited the highest CO2 adsorption capacity due to its low tertiary amine content. However, unlike common intuition, the high CO2 capacity of TEPA did not lead to high energy efficiency of the

CO2 capture process because of excessively strong CO2 adsorption and substantial

H2O co-adsorption. Furthermore, the use of TEPA led to the slowest CO2 adsorption kinetics and the fastest thermochemical degradation. In contrast, epoxide- functionalized branched PEI (EB-PEI) exhibited the lowest CO2 capacity, but enabled the most energy-efficient CO2 capture due to suppressed H2O co-adsorption. It also exhibited the fastest adsorption kinetics and the highest stability. The present results indicated that the CO2 adsorption capacity of adsorbents should not be overemphasized for CO2 adsorbent development and other important engineering aspects (e.g., adsorption kinetics, thermochemical stability, and regeneration heat) need to be considered collectively. References 1. W. Choi, et al., Nature Communications, 2016, 7, 12640 2. K. Min, et al., ChemSusChem, 2017, 10, 2518 3. K. Min, W. Choi, C. Kim, M. Choi*, Nature Communications, 2018, 9, 726 4. K. Min, W. Choi, C. Kim, M. Choi*, ACS Appl. Mater. Interfaces 2018, 10, 23825

P-41: Design of porous carbons for high-pressure carbon dioxide adsorption Jong-Hoon Lee and Soo-Jin Park* *Department of Chemistry, Inha University, 100 Inharo, Inchen 22212, Republic of Korea

Excessive carbon dioxide (CO2) emission from rapid industrial growth impose the efficient technology for CO2 reduction. One of the promising technology for CO2 mitigation is physical or chemical adsorption using highly porous materials. Design of efficient adsorbent is important to satisfy the increasing demand for carbon capture and separation (CCS). There are various types of adsorption materials studied for CCS. Porous carbons are one of the promising contenders for CCS adsorbents by their high specific surface area, tunable pore structures, moderate heat fo adsorption, and high chemical stability. The high CO2 uptakes with moderate regeneration ability make these porous carbons promising adsorbents in environmental applications.

In this work, precursors were carbonized at 900 ℃, 1 hr, and N2 flow conditions. After carbonized, porous carbons was synthesized by chemical activation. The effect on quantity of activation reagents was investigated by experience of carbon precursor/chemical reagent mass ratio. The structural information of the activated carbons was measured by X-ray diffraction (XRD) patterns and scanning electron microscopy (SEM). The N2 adsorption-desorption isotherms were measured at 77 K and calculated by Brunauer-Emmett-Teller (BET) equation. CO2 storage capacity was evaluated with a Model BEL-HP instrument (BEL Co., Ltd., Japan) at 298 K and 35 bar.

P-42: A study of efficient micropore size on carbon dioxide physisorption of pine cone-based carbonaceous materials at different temperatures Choong-Hee Kim, , Seul-Yi Lee*, and Soo-Jin Park* *Department of Chemistry, Inha University, 100 Inharo, Inchen 22212, Republic of Korea

Biomass-based activated carbons (ACs) were widely used as a CO2 capture material. Most plant-based biomass has a phytoliths component mainly composed of silica, which is being an obstacle for developing porosity of ACs. Research has rarely been done on the silica elimination process for increasing porosity of ACs. To this end, our research focuses on optimizing micropores of ACs through silica elimination sequence. We prepared ACs using pre-carbonized pine cones. Pre-carbonized pine cones were prepared (CPC). One is prepared by KOH activation and subsequent silica removal (CPC-CA-SE/ACs) process, the other is undergone silica removal prior to KOH activation (CPC-SE-CA/ACs). The optimized sample, exhibited the highest specific surface area (2047 m2 g-1) and total pore volume (0.886 cm3 g-1) and the -1 maximum adsorption amount of 6.57 mmol g of CO2 at 273 K and 1 bar was found in CPC-SE-CA/ACs. In particular, there was a significant difference in the micro and meso porosity of CPC-CA/SE/ACs and CPC-SE-CA/ACs. Depending on the adsorption temperatures, we found that effective pore size for CO2 uptake was different. -1 Also, optimized samples achieved a high CO2 uptake of 33.2 mg g in flue gas conditions (15% CO2/85% N2) and good regeneration property throughout 10 adsorption–desorption cycles at 313 K. Therefore, our study provides evidence on the sequence of the silica elimination process and chemical activation in biomass-based activated carbons which affects the CO2 capture and physisorption behavior by improving porosity.