Where Are We to Day in the Overlap Between Homogeneous And
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Opportunities for Catalysis in the 21St Century
Opportunities for Catalysis in The 21st Century A Report from the Basic Energy Sciences Advisory Committee BASIC ENERGY SCIENCES ADVISORY COMMITTEE SUBPANEL WORKSHOP REPORT Opportunities for Catalysis in the 21st Century May 14-16, 2002 Workshop Chair Professor J. M. White University of Texas Writing Group Chair Professor John Bercaw California Institute of Technology This page is intentionally left blank. Contents Executive Summary........................................................................................... v A Grand Challenge....................................................................................................... v The Present Opportunity .............................................................................................. v The Importance of Catalysis Science to DOE.............................................................. vi A Recommendation for Increased Federal Investment in Catalysis Research............. vi I. Introduction................................................................................................ 1 A. Background, Structure, and Organization of the Workshop .................................. 1 B. Recent Advances in Experimental and Theoretical Methods ................................ 1 C. The Grand Challenge ............................................................................................. 2 D. Enabling Approaches for Progress in Catalysis ..................................................... 3 E. Consensus Observations and Recommendations.................................................. -
Preparation and Characterization of Iridium Hydride and Dihydrogen Complexes Relevant to Biomass Deoxygenation
Preparation and Characterization of Iridium Hydride and Dihydrogen Complexes Relevant to Biomass Deoxygenation Jonathan M. Goldberg A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy University of Washington 2017 Reading Committee: D. Michael Heinekey, Chair Karen I. Goldberg, Chair Brandi M. Cossairt Program Authorized to Offer Degree: Department of Chemistry © Copyright 2017 Jonathan M. Goldberg University of Washington Abstract Preparation and Characterization of Iridium Hydride and Dihydrogen Complexes Relevant to Biomass Deoxygenation Jonathan M. Goldberg Chairs of the Supervisory Committee: Professor D. Michael Heinekey Professor Karen I. Goldberg Department of Chemistry This thesis describes the fundamental organometallic reactivity of iridium pincer complexes and their applications to glycerol deoxygenation catalysis. These investigations provide support for each step of a previously proposed glycerol deoxygenation mechanism. Chapter 1 outlines the motivations for this work, specifically the goal of using biomass as a chemical feedstock over more common petroleum-based sources. A discussion of the importance of transforming glycerol to higher value products, such as 1,3-propanediol, is discussed. Chapter 2 describes investigations into the importance of pincer ligand steric factors on the coordination chemistry of the iridium metal center. Full characterization of a five-coordinate iridium-hydride complex is presented; this species was previously proposed to be a catalyst resting state for glycerol deoxygenation. Chapter 3 investigates hydrogen addition to R4(POCOP)Ir(CO) R4 3 t i R4 R4 3 [ POCOP = κ -C6H3-2,6-(OPR2)2 for R = Bu, Pr] and (PCP)Ir(CO) [ (PCP) = κ -C6H3-2,6- t i (CH2PR2)2 for R = Bu, Pr] to give cis- and/or trans-dihydride complexes. -
Rational Ligand Design for U(VI) and Pu(IV)* by Géza Szigethy BA
Rational Ligand Design for U(VI) and Pu(IV)* by Géza Szigethy B.A. (Princeton University), 2004 A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Chemistry in the Graduate Division of the University of California, Berkeley Committee in charge: Professor Kenneth N. Raymond, Chair Professor Richard A. Andersen Professor Garrison Sposito Fall 2009 * This research and the ALS are supported by the Director, Office of Science, Office of Basic Energy Sciences (OBES), and the OBES Division of Chemical Sciences, Geosciences, and Biosciences of the U.S. Department of Energy at LBNL under Contract No. DE-AC02- 05CH11231. Rational Ligand Design for U(VI) and Pu(IV) by Géza Szigethy B.A. (Princeton University), 2004 A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Chemistry in the Graduate Division of the University of California, Berkeley Committee in charge: Professor Kenneth N. Raymond, Chair Professor Richard A. Andersen Professor Garrison Sposito Fall 2009 Rational Ligand Design for U(VI) and Pu(IV) Copyright © 2009 Géza Szigethy Abstract Rational Ligand Design for U(VI) and Pu(IV) by Géza Szigethy Doctor of Philosophy in Chemistry University of California, Berkeley Professor Kenneth N. Raymond, Chair Nuclear power is an attractive alternative to hydrocarbon-based energy production at a time when moving away from carbon-producing processes is widely accepted as a significant developmental need. Hence, the radioactive actinide power sources for this industry are necessarily becoming more widespread, which is accompanied by the increased risk of exposure to both biological and environmental systems. -
1 the Structure and Reactivity of Single and Multiple
1 1 The Structure and Reactivity of Single and Multiple Sites on Heterogeneous and Homogeneous Catalysts: Analogies, Differences, and Challenges for Characterization Methods Adriano Zecchina , Silvia Bordiga , and Elena Groppo 1.1 Introduction The content of this book is specifi cally devoted to a description of the complexity of the catalytic centers (both homogeneous and heterogeneous) viewed as nanoma- chines for molecular assembling. Although the word “ nano ” is nowadays some- what abused, its use for catalysts science (as nanoscience) is fully justifi ed. It is a matter of fact that (i) to perform any specifi c catalytic action, the selective catalyst must necessarily possess sophisticated structure where substrates bonds are broken and formed along a specifi c path and (ii) the relevant part of this structure, usually constituted by a metal center or metal cluster surrounded by a sphere of ligands or by a solid framework or by a portion of functionalized surface, often reaches the nanometric dimension. As it will emerge from the various chapters, this vision is valid for many types of selective catalysts including catalysts for hydrogenation, polymerization, olygomerization, partial oxidation, and photocata- lytic solar energy conversion. Five chapters are devoted to the above - mentioned reactions. From the point of view of the general defi nition, homogeneous and heterogeneous selective catalysts can be treated in the same way. As homogeneous selective catalysts are concerned, the tridimensional structure surrounding the metal center can be organized with cavitand shape, while for heterogeneous cata- lysts the selectivity is the result of an accurate design and synthesis of the frame- work structures (often microporous and crystalline) where the sites are anchored. -
Osmium(II)–Bis(Dihydrogen) Complexes Containing Caryl,CNHC– Chelate Ligands: Preparation, Bonding Situation, and Acidity
Osmium(II)–bis(Dihydrogen) Complexes Containing Caryl,CNHC– Chelate Ligands: Preparation, Bonding Situation, and Acidity. Tamara Bolaño,† Miguel A. Esteruelas,*,† Israel Fernández,‡ Enrique Oñate,† Adrián Palacios,† Jui-Yi Tsai,√ and Chuanjun Xia√ †Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Centro de Innova- ción en Química Avanzada (ORFEO – CINQA), Universidad de Zaragoza – CSIC, 50009 Zaragoza, Spain ‡Departamento de Química Orgánica, Facultad de Ciencias Químicas, Centro de Innovación en Química Avanzada (ORFEO – CINQA), Universidad Complutense de Madrid, 28040 Madrid, Spain √Universal Display Corporation, 375 Phillips Boulevard, Ewing, New Jersey 08618, United States Supporting Information Placeholder i ABSTRACT: The hexahydride complex OsH6(P Pr3)2 (1) reacts with the BF4-salts of 1-phenyl-3-methyl-1-H-benzimidazolium, 1- phenyl-3-methyl-1-H-5,6-dimethyl-benzimidazolium, and 1-phenyl-3-methyl-1-H-imidazolium to give the respective trihydride- 2 i osmium(IV) derivatives OsH3( -Caryl,CNHC)(P Pr3)2 (2–4). The protonation of these compounds with HBF4·OEt2 produces the re- 2 2 i duction of the metal center and the formation of the bis(dihydrogen)-osmium(II) complexes [Os( -Caryl,CNHC)(η -H2)2(P Pr3)2]BF4 (5–7). DFT calculations using AIM and NBO methods reveal that the Os–NHC bond of the Os-chelate link tolerates a significant π- backdonation from a doubly occupied dπ(Os) atomic orbital to the pz atomic orbital of the carbene carbon atom. The π-accepting capacity of the NHC unit of the Caryl,CNHC-chelate ligand, which is higher than those of the coordinated aryl group and phosphine ligands, enhances the electrophilicity of the metal center activating one of the coordinated hydrogen molecules of 5–7 towards the water heterolysis. -
Selectivity of C-H Activation and Competition Between C-H and C-F Bond Activation at Fluorocarbons
This is a repository copy of Selectivity of C-H activation and competition between C-H and C-F bond activation at fluorocarbons. White Rose Research Online URL for this paper: https://eprints.whiterose.ac.uk/133766/ Version: Accepted Version Article: Eisenstein, Odile, Milani, Jessica and Perutz, Robin N. orcid.org/0000-0001-6286-0282 (2017) Selectivity of C-H activation and competition between C-H and C-F bond activation at fluorocarbons. Chemical Reviews. pp. 8710-8753. ISSN 0009-2665 https://doi.org/10.1021/acs.chemrev.7b00163 Reuse Items deposited in White Rose Research Online are protected by copyright, with all rights reserved unless indicated otherwise. They may be downloaded and/or printed for private study, or other acts as permitted by national copyright laws. The publisher or other rights holders may allow further reproduction and re-use of the full text version. This is indicated by the licence information on the White Rose Research Online record for the item. Takedown If you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing [email protected] including the URL of the record and the reason for the withdrawal request. [email protected] https://eprints.whiterose.ac.uk/ revised May 2017 Selectivity of C-H activation and competition between C-H and C-F bond activation at fluorocarbons Odile Eisenstein,* ‡ Jessica Milani, and Robin N. Perutz* ‡ Institut Charles Gerhardt, UMR 5253 CNRS Université Montpellier, cc 1501, Place E. Bataillon, 34095 Montpellier, France and Centre for Theoretical and Computational Chemistry (CTCC), Department of Chemistry, University of Oslo, P.O. -
1 5.03, Inorganic Chemistry Prof. Daniel G. Nocera Lecture 11
5.03, Inorganic Chemistry Prof. Daniel G. Nocera Lecture 11 Apr 11: Hydride and Dihydrogen Complexes – – 2 Hydride and dihydrogen are both 2e donors, H (1s ) and H2 (σ1s2) Hydride complexes are synthesized by: (1) Replace halide with hydride using hydride transfer reagents: (2) Heterolytic cleavage of a dihydrogen complex: (3) Oxidative-addition of hydrogen to a metal complex: There are some general features of H2 oxidative-addition: • cis addition – – • 16e complexes or less add H2 (since 2e s are added to the metal complex) • bimolecular rate law (rate = k [IrL2Cl(CO)] [H2]) ‡ • ∆H = 11 kcal/mol (little H–H stretch in the transition state recall that ‡ BDE(H2) = 104 kcal/mol), and a ∆S = 21 eu – – – – • rate decreases along the series X = I > Br > Cl (100 ; 14 : 0.9) • little isotope effect, kH / kD = 1.09 1 For the oxidative-addition reaction, there are two possibilities for the transition state: 1 an H2 intermediate 2 a three-center transition state Both reaction pathways are viable for oxidative-addition (and the reverse reaction, reductive-elimination). For some metal complexes, the “arrested” addition product can be isolated—the dihydrogen complex is obtained as a stable species that can be put in a bottle. Kubas first did this in 1984 with the following reaction: 2 Several observables identify this as an authentic dihydrogen complex vs. a dihydride: • d(H—H) = 0.84 Å (as measured from neutron diffraction). This distance is near the bond distance of free H2, d(H—H) = 0.7414 Å. –1 • a symmetric H2 vibration is observed, ν(H—H) = 2,690 cm , as compared –1 to ν(H—H) = 4,300 cm in free H2. -
Structural Analysis and Separation of Lanthanides With
Full Paper Chemistry—A European Journal doi.org/10.1002/chem.202002653 & CoordinationChemistry The Earlier the Better:Structural Analysis and Separation of Lanthanides with Pyrroloquinoline Quinone HenningLumpe+,[a] Annika Menke+,[a] Christoph Haisch,[b] Peter Mayer,[a] Anke Kabelitz,[c] Kirill V. Yusenko,[c] Ana Guilherme Buzanich,[c] Theresa Block,[d] Rainer Pçttgen,[d] Franziska Emmerling,[c] and Lena J. Daumann*[a] Abstract: Lanthanides (Ln) are critical raw materials,howev- ronment.The complex crystallizes as an inversion symmetric er,their mining and purification have aconsiderable nega- dimer,Eu2PQQ2,with binding of Eu in the biologically rele- tive environmental impact andsustainable recycling and vant pocket of PQQ. LnPQQ and Ln1Ln2PQQ complexes separation strategies for these elements are needed. In this were characterized by using inductively coupled plasma study,the precipitationand solubility behavior of Ln com- mass spectrometry (ICP-MS), infrared (IR) spectroscopy, 151Eu- plexes with pyrroloquinoline quinone (PQQ), the cofactor of Mçssbauer spectroscopy,X-ray total scattering, andextend- recently discovered lanthanide (Ln) dependent methanol de- ed X-ray absorption fine structure (EXAFS). It is shown that a hydrogenase (MDH)enzymes, is presented. In this context, natural enzymatic cofactor is capable to achieveseparation the molecular structure of abiorelevant europium PQQ com- by precipitationofthe notoriously similar,and thusdifficult plex was for the first time elucidated outsideaprotein envi- to separate, lanthanides to some extent. Introduction also called “vitamins, or seeds of technology” and the global demand of rare earth oxides is growing steadily.[1] Unlike their Rare earth elements (REE) include the elements 21Sc, 39Yand name suggests, REE are not particularly rare and the occur- 57La, in addition to the 14 lanthanides (Ln) from 58Ce to 71Lu. -
Heterogeneous Catalytic Oligomerization of Ethylene
Heterogeneous Catalytic Oligomerization of Ethylene Oliver Dennis Jan A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy University of Washington 2017 Reading Committee: Fernando Resende, Chair Rick Gustafson Anthony Dichiara Program Authorized to Offer Degree: School of Environmental and Forest Sciences © Copyright 2017 Oliver Dennis Jan ii University of Washington Abstract Heterogeneous Catalytic Oligomerization of Ethylene Oliver Dennis Jan Chair of the Supervisory Committee: Assistant Professor Fernando Resende School of Environmental and Forest Sciences Throughout this work, we report results for the oligomerization of ethylene over Ni-Hβ in a packed bed reactor. We performed a parameterized study over temperature (30ºC-190ºC), pressure (8.5-25.6 bar), and weighted hourly space velocity (2.0-5.5 hr-1). We observed that the ethylene conversion increased with reaction pressure due primarily to the slower velocities at higher pressures. Increasing the temperature of the reactor led to the formation of larger oligomers and coke, but its effect on the conversion was small. The space velocity played an important role on ethylene conversion and product selectivity, with higher conversions observed at lower space velocities and higher selectivities to butene at higher space velocities. We also conducted a long experiment to determine the activity of the Ni-Hβ catalyst over 72 hours-on-stream at 19.0 bar partial pressure of ethylene, 120ºC, and 3.1 hr-1 WHSV. We observed that catalyst deactivation occurred only during the startup period largely due to coke formation. Despite this initial iii deactivation, negligible coke formation occurred after 8 hours time-on-stream, as the conversion remained steady at 47% for the duration of the experiment. -
Molecular Beam Epitaxy in the Lithium-Niobium-Oxygen System
MOLECULAR BEAM EPITAXY IN THE LITHIUM-NIOBIUM-OXYGEN SYSTEM by Mario Petrucci Department of Electrical and Electronic Engineering, University College London. A thesis submitted to University College, University of London for the degree of Doctor of Philosophy. October, 1989 1 ProQuest Number: 10610929 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a com plete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. uest ProQuest 10610929 Published by ProQuest LLC(2017). Copyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States C ode Microform Edition © ProQuest LLC. ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106- 1346 To the memory of my father, Vincenzo Petrucci. 'We work not only to produce But to give value to time." Eugene Delacroix "Oh, Mr. Scientist: you take what you see And fashion a wondrous soliloquy; But greater magic is forged in what you write: Where night becomes day and day becomes night!" 2 ABSTRACT The N b -L i-0 materials system offers an extensive combination of properties useful to integrated optics. N b ^ and L iN b 03 already have applications in waveguiding devices, such as electro-optic modulators, Fresnel lenses, and SAW transducers. In several cases, however, it would be desirable to grow these oxides on lattice-matched substrates as epitaxial thin films of controlled composition, crystallinity, and thickness: this thesis describes work aimed at achieving this goal. -
Basic Research Needs for Catalysis Science
Basic Research Needs for Catalysis Science Report of the Basic Energy Sciences Workshop on Basic Research Needs for Catalysis Science to Transform Energy Technologies May 8–10, 2017 Image courtesy of Argonne National Laboratory. DISCLAIMER This report was prepared as an account of a workshop sponsored by the U.S. Department of Energy. Neither the United States Government nor any agency thereof, nor any of their employees or officers, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of document authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Copyrights to portions of this report (including graphics) are reserved by original copyright holders or their assignees, and are used by the Government’s license and by permission. Requests to use any images must be made to the provider identified in the image credits. This report is available in pdf format at https://science.energy.gov/bes/community-resources/reports/ REPORT OF THE BASIC RESEARCH NEEDS WORKSHOP FOR CATALYSIS SCIENCE Basic Research Needs for Catalysis Science TO TRANSFORM ENERGY TECHNOLOGIES Report from the U.S. Department of Energy, Office of Basic Energy Sciences Workshop May 8–10, 2017, in Gaithersburg, Maryland CHAIR: ASSOCIATE CHAIRS: Carl A. -
Low Cost/Waste Catalyst for Fatty Acid Methyl Ester Production
Article Number: 2AEBF76 A Paper presented at the 39th CSN Annual International Conference, Workshop and Exhibition, Rivers State University of Science and Technology, Port Harcourt, Nigeria. 18th – 23rd September 2016 Copyright ©2018 Author(s) retain the copyright of this article Conference Proceedings http://www.proceedings.academicjournals.org/ Full Length Research Paper Low cost/waste catalyst for fatty acid methyl ester production M. O. Ekeoma1*, P. A. C. Okoye2 and V. I. E. Ajiwe2 1Department of Chemistry, College of Physical and Applied Sciences, Michael Okpara University of Agriculture, Umudike, P. M. B. 7267, Umuahia, Abia State, Nigeria. 2Department of Pure and Industrial Chemistry, Faculty of Physical Sciences, Nnamdi Azikiwe University, Awka, Anambra State, Nigeria. Non-edible crude karanj (Pongamia pinnata) oil (CKO) with high free fatty acid (FFA) content was used as effective renewable feedstock for fatty acid methyl ester (FAME) production. Calcium feldspar clay, a rare compositional variety of plagioclase clay, a low cost, abundant earth resource, containing over 90% CaO and belonging to the class of anorthite clay was used as heterogeneous catalyst in direct conversion of high FFA crude karanj oil to fatty acid methyl esters. The efficiency of the catalyst was made possible by the structural rearrangement of the mixed metal oxides' content of the catalyst at prolonged high temperatures, a behaviour characteristic of glass transitions and properties of amorphous phases of plagioclase feldspar, and thus was transformed into solid acid particles such as acidic mesoporous aluminium silicate mixed oxides. Optimum FAME yield of 98.97% was obtained at 4 h reaction time, 6 wt% catalyst loading, 9:1 methanol to CKO molar ratio and at methanol reflux temperature.