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Theory of Lewis Acid Zeolite Catalysis for the Conversion of Biomass-Derived Furanics : on the Effect of Multi-Site Cooperativity and Confinement

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Theory of Lewis Acid Zeolite Catalysis for the Conversion of Biomass-Derived Furanics : on the Effect of Multi-Site Cooperativity and Confinement Theory of Lewis acid zeolite catalysis for the conversion of biomass-derived furanics : on the effect of multi-site cooperativity and confinement Citation for published version (APA): Rohling, R. (2019). Theory of Lewis acid zeolite catalysis for the conversion of biomass-derived furanics : on the effect of multi-site cooperativity and confinement. Technische Universiteit Eindhoven. Document status and date: Published: 23/01/2019 Document Version: Publisher’s PDF, also known as Version of Record (includes final page, issue and volume numbers) Please check the document version of this publication: • A submitted manuscript is the version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. 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If the publication is distributed under the terms of Article 25fa of the Dutch Copyright Act, indicated by the “Taverne” license above, please follow below link for the End User Agreement: www.tue.nl/taverne Take down policy If you believe that this document breaches copyright please contact us at: [email protected] providing details and we will investigate your claim. Download date: 10. Oct. 2021 Theory of Lewis Acid Zeolite Catalysis for the Conversion of Biomass-Derived Furanics On the Effect of Multi-Site Cooperativity and Confinement PROEFSCHRIFT ter verkrijging van de graad van doctor aan de Technische Universiteit Eindhoven, op gezag van de rector magnificus prof.dr.ir F.P.T. Baaijens, voor een commissie aangewezen door het College voor Promoties, in het openbaar te verdedigen op woensdag 23 januari 2019 om 16:00 uur door Roderigh-IJsbrand Rohling geboren te Goes Dit proefschrift is goedgekeurd door de promotoren en de samenstelling van de promotiecommissie is als volgt: voorzitter: prof.dr.ir. D.C. Nijmeijer 1e promotor: prof.dr.ir. E.J.M. Hensen copromotor: dr. E.A. Pidko leden: prof.dr. R.A. Van Santen prof.dr. P.C.A. Bruijnincx (Universiteit Utrecht) prof.dr. E.J. Meijer (Universiteit van Amsterdam) dr.ir. A. Palmans adviseur: dr. R.E. Bulo (Universiteit Utrecht) Het onderzoek of ontwerp dat in dit proefschrift wordt beschreven is uitgevoerd in overeenstemming met de TU/e Gedragscode Wetenschapsbeoefening. II Opgedragen aan mijn broer, Rowin-Xandrijn Rohling III Roderigh-IJsbrand Rohling Theory of Lewis Acid Zeolite Catalysis for the Conversion of Biomass-Derived Furanics - On the Effect of Multi-Site Cooperativity and Confinement A catalogue record is available from the Eindhoven University of Technology Library ISBN: 978-90-386-4680-0 The work described in this thesis has been carried out at the Inorganic Materials and Catalysis group, Eindhoven University of Technology, The Netherlands. We acknowledge the Multiscale Catalytic Energy Conversion (MCEC) consortium for financial support and the Netherlands Organization for Scientific Research (NWO) for providing access to the supercomputer facilities. Printed by: Gildeprint – Enschede, The Netherlands Cover design: Roderigh-IJsbrand Rohling Copyright © 2018 by Roderigh-IJsbrand Rohling IV Contents Chapter 1 Introduction 1 Chapter 2 Theory and Methods 19 Chapter 3 An Active Alkali-Exchanged Faujasite Catalyst for 33 Para-Xylene Production via the One-Pot Diels- Alder Cycloaddition/Dehydration Reaction of 2,5- Dimethylfuran with Ethylene Chapter 4 Multi-Site Cooperativity in Alkali-Exchanged 57 Faujasites for the Production of Biomass-Derived Aromatics Chapter 5 Electronic Structure Analysis of the Diels-Alder 77 Cycloaddition Catalyzed by Alkali-Exchanged Faujasites Chapter 6 Mechanistic Insight into the [4+2] Diels-Alder 93 Cycloaddition over First Row d-Block Cation- Exchanged Faujasites Chapter 7 Evaluation of Real Space Bond Orders (DDEC6) 119 and Orbital Based Bond Strengths (COHP) for Chemical Bonding Analysis: Correlations, Applications and Limitations Chapter 8 Effect of Reactant Confinement in Zeolites on the 141 Reaction and Activation Entropy Chapter 9 Summary and Outlook 159 Appendices Supporting Information for Chapter 7 165 Acknowledgement 176 List of publications 179 Curriculum Vitae 181 V VI Chapter 1 Introduction Section 1.4. has been published in G. Li, C. Liu, R. Rohling, E.J.M. Hensen, E.A. Pidko, Lewis acid catalysis by Zeolites in C.R.A. Catlow, V. van Speybroeck & Rutger van Santen (Eds.), Modelling and Simulation in the Science of Micro- and Mesoporous Materials (p. 229-263). UK: Elsevier Ltd. 1 1.1. Zeolites Zeolites are crystalline aluminosilicates which are highly ordered, three- dimensional networks of molecular sized micropores. Zeolites were discovered in 1756 by the Swedish mineralogist Axel Fredrik Cronstedt. 1 He noticed that some minerals started moving upon heating due to the release of gas bubbles. He called these materials ‘boiling stones’ or ‘zeolites’, derived from the Greek words ζέω (zéō, to boil) and λίθος (líthos, stone). The material that he discovered, would gain significant importance in our society. For instance, zeolites are currently applied in the petrochemical industry for oil-processing, gas phase separation processes and even in household applications as water softeners in detergents. Over 225 topologically different natural and synthetic zeolites are known, of which three examples are shown in Figure 1.1a-c. 2 Figure 1.1a depicts part of the sodalite (SOD) zeolite, characterized by a regular stacking of spherical sodalite cages. Each sodalite cage consists of four- and six-membered rings (MR). In Figure 1.1b, the Faujasite (FAU) zeolite is shown, made up of sodalite-cages interconnected by double six-membered rings. Yet another example is given in Figure 1.1c. This depicts part of the silicalite-1 zeolite with MFI framework type. It is characterized by straight 10-MR intersecting with sinusoidal 10-MR channels. All zeolites consist - of [SiO 4] silicon- and [AlO 4] aluminum tetroxides which are the smallest building blocks. These species polymerize, crystallize and form pores and cages of molecular - dimensions. During the formation of these aluminosilicates, no two [AlO 4] can be neighbors. At least one [SiO 4] unit has to separate them. This is known as the Löwenstein rule of ‘aluminum avoidance’. 3 Consequently, the Si/Al-ratio of zeolites can never be lower than unity. Figure 1.1. The framework of SOD, FAU and MFI are shown in (a), (b) and (c), respectively. An acid site is schematically depicted in (d). The active site concentration depends on the aluminum-content, with in (e) a high-silica faujasite zeolite (Si/Al = 47) with an isolated site and in (f) a high active site density due to the aluminum-rich framework (Si/Al = 2.4). 2 The characteristic shape of the molecular sized cages and pores enable shape- selective chemical transformations of adsorbed guest molecules. Three types of shape-selectivity are distinguished, being reactant, transition state and product selectivity. 4 The first type of selectivity has a sieving effect: reactants with sizes exceeding those of the micropores and cages are not able to enter the zeolite. Transition state selectivity results in a specific reaction path being blocked due to geometrical constraints imposed by the framework around the active site on the transition state of that particular pathway. Product selectivity is based on specific products being trapped within the zeolite such that these compounds have to isomerize before they can leave the microporous host. The catalytic activity of aluminosilicates arises from their acidic properties. This is caused by the substitution of Si 4+ with Al 3+ , giving rise to a net negative charge. This net negative charge has to be compensated. Such charge compensation can be achieved by protons, alkali or d-block metal cations, or organic cations, Figure 1.1d. The amount of Al 3+ substitutions affects the framework basicity and the active site density (Figure 1.1e and Figure 1.1f). 5 If protons counterbalance the negative charge, the material acts as a strong Brønsted acid. When the charge is compensated by electrophilic cations capable of accepting electron density, such as alkali cations, the material acts as a Lewis acid. The advantage of zeolites holding either of the two types of sites, is that they become catalytically active. 1.2. Lignocellulosic Biomass for the Production of Aromatics Environmental and political concerns initiated research on the use of sustainable alternatives to the current fossil-based technologies for the production of chemicals, fuels and energy. Biomass-based resources, solar and wind power are examples of such sustainable resources. 6–11 The use of biomass for the production of chemicals is seen as a promising route for the replacement of current fossil-based resources. Biomass consists of ca. 40-80, 15-30 and 10-25 % percent of cellulose, hemicellulose and lignin, respectively. The exact distribution varies from source to source. 6,12 Cellulose is a crystalline polymer consisting of glucose monomers and provides structural rigidity to the plant cell walls. Hemicellulose is an amorphous polymer consisting of a wide variety of pentoses (xylose, arabinose) and hexoses (mannose, glucose) holding the cellulose fibers in place.
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