title: Strategies for Enhancing the Catalytic Performance of Metal-Organic Frameworks in the Fixation of CO2into Cyclic Carbonates.
abstract: Metal-organic frameworks (MOFs) with accessible Lewis acid sites are finding increasing application in the field of heterogeneous catalysis. However, the structural instability of MOFs when they are exposed to high temperature and/or high pressure often limits their applicability. In this study, two strategies were applied to achieve a MOF catalyst with high stability, activity and selectivity in the reaction of CO2with styrene oxide to produce styrene carbonate. In the first approach, a MOF with linkers with high connectivity as MIL-100(Cr) was studied, leading to promising activity and recyclability in consecutive catalytic runs without loss of activity. In the second strategy, a MOF with linkers with lower connectivity but with encapsulated Keggin phosphotungstic acid (MIL-101(Cr)[PTA]) was prepared. However, the activity of this catalyst decreased upon reuse as a consequence of deterioration of the MOF. Further investigations were dedicated to the enhancement of the catalytic performance of MIL-100 and included the variation of the metal centre as well as the type and loading of organic salt acting as nucleophile source. This allowed tuning the nature of the organic halide to the specific porous structure of MIL-100(Cr) to prevent diffusion limitations. The best catalytic performance was obtained for MIL-100(Cr) in combination with EMIMBr ionic liquid, which gave very high styrene carbonate yield (94 %) with complete selectivity after 18 h of reaction at mild temperature (60 °C).
authors.affiliation: Chemical Engineering Group, Engineering and Technology Institute Groningen, ENTEG, University of Groningen, Nijenborgh 4, 9747, AG, Groningen, The Netherlands.|Faculty of Science, Babol Noshirvani University of Technology, Babol, Iran.|Centre for Surface Chemistry and Catalysis, University of Leuven, KU Leuven, Celestijnenlaan 200F, 3001, Heverlee, Belgium.
authors.forename: Masoumeh
authors.initials: M
authors.lastname: Taherimehr
authors.affiliation: Centre for Surface Chemistry and Catalysis, University of Leuven, KU Leuven, Celestijnenlaan 200F, 3001, Heverlee, Belgium.
authors.forename: Ben
authors.initials: B
authors.lastname: Van de Voorde
authors.affiliation: Centre for Surface Chemistry and Catalysis, University of Leuven, KU Leuven, Celestijnenlaan 200F, 3001, Heverlee, Belgium.
authors.forename: Lik H
authors.initials: LH
authors.lastname: Wee
authors.affiliation: Centre for Surface Chemistry and Catalysis, University of Leuven, KU Leuven, Celestijnenlaan 200F, 3001, Heverlee, Belgium.
authors.forename: Johan A
authors.initials: JA
authors.lastname: Martens
authors.affiliation: Centre for Surface Chemistry and Catalysis, University of Leuven, KU Leuven, Celestijnenlaan 200F, 3001, Heverlee, Belgium.
authors.forename: Dirk E
authors.initials: DE
authors.lastname: De Vos
authors.affiliation: Chemical Engineering Group, Engineering and Technology Institute Groningen, ENTEG, University of Groningen, Nijenborgh 4, 9747, AG, Groningen, The Netherlands.|Centre for Surface Chemistry and Catalysis, University of Leuven, KU Leuven, Celestijnenlaan 200F, 3001, Heverlee, Belgium.
authors.forename: Paolo P
authors.identifier: 0000-0003-3608-6400
authors.initials: PP
authors.lastname: Pescarmona
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry*; D002254:Carbonates / Q000737:chemistry*; D002384:Catalysis; D002857:Chromium / Q000737:chemistry; D006219:Halogens / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D009942:Organometallic Compounds / Q000737:chemistry*; D020058:Styrene / Q000737:chemistry
chemical_list: D002254:Carbonates; D006219:Halogens; D009942:Organometallic Compounds; D002857:Chromium; D002245:Carbon Dioxide; D020058:Styrene
keywords: carbon dioxide; cyclic carbonate; heterogeneous catalysis; metal-organic frameworks; sustainable chemistry