title: Competitive Adsorption of Substrate and Solvent in Sn-Beta Zeolite During Sugar Isomerization.
abstract: The isomerization of 1,3-dihydroxyactone and d-glucose over Sn-Beta zeolite was investigated by in situ13C NMR spectroscopy. The conversion rate at room temperature is higher when the zeolite is dehydrated before exposure to the aqueous sugar solution. Mass transfer limitations in the zeolite micropores were excluded by comparing Sn-Beta samples with different crystal sizes. Periodic density functional theory (DFT) calculations show that sugar and water molecules compete for adsorption on the active framework Sn centers. Careful solvent selection may thus increase the rate of sugar isomerization. Consistent with this prediction, batch catalytic experiments show that the use of a co-solvent, such as tetrahydrofuran, that strongly interacts with the Sn centers suppresses glucose isomerization. On the other hand, the use of ethanol as cosolvent results in significantly higher isomerization activity in comparison with pure water because of decreased competition with glucose adsorption on zeolitic Sn sites.
authors: Inorganic Materials Chemistry Group, Schuit Institute of Catalysis, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands.
authors: William N P
authors: WN
authors: van der Graaff
authors: Inorganic Materials Chemistry Group, Schuit Institute of Catalysis, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands.
authors: Christiaan H L
authors: CH
authors: Tempelman
authors: Inorganic Materials Chemistry Group, Schuit Institute of Catalysis, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands.
authors: Guanna
authors: G
authors: Li
authors: Inorganic Materials Chemistry Group, Schuit Institute of Catalysis, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands.
authors: Brahim
authors: B
authors: Mezari
authors: Inorganic Materials Chemistry Group, Schuit Institute of Catalysis, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands.
authors: Nikolay
authors: N
authors: Kosinov
authors: Inorganic Materials Chemistry Group, Schuit Institute of Catalysis, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands.|Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands.|Theoretical Chemistry group, Laboratory for Solution Chemistry of Advanced Materials and Technologies, ITMO University, St. Petersburg, Russia.
authors: Evgeny A
authors: 0000-0001-9242-9901
authors: EA
authors: Pidko
authors: Inorganic Materials Chemistry Group, Schuit Institute of Catalysis, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands.
authors: Emiel J M
authors: EJ
authors: Hensen
mesh_terms: D000327:Adsorption; D002384:Catalysis; D004098:Dihydroxyacetone / Q000737:chemistry*; D005947:Glucose / Q000737:chemistry*; D007536:Isomerism; D008958:Models, Molecular; D008968:Molecular Conformation; D011789:Quantum Theory; D012997:Solvents / Q000737:chemistry*; D014001:Tin / Q000737:chemistry*; D014867:Water / Q000737:chemistry; D017641:Zeolites / Q000737:chemistry*
chemical_list: D012997:Solvents; D014867:Water; D017641:Zeolites; D014001:Tin; D005947:Glucose; D004098:Dihydroxyacetone
keywords: Lewis acids; Sn-beta; carbohydrates; competitive adsorption; solvent replacement