The telescopic conversion of glucose to fructose and then 5-hydroxymethylfurfural (5-HMF), the latter a potential, bio-derived platform chemical feedstock, has been explored over a family of bifunctional sulfated zirconia catalysts possessing tuneable acid-base properties. Characterisation by acid-base titration, XPS, XRD and Raman reveal that submonolayer SO4 coverages offer the ideal balance of basic and Lewis-Brønsted acid sites required to respectively isomerise glucose to fructose, and subsequently dehydrate fructose to 5-HMF. A constant acid site normalised turnover frequency is observed for fructose dehydration to 5-HMF, confirming a common Brønsted acid site is responsible for this transformation. This journal is
Bibliographical noteFunding: EPSRC (EP/K000616/1); MEL Chemicals for the supply of Zr(OH) 4; Royal Society for the award of an Industry Fellowship; EPSRC for a Leadership Fellowship (EP/G007594/2); Spanish Ministry of Economy and Competitiveness (project CTQ2011-28216-C02-01).
Electronic Supplementary Information: Porosimetry, tables of
product data from catalytic reactions. See DOI: 10.1039/c3cy00409k