Lewis acidity of titania catalyst in water

Abstract

H₃PO₄-treated titania was found to be effective solid acid catalyst for converting 1,3-dihydroxyacetone (triose sugar) into lactic acid and xylose into furfural in water.  FT-IR measurement using pyridine as a basic molecular probe revealed that H₃PO₄-treated titania has not Brønsted acid sites but water-tolerant Lewis acid sites on the surface. High catalytic performance of titania catalyst is therefore attributed to water tolerant Lewis acid sites that proceed effectively on  dehydration and hydride shift reactions.