Nb/HUSY as a highly active catalyst for the direct transformation of fructose to methyl lactate.

One-pot conversion of biomass-based carbohydrates to methyl lactate (MLA), a versatile platform chemical for the production of food additives as well as the starting material of pharmaceutical industry, is an attractive green process. In this study, the Nb/HUSY catalysts with highly catalytic performance are successfully synthesized and used for the production of MLA from fructose. Remarkably, when using 2%Nb/HUSY as catalyst, the highest MLA yield of 56.1% is obtained with complete conversion of fructose under optimal conditions (140 °C for 6 h). The introduction of niobium into HUSY enhances the Lewis acid properties, which facilitates the stepwise process, involving the retro-aldol condensation and dehydration reactions. The as-prepared catalysts have shown promising potential for conversion of fructose to MLA and effectively inhibited the formation of by-products. More importantly, the catalyst exhibits superior stability and could be reused for at least four cycles. Image 1 • A controllable transformation of fructose into green methyl lactate is demonstrated. • The combination of strong Lewis and weak Brønsted acid enhanced catalytic activity. • The Lewis/Brønsted ratios of the Nb/HUSY catalysts can be easily tuned. • The as-prepared catalysts afford superior catalytic performance. [ABSTRACT FROM AUTHOR]