Biomass derived bifunctional catalyst for the conversion of cassava dreg into sorbitol

A biomass derived bifunctional catalyst (Ru/CCD-SO 3 H) was used for one-pot conversion of cassava dreg and cassava starch into sorbitol . The cassava dreg is mainly composed of residual cassava starch and holocellulose. The highest sorbitol yield of 11.43 % was achieved using cassava dreg as reactant. A synergistic catalytic effect of acid and metal sites of Ru/CCD-SO 3 H on cassava starch conversion to sorbitol was observed. The maximum sorbitol yield reached 82.51 % using cassava starch as reactant. A kinetic model of cassava starch degradation was performed. The reaction rate constants of cassava starch degradation, glucose conversion and sorbitol generation improved with enhancing temperature. The activation energy of cassava starch hydrolysis is larger than that of glucose hydrogenation, indicating the cassava starch hydrolysis is rate-determining step of cassava starch conversion into sorbitol. This work not only realizes the comprehensive utilization of cassava dreg, but also provides useful guidance for developing kinetic model of polysaccharide conversion.