Transformation of aqueous solutions of glucose over the Pt/C catalyst

Abstract

The transformations of glucose over the Pt/C catalyst in a flow reactor in the temperature range 140–200°C at a pressure of 5.0 MPa have been studied. The main routes of glucose conversion in an aqueous phase in the presence of hydrogen, helium, or air have been considered. A product formation scheme depending on the reaction parameters has been proposed. At 140°C, glucose hydrogenation into sorbitol occurs with a selectivity of 77%. In an oxidizing atmosphere, glucose transforms into gluconic acid (with 73% selectivity at 140°C); here, the formation of sorbitol and mannitol (with a selectivity of 5–7% at 180–200°C) is also possible. Glucose transformation by-products, such as C3–C5 polyatomic alcohols, ketones, acids, and furfural derivatives, have been identified. The degree of glucose reforming in the aqueous solution with the formation of the gaseous products H2 and CO2 is no higher than 10% at 200°C.