Productive and parasitic pathways in dilute acid-catalyzed hydrolysis of cellulose

Abstract

Cellulose hydrolysis experiments were conducted in a percolating reactor at 34.5 MPa. A glucose yield of 71% of the theorical maximum was obtained at 215°C with 0.05% by weigth of sulfuric acid in percolating solution. The classical model of glucose formation from cellulose followed by secondary sugar degradation did not describe the reaction chemistry under these conditions. A parasitic pathway which leads to the formation of nonhydrolysable oligomer was discovered in the absence of acid. In the presence of acid, kinetic modeling of the measured, temperature-dependent rates of glucose evolution indictaes that an acid-catalized parasitic pathway operates in competition with the glucose production pathway. No chemical change were detecte in the solid phase during the course of reaction