Kinetic modelling of hydrolysis of β (1 → 4) glycosidic bonds in cellobiose over alkali-exchanged X zeolites

Abstract

Kinetic experiments for the hydrolysis of cellobiose were performed in the presence of synthetic zeolite catalysts. The sodium, lithium and potassium forms of type X zeolites were employed in concentrations in the range 2.8 × 10 −3 to 6.3 × 10 −3 unit cells per liter, at temperatures in the range 90–110°C. The reaction products were divided into four classes and a mathematical model was postulated to describe the time evolution of these products. The kinetic parameters involved in the model were estimated using a quasilinearization technique. It was found that the results predicted by the model are in satisfactory agreement with experimental data. Adsorption of organic species on the surface of the zeolite as well as the capacity of cellobiose to diffuse in the pores of the zeolite are discussed.