Hydrolysis of dextrin in the presence of 12‐tungstosilicic acid

摘要

AbstractHydrolysis of dextrin in the presence of 12‐Tungstosilicic acid was investigated, and the acid was found to show an approximately two times higher catalytic activity than did hydrochloric acid. From the comparison of degree of dissociation of 12‐tungstosilicic acid with that of hydrochloric acid, examination of the influence of the ionic strength on the reaction rates, analysis of the reaction products, and evaluation of activation parameters of the reaction, it was assumed in conclusion that the higher catalytic activity of 12‐tungstosilicic acid resulted from a “concentration effect” due to the complex formation of the heteropolyanions with dextrin molecules, and from the effect of its higher ionic strength, but not from the effect of direct participation of the heteropolyanion to the elementary reactio