The kinetics of decarboxylation of uronic acids, polysaccharides, and oxycelluloses

Abstract

Measurements of the rate of carbon dioxide evolution from sulphuric acid solutions of galacturonic acid have revealed that it follows first-order kinetics, but some carbon dioxide is also formed in a side reaction at a constant rate. Glucuronolactone, polyglucuronic acid, and oxycelluloses decarboxylate in essentially homogeneous sulphuric acid solutions according to a two-step reaction scheme, both steps being kinetically first order. This main reaction is accompanied by side reactions in which carbon dioxide is evolved at an approximately constant rate. Mathematical expressions have been derived and applied to compute the constants of the rate equation for the decarboxylation of materials containing uronic acid.