Apparent activation energy of hydrolysis of some cellulosic materials

Apparent activation energies for heterogeneous acid hydrolysis of four samples of cellulose which differed in crystallinity were calculated separately for the amorphous and crystalline regions, from data obtained under drastic hydrolytic conditions. Some approximate activation energies were also calculated for hydrolysis of the amorphous fraction of cotton and a viscose rayon, using data obtained with a range of dilute acid concentrations. These values are discussed in relation to hydrolytic conditions. The relations between the hydrolysis rate, the acidity function (H0), and the hydrogen‐ion concentration, as well as the values of activation entropy were examined for evidence with respect to reaction mechanism. Data from the literature were used to show that the activation energy probably is temperature dependent.