Heterogeneous N-deacetylation of squid chitin in alkaline solution

Chitin was extracted from squid pens and its heterogeneous alkaline deacetylation was performed using various conditions. The reaction followed the pseudo-first-order kinetics during an initial period. The influences of alkaline concentration, temperature, time and chitin to solution ratio on the N-deacetylation were investigated. The degree of deacetylation (DD) increased mainly with increasing temperature, NaOH concentration and time. The effect of the chitin to solution ratio was insignificant. In the temperature range of 40–100 °C, the apparent rate constant and the activation energy of the reaction ranged from 1.0×10−3 to 2.4×10−2 min−1 and from 5.4 to 11.9 kcal/mol, respectively. The linear regression analysis was performed to predict the optimum conditions for 90% DD chitosan product.