Effects of sonication on the reactivity of chitin toward its heterogeneous deacetylation

Abstract

Samples of chitin were submitted to heterogeneous deacetylation in aqueous sodium hydroxide (40%) during 6 hours at 115 - 2°C. These reactions were carried out with crude chitin and also with samples previously submitted to ultrasound treatment in aqueous suspension for different periods of time. The previous sonication of chitin strongly enhanced its reactivity toward the deacetylation reaction but only slightly favored the depolymerization process. Adding sodium borohydride to the reaction medium reduced the occurrence of depolymerization when untreated chitin was employed but it had no such effect if sonicated chitin was reacted.