Evaluation of industrial processes to obtain chitin and chitosan

Abstract

In this research, the operational conditions for the industrial chemical processes to obtain chitin and chitosan are analyzed. The obtention of chitosan was performed using crab wastes from the industry using the exoskeleton of blue crab (Callinectes sapidus). The four main steps for obtaining chitosan were: deproteinization with NaOH 10%, demineralization using two acids (hydrochloric acid and phosphoric acid) of two different concentrations with reaction time variations to determine the more acceptable acid for the remotion of minerals, decoloration using sunlight irradiation and as final step thermoalcaline hydrolysis of chitin with 30% NaOH. The chitosan obtained was characterized by FTIR where the bands of the functional groups characteristics for chitosan were observed, the amine group band at 1,621 and 1,650 cm-1, the acetamide group (amide I). Chitosan with degree of deacetylation berween 82.52 and 95.01 % was obtained calculated by Fourier Infrared Transformed. Additionally, percentage of ashes and humidity were measured. Industrial chitosan was obtained with high viscosity, high molecular mass and high degree of deacetylation with this treatment.