Estudio de la influencia del tiempo en la reacción de hidrólisis ácida para la obtención de glucosa a partir de la cáscara de cacao

Abstract

The main objective of the present project was to determine the influence of the reaction time in the acid hydrolysis stage of the cocoa shell, which it was started by sampling the cocoa cobs in the Putucay parish located near the La Troncal canton. Subsequently, the samples were pretreated, by drying and size reduction and then determining their chemical composition, where results of 21,57 % extractable, 27,59 % lignin, 21,65 % cellulose, and 13,58 % hemicellulose were obtained. Then, the acid hydrolysis reaction was performed under conditions of 4% v/v sulfuric acid, at 100°C in a discontinuous reactor of perfect mixture, with variable reaction time in the range of 0 to 70 minutes. The hydrolyzed liquid was analyzed by High-Performance Liquid Chromatography (HPLC) resulting in a maximum glucose concentration of 4,40 g / L for 30 minutes. On the other hand, by means of the linear regression integration method, the kinetics of the hydrolysis reaction was determined to be of second order (n = 2) with a velocity constant k = 0,0032 g -1 min-1 . Finally, the solid residue of the hydrolysis reaction was chemically characterized for times within the kinetic region, reaching a lignin content of 49,54% and 49,96% holocellulose.