Producción y análisis de bioetanol fabricado a partir de la fermentación de los residuos provenientes de la explosión de vapor de las hojas maduras y cogollos de la caña de azúcar, previamente hidrolizados con enzima

Abstract

Sugar cane is a monoculture that occurs in Ecuador on a large scale and when used in the sugar industry, it generates residues such as buds and leaves, which are generally considered as waste. However, these agro-industrial wastes can be converted into feedstock for biofuel production processes. This is the case with the generation of bioethanol. In this work, in order to take advantage of the residues, we first started from the pretreatment of the biomass through the process of steam explosion, the pretreatment was carried out at temperatures of 150, 155, 165 and 180 °C for 1 s and 10 min of residence time. This process produces a residual liquid rich in degradation products of cellulose and hemicellulose. These products were hydrolyzed for 72 h in a reactor, at two temperatures (45 and 50 °C) and agitation speed (50 and 200 rpm), in the presence of cellulase and B-glucosidase, (enzymes that break the bonds between the monosaccharides to obtain sugars capable of being fermented in a bioreactor at different temperature conditions (25-35 °C)). The resulting sugars were quantified using the Dubois method (phenol-sulfuric). For the best condition evaluated, an increase of 71. 7 g/L of sugars was obtained, with respect to the initial concentration of hydrolysis (50 °C, 200 rpm, enzyme Cellic Ctec 2) which used the vapour explosion liquids at 180 °C for 10 minutes, with three recirculations. The sugar-rich liquid was then used to produce ethanol, which was quantified using the distillation method and the pycnometer method, obtaining a concentration of 87 g/L.