Conversão enzimática de resíduos derivados do processamento do pinus elliotti para obtenção de bioetanol

Abstract

Polymerized sugars containing lignocellulosic materials, such as cellulose and hemicellulose, which can be hydrolyzed to facilitate their fermentation by yeast and production of ethanol. This study aimed to the production of second generation bioethanol from derivatives of Pinus elliotti previously treated by acid for removal of hemicellulose, basic treatment to remove the lignin, with or without heating at normal pressure or 1.2atm, followed by enzymatic conversion. Two experiments were conducted for comparison purposes, Δ1 and Δ2. The delignified biomass was subjected to enzymatic hydrolysis using various commercial enzymes: cellulase, β -glucosidase, xylanase and hemicellulase. After conversion, the hydrolyzate was fermented using Saccharomyces cerevisiae, distilled, and the ethanol concentration was determined by cryoscopic method. For Δ1 the removal of hemicellulose by extracting was 29%, while the average of Δ2 was 17%. For Δ1 the lignin removal showed lower when compared to Δ2. The experiment Δ1 solubilized about 50% of the biomass, and for the experiment Δ2 an average yield of 41%. The best ethanol yields were obtained in experiment Δ1, wherein the biomass is subjected to heating, with an average yield of 2.7 g/L and 1.7g/L to the experiment Δ2. In terms of biomass conversion to ethanol, the best results were obtained in experiment Δ1, with an average of 0.20% conversion. As for the Δ2 experiment , the conversion averaged 0.15 % .