Tratamento de resíduo da Agave sisalana para a produção do bioetanol

Abstract

The production of biofuels from renewable, sustainable and economically viable sources has stood out since the last decades due to environmental problems, finite reserve of fossil fuels and environmental pollution. This research aimed to evaluate the technical viability of bioethanol production from Agave sisalana residues. The residues of this culture are sources of polysaccharides and sugars when pre-treated by the hydrolysis technique. In order to obtain fermentable sugars, this biomass was pre-treated by acid hydrolysis. The experimental analysis program, ESTATISTICA 7.0 was used to analyze the favorable experimental design for acid hydrolysis of solid waste, and Analysis of Variance (ANOVA), for the study of the response surface. The results of the pre-treatment and hydrolysis were considered significant in terms of the amount of fermentable sugars and total sugars after hydrolysis, with measures of 23g / L and 35g / L, respectively. The acid concentration is a significant variable to improve the efficiency of the response variables that are reducing sugars through experimental planning, thus contributing to the optimization of a process that allows the increase in reducing sugars and favored the efficiency of fermentation by 50% compared to non-hydrolyzed raw material. The analyzes of physico-chemical characterization of bagasse and liquid residue were carried out by dry basis, moisture, ash, calorific value, thermogravimetric analysis, sieving, and analysis of reducing and total sugars by DNS, analysis of volatile soluble solids, XRD and pH. Hydrolysis increased the amount of fermentable sugars with a percentage of bagasse conversion to 50% sugars. The alcoholic fermentation process took place with the yeast Saccharomyces cerevisiae, with a yield of 88% in relation to the conversion of sugars into bioethanol.