Utilização dos resíduos sólidos da indústria cacaueira para produção de etanol

• Ano de defesa: 2018
• Autor(a) principal: Silva, Rhuany de Oliveira
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Espírito Santo; BR; Mestrado em Engenharia Química; UFES; Programa de Pós-Graduação em Engenharia Química
• Palavras-chave em Português: Biomass; Cocoa; Bioethanol; Acid hydrolysis; Fermentation; Bioetanol; Hidrólise ácida; Fermentação; Biomassa; Cacau; Álcool; Hidrólise; Engenharia Química; 66.0
• Link de acesso: http://repositorio.ufes.br/handle/10/7820

The cocoa industry generates a considerable amount of solid waste consisting mostly of fruit peel, which is mainly composed of cellulose, hemicellulose and lignin. In order for the cellulose to be accessible and can be converted into sugar, then into ethanol, a pre-treatment of the raw material is necessary, which involves an association of physical and chemical methods. This work aims to evaluate the viability of using cocoa peel as raw material for production of bioethanol. By determining the chemical composition of the peel in natura and pre-treated, by studying operational conditions of acid hydrolysis with different diluted H2SO4 and the alcoholic fermentation from the hydrolysates of the pretreated peel. In order to characterize the material, were analyzed moisture, ash, hemicellulose, cellulose, extractives and lignin. For the purpose to perform the acid hydrolysis using pre-treated cocoa peel with hydrogen peroxide (H2O2), an experimental planning of the factorial type (3²) with three central points was used, varying the acid concentration (0.20% m/v, 0.34% m/v e 0.48% m/v) and the hydrolysis time (60, 90 e 120 min.). After the hydrolysis, fermentation tests were carried out, in which the cell growth kinetics and the ethanol concentration were monitored. The experiments to characterize in natura and pre-treated peel, presented a considerable percentage of cellulose being 32.46% and 75.48%, respectively, results that indicate the efficiency of the chemical pretreatment as promisor to ethanol production. The best hydrolysis condition was obtained in 90 minutes and 0.34% w/v acid, in which approximately 13 g/L of ART was obtained. From the results of the alcoholic fermentation with supplementation of 10 g/L of glucose in the hydrolysate, it was obtained around 19% v/v (°GL).