Optimization Based on Kinetic of Dilute-Acid Hydrolysis of Sugar Cane Bagasse in Bio-Ethanol Production

摘要

Hydrolysis is an important step in the degradation of holo-cellulose to monohydrates for bio-ethanol production. Ethanol from sugarcane bagasse is very prospective, because the cellulose content is high (40.27%) and its amount is very abundant. The purpose of this study was to study the optimization of hydrolysis conditions of sugarcane bagasse with dilute sulfuric acid catalyst based on reaction kinetics. The hydrolysis of sugarcane bagasse was carried out at various sulfuric acid concentrations (0.3, 0.4, 0.5, 0.6 mol/L), temperatures (70, 80, 90, 100 °C), and times (15, 30, 45, 60, 75 min). The hydrolysis kinetics are solved by a homogeneous reaction approach accompanied by sugar degradation. The results showed that the catalyst concentrations, temperatures, and times greatly influenced the hydrolysis of sugarcane bagasse. The higher the temperature and catalyst concentration, the higher the hydrolysis reaction and sugar degradation will be. As a result, the longer the hydrolysis, the lower the sugar concentration will be. The degradation of sugar began to be seen at 90 °Cand the catalyst concentration was 0.5 mol/L. The simulation results showed that the order of hydrolysis reaction is 1 and sugar degradation is 2. The correlation between the activation energy and the catalyst concentration can be expressed by the equation In (E_(hyd)) = 11.593 - 0.0329C_(ca)t and In (E_(deg)) = 10.869 - 0.0785C_(ca)t for hydrolysis and sugar degradation, respectively. The optimum sugar concentration obtained was 0.002 mol/L at 100 °C, catalyst concentration 0.567 mol/L and 40 min.