Experimental Ethanol Production with Acid-enzyme Hydrolysis from Straw Paper Pulp

This paper describes a new experimental process of ethanol production from straw paper pulp hydrolyzed with acid and enzyme.The influences of reaction time,temperature,substrate concentration,catalyst content on the diluted acid hydrolysis and the cellulose enzyme hydrolysis were researched.The change of sugar content in the hydrolysate was analyzed.The results showed that the optimized conditions of dilute sulfuric acid hydrolysis are temperature 180 ℃,the rate of solid to liquid 20∶1,mass of sulfuric acid 0.024 g H2SO4 /g solvent,and reaction time 2 h,the yield of reducing sugar was 28.9%.Optimized conditions of enzymatic hydrolysis are temperature 55 ℃,enzyme concentration 80 U/g material,substrate concentration 0.01 g/mL,and hydrolysis time 30 h,the yield of reducing sugar was 67.1%;The yield of total reducing sugar was 62.6% with acid-enzyme hydrolysis method;After the hydrolysate was fermented,the ethanol concentration was 26.6 g/L,ethanol yielding rate was 49%,theoretical conversion rate of ethanol was 95.0% and reached 0.28 g/g ethanol/straw paper pulp.