Bio-flocculation Detoxification Treatment with Acid Hydrolyzate of Corn Straw for Ethanol Production

Lignocelluloses materials were selected for ethanol production, but certain problems occurred, such as the hydrolysis and detoxification process. A biological flocculation technology was to apply for the detoxification of acid hydrolyzate of lignocelluloses materials. Meanwhile chitosan was confirmed as the best biological flocculant which showed good detoxification effect. In order to reach the optimal detoxification effect, the Box-Behnken experimental design was carried out. The most important parameters affecting the efficiency of detoxification are dosage, temperature, reaction time, and pH of the solution. The optimal parameters were: flocculant dosage of 0.25 g L, pH of 4, reaction time of 10 minutes, and reaction temperature of 41°C. The calculated detoxification rate was 78.2 %. Through three confirmation experiments, the practical detoxification rate was 78 %, which was close to the theoretical prediction. This model had good reliability and reproducibility.