Process optimization of ethanol production from steam exploded corn stalk by simultaneous saccharification and fermentation

The process of cellulose ethanol production by simultaneous saccharification and fermentation (SSF) was studied in this paper, and the optimum conditions of the process were found by single-factor experiment and orthogonal test. The conditions were as follows: reaction temperature 37℃, pH value 4.8, loading of substrate 15%, loading of 0.15% Tween-20 as surfactant, loading of cellulose 30 U/g, the yeast active by 2% glucose, yeast inoculums 5‰, and the medium compositions were KH2PO4 2.5 g/L, (NH4)2SO4 2.0 g/L, MgSO4·7H2O 0.15 g/L, CaCl2 0.35 g/L. Under the optimum conditions, the volume of ethanol is 2.85(v/v), then the ethanol yield can reach to 88.12% of the theoretic results after 60 h.