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The use of waste cellulosic material to produce fuel alcohol is one of the effective ways to solve the energy crisis. Cellulose ethanol production, the raw materials must be pretreated, but some of the byproducts generated after pretreatment will inhibit the enzymatic hydrolysis or fermentation. In this paper, the most widely used steam explosion pretreatment method for the study, and examine the impact on the fermentation of corn stover steam explosion pretreatment after several organic and inorganic. According to the results, the researchers remove the role of the laboratory screening of detoxification of the strains FLZ10 of these substances, and to do further study the biological detoxification of the strains. First, the the AFM observed pretreatment before and after of corn stover surface structure changes that steam explosion pretreatment and acid explosion pretreatment technology can play a role to break the compact cellulosic feedstocks. According to the results of the the lotion and mash analysis of steam exploded straw feedstock, pretreatment and fermentation byproducts of ethanol production. The results showed that the inorganic ions Mg 2 and Fe 2 significantly inhibited ethanol production, ethanol production decreased by 34.43% and 11.48%, respectively; ethanol production with salt increasing amount of reduced; organics formic ≤ 2g / L concentration range does not exhibit significant inhibition but slightly promoted effect; Titanium promoting effect on fermentation performance at a low concentration, the concentration of 15g / L, significantly suppressed significant role in promoting ethanol production, ethanol production reduced by 91.69%, and with the increase in the concentration of acetic acid suppression enhanced; furfural concentration ≤ 1g / L; produce inhibition of 5-HMF concentration ≥ 2.0g / L of ethanol production , ethanol production reduced by 54.03%. Secondly, a byproduct inhibition for the removal of based research FLZ10, agents of these substances. The results showed that the inorganic ions, FLZ10 2 on Ca the Mg 2 Al 3 the Fe 2 have removal, the culture 48h removal rates were 70%, 50%, 90%, 80%. Organic compounds, 35 ℃ with glucose as the carbon source, FLZ10 acetic acid, propionic acid, butyric acid 96h removal rates were 24.20%, 30.92%, 27.73%. 35 ℃ with glucose as the carbon source, FLZ10 furfural and 5-HMF removal efficiency of 56.52%, 69.21. The actual fermentation FLZ10 biological detoxification effect is obvious, available washing detoxification same effect, and auxiliary washed detoxification up to 50g / L ethanol final yield. Again, in order to reduce the cost of biological detoxification on FLZ10 inoculant medium optimized. According to the CB enzyme activity and FPA enzyme activity measured several agents and its straw lotion inhibitor removal, showed that 50 ℃, 40 ℃ is more conducive to the role of the enzyme, while 40 ℃ the 50 ℃ more conducive FLZ10 to pair fermentation inhibitor metabolism. To do with reference to the original medium, the enzymatic activity of CB agents optimize test medium all-bran medium and FPA enzyme activity were the highest; SBR and EGSB effluent medium removal of organic acids is the best; wholly bran culture removal effect of the group of formic acid, furfural and 5-HMF. But several medium at 40 ℃, the effect of differences in the removal of the inhibitor is not very big, comprehensive evaluation to determine cheap corn stalk powder instead of crystalline cellulose production inocula medium. Finally, we discuss the contribution of several trace elements add nutrients to the fermentation. Experimental results show that single factor analysis and orthogonal analysis, trace elements of nutrients can promote fermentation, ethanol production with the order of pantothenic acid gt nutrients; cobalt gt; VB1 gt; zinc gt; manganese gt; nickel gt ; inositol. The amount of seven kinds of substances to be elected as nickel chloride hexahydrate 50 μm / L manganese chloride 25mg / L, zinc sulfate heptahydrate 6mg / L cobalt chloride octahydrate 30μm / L, and inositol 150mg / L , pantothenic 10ml / L, VB1150mg / L,.
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