稀硫酸预浸渍对玉米秸秆蒸汽爆破预处理的影响

为提高纤维素乙醇生产中传统蒸汽爆破预处理的效果，以稀硫酸（质量浓度0．2％）对玉米秸秆进行预浸渍，再于190～210℃对其进行汽爆预处理。结果表明：稀硫酸预浸渍有利于增强汽爆过程中半纤维素的水解程度，并能有效减少乙酸的生成；200℃预处理玉米秸秆经过96h同步糖化发酵，最终乙醇浓度为22．5g·L-1，为理论值的76％，较预浸渍前（19．0g·L-1）明显提高。稀硫酸预浸渍能够增强玉米秸秆的汽爆预处理效果。

The Effect of Dilute Sulfuric Acid Impregnation on Steam Explosion Pretreatment of Corn Stover

To improve the effect ot traditional steam explosion pretreatment in lignocellulosic ethanol pro- duction,the corn stover was impregnated with 0.2% sulfuric acid before steam explosion pretreatment at 190- 210 ℃. The results showed that dilute sulfuric acid impregnation was beneficial to enhance the hydrolysis of hemicellulose and decreased the generation of acetic acid. In the following simultaneous saceharification and fer- mentation （SSF） ,a final ethanol concentration of 22.5 g·L-1 was obtained,corresponding to 76 % of the theo- retical maximum ethanol yield,which was obviously higher than that obtained without dilute sulfuric acid im- pregnation（19.0 g ·L-1）. It is proved that dilute sulfuric acid impregnation can improve the effect of steam ex- plosion pretreatment of corn stover.