SO2蒸汽预处理对黑松制取生物乙醇的影响

以加拿大不列颠哥伦比亚省甲虫致死黑松为原料，通过SO2催化蒸汽爆破方式对其进行预处理，并对预处理后的原料进行酶水解和乙醇发酵研究，以考察预处理方式结合酶水解对黑松制取乙醇的影响。结果表明，较低的SO2吸收率和原料含水率（干基）影响了预处理效果；水洗对预处理后原料的酶水解效率没有显著的影响；当水解底物质量浓度由20 mg/mL增加到150 mg/mL时，水解率均在42%左右，底物质量浓度的增加纤维素的水解率没有受到显著影响。从发酵结果看，黑松经汽爆预处理后，不进行水洗处理更有利于后续发酵。分步糖化发酵乙醇得率可以达最大乙醇得率的66%，而同步糖化水乙醇得率为55%。由此可见，低浓度SO2催化汽爆预处理低湿度黑松不能得到较好的预处理效果，需进一步优化。

Bioethanol production from lodgepole pine by SO2-catalyzed steam explosion

In this study, the beetle-killed lodgepole pine from the Province of British Columbia, Canada was used as the raw material for steam explosion to investigate the effects of the process of bioethanol production with enzymatic hydrolysis and subsequent fermentation. The results indicated that the lower SO2 absorption and the lower moisture content (dry basis) of the raw material affected the efficiency of the steam explosion; Water-washing on the pretreated substrate had no significantly influence on the enzymatic hydrolysis. The cellulose-glucose conversions were kept as 42% without significant variation while the substrate consistency increased from 20 mg/mL to 150 mg/mL, which implied that increasing the substrate consistency had no significant influence on enzymatic hydrolysis. Additionally, the fermentation results showed that the exploded substrate without water-washing was beneficial for subsequent fermentation. The ethanol yield in SHF and SSF only could reach 66% and 55%, respectively, compared with the theoretical ethanol yield. As a result, applying SO2-catalyzed steam explosion for enzymatic hydrolysis with lower SO2 absorption and lower moisture content of raw material is not very efficient and needs further optimization for the lodgepole pine.