秸秆碱预处理液脱毒及其在丁醇发酵中的应用

Detoxification process of alkali-pretreated solution of corn stover and its application in butanol fermentation

秸秆的碱预处理液可造成严重的环境污染。该研究基于源头控制的理念,对碱预处理液进行脱毒工艺研究并回收进行丁醇发酵研究。通过加酸去除碱预处理液中的木质素,用活性炭将去除木质素的预处理液脱毒并用于水解和发酵过程。优化获得沉淀碱溶性木质素的最佳pH 3.8;不同加量活性炭脱毒后的碱预处理液对秸秆水解的影响不明显,然而活性炭的添加量对丁醇发酵影响较大,当活性炭添加量为15 g/L时,发酵72 h达到最高丁醇质量浓度10.2 g/L。该秸秆碱预处理液脱毒工艺对利用秸秆进行无废生产生物燃料有一定参考价值。

Alkali-pretreated solution of corn stover is one of the main waste water that causes environmental pollution.To reduce the source of pollution,detoxification process of pretreatment solution was developed and applied in butanol fermentation.The lignin in the alkaline pretreatment solution was precipitated and removed by adding sulfuric acid,then the lignin-removed pretreatment solution was detoxified with activated carbon and reused in hydrolysis and fermentation.The optimum pH for precipitating alkali-soluble lignin was 3.8.Alkali pretreatment solution detoxified with different amount of activated carbon had no obvious effect on corn stover hydrolysis,whereas the addition of activated carbon exhibited a significant influence on butanol fermentation.When 15 g/L activated carbon was added,the highest butanol concentration of 10.2 g/L was reached at 72 h.This study provides valuable guidance for utilization of corn stover for waste-free production of biofuels.