四氢糠醇-稀酸体系预处理杂交狼尾草的试验研究

以杂交狼尾草为研究对象,采用四氢糠醇-硫酸体系在常压较低温度下进行预处理研究,优化该预处理体系得到最佳预处理条件为0.1 mol/L硫酸、反应温度120℃、反应时间2 h、固液比为1∶12,在此条件下残渣中纤维素、半纤维素的保留率分别为86.17%、9.01%,木质素脱除率为98.16%;对预处理残渣进行酶解,72 h时酶解率可达99.01%,比未处理原料的酶解率高2.6倍。通过使用扫描电镜、X射线衍射、红外光谱、热重分析等方法对预处理后残渣及原料的组成及结构进行分析测试,表明四氢糠醇-硫酸预处理能有效脱除木质素及半纤维素,破坏平整的原料表面结构,提高原料的酶解率。

RESEARCH ON PRETREATMENT OF HYBRID PENNISETUM WITH TETRAHYDROFURFURYL ALCOHOL/DILUTE ACID SYSTEM

The hybrid Pennisetum is pretreated by tetrahydrofurfuryl alcohol(THFA)/H2SO4 system at atmospheric pressure and mild temperature. The optimum pretreatment conditions are obtained to be 0.100 mol/L sulfuric acid,120 ℃ the reaction temperature,1∶12 solid-liquid ratio,2 h reaction time. Under these conditions the cellulose retention rate,the hemicellulose retention rate and the lignin removal rate is 86.17%, 9.01% and 98.16%,respectively. The enzymatic digestibility of substrates reaches 99.01% after 72 h enzymatic hydrolysis, which is 2.6 times higher than that of untreated raw material. The composition and structure of the raw material and the pretreated residues are analyzed by SEM,XRD,FT-IR and TGA. The results consistently indicate that the pretreatment by THFA/H2SO4 can effectively remove lignin and hemicellulose,and destroy the smooth surface structure of raw materials so as to enhance the enzymatic hydrolysis rate of lignocellulose.