二元离子液体强化秸秆预处理

为了提高生物质秸秆的溶解率、优化秸秆组分再分布，采用1-丁基-3-甲基咪唑氯盐(Bmim]Cl)和1-乙基-3-甲基咪唑醋酸盐(Emim]OAc])的二元离子液体混合体系，考察溶剂组成、反应温度和处理时间三因素对预处理的影响。结果表明，随着Bmim]Cl在二元离子液体中摩尔比的升高，秸秆溶解率呈先上升后下降的趋势；纤维素在处理后秸秆中所占比例也遵循此规律。随着温度升高，溶解率逐渐增加，当温度超过100℃时，二元离子液体溶解液的黏度发生突变，秸秆发生变性；此外，随着处理时间的延长，溶解率逐渐升高，但是超过3 h以后，溶解效果提升并不明显。综合各因素作用效果，确定最佳反应温度为90℃，最佳处理时间3 h。在此条件下，秸秆的溶解率达到46.53%，经处理后秸秆中纤维素比例达到55.77%。

Enhanced pretreatment of cornstalks by binary ionic liquids

In order to promote biomass dissolution and optimize distribution of cornstalk components, 1-butyl-3-methylimdazolium chloride (Bmim]Cl) and 1-ethyl-3-methylimidazolium acetate(Emim]OAc]) were used. Effect of solvent ratio, temperature and time on pretreatment was investigated. As a result, with the rise of Bmim]Cl, cornstalk dissolution shows an inverted “V” change tendency, and the same trend occurs to cellulose content in pretreated cornstalk. Furthermore, the dissolution rate increases with the time and temperature. However, when the temperature was over 100℃, the physical properties of dissolution system would change dramatically. Besides, more than 3 h treatment would not improve the dissolution performance. So the optimal condition is 90℃, 3 h. Under these conditions, dissolution of cornstalk is up to 46.53%, and cellulose in pretreated cornstalk is also concentrated to 55.77%.