摘要
在温和条件(90℃、常压)下,以无定形纤维素和微晶纤维素(MCC)为原料,考察1-丁基-3-甲基咪唑氯盐水溶液处理过程中纤维素溶解和结构变化规律。与MCC不同,无定形纤维素可溶解在60%~95%1-丁基-3-甲基咪唑氯盐水溶液中。处理时间和1-丁基-3-甲基咪唑氯盐含量是影响MCC结晶度指数、平均微晶尺寸和氢键强度的重要因素。与未处理样品聚合度(286)相比,处理后MCC的聚合度减小至235~254。研究结果有利于深入理解和优化离子液体水溶液预处理木质纤维生物质过程。
Dissolution of cellulose in 1-butyl-3-methylimidazolium chloride([C_4C_1im]Cl) aqueous solutions under mild conditions(90 ℃, ambient pressure) and its structure changed after dissolution were investigated using amorphous cellulose and microcrystalline cellulose(MCC) as feedstocks. Compared with MCC, amorphous cellulose could be dissolved in 60%-95% [C_4C_1im]Cl aqueous solutions. Treatment time and [C_4C_1im]Cl content were the main factors to influence the crystallinity index, average crystallite size and hydrogen bond intensity of MCC. Comparing with those untreated samples(286), the polymerization degree of MCC after treatment decreased to 235-254. The results of this study favored understanding and optimizing the process conditions to treat lignocellulosic biomass in ionic liquid aqueous solutions.
引文
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