NaOH-H_2O_2溶剂体系下玉米秸秆的组分分离规律研究  

The Component Separation of Corn Stover in NaOH-H_2O_2 System

作　　者：李聪[1] 张莉[1] 张龙[1] 

机构地区：[1]吉林省石化资源与生物质综合利用工程实验室长春工业大学化工学院,长春130012

出　　处：《中国粮油学报》2015年第1期20-26,共7页Journal of the Chinese Cereals and Oils Association

摘　　要：研究了NaOH-H2O2组成的碱溶剂体系对玉米秸秆的溶解规律,并结合酸沉、醇析方法分离出了3种主要成分,研究了过氧化氢浓度、pH、液固比、温度、时间对玉米秸秆组分分离过程的影响。结果表明:碱溶剂处理后的剩余固体物质是纤维素和不溶物,滤液经酸沉后的固体为木质素,酸沉后的滤液调pH后醇析所得的固体为半纤维素。试验确定了分离过程的最佳工艺条件:过氧化氢浓度5%,pH=12,反应时间3 h,溶解温度60℃,液固比30 m L/g。在此条件下,纤维素回收率84.2%,木质素回收率为66.6%,半纤维素回收率96.7%,滤液经4次循环使用,纤维素回收率82.7%,木质素回收率67.6%,半纤维素回收率97.4%。碱处理及酸沉、醇析后剩余固体的结构分析证明了此方法的可行性。The dissolution of corn stover in alkaline solvent system composed of NaOH - H2O2 was studied in the paper. The separation of the corn stover ingredients combined with acid precipitation and ethanol extraction was proposed. The results have proven that the main residual after the treatment in alkali solvent was mainly cellulose; the filtrate by the acid precipitation of the liquor was lignin; and the solid after the anhydrous ethanol extraction of the liquor was hemicellulose. The optimal dissolution conditions was determined by single - factor experiment to be as fol- lows： the concert ration of H2O2 was 5% , pH 12, dissolution temperature 60 ℃, dissolution time 3.0 h, the ratio of liquid to solid 30 mL/g. Fourier transform infrared spectroscopy, scanning electron microscope, X - ray diffraction and nuclear magnetic resonance were employed to identify the separated structure of the components ; the cellulose re- covery yield could achieve to 84.2%, the lignin recovery yield after acid precipitation was about 66.6% and hemicel- lulose recovery yield after ethanol extraction was about 96.7%. After recycling the solvent 4 times, the cellulose yield could achieve to 82.7%, the lignin yield after acid precipitation was about 67.6% and the hemieellulose yield after anhydrous ethanol extraction was about 97.4%.

关 键 词：玉米秸秆 木质素 半纤维素 纤维素 组分分离 NaOH-H2O2体系 

分 类 号：TQ35[化学工程]