大连工业大学学报2017，Vol.36Issue(5)：338-342,5.
玉米秸秆纤维素乙醇残渣木素碱溶/酸析分级与表征
Fractionation and characterization of lignin extracted by alkaline extraction/ acid precipitation of residual corn stalk in ethanol production
摘要
Abstract
Lignin was extracted from corn stalk residues of cellulosic ethanol refining by large liquid ratio sodium hydroxide at room temperature , using hydrochloric acid as precipitation agent . T he lignin precipitation was fractionated sequentially by acidification at different pH (10 ,8 ,6 ,4 and 2) . The lignin samples were analyzed and characterized by ion chromatography ,GPC ,FT-IR ,TG and DSC . The results showed that lignin fractionation by alkali-soluble/acid precipitation contained carbohydrate ,and the carbohydrates content increased but the purity of lignin decreased with the decrease of pH .The average molecular weight of lignin decreased gradually with pH decrease .The polydispersity indices in acid precipitation reached to the lowest that was 1 .67 at pH 6 .The lignin prepared by fractional precipitation has lower thermal stability at lower pH than that of higher pH . FT-IR spectrum result showed that the functional groups of lignin fractions structure are similar , w hich contain three kinds of structural units such as syringyl ,guaiacyl and p-hydroxy phenyl .关键词
玉米秸秆/纤维素乙醇残渣/木素分级/碱溶/酸析沉淀Key words
corn stalks/cellulosic ethanol residue/lignin fractionation/alkali-soluble/acid precipitation分类
轻工纺织引用本文复制引用
刘欢,王兴,周景辉..玉米秸秆纤维素乙醇残渣木素碱溶/酸析分级与表征[J].大连工业大学学报,2017,36(5):338-342,5.基金项目
国家自然科学基金项目(31470604). （31470604）
