木质素不同级分的结构与其紫外线吸收能力的研究

Study on Structures and Ultraviolet Absorption Capacity of Fractionated Lignin

关键词:  木质素  有机溶剂分级  结构  紫外吸收

Key Words:lignin  solvent extraction  structure  ultraviolet absorption

摘要:采用乙酸乙酯、丁酮、丙酮依次处理竹硫酸盐木质素（KL），得到不同溶剂萃取的木质素及木质素残余部分，并对其进行表征。结果表明，有机溶剂分级可以将木质素按照相对分子质量有效地分离，提高了对木质素不同级分化学结构与紫外线吸收能力之间关系分析的准确性；其中乙酸乙酯萃取显著改善了木质素的均一性，分离了碳水化合物杂质，提高了有利于紫外线吸收的结构含量，使木质素总体紫外线吸收能力明显提高。

Abstract:Bamboo kraft lignin （KL） was fractionated with three organic solvents （ethyl acetate， butanone and acetone） sequentially and the lignin and lignin residues were obtained and characterized. The results showed that the organic solvent fractionation could effectively separate lignin according to the relative molecular quality and improve the accuracy of the analysis of the relationship between chemical structures of different levels of lignin and UV absorption capacity. The fractionation with ethyl acetate significantly improved the homogeneity of lignin， separated carbohydrate polymers impurity， and increased the content of structures conducive to UV absorption capacity， so that the overall UV absorption capacity of lignin was significantly improved.