微波辐射催化木素溶剂解聚的化学反应机理研究

项目名称： 微波辐射催化木素溶剂解聚的化学反应机理研究

项目编号： No.21466022

项目类型： 地区科学基金项目

立项/批准年度： 2015

项目学科： 有机化学

项目作者： 刘玉环

作者单位： 南昌大学

项目金额： 50万元

中文摘要： 木素是由具有苯丙烷结构的单体聚合成的体型大分子聚合物，是生物质基酚类化学品的可再生宝藏。从木素解聚获取低聚态组分或木素单体,作为酚类化学品制备的前体材料,是生物质能源与材料领域研究热点。已经明确了酚型木素比非酚型木素反应活性高；木素热裂解、水（溶剂）热裂解主要作用于联结木素单体之间的醚键，如β-O-4联结；而联苯型的C-C键如5-5'联结解聚要困难很多，一般都须借助高温高压、强氧化剂氧化或加氢还原的方法才能部分实现。由于反应条件苛刻，目前木素解聚反应选择性差，反应产物多为偏大的多聚体，且因次生缩合残留大量焦化产物。本研究拟采用微波辐射、催化剂、溶剂（溶胀剂和供氢体）共建温和（常压和溶剂回流温度）的木素绿色化学解聚环境，借助木素单体模型化合物、β-O-4型和5-5'联苯型二聚体模型化合物和经纯化的醇溶木素，探讨甲氧基、β-O-4和5-5'联结解聚的多组分串联反应机理并建立木素解聚动力学模型。

中文关键词： 木素；微波辐射；催化；溶剂裂解；多组分串联反应

英文摘要： Lignin is a complex heteropolymer of trans-p-coumaryl, coniferyl, and sinapyl alcohols, and is a potential source of biobased phenolic compounds. The fragmentation of lignin into smaller oligomeric fraction has attracted more and more attention. It is revealed that depolymerisation of lignin macromolecules in pyrolysis and hydrothermal process mainly by cleaving the ether bonds, like β-O-4, while the C-C bond like 5-5' linkages are much more difficult to be degraded under mild condition, usually high temperature and high pressure combined with oxidant or hydrogen donor is necessary, and also the phenol type lignin is much reactive than non-phenol type lignin. Drastic reaction condition weakened the chemoselectivity, that result in a wide distribution of polymerization degree of the degraded lignin fragment and residual char formed by secondary polymerization of oligomeric fractions. In present proposal, microwave radiation, catalyst, organic solvents and their mixture (swelling agent and hydrogen donor) will be adopted to construct a mild green chemical environment for lignin depolymerisation. By means of monomer, dimer , oligomeric compounds, and fractionated bamboo organosolv lignin, with methoxy group, β-O-4 linkage, and 5-5' linkages, the mechanism of chemoselectivity and multicomponent tandem reaction of catalytic solvolysis of lignin with the aid of microwave radiation will be investigated,and finaly the dynamical of microwave aid catalytic lignin solvolysis model will be set up. The result of present research will provide us a new idea to extract biomass based aromatic chemical precursors much efficiently and environment-friendly.

英文关键词： lignin;microwave radiation;catalytic;solvolysis;Multicomponent tandem reaction