化石资源的过度消耗及因此产生的环境问题驱动了生物质资源各组分转化为燃料、化学品及材料的研究发展.木质素是自然界最丰富的可再生芳香碳氢资源,也是生物质中最难以实现高值化利用的组分.将木质素催化降解生成苯酚类单体化合物是其高值化利用的关键,因此开发新型催化体系对于提高当前生物精炼产业经济效益具有重要意义.本文利用钌碳耦合碱催化体系,系统考察了三倍体毛白杨的直接催化还原反应.三倍体毛白杨原料中的木质素组分优先降解为高得率的苯酚单体化合物,同时保留碳水化合物(纤维素及半纤维素)组分.木质素二聚模型化合物研究结果表明,在钌碳催化体系中引入碳酸铯可以导致木质素β-O-4结构单元中Cβ-O和Cβ-Cγ键的断裂,从而生成含有乙基侧链的苯酚单体(C2).通过动力学及分离物种活性研究确定反应中观测到的二聚烯醚产物是木质素β-O-4降解的副产物.本文以木质素降解得到的苯酚类单体产率、选择性、木质素脱除率以及碳水化合物保留率等主要参数作为考察指标,系统研究了碱的种类和用量、反应温度、时间以及氢气压力等对三倍体毛白杨木屑催化还原降解的影响.结果 表明,采用钌碳耦合碳酸铯体系,木质素生物大分子不仅降解为丙基、丙醇基取代的C3苯酚单体,同时生成部分C2苯酚产物,C2苯酚与C3苯酚的产物比值与碱的浓度呈现线性相关.通过钌碳耦合碳酸铯体系得到的碳水化合残渣具有较高的纤维素保留率.酶解对照实验发现,碱参与的催化还原降解反应得到的碳水化合物更易于酶解转化,这表明碱的加入可以有效地破解生物质中的抗降解屏障,从而提高酶解效率.本研究不仅提供了木质素高值化利用的方案,同时实现了生物质组分拆解、抗降解屏障破除及各组分的分级利用.“,”Lignin,which is the most recalcitrant component of lignocellulosic biomass,is also the most abun-dant renewable aromatic resource.Herein,reductive treatment of triploid poplar sawdust by the integration of catalytic Ru/C and a base,which afforded high yields of phenolic monomers from the lignin component and a solid carbohydrate pulp,is reported.The introduction of Cs2CO3 led to the generation of C2 side-chained phenols through the cleavage of Cβ-O and Cβ-Cγ bonds in β-O-4 units in addition to C3 side-chained phenols;the relationship between C2 and C3 was dependent on the base dosage.The reaction conditions,including base species,temperature,time,and H2 pressure,were optimized in terms of phenolic product distribution,delignification degree,and carbohydrate retention.The carbohydrate pulps generated from reductive catalytic fractionation in the presence of Cs2CO3 were more amenable to enzymatic hydrolysis,indicating that this treatment of biomass constituted the fractionation of biomass components together with the breakdown of biomass re-calcitrance.