基于酸性生物基离子液体预处理的木质素高效催化醇解制芳烃的研究

生物质资源的清洁高效转化，对于减轻环境和能源压力、实现经济可持续发展具有重要意义。作为自然界中唯一能提供大宗可再生芳香类化学品的非石油资源，木质素因结构复杂难以有效降解、产物组份繁杂选择性不可控等，限制了其高效转化利用，亟待开发新的反应工艺和高效催化体系。本项目拟制备酸性生物基离子液体对木质素进行预处理，促进其复杂大分子结构中β-O-4键的初步选择性解聚；设计高效的Ru-WOx/N-C多功能催化剂，使其通过抑制性加氢和选择性断裂CAr-O键定向制备芳烃类化学品；合成能更准确地模拟木质素复杂结构的低聚体作为模型化合物，探究木质素的催化醇解反应机理。通过研究，探明生物基离子液体阴阳离子结构、酸性等对木质素初步选择性解聚能力的影响机制，开发高效选择性加氢催化剂并揭示活性中心、结构等对催化性能的影响，阐明其催化木质素醇解制芳烃的反应机理，为提升木质素生物质转化的高效性与实用性提供理论和技术基础。

The worldwide energy crisis and related environmental impact have provoked extensive research and development programs on biomass conversion. Lignin is the only nature renewable resource which can provide large quantities of aromatic compounds．Due to the complex three-dimensional amorphous structure, lignin is difficult to effectively degrade. Its product composition is diverse and products selectivity is hard to control, which limit its practical application. Thus, efficient and selective catalytic systems and reaction processes are required for realizing the production of bio-chemicals from renewable lignin biomass. In view of these issues, in this project, we will use acidic bio-based ionic liquid to promote the preliminary depolymerization of β-O-4 linkages in the intricate macromolecule structure. We will design and synthesize efficient hierarchical porous Ru-WOx/N-C catalysts that enable the selective hydrogenolysis of the CAr-O bond of lignin to arenes. In order to understand the alcoholysis mechanism of lignin and identify the chemical pathways for the formations of arenes, we will synthesize a series of lignin dimer model compounds, which can simulate the polymeric structure of lignin more accurately compared with common monomer. Through the study of this project, the mechanism of anion-cation structure and acidity of bio-based ionic liquids on lignin depolymerization will be studied systematically. Multifunctional catalysts with unique selectivity will be developed and the relationship between catalytic performance and active site and structure will be revealed. Also, the mechanism of catalyzed degradation process of lignin to arenes will be theoretically investigated. Hopefully, this project will provide theoretical foundation and technical support for the efficient and practical transformation of lignin biomass.