木质素和单宁可控制备纳米颗粒及其在单酚加氢中的催化应用

木质素和单宁是可再生植物生物质中重要组分，含有大量苯环单元和多种亲/疏水性官能团。本项目拟以植物生物质为原料，采用溶剂热法提取获得纯度较高的木质素寡聚物和单宁；调控其官能团分布和苯环π-π相互作用，研究制备由疏水核和亲水壳组成的木质素-单宁纳米颗粒；利用单宁的络合和还原能力，制备负载型金属纳米单质材料，并应用于催化木质素单酚加氢。主要包括：1）优化催化溶剂体系参数，调控生物质降解所得木质素寡聚物结构；2）调控纳米颗粒制备过程中水溶剂交换的关键参数、以及木质素寡聚物和单宁结构，研究其对纳米颗粒性质的协同影响机制；3）调控金属离子在纳米颗粒上络合和还原行为，探究负载型金属纳米单质催化剂在木质素单酚加氢过程中的催化性能和机理。研究结果可望建立一种精准调控木质素-单宁纳米颗粒性质的理论和方法，为制备可应用于单酚催化加氢的负载型金属纳米单质催化剂提供技术支撑，为植物生物质高值化利用提供新的研究方向。

Lignin and tannin, as the main components in sustainable lignocellulosic biomass, contain a large amount of phenyl repeating units and diverse hydrophilic and hydrophobic groups. In this project, lignin-based oligomers (lingo-oligomers) and soluble tannin with high purity will be obtained from the solvothermal extraction of lignocellulose in cosolvent system. Then, lignin-tannin complex nanoparticles (LTNPs) with hydrophobic core and hydrophilic shell will be generated by controlling the π-π interaction between the phenyl groups and adjusting the functional groups in the lingo-oligomers and tannin. Owing to the coordination and reducing ability of tannin, supported metal nanoparticles can be prepared using LTNPs and used for catalyzed hydrogenation of monophenols. The main contents of the project will include: 1) influence of key parameters of catalytic solvothermal systems on the structure of the obtained lingo-oligomers; 2) effect of several typical parameters during the LTNPs’ preparation process and structural features of lingo-oligomers/tannin on the properties of LTNPs; 3) coordination and reducing behavior of metal ions on LTNPs, and mechanistic study on catalytic hydrogenation of monophenols using supported metal nanoparticles. This project will hopefully establish a comprehensive theory and method to accurately control the properties of LTNPs for further preparation of supported metal nanoparticles applied into catalytic hydrogenation of monophenols, which can also provide a new research direction for value-added utilization of lignocellulose.