生物质基1,3-丙二醇高效制备中纳米复合催化剂的界面增强效应及氢解机理

Considering the conventional supported catalysts showed low activities and selectivities in hydrogenolysis of biomass-derived polyols (sorbitol,xylitol and glycerol) to the value-added 1,3-propanediol,this project aims to fabricate functional assembly nano-composite catalysts with interfaces for two-step hydrogenolysis of sorbitol/xylitol to glycerol (metal-alkali), which is followed by hydrogenolysis to 1,3-propanediol(metal-acid) in terms of activity and selectivity.By using chemical synthesis in solution,this project will prepare the bifunctional nano-composite catalysts with metal-base and metal-acid interfaces with well-defined sizes and geometries due to that the interface sturcture and property could be tailored by the size and shape of metal and acid/base kinds.With the aid of enhanced effects by electron transfer at the metal-base and metal-acid interfaces,this project will investigate the synergistic dehydrogenation of C2 atom in sorbitol and/or C1 or C2 atom in xylitol and selective scission of C3-C4 bond in sorbitol and/or C2-C3 bond in xylitol at metal-base interface, and the cooperative activation of primary hydroxyl of glycerol to alkoxide species and cracking of its second hydroxyl by attack of over spilled hydrogen at metal-acid interface.Furthermore,this project will also study the synergistic hydrogenolysis mechanism during the biomass-derived polyols transformation,and elucidate the activation behavoirs of reactants and the transferring approaches of key intermediates over the functional assembly nano-cataysts.By these investigation,this project will provide scientific fundament and technical support for selective hydrogenolysis of biomass-derived polyols to value-added chemicals.

本项目为解决常规负载型催化剂上生物质多元醇选择性氢解为高附加值1,3-丙二醇中存在的活性和选择性低下问题，构建具有金属-酸（碱）界面结构的功能集成纳米复合催化剂体系应用于生物质基山梨醇/木糖醇选择性氢解为丙三醇（金属-碱）和丙三醇选择性氢解为高附加值的1,3-丙二醇（金属-酸）的两步转化路径。(1)通过溶液化学法设计合成尺寸和形貌（高活性晶面集中暴露）可控的金属-酸（碱）催化剂以调节其界面结构与性质。(2)借助催化剂界面电子转移引导的增强效应，阐明山梨醇氢解为丙三醇的选择性脱氢（金属中心）与C-C键断裂（碱中心），以及丙三醇伯羟基配位吸附（酸中心）和氢溢流条件下增强的仲羟基活化裂解（金属中心）的协同反应机理和关键中间产物生成与转化路径。通过项目研究，为生物质基1,3-丙二醇化学品的高效制备提供理论基础与技术支撑。

本项目为解决常规负载型催化剂上生物质多元醇选择性氢解为高附加值1,3-丙二醇中存在的活性和选择性低下问题，按照项目研究计划，围绕项目提出的1,3-丙二醇高效制备中纳米复合催化剂的界面增强效应及氢解机理关键科学问题开展深入系统的研究工作，并在以下几个方面取得了重要进展：（1）制备了金属-酸耦合催化剂，催化纤维素一步水解制备山梨醇，山梨醇的产率高达85.5%；进一步优化工艺条件，将ZPA和纤维素混合球磨后再耦合Ru/C进行水解加氢C6糖醇的产率为90.3%；探索出了金属-酸耦合催化纤维素加氢途径。（2）制备了金属-碱协同催化催化剂，催化C5/C6糖醇氢解制备小分子多元醇，探究了不同碳链长度的多羟基化合物的氢解行为，以高附加值的C2-C3多元醇为主要目标产物，为C2-C3多元醇的生产提供更多途径，得到的1，2-丙二醇的产率为23%。（3）长径比可控的金属Co纳米棒的可控合成及其在甘油选择性氢解制备1,3-丙二醇中的反应机理与产物控制研究；项目执行两年来，发表论文15篇，其中SCI收录12篇；申请发明专利2件；依托项目研究已培养硕博研究生6人；研究成果获得广东省自然科学一等奖1项，获得由联合国工业发展组织颁发的“2016年度全球可再生能源领域最具投资价值的领先技术蓝天奖”1项，获得科技厅组织的成果鉴定2项。项目完成了中期任务，达到了预期目标。