耦合溶剂、NaCl和改性碳材料催化二聚糖转化为高附加值化学品的机理

以开发利用纤维素和半纤维素为背景，以二聚糖为模型化合物，以发展绿色高效的将二聚糖直接转化为呋喃类、乙醇醛、乳酸、乙酰丙酸、γ–戊内酯等高附加值化学品的催化剂体系为目标，采用高精度的分子力场和量子力场相结合的方法，尝试发展适宜于二聚糖在溶剂介质中转化的分子动力学模拟的新方法，探明NaCl在溶剂介质中正负离子对的结构、及其与多羟基二聚糖作用的反应活性位点和分子作用机制，构建溶液中碳材料界面上的活性中心（Al、W、Ru、–RSO3H和–RNH2等）活化糖类中间体中O–H、C–OH、C–H、C–C、C–O–C等化学键的协同反应机理，获得其结构与性能的关系。积累和总结由二聚糖高选择性合成高附加值化学品的规律性认识。以此为依据，理性设计兼具解聚、异构、脱水、逆羟醛缩合/羟醛缩合、氧化/还原等多功能碳材料催化剂体系，实施实验验证。为理性设计纤维素和半纤维素高效转化利用催化体系提供理论依据。

With the dwindling supply of fossil fuel, the renewable lignocellulosic biomass has attracted more and more attention and become an important raw material for the production of valuable chemicals. Lignocellulosic biomass is composed of cellulose, hemicellulose, and lignin, with the associated highly complex composition and hydrophobic interaction. Among them, the convertion of cellulose and hemicellulose into high value-added chemicals, such as, furans, glycolaldehyde, lactic acid, levulinic acid, and γ-pentalactone, has attracted growing interest. The disaccharide can be preferred as the model compound of cellulose and hemicellulose. For the conversion of disaccharide to high added-value chemicals in protic or plor aprotic solvents, the method of combining high precise quantum force field with molecular force field are explored to investigate the catalytic reaction mechanisms. The contents of the present investigation are as follows: (a) to propose a new method of molecular dynamics simulation for the conversion of disaccharide in solvent medium, (b) to explore the structure of Na+–Cl– ion pair in solvent medium, and its effect on the conversion of disaccharide with polyhydroxy, (c) to acquire the reaction mechanism for the activating typical chemical bonds (O–H, C–OH, C–H, C–C, C–O–C and so on) in disaccharide, catalyzed by the grafted carbon materials with active sites, such as, W, Ru, – RSO3H and – RNH2, (d) to provide insight into the intrinsic relationship between structure and property of active species, and (e) to develop the rational design for the catalytic system of multi-functional carbon materials, including depolymerization, isomerization, dehydration, reverse aldol condensation, aldol condensation, oxidation, and reduction, and so on. Furthermore, typical experimental verification will be carried out. The present investigation is helpful to develop the green and effective catalytic system for the conversion of cellulose and hemicellulose into high added-value chemicals. It is very important to explore the rule of the complicated system kinetics, to utilize reasonably resource, to control envirnomeantal pollution, to innovate the low-carbon technology, and to bring into effect on the continuous development of economy.