离子液体气-液界面结构和界面传递的机制和调控

Reactions such as hydrogenation and hydroformylation using ionic liquids (ILs) as medium are green and efficient gas-liquid multiphase reactions, and have attracted great interest in recent years. Nevertheless, the mass-transfer resistance of those processes is usually large, which has limited the utilization of those processes. One essential scientific problem in the process intensification of IL-based gas-liquid reactions is the mechanism and adjustment of the gas-liquid interfacial structure and interfacial mass transfer of ILs. ILs are compounds composed totally by ions, and their interfacial structure has features such as high interfacial charge density, intricate arrange and orientation behavior, sensitivity to solutes, which are quite different from the case of common gas-liquid biphasic systems. However, corresponding researches have not been systematically carried out yet. In this project, we will study the interfacial structure and property of IL-based gas-liquid biphasic systems by methods including non-linear spectrum and molecular simulation, investigating the effect of IL structure and the reactant/product/catalyst on the interfacial structure and property. The mass-transfer of typical gases at the gas-liquid interface will also be studied. The mechanism and adjustment of the gas-liquid interfacial structure and interfacial mass transfer of ILs will be tried to be demonstrated. The results of this project will be highly instructive for the process intensification of IL-based gas-liquid reactions.

以离子液体为介质的加氢、羰基合成等反应是一类绿色、高效的新型气-液反应过程，具有潜在的工业应用前景，但该过程传质阻力普遍较大，这已成为限制其应用的主要因素之一。离子液体气-液两相反应过程强化的关键科学问题是离子液体气-液两相体系介观尺度的界面结构和界面传递过程的内在机制和调控规律。离子液体是完全由离子组成的物质，其气-液界面结构具有电荷密度高、排列取向规律复杂、易受溶质影响等特点，显著不同于常规气-液两相体系，目前相关研究尚未系统开展。为此，本项目拟采用非线性光谱和分子动力学模拟等手段研究离子液体气-液两相体系的界面结构和界面性质，研究离子液体化学结构、反应物/产物/金属催化剂等溶质种类和含量对界面结构和性质的影响规律，进一步研究典型气体在离子液体气-液界面的传递特性，探索离子液体气-液界面结构和界面传递的机制和调控规律，为离子液体气-液反应过程的传质强化提供理论依据。

离子液体是近年来新兴的一类液体软材料，具有几乎不挥发、结构和性质可设计、对气体和金属催化剂溶解性能良好等特点，为气体吸收及气-液反应过程的发展提供了新的平台。然而以离子液体为介质的非均相过程传质阻力普遍较大，已成为限制其应用的主要因素之一。离子液体气-液两相过程强化的关键科学问题是离子液体气-液两相体系介观尺度的界面结构和界面传递过程的内在机制和调控规律。离子液体是完全由离子组成的物质，其气-液界面结构具有电荷密度高、排列取向规律复杂、易受溶质影响等特点，显著不同于常规气-液两相体系。本项目系统研究了在气-液两相反应和气体分离领域有重要研究和应用价值的酸性功能化离子液体和碱性功能化离子液体的气-液界面结构，获得了多种离子液体气-液界面的基团组成、排列和取向信息，阐明了阴/阳离子结构、取代基引入等因素对界面结构的影响。此外，本项目还拓展研究了气体分子在一类新型离子液体中的气-液平衡特性。