分离烟道气中二氧化碳的室温离子液体共混膜研究

Due to the high requirement of green house gas control in China, the purpose of this proposal is to develop room temperature ionic liquid (RTIL) based membrane materials with superior properties for separating CO2 from the flue gas. RTIL will be selected as the base material for this research. The molecular structures of the cations and anions of the RTILs will be carefully tuned to increase the affinity to CO2. Then, RTILs will be functionalized with “C=C” or “-NH2” groups and form polymeric RTIL via the UV-crosslink or imidization polymerization for the purpose of increasing the mechanical strength. After that, blend polymeric RTIL with different materials including: (1) nanoporous materials such as: zeolitic imidazolate framework (ZIF), (2) liquid state RTILs for achieving better CO2 permeability and CO2/N2 selectivity. The impact on the affinity to CO2 by different molecular structures of anions and cations and the separation properties of the RTIL based polymer blends to CO2/N2 gas pairs will be systemically studied. We will focus on exploring the impact on the CO2 separation property and membrane mechanical strength by adjusting the compositions of the individual components; and evaluate the membrane separation performance at different temperatures. These novel membrane materials will have great potential for CO2 separation applications.

结合我国控制碳排放的需求，本课题的目标是研发具有优异烟道气/CO2分离性能的膜材料。首先以室温离子液体（RTIL）为基材，设计其阴、阳离子结构，提高对CO2的亲和力。然后，通过季铵化反应，在RTIL的阳离子上引入C=C或-NH2基团，进而采用紫外光照或亚胺化聚合方法，制备聚合态RTIL，改善RTIL膜的机械强度。最后采用共混方法，将不含聚合反应基团的RTIL和具有高气体通量的纳米多孔材料，如沸石咪唑酯骨架结构材料（ZIF），加入到聚合态RTIL中，提高CO2渗透率和CO2/N2的选择性。系统研究RTIL阴、阳离子结构对CO2溶解性能的影响以及共混膜的CO2/N2分离性能。重点研究共混膜中聚合态RTIL、液态RTIL以及纳米多孔材料不同的配比与CO2渗透率、CO2/N2选择性和膜的机械稳定性的关系。着重研究不同温度对气体分离性能的影响。该材料在CO2分离领域将具有潜在的应用前景。

合成了含氨基的聚合态离子液体聚合物，研究了其气体分离性能。设计并合成了一系列热引发交联聚酰亚胺材料。交联聚酰亚胺的CO2渗透率高达1800barrer，CO2/N2选择性达到20，CO2/CH4选择性为20.综合性能超过“2008 Robeson Upper Bound”，完成了项目设计性能指标。此外，系统研究了单体结构对玻璃态聚合物膜的气体传质性能的影响。发现了朝格尔碱结构对比聚酰亚胺结构在分子筛分方面的优势，开发了基于朝格尔碱结构的螺旋主链聚合物。发表论文共20篇，其中SCI论文13篇，Top论文8篇，申请专利1项。