关键词: 膜, 离子液体, 聚合物, 渗透, 二氧化碳捕集, 选择性

Abstract:

In recent years， global carbon dioxide emissions have exceeded 37 billion tons per year， which has severely affected the climate and the natural environment. There is an urgent need to develop carbon capture， utilization and storage technologies. Gas membrane separation, as a kind of process without phase change, could be launched under mild condition and concise operation. This technique, along with the continuous upgrade in both selectivity and permeability for membrane materials, has been the major tendency for global carbon capture. In this work, poly(ionic liquids), honored to be the next-generation membrane materials, are introduced. These new emergent materials, generally abundant with CO₂-philic groups, are hopeful to achieve ultra-high selectivity for carbon capture. The design and synthesis of specific cationic poly(ionic liquids), including both main-chain and branched-chain types, were summarized from the viewpoint of solution-diffusion mechanism for gas permeation. The emphases in this review are the selection of cationic and anionic groups, the selection of synthesis routes, and the micro-structure design for membranes. Furthermore, the advantages and the challenges to utilize those functional poly(ionic liquids) as membrane materials for CO₂ separation are discussed.

Key words: membrane, ionic liquids, polymer, permeation, CO₂ capture, selectivity