Effect of water in ionic liquids on CO₂ permeability in amino acid ionic liquid-based facilitated transport membranes

详细信息    查看全文

• 作者：Shohei Kasahara ; Eiji Kamio ; Toru Ishigami ; Hideto Matsuyama
• 关键词：Facilitated transport membrane ; Amino acid ionic liquid ; Carbon dioxide ; Gas separation ; Water-holding ability
• 刊名：Journal of Membrane Science
• 出版年：2012
• 出版时间：1 October, 2012
• 年：2012
• 卷：415-416
• 期：Complete
• 页码：168-175
• 全文大小：647 K

文摘

Amino acid ionic liquid-based facilitated transport membranes with tetrabutylphosphonium amino acid ionic liquids with glycine, alanine, proline and serine as the anion were prepared and their CO₂ permeation properties were evaluated from the physical and physicochemical properties of the amino acid ionic liquids. A tetrabutylphosphonium proline-based facilitated transport membrane showed an excellent CO₂ permeability of 14,000 Barrer, twice that of the others investigated, and a CO₂/N₂ selectivity of 100 at 373 K under dry conditions. Thermogravimetric measurement showed that the tetrabutylphosphonium proline had a relatively high water-holding ability compared with the other amino acid ionic liquids investigated. The strong water holding ability of tetrabutylphosphonium proline realized the large absorption amount of CO₂ and established a large concentration gradient for the CO₂-complex across the membrane. The large concentration gradient provided a large driving force for CO₂-complex transport through the membrane and increased CO₂ permeability.