Integrated sorption systems consisting of 1â:â1 mixtures of an alcohol-functionalized ionic liquid and a superbase were found to be effective for CO2 capture under atmospheric pressure, eliminating the use of volatile n-alkanols or water. Conversely, by using the current approach, there is no longer a requirement for maintaining scrupulously dry conditions. The effect of ionic liquid structure, choice of superbase, their relative ratios, the sorption temperature, and the reaction time on the absorption and release of CO2 were investigated. Our results demonstrate that (i) this integrated ionic liquidâsuperbase system is capable of rapid and reversible capture of nearly one mole of CO2 per mole of superbase, (ii) the captured CO2 can be readily released by either mild heating or bubbling with an insert gas (N2, Ar), and (iii) this novel CO2 chemisorption platform can be recycled with minimal loss of activity. This efficient and fully reversible catch-and-release process using non-volatile, task-specific ionic liquids provides an excellent alternative to current CO2 capture technologies, which are based largely around volatile alkanols or alkylamines. Furthermore, our integrated ionic liquidâsuperbase system can be used as a novel medium for supported liquid membranes, for which they demonstrate both good selectivity and permeability in model CO2/N2 gas separations.
研究发现,由醇官能化
离子液体和超级碱的 1:1 混合物组成的集成吸附系统可在大气压下有效捕获
二氧化碳,无需使用挥发性正烷醇或
水。相反,使用目前的方法,就不再需要保持严格的干燥条件。我们研究了
离子液体结构、超碱的选择、它们的相对比例、吸附温度和反应时间对
二氧化碳吸收和释放的影响。我们的研究结果表明:(i) 这种集成
离子液体-超级碱系统能够快速、可逆地捕获每摩尔超级碱中近一摩尔的
二氧化碳;(ii) 通过温和加热或用插入气体(N2、Ar)鼓泡,捕获的
二氧化碳可以很容易地释放出来;(iii) 这种新型
二氧化碳化学吸附平台可以循环使用,活性损失极小。这种使用非挥发性、任务特异性
离子液体的高效、完全可逆的捕获和释放过程,为目前主要基于挥发性烷醇或烷基胺的
二氧化碳捕获技术提供了极佳的替代方案。此外,我们的集成
离子液体超级碱系统可用作支撑液体膜的新型介质,在
二氧化碳/N2 气体分离模型中表现出良好的选择性和渗透性。