[Bmim][BF4]/MEA 混合水溶液吸收CO2的吸收性能与液液分相机理  

Absorption performance and stratification mechanism of biphasic CO_2 absorbent [Bmim][BF_4]/MEA aqueous mixtures

作　　者：徐令君 QI Yang 王淑娟[1] XU Lingjun;QI Yang;WANG Shujuan(Key Laboratory for Thermal Science and Power Engineering of Ministry of Education,Beijing Engineering Research Center for Ecological Restoration and Carbon Fixation of Saline-Alkaline and Desert Land,Department of Energy and Power Engineering,Tsinghua University,Beijing100084,China;CSIRO Manufacturing,Clayton,Victoria,3168,Australia)

机构地区：[1]热科学与动力工程教育部重点实验室,北京市盐碱及荒漠化地区生态修复与固碳工程技术研究中心,清华大学能源与动力工程系,北京100084 [2]CSIRO Manufacturing,Clayton,Victoria,3168,Australia

出　　处：《化工学报》2018年第12期5112-5119,共8页CIESC Journal

基　　金：国家自然科学基金项目(51576108).

摘　　要：对液液两相CO_2吸收剂1-丁基-3-甲基咪唑四氟硼酸盐([Bmim][BF_4])/乙醇胺(MEA)混合水溶液吸收性能进行了实验测定,研究了离子液体[Bmim][BF_4]的引入对吸收性能和液液分相的影响,并通过定量碳谱核磁共振法对分相机理和各相中的物质分布进行分析。研究结果表明,一定配比的[Bmim][BF_4]/MEA混合水溶液吸收CO_2之后会出现互不相溶的液液两相,这种现象伴随着CO_2产物的富集;导致液液分相的原因是氨基甲酸盐浓度的增大;随着[Bmim][BF_4]质量分数的增大,溶液吸收速率呈现出先增大后减小的趋势;分层后H_2O主要分布在富液相,[Bmim][BF_4]主要分布在贫液相,H_2O的质量分数直接影响分层后富液相的传质性能。The absorption performance of liquid-liquid biphasic CO2absorbent aqueous mixture of1-butyl-3-methylimidazoliumtetrafluoroborate([Bmim][BF4])and monoethanolamine(MEA)was measured,and the effects of[Bmim][BF4]on the absorption properties and stratification were investigated.The stratification mechanism and substance distribution were analyzed with quantitative13C nuclear magnetic resonance(NMR)method.The results showed that the liquid-liquid stratification would occur when loaded with CO2,which was accompanied with the enrichment of the reaction products of CO2.The cause of the liquid-liquid stratification is the increase of the concentration of carbamates.The absorption rates of absorbents increase first and then decrease with the increase of the mass fraction of[Bmim][BF4].H2O is mainly distributed in the rich phase after stratification,and[Bmim][BF4]is mainly distributed in the lean liquid phase.The mass fraction of H2O directly affects the mass transfer performance of the rich liquid phase.

关 键 词：二氧化碳捕集 液液两相吸收剂 吸收 离子液体 乙醇胺 

分 类 号：TQ028.8[化学工程]