Selective separation of H2S and CO2 from CH4 by supported ionic liquid membranes
Selective separation of H2S and CO2 from CH4 by supported ionic liquid membranes
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支持离子液体膜从 CH4 中选择性分离 H2S 和 CO2
DOI：
10.1016/j.memsci.2017.08.033
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发表时间：
2017
影响因子：
9.5
通讯作者：
MacFarlane Douglas R.
中科院分区：
文献类型：
--
作者：
Zhang Xiaomin;Tu Zhuoheng;Li He;Huang Kuan;Hu Xingbang;Wu Youting;MacFarlane Douglas R.
负载型离子液体膜（SILM）被认为是天然气改质的一种很有前途的介质。然而，目前的研究主要集中在CO2和CH 4的选择性分离上，而对H2S和CH 4以及H2S和CO2的选择性分离研究较少。本文系统研究了干燥条件下CH 4、CO2和H2S在中性和碱性离子液体中的渗透行为。计算了理想的CO2/CH 4、H2S/CH 4和H2S/CO2选择性。研究了阴离子种类、跨膜压差、温度等因素对单一气体渗透性和理想气体对选择性的影响。结果表明，中性离子液体（1-丁基-3-甲基咪唑四氟硼酸盐和1-丁基-3-甲基咪唑三氟甲磺酸盐）对CO2和H2S具有较高的渗透性，对CO2/CH 4和H2S/CH 4具有较强的选择透过性，可用于天然气中H2S和CO2的同时脱除。碱性离子液体（1-丁基-3-甲基咪唑乙酸盐）不仅对CO2和H2S具有很高的渗透性，而且对CO2/CH 4、H2S/CH 4和H2S/CO2具有上级选择性渗透，因此具有潜在的选择性脱除天然气中H2S的应用前景。此外，1-丁基-3-甲基咪唑乙酸盐对H2S和CO2有促进作用。据我们所知，这是第一次，促进运输的H2S在SILM的报道。
Supported ionic liquid membranes (SILMs) are considered as promising media for the upgrading of natural gas. However, most research has focused on the selective separation of CO2and CH4, paying little attention to the selective separation of H2S and CH4or H2S and CO2in SILMs. In this work, the permeability of CH4, CO2, and H2S in two different categories of ionic liquids (neutral and basic ionic liquids) were systemically investigated under dry conditions. The ideal selectivity of CO2/CH4, H2S/CH4, and H2S/CO2were calculated. The effect of anion species, transmembrane pressure difference, and temperature on the permeability of single gas and ideal selectivity of gas pairs were studied. It is found that neutral ionic liquids (1-butyl-3-methylimidazolium tetrafluoroborate and 1-butyl-3-methylimidazolium trifluoromethanesulfonate) show high permeability of CO2and H2S, and competitive permselectivity of CO2/CH4and H2S/CH4, and thus can be used for the simultaneous removal of H2S and CO2from natural gas. Basic ionic liquids (1-butyl-3-methylimidazolium acetate) show not only high permeability of CO2and H2S, but also superior permselectivity of CO2/CH4, H2S/CH4and H2S/CO2, and thus can be potentially used for selective removal of H2S from natural gas. Moreover, facilitated transport of H2S and CO2were observed in 1-butyl-3-methylimidazolium acetate. To the best of our knowledge, this is the first time that the facilitated transport of H2S in SILMs is reported.