Constructing ether-rich and carboxylate hydrogen bonding sites in protic ionic liquids for efficient and simultaneous membrane separation of H_(2)S and CO_(2) from CH_(4)  

作　　者：Ping Zhang Xingyun Ma Zhuoheng Tu Xiaomin Zhang Xingbang Hu Youting Wu 

机构地区：[1]Separation Engineering Research Center,Key Laboratory of Mesoscopic Chemistry of MOE,School of Chemistry and Chemical Engineering,Nanjing University,Nanjing,210023,China [2]Institute of Green Chemistry and Engineering,Nanjing University,Suzhou,215163,China

出　　处：《Green Energy & Environment》2025年第3期560-572,共13页绿色能源与环境(英文版)

基　　金：sponsored by the National Natural Science Foundation of China (Nos. 22308145, 22208140, 22178159, 22078145);Natural Science Foundation of Jiangsu Province (BK20230791);Postgraduate Research Innovation Program of Jiangsu Province (KYCX24_0165)。

摘　　要：Removing H_(2)S and CO_(2)is of great significance for natural gas purification.With excellent gas affinity and tunable structure,ionic liquids(ILs) have been regarded as nontrivial candidates for fabricating polymer-based membranes.Herein,we firstly reported the incorporation of protic ILs (PILs) having ether-rich and carboxylate sites (ECPILs) into poly(ether-block-amide)(Pebax) matrix for efficient separation H_(2)S and CO_(2)from CH_(4).Notably,the optimal permeability of H_(2)S reaches up to 4310 Barrer (40C,0.50 bar) in Pebax/ECPIL membranes,along with H_(2)S/CH_(4)and (H_(2)StCO_(2))/CH_(4)selectivity of 97.7 and 112.3,respectively.These values are increased by 1125%,160.8%and 145.9%compared to those in neat Pebax membrane.Additionally,the solubility and diffusion coefficients of the gases were measured,demonstrating that ECPIL can simultaneously strengthen the dissolution and diffusion of H_(2)S and CO_(2),thus elevating the permeability and permselectivity.By using quantum chemical calculations and FT-IR spectroscopy,the highly reversible multi-site hydrogen bonding interaction between ECPILs and H_(2)S was revealed,which is responsible for the fast permeation of H_(2)S and good selectivity.Furthermore,H_(2)S/CO_(2)/CH_(4)(3/3/94 mol/mol) ternary mixed gas can be efficiently and stably separated by Pebax/ECPIL membrane for at least 100 h.Overall,this work not only illustrates that PILs with ether-rich and carboxylate hydrogen bonding sites are outstanding materials for simultaneous removal of H_(2)S and CO_(2),but may also provide a novel insight into the design of membrane materials for natural gas upgrading.

关 键 词：H_(2)S Protic ionic liquid Multi-site hydrogen bonding interaction Membrane separation Natural gas purification 

分 类 号：O64[理学—物理化学]