水稳定功能化Cu-BTC基混合基质膜的制备及其CO_(2)分离应用

Preparation of waterstable functionalized Cu-BTC based mixed-matrix membranes and its application in CO_(2) separation

为提高混合基质膜(mixed-matrix membranes,MMMs)对真实烟道气和含水天然气的分离性能,通过柠檬酸(citric acid,CA)功能化制备了具有高水稳定性的CA-Cu-BTC填料,并将其与Pebax 1657聚合物共混制备了系列不同掺杂量的MMMs,考察了25℃饱和水蒸气下所制备CA-Cu-BTC/Pebax膜的CO_(2)/N_(2)分离性能。结果表明:与纯Pebax膜相比,制备的MMMs具有更好的CO_(2)渗透性和CO_(2)/N_(2)选择性,在CO_(2)渗透通量为837.2 GPU(1 GPU=3.35×10^(-4)μmol/(m^(2)·s·MPa))时,CO_(2)/N_(2)选择性为49.1。此外,CA功能化改性赋予填料的高水稳定性,使得本文制备的MMMs具备了应用于实际工业气体分离的潜力。

In order to improve the separation performance of mixed-matrix membranes(MMMs) for flue gas and watercontaining natural gases,a water stable CA-Cu-BTC filler was synthesized through functionalization with citric acid(CA),and MMMs with different content of filler were prepared by embedding the obtained CA-Cu-BTC in Pebax 1657 matrix.The CO_(2)/N_(2)separation performance of the CA-Cu-BTC/Pebax MMMs at 25℃under humid condition was examined.The results show that,compared to the pure Pebax membrane,the prepared MMMs show improved CO_(2)permeability and CO_(2)/N_(2)selectivity,with an optimized CO_(2)permeability of 837.2 GPU accompanied by the CO_(2)/N_(2)selectivity of 49.1.Besides,the high water stability of the filler originated from CA functionalization endows the prepared MMMs with potential for application in practical industrial gas separations.