ZIF-8/PSF复合膜的制备及其CO_(2)分离性能研究

Study on preparation of ZIF-8/PSF composite membrane and its CO_(2) separation performance

由无机填料和有机基质组成的混合基质膜(MMMs)被广泛认为在CO_(2)分离中发挥着重要作用.本研究开发了一种逐层复合工艺,即通过浸涂-热转换制备与载体结合强度高的ZIF-8薄膜层,而后涂覆PSF聚合物溶液使其与ZIF-8膜层紧密结合得到ZIF-8/PSF混合基质复合膜.ZIF-8/PSF复合膜展现出CO_(2)优先渗透性能,对于等摩尔CO_(2)/CH_(4)混合气分离,CO_(2)渗透率为1.5×10^(-8)mol/(m^(2)·s·Pa),CO_(2)/CH_(4)的选择性为39.此外,ZIF-8/PSF复合膜具有优异的耐温性、耐压性、以及长周期稳定性.

Mixed matrix membranes(MMMs),composed of inorganic fillers and organic substrates,are widely believed to play an important role in CO_(2) separation.In this study,a layer-by-layer composite technology was developed,that is,the ZIF-8 layer with high adhesive strength to the porous support was prepared by the dip coating and thermal conversion method,and then the ZIF-8/PSF mixed matrix composite membrane was achieved by coating PSF polymer solution on the ZIF-8 layer.Due to the excellent interfacial bonding strength between the membrane matrix and the coating layer,the ZIF-8/PSF composite membrane showed CO_(2)-preferred permeability.For equimolar CO_(2)/CH_(4) mixture separation,the CO_(2) permeance was 1.5×10^(-8)mol/(m^(2)·s·Pa)and the selectivity of CO_(2)/CH_(4) was 39.In addition,the ZIF-8/PSF membrane exhibited satisfactory temperature and pressure resistance,and durability.