High performance internally pressurized hollow fiber thin-film nanocomposite nanofiltration membrane incorporated with tannic acid functionalized MoS2 nanosheets for wastewater treatment

An internally pressurized hollow fiber thin film nanocomposite (TFN) nanofiltration (NF) membrane with tannic acid (TA) functionalized two dimensional MoS2 (TA-MoS2) nanosheets incorporated in its polyamide layer was fabricated via interfacial polymerization process. The extra-low amount TA-MoS2 nanosheets could effectively regulate the interfacial polymerization process to foster the formation of an ultra-smooth and defect-free separation layer on the internal surface of hollow fiber substrate. In this way, we provided additional transport channel in the separation layer for fast water transmission, and achieved the high selectivity in the separation of dye, sulfate and heavy metal salt. The optimized hollow fiber TFN NF membrane possesses a water permeance of 143 L m−2 h−1 MPa−1. Meanwhile, it has a dye rejection of 97 % for most dyes tested and a Cl− / SO42− selectivity of 67. In addition, its rejection of CuSO4, ZnSO4 and MnSO4 is higher than 90 %. Moreover, it also shows better alkali resistance and chlorine resistance performance. Thus, it shows a broad application prospect in dye, sulfate and heavy metal salts removal from industrial wastewater.