Two dimensional sulfonated molybdenum disulfide (S–MoS2) thin-film nanocomposite nanofiltration membrane for selective desalination

Abstract

Nano-fillers will be an attractive strategy to improve salt fractionation of nanofiltration (NF) membrane if the integrity problem of nano-fillers in PA layer is well addressed. In this work, molybdenum disulfide (MoS2) nanosheets sulfonated with 1,3-propane sultone was added to the aqueous phase to participate in the interfacial polymerization reaction and construct a novel thin-film nanocomposite (TFN) nanofiltration membrane. A series of characterization and discussion were carried out on the obtained nanomaterials and membranes. The S–MoS2 nanosheet can be well wrapped by the resulted PA layer, thereby preserving the integrity of the PA skin. Furthermore, The TFN membranes possessed enhanced electronegativity and hydrophilicity and the PA layer became thinner and denser after introducing the sulfonated MoS2 nanosheets (S–MoS2) in the PA matrix. In particular, the optimal S–MoS2 composite membrane exhibits excellent performance, which approximately reach 99% divalent salt (Na2SO4) rejection and 1.4-fold water permeance of the pristine membrane. Overall, this study provided a novel way for separation treatment of hypersaline wastewater.