Preparation, characterization and performance of poly(aylene ether sulfone)/modified silica nanocomposite reverse osmosis membrane for seawater desalination

In this paper, composite reverse osmosis (RO) membranes made from sulfonated poly(arylene ether sulfone) containing amino groups (aPES) and hyper-branched aromatic polyamide-grafted silica (HBP-g-silica) were prepared, with the aim of enhancing chlorination resistance and improving membrane performance. The performance of the RO membranes containing aPES and HBP-g-silica was evaluated; the salt rejection and water flux were 96% and 34 L/m2/h, respectively. After the chlorination test, the salt rejection decreased by only 14% and the water flux increased by 4 L/m2/h. The aPES/HBP-g-silica significantly modified the three-dimensional polyamide (PA) network structures and contributed to the high performance because of the chain stiffness of the copolymer with a high degree of cross-linking in the RO membranes. Therefore, the aPES and HBP-g-silica, which helped improve water permeability, also protected the active layer structure from degradation and enhanced the chlorine resistance of the RO membrane.