Fabrication of polyamide thin-film nanocomposite reverse osmosis membrane with improved permeability and antibacterial performances using silver immobilized hollow polymer nanospheres

Thin-film nanocomposite (TFN) membrane with polyamide (PA) layer containing nanofillers have attracted extensive attention due to their excellent properties. In this study, hollow polymer phenolic resin nanospheres (HPS) and silver nanoparticles immobilized HPS (Ag/HPS) were synthesized with 2,4-dihydroxy benzoic acid and hexamethylene tetramine, and used as nanofillers to prepare TFN-HPS and TFN-Ag/HPS membrane. In this paper, the effects of HPS and Ag/HPS addition (0.002 wt%, 0.004 wt%, 0.006 wt%, 0.008 wt% and 0.010 wt%) on TFN membranes separation performance were investigated. The results showed that the water fluxes of TFN-HPS and TFN-Ag/HPS membranes reaches 64.7 L·m−2·h−1 and 64.0 L·m−2·h−1, respectively, when the addition amount of HPS and Ag/HPS was 0.006 wt%, which is about 80 % higher than that of TFC membranes (36.0 L·m−2·h−1). Furthermore, the TFN-HPS and TFN-Ag/HPS membrane have excellent long-term stability. After seven days of continuous operation, the water flux of TFN-HPS and TFN-Ag/HPS membranes remains at 50.0 L·m−2·h−1 and 45.6 L·m−2·h−1, respectively. In addition, the fouling resistance of TFN-HPS and TFN-Ag/HPS membranes is significantly improved, with flux recovery rates reaching 88.8 % and 91.4 %, respectively. Importantly, the sterilization rate of TFN-Ag/HPS membrane containing antibacterial silver to Escherichia coli is up to 96.7 %.