Synthesis of robust interface-anchored composite PVA/PSU/epoxy membrane for highly efficient pervaporation in concentrated brine desalination

Abstract

This study investigates the enhancement of peel-off resistance in polysulfone (PSU) membranes through the incorporation of bisphenol-A. The modified membranes were fabricated and characterized to evaluate their performance compared to conventional PSU membranes. Enhancing the interlayer adhesion within the composite membrane stands as a pivotal factor for ensuring its stable operation. Through meticulous characterization of the PSU structure and surface properties, our findings underscore the significant enhancement in interlayer adhesion facilitated by the introduction of bisphenol-A. In addition, we demonstrate the synergistic effects of PVP and SPSF additives in enhancing the hydrophilic nature of PSU membranes and the development of a novel active layer for membranes by incorporating 1.5 wt% polyvinyl alcohol with P(SS-MA) crosslinker on a PSU supporting layer. The synergistic effects of PVA and P(SS-MA) crosslinker contribute to improved salt rejection while maintaining structural integrity. Operating at a temperature of 70 ℃ and with a 3.5 wt% NaCl aqueous solution, the 16:1 membrane coated with a PVA/P(SS-MA) coating layer exhibited a remarkable flux of 53.6 ± 9.8 kg m−2 h−1. Moreover, treating a highly concentrated solution of 10 wt% at the same temperature yielded a high flux of 38.73 ± 7.4 kg m−2 h−1. Our findings underscore the potential of bisphenol-A modified PSU membranes as promising candidates for applications where strong adhesion and durability are paramount.