Exploring of novel reverse thermally induced phase separation process based on preparation and characterization of polysulfate ultrafiltration membranes with bicontinuous structure

Abstract

Contaminated water sources from various industries pose severe environmental challenges due to their complex compositions, high toxicity, and fluctuating qualities. This study introduces a groundbreaking strategy for fabricating advanced polysulfate (PSE) ultrafiltration membranes using a novel reverse thermally induced phase separation (RTIPS) process. By manipulating the cloud point through the DMAc/DEG solvent/nonsolvent system, our work innovatively controls membrane microstructure, overcoming limitations of conventional nonsolvent-induced phase separation (NIPS). Our findings reveal that RTIPS, when employed above the cloud point, yields PSE membranes with a unique bicontinuous sponge-like structure, significantly improving upon conventional NIPS products. Specifically, the optimized RTIPS membranes exhibit enhanced pure water flux (916.23 vs. 336.23 LMH), larger pore sizes (0.083 vs. 0.054 μm), increased tensile strength (1.32 vs. 0.84 MPa), and improved fouling resistance (FRR 65.5% vs. 55.2%). This research pioneers a facile yet potent method for tailoring membrane properties, achieving a balance between permeability, mechanical stability, and filtration efficacy. The demonstrated success of RTIPS in enhancing PSE membrane performance not only contributes to the development of high-performance water treatment technologies but also charts a new course in membrane science, offering a promising avenue for sustainable wastewater management solutions.