Upgrading the performances of polysulfone/polyetherimide ultrafiltration composite membranes for dyes removal: Experimental and molecular dynamics studies

Organic dye pollutants released by textile industries pose a threat to public health and environmental quality. Hence, a greater emphasis is required for handling these toxic and non-biodegradable effluents. This paper reports on the performance of polysulfone (PSf)/polyetherimide (PEI) ultrafiltration (UF) composite membranes coated on polyester (PE) support by spin/spray-coating technique to remove reactive blue 171 (RB171) and Basic Red 1 (BR1) from water. Prepared composite membranes with polysulfone (PSf) and different PEI loading (25 wt% (CM25), 30 wt% (CM30), and 35 wt% (CM35)) were initially characterized in terms of morphological, mechanical, wetting and water transport properties. Morphological characterization by SEM showed homogeneous and uniform distribution of PSf/PEI membrane layer on the polyester support. Results showed that composite membranes exhibited both enhanced pure water permeability (PWP) and improved dyes removal capacity. The composite membranes CM35 showed a PWP of 77.42 L/hm2bar, and rejection rates of 93.8% and 78.9% for RB171 and BR1, respectively. Molecular dynamics (MD) simulations indicated that simulated membranes hindered the diffusion of dyes inside layers. This study showed that the combination of polyester support and PSf/PEI membrane layers enabled the design of stable and highly efficient filtration membranes.