Synthesis of new low-cost organic ultrafiltration membrane made from Polysulfone/Polyetherimide blends and its application for soluble azoic dyes removal

Abstract

This study concerns the synthesis and characterization of a new organic ultrafiltration membrane by phase inversion process based on the physical blends of Polysulfone/Polyetherimide (PS/PEI). The organic membranes we have synthesized are innovative; their first performance is to process soluble azoic dyes. They also have a low preparation cost and easy handling. We varied from 5 to 20 wt.% of PEI compared to the wt.% of PS. The microstructural membrane structure obtained was characterized by Fourier Transform Infrared spectroscopy (FTIR) and by nuclear magnetic resonance spectroscopy (NMR). The measurement of the contact angle characterized the surface properties of the membrane and the morphology was evaluated using the scanning electron microscope (SEM). The prepared membrane was evaluated by ultrafiltration of solutions of acid orange 74 (AO-74) and methyl orange (MO). The effect of adding polyetherimide in addition to the polysulfone increases the retention rate of the two dyes at a pressure of 4 bar. The results of the experimental filtration of the optimized membrane (prepared with 20 wt.% of PEI) have a water permeability of 22.66 L/hm2 bar, a maximum rejection rate of RM20 (AO-74) = 68.5% and RM20 (OM) = 64.7% respectively and a good high dye flow of around 10,08 L/h m2 for orange-74 acid AO-74 and 16,30 L/h m2 for methyl orange (OM).

Keywords

• Organic ultrafiltration membrane
• Phase inversion
• Polysulfone/Polyetherimide
• Azoic dyes
• Acid orange 74
• Rejection rate