Preparation of Co3O4/PES composite nanofiltration membranes for efficient anti-fouling and dye removal

Abstract

Nanofiltration membranes are nowadays widely being used for dye wastewater treatment. However, the membranes often undergo significant and undesirable fouling during wastewater treatment. Herein, Co₃O₄/PES composite nanofiltration membranes with anti-fouling capability were successfully prepared by loading Co₃O₄ nanocubes into the polyethersulfone (PES) matrix by non-solvent induced phase inversion. Incorporation of Co₃O₄ nanocubes into the PES matrix improved the separation performance and anti-fouling capability of the membranes. The resultant membranes showed a high water flux (176.65 L m⁻² h⁻¹) and excellent rejection for several dyes (Direct red 23, Methyl blue, and Congo red: 65.03–98.9%). Prominently, the optimized Co₃O₄/PES-0.75 composite nanofiltration membrane exhibited a FRR of 83.5%. More significantly, the peroxomonosulfate (PMS) treated nanofiltration composite membrane showed good reusability with a higher FRR (91.5%). The method proposed in the current study may provide a valuable insight for solving membrane fouling problems in the nanofiltration process of organic pollutant separation.