Effective separation of dyes/salts by sulfonated covalent organic framework membranes based on phenolamine network conditioning

Abstract

This study developed a modified polyacrylonitrile (PAN) membrane controlled by a phenol–amine network and enhanced with a sulfonated covalent organic framework (SCOF), aimed at improving the efficiency of textile wastewater treatment. Utilizing a phenol–amine network control strategy allows for precise manipulation of interfacial reactions in the synthesis of SCOF, achieving highly uniform modification on the surface of the PAN membrane. This modified membrane demonstrated high rejection of over 98% for various water-soluble dyes, including Alcian blue 8GX, Coomassie Brilliant Blue G250, methyl blue, congo red, and rose bengal, and also exhibited specific selectivity in processing salt-containing wastewater. By adjusting the deposition time of the phenol–amine and the concentration of SCOF monomers, optimal retention performance and permeate flux were achieved, effectively separating dyes and salts. This research provides a new and effective solution for treating textile wastewater, especially in separating and recovering dyes and salts, offering broad application prospects in environmental management and water resource management, and highlighting its significant practical implications.