Hydrolysis-induced polyacrylonitrile membranes with high catalytic activity and self-cleaning properties for antibiotic degradation

Abstract

The immobilization of heterogeneous catalysts on membrane supports can realize highly efficient degradation of organic pollutants to alleviate membrane fouling through in situ catalytic oxidation. In this work, a polyacrylonitrile (PAN)-based catalytic membrane was prepared via a phase inversion method in the presence of core-shell structured perovskite catalysts. Following this, a controlled alkali-induced strategy was employed to simultaneously hydrolyze the –CN groups on the membrane surface and the core-shell structured perovskite catalysts anchored in the membrane matrix. Correspondingly, improved hydrophilicity, permeability, and catalytic efficiency via activating peroxymonosulfate were achieved compared with pristine PAN membrane. Rapid tetracycline (TC) elimination (10 ppm, 500 mL) can be realized (99 % in 30 min) under a flux of 334.5 L/m2h (0.02 MPa). Besides, owing to the intrinsic size sieving of the membrane, favorable TC degradation efficiency can also be accomplished in the presence of humic acid. Furthermore, the accumulation of pollutants on the membrane surface was released owing to the massive generation of sulfate radicals and singlet oxygen, enabling self-cleaning properties. More importantly, the as-prepared catalytic membrane possessed attractive stability with the cobalt leaching below 0.013 mg/L. This work provides a method to synergistically enhance permeability, catalytic activity and anti-fouling performance of the membranes, which shows potential application in wastewater decontamination.