Preparation of Co₃O₄@carbon nanotubes modified ceramic membrane for simultaneous catalytic oxidation and filtration of secondary effluent

To improve the efficiency of wastewater reclamation, a novel Co₃O₄@carbon nanotubes modified ceramic membrane (Co₃O₄@CNT-CM) was prepared in this work for simultaneous catalytic peroxymonosulfate (PMS) oxidation and filtration of secondary effluent. The synthesized Co₃O₄@CNT catalyst showed better dispersibility with more active sites exposed, and Co₃O₄@CNT-CM exhibited relatively smooth surface, higher permeate flux and excellent catalytic PMS ability. The antifouling and water purification performance of Co₃O₄@CNT-CM were systematically investigated in secondary effluent purification. With the dual effect of catalytic oxidation and filtration, the organic pollutants were observably reduced. Fluorescent components were also significantly removed, and more macromolecular substances were degraded into small molecular substances. The flux of Co₃O₄@CNT-CM was significantly improved, with the reversible and irreversible resistances decreased by 82.5% and 78.6%, individually. With respect to the fouling mechanism, the volume entering the stage of cake filtration dramatically increased. The prepared Co₃O₄@CNT-CM accelerated the generation of various active species for oxidative degradation of pollutants, thus improving the antifouling performance of membrane. These results demonstrated the application potential of Co₃O₄@CNT-CM for wastewater treatment and reclamation.