Surface-functionalized PVDF membranes by facile synthetic Cu-MOF-74 for enhanced contaminant degradation and antifouling performance

Catalytic membrane reactors (CMR) based on the sulfate-based advanced oxidation processes (SR-AOPs) have exhibited fantastic applications prospects in water treatment. We synthesized Cu-MOF-74 by an environmentally friendly and facile method, then used it as PVDF (polyvinylidene fluoride) membrane surface modification layer. The results presented that Cu-MOF-74 can significantly improve anti-fouling ability of PVDF membrane (60.9% and 64.1% anti-adsorption of dye and protein). The modified membranes exhibited relatively low flux loss. Simultaneously the modified membrane catalyzed peroxymonosulfate (PMS) to achieve 97.1% degradation efficiency of Rhodamine B (RhB) within 60 min and 90.2% dye penetration recovery within 30 min. Cu-MOF-74 exhibited greater catalytic activity than homogeneous Cu (II) and showed a wide range of pH adaptation. Finally, XPS and ESR proved that it was the redox of Cu (II)/Cu (I) in the Cu-MOF-74 structure making PMS mainly produce SO4-center dot and center dot OH to oxidize pollutant molecules. The modus proposed in this study may provide a more promising strategy for the preparation of high-efficiency catalytic membranes and their practical applications in wastewater treatment processes.

Automated summary

Catalytic membrane reactors based on the sulfate-based advanced oxidation processes have great potential in water treatment. In this study, Cu-MOF-74 was synthesized and used as a surface modification layer for PVDF membranes. The modified membranes showed improved anti-fouling ability and catalytic activity, achieving high degradation efficiency of dye.