Recyclable ZIF-9@CA-Fe 3 O 4 /RGO/cellulose composite membrane as efficient catalysts for activating peroxymonosulfate to degrade methylene blue

The treatment of dyes in wastewater is important to solve environmental problems. Advanced oxidation processes has been proved to be an effective treatment. In this work, a novel nanocomposite catalyst of ZIF-9@Fe3O4 (cobalt-containing zeolitic imidazolate framework-9 coated Fe3O4 nanocomposite) modified reduced graphite oxide (RGO) was prepared for the first time and coded as ZIF-9@CA-Fe3O4/RGO. Then, ZIF-9@CA-Fe3O4/RGO was immobilized on a cellulose membrane to obtain a composite membrane, which was used as a composite catalyst for activating peroxymonosulfate to degrade methylene blue (MB). The results demonstrated that the composite membrane could efficiently degrade approximately 96% of MB in 9 min without adjusting the initial pH and maintain good catalytic activity even after seven cycles. Furthermore, the composite membrane can be easily separated from the solution at the end of the reaction. This work indicates that the composite membrane has a broad application prospect in industrial applications.