Persulfate Activation of Iron-Based Battery Catalytic Material (LFP) Modified on Polymeric Membrane (LFP@PVDF) for the Treatment of Textile Dye Wastewater

In this study, a novel LFP–catalytic microfiltration membrane (LFP@PVDF) was fabricated by loading a lithium-ion battery material LiFePO4 (LFP) onto polymeric micro-porous polyvinylidene fluoride (PVDF) using a filter press coating method. The successful loading of LFP material onto the LFP@PVDF catalytic membrane was confirmed by the characterization of the material using FTIR, SEM, EDX, and XRD analysis. To evaluate the catalytic performance of the LFP@PVDF membrane, the reactive black 5 (RB5) dye-containing solution was used with or without the peroxymonosulfate (PMS) activator in a dead-end filtration under room conditions. The influence of parameters such as LFP loading, initial RB5 dye concentration, persulfate dosage, and solution pH on the performance of the persulfate oxidation process was comprehensively examined. It was found that the LFP@PVDF membrane/persulfate activation system can effectively remove RB5 dye with an efficiency of 97.3%. The RB5 dye removal by LFP@PVDF membranes with varying experimental conditions was found to fit the pseudo-second-order kinetic model. Quenching experiments showed that the reactive species HO•, SO4•− and 1O2 were responsible for the dye removal. The LFP@PVDF membrane/persulfate activation system appeared to be a promising approach for the removal of organic contaminants.