Highly efficient removal of tetracycline and methyl violet 2B from aqueous solution using the bimetallic FeZn-ZIFs catalyst

Abstract

Residual antibiotics and organic dyes in wastewater have gained the current challenge all over the world because of their toxicity to humans and the environment. In this study, the bimetallic porous FeZn-ZIFs materials were successfully prepared under mild conditions at room temperature and atmospheric pressure and characterized by various techniques. The FeZn-ZIFs were used as a heterogeneous catalyst to remove tetracycline antibiotics (TC) and methyl violet 2B dyes (MV) in an aqueous solution by activating peroxymonosulfate (PMS) and peroxydisulfate (PDS), respectively. The catalytic activity of FeZn-ZIFs towards TC and MV under different oxidant dosages, the catalyst dosage, the initial pollutant concentration, contact time, and reaction temperature were optimized. The results indicated that FeZn-ZIFs was an efficient catalyst for removing TC and MV based on advanced oxidant processes, having a removal capacity of 92% at TC concentration of 50 mg·L-1 and 95% MV concentration of 20 mg·L-1. More importantly, this bimetallic catalyst was identified the superior structural stability when the removal efficiency of TC and MV was maintained at approximately 90% after five cycles. In short, the FeZn-ZIFs and PMS/PDS system exhibited a promising application prospect for antibiotic and dye-containing wastewater treatment.