Sulfate radical-mediated degradation and mineralization of bisphenol F in neutral medium by the novel magnetic Sr2CoFeO6 double perovskite oxide catalyzed peroxymonosulfate: Influence of co-existing chemicals and UV irradiation

Abstract

Metal-based catalysis has notably contributed to the chemical community mainly in environmental science. Various cobalt and iron based catalysts have shown great potential for powerful reactive species. However, the application of cobalt and iron based perovskite for aqueous phase oxidation still remains limited. In this study, Sr2FeCoO6 double perovskite oxide was synthesized and used for the first time as an effective heterogeneous magnetic catalyst for peroxymonosulfate activation to produce free reactive radicals. Bisphenol F (BPF), a new emergent compound, was used as a target contaminant to evaluate the performance of this combination.Sr2FeCoO6 exhibited superior catalytic performance to the single SrFeO3 and SrCoO3 nanocrystals. A synergetic catalytic effect was found between Co and Fe, probably due to the accelerated reduction of Fe. BPF removal depends on catalyst loading, temperature, BPF and PMS concentration. It was observed that Sr2FeCoO6 activates peroxymonosulfate heterogeneously, with its heterogeneity being more pronounced at neutral pH. Kinetics studies reveal that BPF degradation obeys pseudo First order kinetic with an activation energy of 14.085 KJ/mol and an apparent rate constant of 0.026 min−1. Under conditions of 0.45 g L−1 and 10−4 M PMS, the complete BPF degradation occurred within 90 min at neutral conditions. In addition, the degraded BPF had undergone more than 65% mineralization within 6 h. The combination of UV irradiation (254 nm) with the Sr2FeCoO6-PMS system induces a potential acceleration in the mineralization rate. The effects of humic acid, carbonate, bicarbonate and chloride were also evaluated. A total of 8 products were detected, and the associated degradation pathway was proposed. To identify the dominating reactive species generated in the Sr2CoFeO6/PMS system, radical quenching tests and in situ electron paramagnetic resonance analysis were performed. To our knowledge, this is the first study that documents the heterogeneous activation of peroxymonosulfate with cobalt-iron based double perovskite for the treatment of the new emergent compound Bisphenol F.