CoZnFeO4 prepared by waste ferrous sulfate as iron source: synthesis, characterization and photocatalytic degradation of methylene blue.

In this study, a ferrate material with a narrow band gap and rapid electron hole separation ability is synthesized for degrading methylene blue from industrial wastewater. Hard ferrite (CoZnFeO₄) with octahedral structure is synthesized by solid-phase method from waste ferrous sulfate. The structure of the catalyst was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTPR) and scanning electron microscopy (SEM). TPR study showed that the oxidation performance of CoZnFeO₄ is improved with the addition of cobalt. The total organic carbon removal rate of methylene blue over CoZnFeO₄ catalyst is 90% within 60 min. The effects of reaction time, pollutant concentration, catalyst dosage and oxidant concentration on the removal efficiency were optimized. ESI–MS demonstrated the stability of the catalyst for leaching. X-ray diffractometry (XRD) and X-ray energy dispersive spectroscopy (XPS) showed that the catalyst could be reused. These findings provide a low cost and simple strategy for rational design and modulation of catalysts for the industrial degradation of organic pollutants. It not only realizes the use of waste to treat waste, but also accords with the current concept of green chemistry. [ABSTRACT FROM AUTHOR]