Degradation of emerging pollutants present in aqueous effluents using ferrite type catalysts

Abstract

Oxides like ferrites were sintetizated by Pechini method modificated. Four series were obtained, one for each metal: Co, Cu, Zn y Ni varying the calcination temperature (600°C, 800°C and 1000°C).
The structures were characterized by X ray diffraction and scanning electron microscopy. The band gap energy was calculated by the Uv-vis spectra with diffuse reflectance. Except the highest calcined temperature Zn ferrite, may be
possible to activate the samples with visible light in photocatalytic processes due to their band gap energy are low than 3 eV. Magnetic properties were evaluated by vibrant sample magnetometer. If the calcination temperature
increases, the magnetic saturation increases in Cu ferrites. Although, in Co, Ni and Zn ferrites its decreases. The coercivity in Co and Cu ferrites decreases as the calcination temperature increases while in Zn ferrites increases. Ni ferrites do not show significant variations they could be in a superparamagnetic state. Co and Zn ferrites calcined at 800°C were evaluated as a catalyst in Photo-Fenton heterogeneous process to sodium diclofenac degradation. Both materials degraded 100% of pollutant in first 15 minutes of the photoreaction using Uvgermicide lamp and H2O2. Co ferrite mineralised the 86% of total organic carbon in 4 hours of photoreaction.