Factorial experimental design of imazalil-containing wastewater to be treated by Fenton-based processes

Abstract

Abstract Fenton-based processes have been studied for the mineralization and detoxification of wastewaters from the postharvest of fruit, which were contaminated with the fungicide imazalil (IMZ). For this purpose, studies were carried out in a simulated agro-industrial wastewater. Statistical design of experiments was used to assess the influence of IMZ, Fe(II) and H2O2 concentration in the efficiency of the process. The most significant factor affecting the process was Fe(II). Higher mineralization was obtained with the photo-Fenton process when compared with the Fenton reaction. The optimized Fe(II) and H2O2 for the mineralization of 50 mg L−1 IMZ were 21.5 and 127.5 mg L−1, respectively. LC/MS/MS was used to identify the main products formed during the reaction and a degradation pathway was proposed. An operational cost of 2.06 €/m3 was estimated for the treatment of 10 m3 wastewater contaminated with IMZ.