Disinfection through advance oxidation processes: optimization and application on real wastewater matrices

Abstract

Disinfection is an essential and significant process for water treatment to protect the environment and human beings from pathogenic infections. In this study, disinfection through the generation of hydroxyl (Fenton process (FP)) and sulfate (Fenton-like process (FLP)) radicals was validated and optimized. The optimization was carried out in synthetic water through an experimental design methodology using the bacteria Escherichia coli as a model microorganism. Different variables were evaluated in both processes: precursor concentration (peroxymonosulfate (PMS) and H2O2), catalyst concentration (Fe+2), and pH in the Fenton process. After that, the optimized conditions (FP: 132.36 mM H2O2, 0.56 mM Fe+2 and 3.26 pH; FLP: 3.82 mM PMS and 0.40 mM Fe+2) were applied to real matrices from wastewater treatment plants. The obtained results suggest that both processes are promising for disinfection due to the high oxidant power of hydroxyl and sulfate radicals.