Efficient removal of perfluorooctanoic acid by UV-based peroxide/persulfate advanced oxidation process

Abstract

Abstract Perfluorooctanoic acid (PFOA) challenge traditional aquatic treatment and recycling from recalcitrant organic compounds, which ubiquitously persist in the environment, mainly water bodies, and cause various concerns in human and the environment. Conventional water technology treatment technologies are proven inefficient and must focus on the advanced oxidation processs (AOP). This study conducted treatability studies for removing PFOA using direct photolysis, UV/peroxide, and UV/persulphate oxidation using a lab-scale reactor. The experiment was performed with an initial concentration of 20 mg/L at 120 minutes for a 500 mL sample. The oxidant dosage and pH have been optimized based on the mineralization efficiency. The efficient method for the degradation of PFOA is based on their percentage reduction in concentration, mineralization efficiency, and Reaction kinetics study. It was found that all three processes were adequate for the mineralization of PFOA. Among them, UV/persulphate was more effective in mineralizing PFOA. The TOC removal percentage using direct photolysis, UV/persulphate, and UV/peroxide treatment were 49%, 80%, and 66%, respectively. The pseudo-first-order kinetics for those three were 0.160, 0.489, and 0.349 per hour, respectively.