Persulfate activation for efficient remediation of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) in water: Mechanisms, removal efficiency, and future prospects

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), widely employed as synthetic organic materials in industrial production, have raised significant concerns due to their stability, persistence, and detrimental effects on human health and the environment. In recent years, persulfate has emerged as a promising agent for water treatment, effectively purifying water by generating sulfate radicals (SO4·-) in diverse systems. This comprehensive review investigates the activation mechanisms of persulfate and evaluates the removal efficiency of PFOA and PFOS within the persulfate systems. These systems encompass thermal activation, photoactivation, chemical activation using transition-metal materials and carbonaceous materials, as well as the combining methods. The influence of the coexisting matters (Cl-, NO3-, CO32-/HCO3-) and humic acid is also presented. Additionally, the main degradation mechanisms of PFOA and PFOS are also summarized. Moreover, this review identifies existing limitations and proposes prospects for enhancing the remediation of PFOA and PFOS in water using persulfate. By providing valuable insights, this study serves as a crucial reference for researchers engaged in the remediation of PFOA and PFOS in aquatic environments.