A critical review of oxidation for membrane fouling control in water treatment: Applications, mechanisms and challenges

Membrane fouling seriously impedes the application of membrane technology in water treatment. Although oxidation achieved intensive attention in membrane fouling control, controversy results were observed in many works since oxidation may accelerate fouling and damage membrane under some circumstances and the underlying mechanism still remained unclear in complex water matrices. This study provides a comprehensive review on the recent progress of pre-oxidation and oxidation cleaning in fouling control for membrane (e.g., microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), reverse osmosis (RO), forward osmosis (FO), membrane distillation (MD)). Common oxidation approaches (e.g., chlorine, ozonation, H₂O₂, sulfate radical (SO₄^●–), potassium permanganate (KMnO₄) and Fe(VI) based oxidation) were systematically summarized and compared, along with their positive and negative impact on fouling mitigation. Furthermore, the fouling control performance and underlying mechanism were reviewed according to the recent published literatures. Ultimately, the challenges and future prospects of oxidation technology in membrane fouling control application were also proposed based on the current review. Overall, this review may provide the guidance for developing advanced oxidation strategy in controlling membrane fouling in water treatment and minimizing the potential drawbacks and risks of oxidation as a membrane fouling control strategy.