Interfacial reactions of catalytic ozone membranes resulting in the release and degradation of irreversible foulants

• DOI: 10.1016/j.watres.2022.119244
• Publication Date: 2022-10-12T13:21:53Z
• Authors: Zilong Song; Yanning Li; Zhenbei Wang; Jingyi Sun; Xiaotong Xu; Zizheng Huangfu; Chen Li; Yuting Zhang; Bingbing Xu; Fei Qi; Amir Ikhlaq; Jolanta Kumirska; Ewa Maria Siedlecka
• Keywords: Membrane Fouling; Biofouling; Degradation; Ceramic membrane; Peroxide

An efficient in-situ self-cleaning catalytic ceramic-membrane tailored with MnO2-Co3O4 nanoparticles (Mn-Co-CM) was fabricated. Density functional theory calculations result substantiated that molecular ozone could be effectively adsorbed by oxygen vacancies (OV) on the Mn-Co-CM surface and then direct activated into a surface-bound atomic oxygen (*Oad) and a peroxide (*O2, ad), ultimately producing ·OH. Mn-Co-CM coupling with ozone efficiently removed foulants from the permeate and the membrane surface simultaneously and leading to in-situ formation of ·OH that changed the nature of the irreversible foulants and ultimately resulted in the rapid release and degradation of humic acid-like substances causing irreversible fouling. However, the commercial CM with ozone mainly removed cake layer fouling including protein-like and fulvic acid-like substances, followed by the slow release and degradation of irreversible foulant, resulting in many humic acid-like substances remain on the membrane surface as irreversible fouling. Based on these, the flux growth rate of Mn-Co-CM was 3.5 times higher than that of CM with ozone. This study provides new insights into the mechanism of in-situ membrane fouling mitigation, when using an efficient catalytic ceramic-membrane. This will facilitate the development of membrane antifouling strategies.