- Thesis topic: Synergy of Fouling Degradation and Improved Filtration Performance of MnO2@CeO2/PVA/PVDF Membranes Using Advanced Oxidation

- Doi: 

- Abstract: 

        Membrane fouling is an inevitable phenomenon that happens in the long-term operation of the membrane. It can increase operation and maintenance costs; however, there are numerous studies that focus on optimizing membrane antifouling performance. Incorporating with metal oxides is one of the advanced solutions to cope with membrane fouling.
Therefore, this study explores the catalytic performance of MnO2@CeO2 composites for dye degradation and membrane antifouling enhancement. Among a wide range of Mn-to-Ce ratios, 5%MnO2@CeO2 and 15%MnO2@CeO2 catalysts were selected based on their high dye removal efficiencies when combined with peroxymonosulfate (PMS) and further evaluated under various conditions. Various characterization analyses were conducted on these two materials, including Fourier Transform Infrared Spectroscopy (FTIR) to identify functional groups and chemical bonding, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) to examine surface morphology and particle structure, X-ray Diffraction (XRD) to determine crystallinity and phase composition, X-ray Photoelectron Spectroscopy (XPS) to analyze surface chemistry, and Electron Spin Resonance (ESR) to investigate the material's electronic properties.
The 15%MnO2@CeO2 catalyst demonstrated the highest Acid Blue 260 (AB260) removal efficiency of 98%, with a maximum removal capacity of 251.9 mg/g, whereas the 5%MnO2@CeO2 catalyst achieved 87% Acid Yellow 42 (AY42) removal efficiency, with a peak capacity of 77.3 mg/g. 15%MnO2@CeO2 catalyst was selected as the main material to modify the PVDF membrane due to the ability to increase membrane flux and effectively antifouling with PMS. In the characterization, the catalyst has a high oxygen vacancy content when the absorbed oxygen percentage is high in the characterization analysis. Mechanistic investigations identified ¹O2 (singlet oxygen) as the dominant reactive species, while ·OH played a minor role. Additionally, the catalyst dosage equal to 5% of the membrane weight showed 91% AB260 removal, outperforming the pristine membrane (81% removal) while maintaining the highest water flux recovery up to 87% in the membrane bioreactor utilization. This study confirms the high efficiency of MnO2@CeO2 composites in PMS activation, offering potential applications in dye wastewater treatment and membrane fouling control. Future research should focus on catalyst stability, real wastewater application, and cost-effectiveness for large-scale implementation.

Keywords: Antifouling, membrane modification, membrane cleaning, photocatalytic processes, peroxymonosulfate activation, membrane bioreactor.