Ultrafiltration (UF) has been widely used in water and advanced sewage treatment. Unfortunately, membrane fouling is still the main obstacle to further improvement in the system. Fe (III) salt, a type of traditional coagulant, is often applied to mitigate UF membrane fouling. However, low molecule organic weight cannot be effectively removed, thus the water quality after single coagulation treatment does not effectively meet the standard of subsequent water reuse during secondary effluent treatment. Recently, it has been found that potassium ferrate (Fe (VI)) has multiple functions of oxidation, sterilization and coagulation, with other studies proving its good performance in organics removal and membrane fouling mitigation. However, the respective contributions of oxidation and coagulation/adsorption have not yet been fully understood. The oxidation and coagulation/adsorption effects of Fe (VI) during membrane fouling mitigation were investigated here. The oxidation effect of Fe (VI) was the main reason for organics with the MW of 8-20 kDa removal, and its coagulation/adsorption mainly accounted for the smaller amounts of molecular organics removed. The oxidation of Fe (VI) was the main method for overcoming membrane fouling in the initial filtration; it largely alleviated the standard blockage. The formation of a cake layer transformed the main membrane fouling alleviation mechanism from oxidation to coagulation/adsorption and further removed smaller amounts of molecule organics with the increase of filtration cycles and Fe (VI) dosages. The main fouling mechanism altered from standard blocking and cake filtration to only cake filtration after Fe (VI) treatment. Overall, the mechanism of the oxidation and coagulation/adsorption of Fe (VI) were differentiated, and would provide a reference for future Fe (VI) pretreatment in UF membrane fouling control during water and wastewater treatments.
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http://dx.doi.org/10.1016/j.scitotenv.2022.157986 | DOI Listing |
ACS Appl Mater Interfaces
January 2025
Tianjin Key Laboratory for Marine Environmental Research and Service, School of Marine Science and Technology, Tianjin University, Tianjin 300072, China.
Marine biofouling and corrosion have become the main problems affecting the development of the marine industry. Silicone-based coatings have been widely used for antifouling and anticorrosion due to their low surface energy. However, the poor adhesion and low mechanical stability of these materials limit their application in complex marine environments.
View Article and Find Full Text PDFEnviron Res
January 2025
School of Civil Engineering and Architecture, University of Jinan, No. 336 Nanxinzhuang West Road, Jinan, 250022, Shandong Province, PR China. Electronic address:
Membrane bioreactors (MBRs) can effectively remove microplastics (MPs) because of their good rejection performance. However, the influence of MP concentration and particle size on the short-term and long-term operation efficiency of MBRs remains unclear. To address this issue, this study investigated the effects of short-term stress and long-term accumulation of polypropylene microplastics (PP-MPs) with different particle sizes on the operational efficiency of MBRs by running three MBR systems at four concentration stages.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, PR China. Electronic address:
Groundwater is widely threatened by hazardous manganese and ammonia. In present study, a novel gravity-driven fixed-bed ceramic membrane filtration (GDFBCM) with critical PAC-MnOx-ceramsite filters was built to address these issues. Static ceramsite filters in GDCM significantly increased membrane flux from 11 L/m·h to 18 L/m·h on the 50th day of filtration.
View Article and Find Full Text PDFMar Pollut Bull
January 2025
Department of Materials Science and Engineering, Dalian Maritime University, Dalian 116026, PR China; Dalian Key Laboratory of Internal Combustion Engine Tribology and Reliability Engineering, Dalian 116026, PR China. Electronic address:
As a global challenge, marine biofouling is causing serious economic losses and adverse ecological impacts. In recent years, a variety of promising and environmentally friendly anti-fouling strategies have emerged, among which the excellent anti-fouling performance of bionic autocrine coatings has been recognized. However, bionic autocrine coatings still suffer from uncontrollable secretion behavior, poor mechanical stability, and poor abrasion resistance.
View Article and Find Full Text PDFSci Total Environ
January 2025
Center for Water Research, Advanced Institute of Natural Sciences, Beijing Normal University, 519087 Zhuhai, China.
The new EU Urban Wastewater Treatment Directive requires stricter limits introducing quaternary treatments and poses significant challenges to achieving a sustainable environment. Advanced membrane-based treatment processes combined with mathematical models can be a good solution for facing the challenges above. Most existing literature on membrane filtration models primarily focuses on membrane bioreactors, lacking mechanistic models on ultrafiltration (UF) membranes.
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