TY - JOUR
T1 - In-situ graft-polymerization modification of commercial ultrafiltration membranes for long-term fouling resistance in a pilot-scale membrane bioreactor
AU - Straub, Anthony P.
AU - Asa, Eli
AU - Zhang, Wei
AU - Nguyen, Thanh H.
AU - Herzberg, Moshe
N1 - Funding Information:
This work was supported by the German-Israeli Water Technology Cooperation Program, which is funded by the Ministry of Science & Technology of Israel and the Federal Ministry of Education and Research of Germany ( BMBF-MOST , BMBF grant # 02WA1261B , MOST grant # GR-2394 ). We also acknowledge the Swiss National Science Foundation Early Postdoc Mobility Fellowship awarded to A.P.S. and Fulbright Fellowship to T.H.N.
Publisher Copyright:
© 2019 Elsevier B.V.
PY - 2020/2/15
Y1 - 2020/2/15
N2 - Despite significant advances in the design of submerged membrane bioreactors for wastewater treatment, membrane organic- and biofouling remain major obstacles to effective operation, decreasing process performance and membrane lifetime. In this work, we report an improved methodology to minimize fouling in commercial polyvinylidene fluoride (PVDF) ultrafiltration (UF) membranes using redox-initiated copolymer grafting. To effectively bind a copolymer that possesses oppositely charged groups to the surface, we modified the membranes during filtration using positively charged [2-(methacryloyloxy)ethyl]-tri-methylammonium (MOETMA) and negatively charged 3-sulphopropyl methacrylate (SPM) monomers, which provide the polyampholyte coating. The binding of the grafted copolymer was verified using Fourier-transform infrared spectroscopy and contact angle measurements. Bench-scale dynamic fouling experiments were employed to optimize the modification time and verify the effectiveness of the modification in mitigating fouling from soluble microbial products and extracellular polymeric substances extracted from municipal wastewater. After demonstrating fouling resistance at the bench scale, membrane fibers were tested in a custom-made membrane bioreactor treating municipal wastewater. During 22 days of testing, fouling was consistently reduced in the case of modified membranes due to the presence of the polyampholyte copolymer barrier that hinders foulant adsorption. At the end of the testing period, the flux of modified fibers was 123% higher than that of the PVDF control. Overall, this work demonstrates a facile and effective modification technique to reduce fouling in ultrafiltration with proven performance during long-term treatment of municipal wastewater.
AB - Despite significant advances in the design of submerged membrane bioreactors for wastewater treatment, membrane organic- and biofouling remain major obstacles to effective operation, decreasing process performance and membrane lifetime. In this work, we report an improved methodology to minimize fouling in commercial polyvinylidene fluoride (PVDF) ultrafiltration (UF) membranes using redox-initiated copolymer grafting. To effectively bind a copolymer that possesses oppositely charged groups to the surface, we modified the membranes during filtration using positively charged [2-(methacryloyloxy)ethyl]-tri-methylammonium (MOETMA) and negatively charged 3-sulphopropyl methacrylate (SPM) monomers, which provide the polyampholyte coating. The binding of the grafted copolymer was verified using Fourier-transform infrared spectroscopy and contact angle measurements. Bench-scale dynamic fouling experiments were employed to optimize the modification time and verify the effectiveness of the modification in mitigating fouling from soluble microbial products and extracellular polymeric substances extracted from municipal wastewater. After demonstrating fouling resistance at the bench scale, membrane fibers were tested in a custom-made membrane bioreactor treating municipal wastewater. During 22 days of testing, fouling was consistently reduced in the case of modified membranes due to the presence of the polyampholyte copolymer barrier that hinders foulant adsorption. At the end of the testing period, the flux of modified fibers was 123% higher than that of the PVDF control. Overall, this work demonstrates a facile and effective modification technique to reduce fouling in ultrafiltration with proven performance during long-term treatment of municipal wastewater.
KW - Anti-fouling
KW - Membrane bioreactor
KW - Surface modification
KW - Ultrafiltration
KW - Wastewater treatment
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U2 - 10.1016/j.cej.2019.122865
DO - 10.1016/j.cej.2019.122865
M3 - Article
AN - SCOPUS:85072884654
VL - 382
JO - Chemical Engineering Journal
JF - Chemical Engineering Journal
SN - 1385-8947
M1 - 122865
ER -