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Luo Y, Khoshyan A, Al Amin M, Nolan A, Robinson F, Fenstermacher J, Niu J, Megharaj M, Naidu R, Fang C. Ultrasound-enhanced Magnéli phase Ti 4O 7 anodic oxidation of per- and polyfluoroalkyl substances (PFAS) towards remediation of aqueous film forming foams (AFFF). THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 862:160836. [PMID: 36521599 DOI: 10.1016/j.scitotenv.2022.160836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 12/05/2022] [Accepted: 12/06/2022] [Indexed: 06/17/2023]
Abstract
Per-and polyfluoroalkyl substances (PFAS) remediation is still a challenge. In this study, we propose a hybrid system that combines electrochemical treatment with ultrasound irradiation, aiming for an enhanced degradation of PFAS. Equipped with a titanium suboxide (Ti4O7) anode, the electrochemical cell is able to remove perfluorooctanoic acid (PFOA) effectively. Under the optimal conditions (50 mA/cm2 current density, 0.15 M Na2SO4 supporting electrolyte, and stainless steel/Ti4O7/stainless steel electrode configuration with a gap of ∼10 mm), the electrochemical process achieves ∼100 % PFOA removal and 43 % defluorination after 6 h. Applying ultrasound irradiation (130 kHz) alone offers a limited PFOA removal, with 33 % PFOA removal and 5.5 % defluorination. When the electrochemical process is combined with ultrasound irradiation, we observe a significant improvement in the remediation performance, with ∼100 % PFOA removal and 63.5 % defluorination, higher than the sum of 48.5 % (43 % achieved by the electrochemical process, plus 5.5 % by the ultrasound irradiation), implying synergistic removal/oxidation effects. The hybrid system also consistently shows the synergistic defluorination during degradation of other PFAS and the PFAS constituents in aqueous film forming foam (AFFF). We attribute the synergistic effect to an activated/cleaned electrode surface, improved mass transfer, and enhanced production of radicals.
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Affiliation(s)
- Yunlong Luo
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW 2308, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW 2308, Australia
| | - Ashkan Khoshyan
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW 2308, Australia
| | - Md Al Amin
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW 2308, Australia
| | - Annette Nolan
- Ramboll Australia, The Junction, NSW 2291, Australia
| | | | | | - Junfeng Niu
- Suzhou institute of North China Electric Power University, Jiangsu 215000, PR China
| | - Mallavarapu Megharaj
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW 2308, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW 2308, Australia
| | - Ravi Naidu
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW 2308, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW 2308, Australia
| | - Cheng Fang
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW 2308, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW 2308, Australia.
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Liu L, Hao S, Liu J, Zhou H, Hu X. Removal of phenol from wastewater by electrochemical bromination in a flow reactor. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:88681-88689. [PMID: 35836049 DOI: 10.1007/s11356-022-22008-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 07/10/2022] [Indexed: 06/15/2023]
Abstract
Electrochemical methods have been widely applied in the treatment of phenol wastewater for the past few years. However, conventional electrochemical advanced oxidation processes (EAOPs) generally encounter the problem of electrode passivation and the energy consumption required for mineralization is high. In this work, we reported the treatment of phenol wastewater by electrochemical bromination method in a flow electrolysis cell. The Ti/Sb-SnO2/PbO2 electrode was prepared and used as anode. The experiments were carried out under different initial pH, KBr concentrations, current densities, and volumetric flow rates. The generated 2,4,6-tribromophenol (TBP) could be easily separated from the electrode surface and electrolyte. The brominated intermediates were identified by GC/MS. The removal efficiencies for phenol and COD were 100% and 82.7%, respectively, under the best operational conditions (current density of 40 mA cm-2, KBr concentration of 0.074 mol L-1, initial pH of 1.0, and volumetric flow rate of 114 mL min-1). Furthermore, our electrochemical bromination method offered a high apparent current efficiency (ACE) of 276.6% and a low energy consumption (EC) of 4.54 × 10-3 kWh gCOD-1 after 40 min of electrolysis time, indicating that this process was suitable for phenol wastewater treatment.
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Affiliation(s)
- Lanshan Liu
- Hubei Key Lab of Electrochemical Power Sources, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China
| | - Siying Hao
- Chibi Research Institute for High-Quality Development, Chibi, 437300, China
| | - Jiamei Liu
- Chibi Research Institute for High-Quality Development, Chibi, 437300, China
| | - He Zhou
- Chibi Research Institute for High-Quality Development, Chibi, 437300, China
| | - Xiaohong Hu
- Hubei Key Lab of Electrochemical Power Sources, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China.
- Engineering Research Center of Organosilicon Compounds & Materials of Ministry of Education, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China.
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Zhang Z, Wang Z, Sun Y, Jiang S, Shi L, Bi Q, Xue J. Preparation of a novel Ni/Sb co-doped Ti/SnO2 electrode with carbon nanotubes as growth template by electrodeposition in a deep eutectic solvent. J Electroanal Chem (Lausanne) 2022. [DOI: 10.1016/j.jelechem.2022.116225] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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