1
|
Wang C, Xue S, Xu Y, Li R, Qiu Y, Wang C, Ren LF, Shao J. Novel electrocatalytic capacitive deionization with catalytic electrodes for selective phosphonate degradation: Performance and mechanism. Water Res 2024; 256:121614. [PMID: 38657308 DOI: 10.1016/j.watres.2024.121614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Revised: 04/07/2024] [Accepted: 04/14/2024] [Indexed: 04/26/2024]
Abstract
Phosphonate is becoming a global interest and concern owing to its environment risk and potential value. Degradation of phosphonate into phosphate followed by the recovery is regarded as a promising strategy to control phosphonate pollution, relieve phosphorus crisis, and promote phosphorus cycle. Given these objectives, an anion-membrane-coated-electrode (A-MCE) doped with Fe-Co based carbon catalyst and cation-membrane-coated-electrode (C-MCE) doped with carbon-based catalyst were prepared as catalytic electrodes, and a novel electrocatalytic capacitive deionization (E-CDI) was developed. During charging process, phosphonate was enriched around A-MCE surface based on electrostatic attraction, ligand exchange, and hydrogen bond. Meanwhile, Fe2+ and Co2+ were self-oxidized into Fe3+ and Co3+, forming a complex with enriched phosphonate and enabling an intramolecular electron transfer process for phosphonate degradation. Additionally, benefiting from the stable dissolved oxygen and high oxygen reduction reaction activity of C-MCE, hydrogen peroxide accumulated in E-CDI (158 μM) and thus hydroxyl radicals (·OH) were generated by activation. E-CDI provided an ideal platform for the effective reaction between ·OH and phosphonate, avoiding the loss of ·OH and triggering selective degradation of most phosphonate. After charging for 70 min, approximately 89.9% of phosphonate was degraded into phosphate, and phosphate was subsequently adsorbed by A-MCE. Results also showed that phosphonate degradation was highly dependent on solution pH and voltage, and was insignificantly affected by electrolyte concentration. Compared to traditional advanced oxidation processes, E-CDI exhibited a higher degradation efficiency, lower cost, and less sensitive to co-existed ions in treating simulated wastewaters. Self-enhanced and selective degradation of phosphonate, and in-situ phosphate adsorption were simultaneously achieved for the first time by a E-CDI system, showing high promise in treating organic-containing saline wastewaters.
Collapse
Affiliation(s)
- Chengyi Wang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, 200240, Shanghai, PR China; China Electronics System Engineering NO. 2 Construction Co., Ltd., No. 88 Juqu Road, Wuxi, 214135, Jiangsu, PR China
| | - Siyue Xue
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, 200240, Shanghai, PR China
| | - Yubo Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, 200240, Shanghai, PR China
| | - Ran Li
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, 200240, Shanghai, PR China
| | - Yangbo Qiu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, 200240, Shanghai, PR China
| | - Chao Wang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, 200240, Shanghai, PR China
| | - Long-Fei Ren
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, 200240, Shanghai, PR China.
| | - Jiahui Shao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, 200240, Shanghai, PR China; Institute for Ecological Research and Pollution Control of Plateau Lakes, Yunnan University, No. 2 Cuihu North Road, Kunming, 650504, Yunnan, PR China.
| |
Collapse
|