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Wang S, Yu G, Wang J. Treatment of tributyl phosphate by fenton oxidation: Optimization of parameter, degradation kinetics and pathway. CHEMOSPHERE 2023; 317:137889. [PMID: 36657574 DOI: 10.1016/j.chemosphere.2023.137889] [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: 10/25/2022] [Revised: 01/14/2023] [Accepted: 01/15/2023] [Indexed: 06/17/2023]
Abstract
In nuclear industry, tributyl phosphate (TBP) is used as organic extracting solvent to separate uranium and plutonium. The spent TBP is finally discarded as the radioactive organic waste, which should be treated due to its potential risk. In this study, TBP degradation by Fenton oxidation was investigated in detail, including the optimization of operational conditions, degradation kinetics and degradation products. The optimal conditions for TBP degradation (per 10 ml) by Fenton oxidation was: 95 °C, pH 2, 150 ml 30% H2O2, and 105 ml 0.2 M Fe(II). H2O2 was continuously added with the flow rate of 0.5 ml/min, Fe(II) was intermittently added with the flow rate of 3 ml/10 min. The oil phase volume decreased with time and completely disappeared at the third hour. In contrast, the COD in water phase increased firstly and then decreased. At the end of the experiments, the COD achieved 23.8 g/L. The detection of phosphorus in water phase further confirmed the decomposition of TBP. Mono-butyl phosphate and di-butyl phosphate were identified as the intermediate products of TBP degradation. In addition, other four degradation products with the same m/z of 154 were identified, which may be derived from the hydroxylation of mono-butyl phosphate and di-butyl phosphate. Based on the degradation products, the degradation pathway of TBP was proposed. This study could provide an insight into the TBP degradation by Fenton oxidation, and an potential strategy for treating the spent radioactive organic solvent.
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Affiliation(s)
- Shizong Wang
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing, 100084, China; Energy Science Building, INET, Tsinghua University, Beijing, 100084, China.
| | - Guoce Yu
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing, 100084, China; Energy Science Building, INET, Tsinghua University, Beijing, 100084, China.
| | - Jianlong Wang
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing, 100084, China; Beijing Key Laboratory of Radioactive Wastes Treatment, Tsinghua University, Beijing, 100084, China.
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Mao Y, Zhang W, Li H, Chen Q, Kasomo RM, Luo H, Song S. Utilization of Fenton oxidation approach in wet phosphoric acid process for mitigating foam generation. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.129297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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P VA, Mishra S, Rajeev R, Desigan N, Venkatesan K, Ananthasivan K. Hydrolysis of tri-butyl phosphate in n-dodecane using sodium hydroxide: Factors affecting the hydrolysis process. PROGRESS IN NUCLEAR ENERGY 2022. [DOI: 10.1016/j.pnucene.2022.104247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Yang X, Yu G, Xu L, Wang J. Degradation of the mixed organic solvents of tributyl phosphate and n-dodecane by heterogeneous Fenton-like oxidation using nanoscale zero-valent iron as the catalyst. CHEMOSPHERE 2022; 292:133449. [PMID: 34973247 DOI: 10.1016/j.chemosphere.2021.133449] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 12/08/2021] [Accepted: 12/24/2021] [Indexed: 06/14/2023]
Abstract
The treatment and disposal of spent radioactive organic solvents, i.e., tributyl phosphate (TBP) and diluent (such as kerosene, n-dodecane, etc.), produced in the reprocessing of spent fuel in the closed cycle are crucial for the sustainable development of the nuclear industry. In this study, the synthesized nanoscale zero-valent iron (nZVI) was used as the heterogeneous Fenton-like catalyst to promote the generation of hydroxyl radicals (•OH) by reacting with H2O2 to degrade the mixed organic solvents of TBP and n-dodecane. nZVI was characterized by scanning electron microscopy (SEM), nitrogen adsorption/desorption isotherms, and X-ray photoelectron spectroscopy (XPS) to investigate the micro-morphology, nano-particle size, and surface valence state. The change of Fe2+/Fe3+ concentration ratio during the reaction was measured to clarify the performance of nZVI. The effects of temperature, catalyst dosage, H2O2 dosage, and acidifier concentration on the degradation of TBP and n-dodecane were studied, and the results were complemented by the COD of the aqueous solution and the volume reduction rate of the organic phase. The mixed organic solvents of TBP and n-dodecane containing Co2+ were used to simulate the spent radioactive organic solvents and to study the distribution of nuclides after the reaction. The results showed that most of the radioactivity was in the residual solution, and the condensate contained almost no radioactivity. The degradation of TBP and n-dodecane was carried out separately, which showed that n-dodecane was more difficult to degrade. Density functional theory (DFT) calculations were applied to determine the adsorption energy of organic solvents and nZVI. According to the Fourier transform infrared spectra (FTIR) and their corresponding DFT calculations, liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) of the sample after the reaction, the possible intermediates were analyzed, and the degradation mechanism was speculated.
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Affiliation(s)
- Xingchen Yang
- Department of Nuclear Engineering and Technology, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, 430074, PR China; China-EU Institute for Clean and Renewable Energy, Huazhong University of Science and Technology, Wuhan, 430074, PR China
| | - Guoce Yu
- Institute of Nuclear and New Energy Technology, Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Tsinghua University, Beijing, 100084, PR China; Beijing Key Laboratory of Radioactive Wastes Treatment, Tsinghua University, Beijing, 100084, PR China
| | - Lejin Xu
- Department of Nuclear Engineering and Technology, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, 430074, PR China; China-EU Institute for Clean and Renewable Energy, Huazhong University of Science and Technology, Wuhan, 430074, PR China.
| | - Jianlong Wang
- Institute of Nuclear and New Energy Technology, Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Tsinghua University, Beijing, 100084, PR China; Beijing Key Laboratory of Radioactive Wastes Treatment, Tsinghua University, Beijing, 100084, PR China
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