Experimental and theoretical analysis on decomposition and by-product formation process of (CF3)2CFCN mixture
Although sulfur hexafluoride (SF6) is widely used in gas-insulated electrical equipment due to the excellent electrical insulation and arc-interruption behaviors, its strong greenhouse effect with high glow warming potential (GWP) has been driving the research on environmentally friendly gases for S...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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AIP Publishing LLC
2019-10-01
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| Series: | AIP Advances |
| Online Access: | http://dx.doi.org/10.1063/1.5116211 |
| _version_ | 1828839259711209472 |
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| author | Mingyue Zhao Dong Han Zhenrui Zhou Guoqiang Zhang |
| author_facet | Mingyue Zhao Dong Han Zhenrui Zhou Guoqiang Zhang |
| author_sort | Mingyue Zhao |
| collection | DOAJ |
| description | Although sulfur hexafluoride (SF6) is widely used in gas-insulated electrical equipment due to the excellent electrical insulation and arc-interruption behaviors, its strong greenhouse effect with high glow warming potential (GWP) has been driving the research on environmentally friendly gases for SF6 alternatives. Recently, the heptafluoro-isobutyrontrile (CF3)2CFCN (3M NovecTM 4710) is reported to have the potential to replace SF6. The decomposition characteristic of gas insulating medium is one of the basic conditions to measure whether it has the feasibility of replacing SF6. However, the decomposition characteristic of (CF3)2CFCN and the formation mechanism of by-products are still unclear. In this paper, a series of AC corona discharge experiments were performed, and the gas by-products of (CF3)2CFCN mixed with CO2, N2 and air were qualitatively analyzed by gas chromatography mass spectrometry (GC/MS) method, respectively. Then, the decomposition mechanism of (CF3)2CFCN molecule and the formation mechanism of gas by-products were studied via density functional theory (DFT) method. The results show that the major gas by-products are CO, CO2, C2O3F6, CF4, C2F6, C3F6, C3F8, C2F4, (CF3)3CF, CF3CN, C2F5CN and CNCN, in addition to trace amounts of F3CC≡CCF3 and CF3CF=CFCF3. Among the three initial dissociation pathways of (CF3)2CFCN molecule, a C-CF3 bond fission pathway that produces CF3CFCN and CF3 radicals is identified as the thermodynamically favorable channel. The bond energy of C–CF3 bond calculated at M06-2X/def2-QZVP//M06-2X/6-311G(d,p) level is 94.7 kcal/mol. |
| first_indexed | 2024-12-12T19:19:28Z |
| format | Article |
| id | doaj.art-a6911d333d174b06ac70b8c1687461a2 |
| institution | Directory Open Access Journal |
| issn | 2158-3226 |
| language | English |
| last_indexed | 2024-12-12T19:19:28Z |
| publishDate | 2019-10-01 |
| publisher | AIP Publishing LLC |
| record_format | Article |
| series | AIP Advances |
| spelling | doaj.art-a6911d333d174b06ac70b8c1687461a22022-12-22T00:14:39ZengAIP Publishing LLCAIP Advances2158-32262019-10-01910105204105204-1010.1063/1.5116211015910ADVExperimental and theoretical analysis on decomposition and by-product formation process of (CF3)2CFCN mixtureMingyue Zhao0Dong Han1Zhenrui Zhou2Guoqiang Zhang3Institute of Electrical Engineering, Chinese Academy of Sciences, No. 6 Beiertiao, Beijing 100190, P. R. ChinaInstitute of Electrical Engineering, Chinese Academy of Sciences, No. 6 Beiertiao, Beijing 100190, P. R. ChinaInstitute of Electrical Engineering, Chinese Academy of Sciences, No. 6 Beiertiao, Beijing 100190, P. R. ChinaInstitute of Electrical Engineering, Chinese Academy of Sciences, No. 6 Beiertiao, Beijing 100190, P. R. ChinaAlthough sulfur hexafluoride (SF6) is widely used in gas-insulated electrical equipment due to the excellent electrical insulation and arc-interruption behaviors, its strong greenhouse effect with high glow warming potential (GWP) has been driving the research on environmentally friendly gases for SF6 alternatives. Recently, the heptafluoro-isobutyrontrile (CF3)2CFCN (3M NovecTM 4710) is reported to have the potential to replace SF6. The decomposition characteristic of gas insulating medium is one of the basic conditions to measure whether it has the feasibility of replacing SF6. However, the decomposition characteristic of (CF3)2CFCN and the formation mechanism of by-products are still unclear. In this paper, a series of AC corona discharge experiments were performed, and the gas by-products of (CF3)2CFCN mixed with CO2, N2 and air were qualitatively analyzed by gas chromatography mass spectrometry (GC/MS) method, respectively. Then, the decomposition mechanism of (CF3)2CFCN molecule and the formation mechanism of gas by-products were studied via density functional theory (DFT) method. The results show that the major gas by-products are CO, CO2, C2O3F6, CF4, C2F6, C3F6, C3F8, C2F4, (CF3)3CF, CF3CN, C2F5CN and CNCN, in addition to trace amounts of F3CC≡CCF3 and CF3CF=CFCF3. Among the three initial dissociation pathways of (CF3)2CFCN molecule, a C-CF3 bond fission pathway that produces CF3CFCN and CF3 radicals is identified as the thermodynamically favorable channel. The bond energy of C–CF3 bond calculated at M06-2X/def2-QZVP//M06-2X/6-311G(d,p) level is 94.7 kcal/mol.http://dx.doi.org/10.1063/1.5116211 |
| spellingShingle | Mingyue Zhao Dong Han Zhenrui Zhou Guoqiang Zhang Experimental and theoretical analysis on decomposition and by-product formation process of (CF3)2CFCN mixture AIP Advances |
| title | Experimental and theoretical analysis on decomposition and by-product formation process of (CF3)2CFCN mixture |
| title_full | Experimental and theoretical analysis on decomposition and by-product formation process of (CF3)2CFCN mixture |
| title_fullStr | Experimental and theoretical analysis on decomposition and by-product formation process of (CF3)2CFCN mixture |
| title_full_unstemmed | Experimental and theoretical analysis on decomposition and by-product formation process of (CF3)2CFCN mixture |
| title_short | Experimental and theoretical analysis on decomposition and by-product formation process of (CF3)2CFCN mixture |
| title_sort | experimental and theoretical analysis on decomposition and by product formation process of cf3 2cfcn mixture |
| url | http://dx.doi.org/10.1063/1.5116211 |
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