三氟甲基磺酰氟的过热分解产物规律与成因分析

doi:10.19595/j.cnki.1000-6753.tces.251460

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Abstract The chemical stability and decomposition characteristics of SF₆ alternative gases play a crucial role in determining the insulation performance and operational safety of environmentally friendly gas-insulated electrical equipment. Among the potential substitutes, trifluoromethanesulfonyl fluoride (CF₃SO₂F) has attracted increasing attention due to its excellent dielectric properties and low global warming potential (GWP). However, its thermal stability under overheating conditions has not been systematically studied, and a clear understanding of its decomposition behavior is essential for its reliable application in power equipment.
To clarify its decomposition mechanism and major gaseous products, a series of overheating defect simulation experiments were conducted under controlled temperature conditions. The chamber was cleaned and evacuated to remove residual moisture and oxygen, then charged with CF₃SO₂F at a preset pressure and heated stepwise from 120℃ to 400℃ to simulate localized overheating. The decomposition products were identified and quantified using gas chromatography-mass spectrometry (GC-MS), and their temperature-dependent concentration trends were analyzed, providing key insights into the decomposition pathways of CF₃SO₂F.
Experimental results show that CF₃SO₂F remains thermally stable below approximately 250℃ but begins to gradually decompose as the temperature increases beyond this threshold. At 400°C, CF₃SO₂F is almost completely decomposed, and the dominant products are CF₄, C₂F₆, C₃F₈, SO₂, SO₂F₂, and SOF₂. Among these species, fluorocarbon products (CF₄, C₂F₆, and C₃F₈) are indicative of the cleavage and recombination of C-F fragments, while sulfur-oxygen products (SO₂, SO₂F₂, and SOF₂) reflect the oxidation and rearrangement processes of the sulfonyl group under high-temperature conditions. The formation of such products suggests that multiple parallel and consecutive reactions occur during CF₃SO₂F decomposition, governed by both thermal activation and radical recombination mechanisms.
To further elucidate the molecular-level mechanisms, comprehensive quantum chemical calculations were performed at the M06-2X/aug-cc-pVTZ level combined with single-point energy refinement at the CBS-QB3 level for improved energetic accuracy. Several plausible decomposition and product formation pathways were proposed and characterized by geometry optimization, transition state search, and intrinsic reaction coordinate (IRC) analysis. The computed thermodynamic parameters, including enthalpy (ΔH) and Gibbs free energy changes (ΔG), were used to assess the feasibility and spontaneity of each pathway. Results show that the C-S bond cleavage pathway possesses the lowest energy barrier, confirming it as the primary decomposition route of CF₃SO₂F. Subsequent radical recombination reactions lead to the generation of CF? and longer-chain perfluorocarbons (C₂F₆ and C₃F₈), with increasing synthetic difficulty following the order CF₄<C₂F₆<C₃F₈. Meanwhile, the formation of sulfur-oxygen species is mainly attributed to rearrangement and oxidation reactions involving SO₂F and SOF intermediates under elevated temperature conditions.
Overall, the combination of experimental and theoretical results provides a comprehensive understanding of the thermal decomposition mechanism of CF₃SO₂F. The findings indicate that although CF₃SO₂F exhibits good thermal stability under moderate conditions, it undergoes significant decomposition under severe overheating, producing fluorocarbons and sulfur oxides that may influence insulation performance and environmental safety. The established decomposition pathways and thermodynamic data offer valuable theoretical and experimental guidance for assessing the stability, safety, and engineering applicability of CF₃SO₂F as a potential alternative to SF₆ in gas-insulated electrical equipment.

Key words： Trifluoromethanesulfonyl fluoride overheating gas chromatography-mass spectrometry decomposition characteristics quantum chemistry calculation

Received: 21 August 2025

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	Shen Sijie
	Gao Keli
	Yan Xianglian
	Duan Junran
	Zhang Guoqiang
	Han Dong

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Shen Sijie,Gao Keli,Yan Xianglian等. Thermal Decomposition Behavior and By-Product Formation Mechanism of Trifluoromethanesulfonyl Fluoride[J]. Transactions of China Electrotechnical Society, 2026, 41(15): 5285-5295.

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https://dgjsxb.ces-transaction.com/EN/10.19595/j.cnki.1000-6753.tces.251460 OR https://dgjsxb.ces-transaction.com/EN/Y2026/V41/I15/5285

[1] IPCC. Climate Change 2023: Synthesis Report. Contribution of Working Groups I, II and III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change[R]. Geneva: Intergovernmental Panel on Climate Change, 2023.
[2] 张晓星, 肖淞, 张博雅, 等. PFAS及含氟气体管控下环保绝缘气体研究与电力装备应用展望[J]. 中国电机工程学报, 2024, 44(1): 362-376, I0030.
Zhang Xiaoxing, Xiao Song, Zhang Boya, et al.Challenges and prospects for the research of environmentally friendly insulating gases and applications of power equipment under control policies of PFAS and fluorine gas[J]. Proceedings of the CSEE, 2024, 44(1): 362-376, I0030.
[3] 崔兆仑, 郝艳捧, 阳林, 等. SF₆废气无害化降解研究综述[J]. 中国电机工程学报, 2023, 43(19): 7720-7736.
Cui Zhaolun, Hao Yanpeng, Yang Lin, et al.Review on harmless abatement of SF₆ waste gas[J]. Proceedings of the CSEE, 2023, 43(19): 7720-7736.
[4] International Energy Agency.SF₆ emissions in energy sector 2022[R]. Paris: IEA, 2022: 15-18.
[5] Sovacool B K, Griffiths S, Kim J, et al.Climate change and industrial F-gases: a critical and systematic review of developments, sociotechnical systems and policy options for reducing synthetic greenhouse gas emissions[J]. Renewable and Sustainable Energy Reviews, 2021, 141: 110759.
[6] 周朕蕊, 韩冬, 赵明月, 等. SF₆替代气体分解特性的研究综述[J]. 电工技术学报, 2020, 35(23): 4998-5014.
Zhou Zhenrui, Han Dong, Zhao Mingyue, et al.Review on decomposition characteristics of SF₆ alternative gases[J]. Transactions of China Electro-technical Society, 2020, 35(23): 4998-5014.
[7] 高克利, 杨圆, 周文俊, 等. SF₆替代型环保绝缘气体: 研究、应用和展望[J]. 中国电机工程学报, 2024, 44(18): 7395-7411.
Gao Keli, Yang Yuan, Zhou Wenjun, et al.SF₆ alternative environmentally friendly insulating gas: research, application and outlook[J]. Proceedings of the CSEE, 2024, 44(18): 7395-7411.
[8] 颜湘莲, 高克利, 郑宇, 等. SF₆混合气体及替代气体研究进展[J]. 电网技术, 2018, 42(6): 1837-1844.
Yan Xianglian, Gao Keli, Zheng Yu, et al.Progress of gas mixture and alternative gas of SF₆[J]. Power System Technology, 2018, 42(6): 1837-1844.
[9] Yu Xiaojuan, Hou Hua, Wang Baoshan.A priori theoretical model for discovery of environmentally sustainable perfluorinated compounds[J]. The Journal of Physical Chemistry A, 2018, 122(13): 3462-3469.
[10] Wootton R E, Murrysville P. Dielectric gas mixture containing trifluoronitro-methane and/or trifluorome-thanesulfonyl fluoride: US4275260A[P].1981-06-23.
[11] Niemeyer L.A systematic search for insulation gases and their environmental evaluation[M]//Christophorou L G, Olthoff J K. Gaseous Dielectrics VIII. Boston, MA: Springer US, 1998: 459-464.
[12] Long Yunxiang, Guo Liping, Wang Yi, et al.Electron swarms parameters in CF₃SO₂F as an alternative gas to SF₆[J]. Industrial & Engineering Chemistry Research, 2020, 59(24): 11355-11358.
[13] 罗建志, 王少波, 李绍波, 等. 三氟甲基磺酰氟的合成及应用研究进展[J]. 化学工程与装备, 2010(2): 121-124.
Luo Jianzhi, Wang Shaobo, Li Shaobo, et al.Progress in synthesis and application of trifluoromethylsulfonyl fluoride[J]. Chemical Engineering & Equipment, 2010(2): 121-124.
[14] Wang Yi, Gao Zhanyang, Wang Baoshan, et al.Synthesis and dielectric properties of trifluorome-thanesulfonyl fluoride: an alternative gas to SF₆[J]. Industrial & Engineering Chemistry Research, 2019, 58(48): 21913-21920.
[15] Hu Shizhuo, Wang Yi, Zhou Wenjun, et al.Dielectric properties of CF₃SO₂F/N₂ and CF₃SO₂F/CO₂ mixtures as a substitute to SF₆[J]. Industrial & Engineering Chemistry Research, 2020, 59(35): 15796-15804.
[16] 胡世卓, 周文俊, 罗赟, 等. 不均匀电场下CF₃SO₂F混合气体的工频击穿特性[J]. 绝缘材料, 2023, 56(12): 128-135.
Hu Shizhuo, Zhou Wenjun, Luo Yun, et al.Power frequency breakdown characteristics of CF₃SO₂F mixtures under non-uniform electric field[J]. Insulating Materials, 2023, 56(12): 128-135.
[17] 逯思敏, 汤贝贝, 高克利, 等. 电晕放电下三氟甲基磺酰氟的分解特性与成因分析[J]. 高电压技术, 2023, 49(11): 4556-4562.
Lu Simin, Tang Beibei, Gao Keli, et al.Decomposition characteristics and by-product formation of trifluoromethyl sulfonyl fluoride under corona discharge[J]. High Voltage Engineering, 2023, 49(11): 4556-4562.
[18] 郑宇, 郝东昕, 刘伟, 等. CF₃SO₂F三元混合气体的工频击穿特性研究[J]. 中国电机工程学报, 2026, 46(1): 424-434.
Zheng Yu, Hao Dongxin, Liu Wei, et al.Power frequency breakdown characteristics of CF₃SO₂F ternary mixed gas[J]. Proceedings of the CSEE, 2026, 46(1): 424-434.
[19] 吕浥尘, 郑宇, 朱太云, 等. 五种吸附剂与C₄F₇N气体及CF₃SO₂F气体的相容性试验研究[J]. 电工技术学报, 2023, 38(增刊1): 196-203.
Lü Yichen, Zheng Yu, Zhu Taiyun, et al.Experimental study on compatibility with C₄F₇N and CF₃SO₂F gases and five adsorbents[J]. Transactions of China Electrotechnical Society, 2023, 38(S1): 196-203.
[20] 万旭昊, 郭宇铮, 高克利, 等. 基于第一性原理的新型环保绝缘介质CF₃SO₂F相容性评估[J]. 高电压技术, 2023, 49(7): 2848-2857.
Wan Xuhao, Guo Yuzheng, Gao Keli, et al.Compatibility evaluation of new eco-friendly insulation medium CF₃SO₂F based on the first-principles[J]. High Voltage Engineering, 2023, 49(7): 2848-2857.
[21] 陈兴发, 郑宇, 任书波, 等. CF₃SO₂F气体与Al(111)表面相容性及其分解特性模拟[J]. 绝缘材料, 2025, 58(2): 66-75.
Chen Xingfa, Zheng Yu, Ren Shubo, et al.Study on compatibility between CF₃SO₂F gas and Al(111) surface and its decomposition characteristics[J]. Insulating Materials, 2025, 58(2): 66-75.
[22] Zhang Mi, Hou Hua, Wang Baoshan.Mechanistic and kinetic investigations on decomposition of trifluoro-methanesulfonyl fluoride in the presence of water vapor and electric field[J]. The Journal of Physical Chemistry A, 2023, 127(3): 671-684.
[23] 张咪, 田亚锋, 高克利, 等. 三氟甲基磺酰氟绝缘介质理化特性的分子动力学模拟[J]. 高等学校化学学报, 2022, 43(11): 145-154.
Zhang Mi, Tian Yafeng, Gao Keli, et al.Molecular dynamics simulation of the physicochemical properties of trifluoromethanesulfonyl fluoride dielectrics[J]. Chemical Journal of Chinese Universities, 2022, 43(11): 145-154.
[24] 徐锋, 代现跃, 李志永, 等. 1种三氟甲基磺酰氟合成新方法[J]. 化工生产与技术, 2022, 28(6): 17-19, I0003.
Xu Feng, Dai Xianyue, Li Zhiyong, et al.A new method for the synthesis of trifluoromethyl sulfonyl fluoride[J]. Chemical Production and Technology, 2022, 28(6): 17-19, I0003.
[25] 刘伟, 韩冬, 朱姗, 等. 典型放电缺陷下的C₄F₇N/CO₂分解特性[J]. 高电压技术, 2023, 49(11): 4498-4506.
Liu Wei, Han Dong, Zhu Shan, et al.Decomposition characteristics of C₄F₇N/CO₂ under typical discharge defects[J]. High Voltage Engineering, 2023, 49(11): 4498-4506.
[26] Siller C W.Carbon disulfide from sulfur dioxide and anthracite[J]. Industrial & Engineering Chemistry, 1948, 40(7): 1227-1233.
[27] Zeng Zhe, Altarawneh M, Dlugogorski B Z.Atmospheric oxidation of carbon disulfide (CS₂)[J]. Chemical Physics Letters, 2017, 669: 43-48.
[28] Feng Tai, Zhou Ping, Zhao Xiqiang, et al.Sulfur evolution reaction during reduction of SO₂ with CO over carbon materials[J]. Energy & Fuels, 2019, 33(8): 7491-7499.
[29] Wojtowicz J A, Hallett L, Miller R R.Toxicology of sulfuryl fluoride[J]. Journal of Toxicology and Environmental Health, 1987, 20(3): 241-250.
[30] Dennis W H, Hille R, Vogin E E.Acute toxicity of sulfur oxyfluorides in rats[J]. Toxicology and Applied Pharmacology, 1979, 48(2): 189-197.
[31] Frisch M J, Trucks G W, Schlegel H B, et al.Gaussian 09, Revision A.01[CP]. Wallingford CT: Gaussian, Inc., 2009.
[32] Lu Tian, Chen Qinxue.Shermo: a general code for calculating molecular thermochemistry properties[J]. Computational and Theoretical Chemistry, 2021, 1200: 113249.