The fluorine-contained gases exemplified by the sulfur hexafluoride and their mixtures are widely used in electrical appliances of power switcher. However, the greenhouse effect of the gas is 23500 times as much as that of carbon dioxide. The total amount of leaked SF6, in the year of 2017, gave rise to the equal effect of 1.3 million automobiles running on the roads within EU, and therefore the gas is listed as a restricted gas in discharge by the United Nations Framework Organization on Climate Change. The researchers constantly put out other fluorine-contained gases with lower effects of greenhouse but cannot resolve the problem of higher coefficient of greenhouses or higher temperature of gases’ liquefication, with the result of not achieving the fundamental “green” switchers. In summary , it is of great importance to achieve the target of reduction of emission in an effort to develop a fluoride-free electricity equipment while the fluorien-contained gases is strictly limited.

 Perfluoroisobutyronitrile, in short form of C4F7N,  CAS No: 42532-60-5, a gas with high volatility can be used as main dielectric component of insulation owing to its good insulation and environmentally friendly properties. Its coefficient of greenhouses (GWP) is only 2210, far lower than that of SF6, suitable to replace the sulfur hexafluoride for the purpose of reducing the greenhouse effect. Nowadays C4F7N gains a greater concern by the electrical industry across the world and is on its way of spreading the application.

 A state owned research institute has undertaken the task of developing the process of C4F7N to an industrialize degree. The institute has accomplished, the design of process, laboratory testing and feasibility study, acquired the process method with the proprietary right with 6 invention approved. In 2019, the institute expanded its pilot scale production, getting access to the industrialized production with all technical obstacles cleared. An authorized test and analysis institute in Shanghai proved the purity of the gas is up to 99.9% plus

 The last test was done and verified by the China High Voltage Testing Centre of Electrical Appliances in 2020, marking the initiating stage of C4F7N’s application in the ultra-high voltage electrical switcher system of 1000 kilovolts with the newest environmental friendly gas in the the world