Through independent R&D and innovation, Beijing Yuji successfully developed the process for Perfluoroisobutyronitrile (C4F7N). It is an alternative to SF6 for insulating and arc quenching of electrical equipment, which short supply in international and domestic markets. At present, there is no other company in China who can produce this product, and is heavily dependent on imports. The price is high and it is far from meeting the needs of China’s power units, scientific research institutes, and business units. With the breakthrough of various technical difficulties, Beijing Yuji has developed a continuous production process of Perfluoroisobutyronitrile, which is suitable for industry commercial production. The successful development of this process indicates that Beijing Yuji has become the domestic manufacture of pilot scale production of Perfluoroisobutyronitrile, and it also makes China to be one of a few countries that have mastered the preparation technology of Perfluoroisobutyronitrile.
Perfluoroisobutyronitrile, also known as 2,3,3,3-Tetrafluoro-2- (trifluoromethyl)-propanenitrile, molecular formula C4F7N, is a colorless gas at room temperature (25°C, 760 mm Hg), and 3M markets its trade name Novec 4710, which is used as insulating and arc quenching gas in electrical equipment to replace SF6. Based on a mixture of Perfluoroisobutyronitrile (GE’s trade name is g3 gas), it has the following characteristics: excellent insulating performance, excellent arc quenching performance, good materials compatibility in the switch, low toxicity, no flash point in line with health and safety requirements, can be adapted to harsh low-temperature environment requirements, environment-friendly and ODP is zero, GWP (2210) is much lower than SF6 (22800) and the atmospheric residence time is only 1% of SF6.
Due to its high dielectric strength, SF6 gas is widely used in electrical insulation switching equipment in the global electrical industry. At the same time, SF6 is a strong greenhouse gas and has been listed by “Kyoto Protocol” as one of the six restricted greenhouse gases. It is a trend to look for an environment-friendly gas that is comparable to SF6 gas or better to replace SF6. Some artificial dielectric gases, such as N2/SF6 mixture, CF3I, c-C4F8 /CF4, C4F7N, and many other gases were studied by relevant researchers as a feasible gas to replace SF6, Perfluoroisobutyronitrile stands out among them.