High purity sulfur hexafluoride has good electrical insulation performance and excellent arc extinguishing performance, such as circuit breaker, high-voltage transformer, gas sealed combined capacitor, high-voltage transmission line, transformer, etc. Its electric strength is 2.5 times that of nitrogen under the same pressure, its breakdown voltage is 2.5 times that of air, and its arc extinguishing capacity is 100 times that of air. It is a new generation of ultra-high voltage insulating medium material superior to that between air and oil.

High purity sulfur hexafluoride is chemically stable. Slightly soluble in water, alcohol and ether, soluble in potassium hydroxide. It does not react chemically with sodium hydroxide, liquid ammonia, hydrochloric acid and water. It does not react with copper, silver, iron and aluminum in a dry environment below 300 ℃. It has no effect on quartz below 500 ℃. It reacts with metal sodium at 250 ℃ and in liquid ammonia at - 64 ℃. It decomposes when mixed with hydrogen sulfide. At 200 ℃, in the presence of specific metals such as steel and silicon steel, it can promote their slow decomposition.

Around 1940, the US Communist Party used it in the Manhattan Plan. It was commercially available in 1947. At present, high-purity sulfur hexafluoride gas is mainly used in electric power industry. Pure SF6 gas is generally recognized as non-toxic. SF6 will have a small amount of concomitant products in the production process, of which S2F10 is recognized as a highly toxic gas, but it can be completely removed after purification.

Although high purity sulfur hexafluoride is non-toxic, it is necessary to prevent the concentration of SF6 gas from rising to the level of hypoxia in the workplace. The density of SF6 gas is about five times that of air. If SF6 gas leaks, it will be deposited in low-lying places, such as cable trenches. If the concentration is too high, people may suffocate. This situation should be taken into account when designing indoor ventilation devices. SF6 gas can be mixed with air through convection, but the speed is very slow. Once the gas is mixed, it will form a mixture of SF6 and air and will not be separated again.

The content of the article comes from high-purity sulfur hexafluoride: http://www.feiliergas.com