Process for fine purification of sulphur hexafluoride from impurities

摘要

The present invention relates to the production of high-purity substances and, more specifically, to a process for a fine purification of sulphur hexafluoride from impurities. The process for a fine purification of sulphur hexafluoride comprises purification of sulphur hexafluoride by crystallization at a speed of displacement of the interphase boundary of from 1 to 50 mm/hr at a temperature of from 222.3 to 217 DEG K.; the liquid-phase concentrate formed during crystallization is subjected to sublimation purification under a pressure of from 210 to 1.3-0.13 KPa. The high-purity sulphur hexafluoride is useful in the high-voltage energetics as an insulation and arc-exctinguishing medium, as well as in electronics, laser engineering, metallurgy and medicine.