Abstract: Apparatus is disclosed for the carrying out of gaseous phase reactions, illustrated by way of example by the preparation of sulphur hexafluoride of high purity, starting from elemental fluorine and sulphur, both in gaseous phase. One of the gaseous reactants, e.g., the fluorine, is fed into a reaction chamber through inlets in a metal plate, maintained at between 30.degree. and 70.degree. C. while the other, e.g., sulphur in gaseous phase, is fed in through the nozzle of a burner, e.g., by regulating a current of an inert gas which is saturated with sulphur by passing same through a zone containing molten sulphur at a temperature between 250.degree. and 500.degree. C., and subsequently superheating the inert gas thus saturated with sulphur to a temperature between 300.degree. and 550.degree. C.

Abstract: Process and apparatus are disclosed for the preparation of sulphur hexafluoride of high purity, starting from elemental fluorine and sulphur, both in gaseous phase, and operating with an excess of fluorine, characterized in that the fluorine is fed into a reaction chamber through inlets in a metal plate, maintained at between 30.degree. and 70.degree. C., while the sulphur is fed in through the nozzle of a burner, by regulating a current of an inert gas which is saturated with sulphur by passing same through a zone containing molten sulphur at a temperature between 250.degree. and 500.degree. C., and subsequently superheating the inert gas thus saturated with sulphur to a temperature between 300.degree. and 550.degree. C.