Liquid-phase fluorination

A method for producing an essentially perfluorinated compound by liquid-phase fluorination, comprising:

• a. continuously introducing, in a reactor a hydrogen-containing compound into a liquid perfluorocarbon, perhalogenated chlorofluorocarbon or chlorofluoroether medium while agitating the medium so that the hydrogen-containing compound is dissolved or dispersed within the liquid medium;
• b. introducing fluorine gas diluted with an inert gas into the medium to fluorinate the hydrogen-containing compound, the fluorine gas being diluted so that the liquid perfluorocarbon, perhalogenated chlorofluorocarbon or chlorofluoroether medium and fluorine gas in a vapor space, which is formed above the liquid medium, do not form a flammable mixture, the amount of fluorine gas being in excess of the stoichiometric amount needed to replace all of the hydrogen atoms of the hydrogen-containing compound with fluorine, whereby the diluted fluorine gas is introduced at a rate that is sufficient to remove the formed by-product hydrogen fluoride from the reactor while under conditions which produce the essentially perfluorinated compound;
• c. fluorinating until the hydrogen-containing compound is essentially perfluorinated, wherein the fluorination reaction is carried out in the absence of a hydrogen fluoride scavenger under conditions including a temperature below the boiling point of the liquid medium but sufficiently high to allow by-product hydrogen fluoride to be removed from the reactor, thereby producing the essentially perfluorinated compound;
• and
• d. removing the by-product hydrogen fluoride from the reactor while under conditions which produce the essentially perfluorinated compound.