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AssigneeMinnesota Mining and Manufacturing Company
InventorsThomas C. Herzberg, Robert B. Fletcher, Randall F. Henderson
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A process for the purification of a perfluorochemical composition comprises continuously mixing the perfluorochemical composition, comprising a liquid mixture of inert perfluorochemicals (e.g., perfluoroalkanes, perfluoroethers, perfluoroaminoethers, or perfluoroalkyl tertiary amines) and isomeric fluorohydrochemicals, with a stabilization composition comprising water-miscible alkanol and an aqueous solution of base (such as potassium hydroxide) made by dissolving the base in an amount of water sufficient to dissolve or disperse the fluoride salt by-products of the subsequent reaction of the base with the fluorohydrochemicals to form fluoroolefins, the amount of the alkanol in the stabilization composition being in stoichiometric excess of the amount needed to completely convert the fluoroolefins to alkoxyvinyl ethers. The process can be utilized to purify the product mixtures resulting from fluorination methods such as direct fluorination or ECF.
A process for purifying a perfluorochemical composition which comprises continuously mixing said perfluorochemical composition, comprising a liquid mixture of inert perfluorochemicals and isomeric fluorohydrochemicals, with a stabilization composition comprising water-miscible alkanol and an aqueous solution of base made by dissolving said base in an amount of water sufficient to dissolve or disperse the fluoride salt by-products of the reaction of said base with said fluorohydrochemicals to form fluoroolefins, the amount of said alkanol in said stabilization composition being in stoichiometric excess of the amount needed to completely convert said fluoroolefins to alkoxyvinyl ethers.
A process for purifying a perfluorochemical composition which comprises (a) continuously mixing said perfluorochemical composition, comprising a mixture of (i) inert perfluorochemicals selected from the group consisting of C.sub.3 -C.sub.6 perfluoroalkanes, C.sub.3 -C.sub.6 perfluoroethers, C.sub.3 -C.sub.6 perfluoroaminoethers, and C.sub.3 -C.sub.6 perfluoroalkyl tertiary amines, or mixtures thereof, and (ii) isomeric fluorohydrochemicals, with a stabilization composition comprising methanol and an aqueous solution of potassium hydroxide made by dissolving said potassium hydroxide in an amount of water sufficient to dissolve the fluoride salt by-products of the reaction of said potassium hydroxide with said fluorohydrochemicals to form fluoroolefins, the amount of said potassium hydroxide in said aqueous solution being in stoichiometric excess of the amount of hydride in said fluorohydrochemicals, and the amount of said methanol in said stabilization composition being in stoichiometric excess of the amount needed to completely convert said fluoroolefins to alkoxyvinyl ethers;
Dependencies are inferred from the claim text.