Fluorinated alkanoic acid purification process
AssigneeE. I. Du Pont de Nemours and Company
InventorJames Arnold Schultz
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Abstract
A process that can be used for isolating a fluorinated alkanoic acid from an aqueous solution also containing inorganic fluorides is provided. This process comprises (A) acidifying an aqueous solution comprising an ammonium salt of a fluorinated alkanoic acid to produce an acidified solution, (B) heating the acidified solution to produce an organic layer and an aqueous layer, (C) separating and recovering the organic layer from the aqueous layer, (D) optionally washing the organic layer with an acid solution, (E) optionally isolating the fluorinated alkanoic acid, and (F) further optionally converting the fluorinated alkanoic acid to its ammonium salt.
Claims12
A process comprising (A) acidifying an aqueous solution comprising an ammonium salt of a fluorinated alkanoic acid with an acid to produce an acidified solution, (B) heating said acidified solution to produce an organic layerwhich comprises said fluorinated alkanoic acid and an aqueous layer, (C) separating and recovering said organic layer from the aqueous layer, (D) washing said organic layer with an acid solution, (E) isolating said fluorinated alkanoic acid, and (F) optionally converting said fluorinated alkanoic acid to said ammonium salt wherein said acid used in step (A) contains less than about 50 volume % water;
- said acid solution used in step (D) contains less than about 10 volume % acid;
- and the pH of said acidified solution is about 2 or less.
Dependencies are inferred from the claim text.