Process for the recovery of fluorinated carboxylic acids
AssigneeHoechst Aktiengesellschaft
InventorsReinhold Obermeier, Gunter Stefaniak
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Abstract
Fluorinated carboxylic acids can be recovered from materials which contain them by releasing, if necessary, the carboxylic acids with sufficiently strong acids, esterifying the released acids and distilling off the esters. The esters can be advantageously directly hydrolyzed with aqueous ammonia solution to give the corresponding ammonium salts.
Claims14
A process for preparing an ammonium salt of a fluorinated carboxylic acid emulsifier, which comprises hydrolyzing an ester of the fluorinated carboxylic acid in aqueous ammonia.
A process for purifying a crude solution of a fluorinated carboxylic acid emulsifier in which the emulsifier is present in the form of an ester, which comprises hydrolyzing the crude solution containing said ester with aqueous ammonia and recovering the emulsifier in the from of an ammonium salt.
Dependencies are inferred from the claim text.