| abstract |
PCT No. PCT/GB95/00535 Sec. 371 Date Nov. 12, 1996 Sec. 102(e) Date Nov. 12, 1996 PCT Filed Mar. 13, 1995 PCT Pub. No. WO95/25081 PCT Pub. Date Sep. 21, 1995The invention provides a process for the recovery of a water-soluble carboxylic or mineral acid having a pKa higher than 2 from an aqueous feed solution containing the acid or a salt thereof, comprising extracting the acid with a water-immiscible extractant composition, the composition comprising: (a) at least one secondary or tertiary aklyl amine, in which the aggregate number of carbon atoms is at least 20, as a primary extractant; and (b) a sterically hindered, polar, organic compound having at least 5 carbon atoms, a basicity weaker than that of the primary extractant, and temperature-sensitive, extraction-modifying properties; separating the acid containing the extractant and subjecting it to a stripping operation at a temperature of at least 20 DEG C. higher than the temperature at which the extraction is carried out, wherein the sterically hindered, polar, organic compound both modifies the extracting power of the primary extractant composition and facilitates the temperature-sensitive stripping operation. The invention also provides an extractant composition for use in such a process. |