| 摘要 |
The invention provides a process for the recovery of a water soluble carboxy lic or mineral acid having a pKa higher than 2 from an aqueous feed solution containing the acid or a salt thereof, comprising extr acting the acid with a water-immiscible extractant compo sition, the composition comprising: (a) at least one secondary or tertiary alkyl ami ne, in which the aggregate number of carbon atoms is at least 20, as a primary extractant; and (b) a sterically hindered, polar, organic c ompound having at least 5 carbon atoms, a basicity weake r than that of the primary extractant, and temperature-sensitive, extraction-modify ing properties; separating the acid containing the extra ctant and subjecting it to a stripping operation at a temperature of at least 20 .degr ee.C higher than the temperature at which the extraction is carried out, wherein the sterically hindered, polar, organic compound both modifies the e xtracting power of the primary extractant composition an d facilitates the temperature-sensitive stripping operation. The invention als o provides an extractant composition for use in such a p rocess.
|
