摘要 |
Improvement in separating lower carboxylic acids from aqueous streams via liquid-liquid extraction with pressurized liquefied propylene and/or propane, wherein carboxylic acid is transferred from the aqueous phase into the liquid solvent phase (extract). The extracted carboxylic acids are recovered as a liquid concentrate by evaporating off the propylene and/or propane solvent from the extract at mild temperatures. |