| 摘要 |
<P>PROBLEM TO BE SOLVED: To enhance the operability of a carboxylic acid synthesizing process and to improve impurity removing effect. <P>SOLUTION: This method for removing impurities from the mother liquor containing a carboxylic acid, a metal catalyst and impurities comprises a step (a) to vaporize the mother liquor containing the carboxylic acid, the metal catalyst, impurities, water and a solvent and produce a vapor stream and a concentrated mother liquor stream in the first vaporizer zone, a step (b) to vaporize the concentrated mother liquor stream and form a solvent-enriched stream and an ultra-concentrated mother liquor stream in the second vaporizer zone, a step (c) to separate organic impurities from the ultra-concentrated mother liquor by a water-solvent solution and form a water-soluble stream and a second water-soluble stream in a solid-liquid separating zone, a step (d) to mix water and an extractant, as the case may be, with the water-soluble stream and the second water-soluble stream and form a water-soluble mixture in a mixing zone and a step (e) to add another extractant to the water-soluble mixture and form an extract stream and a raffinate stream in an extraction zone. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
