Patent ID: 8173834
Filing Date: 2012-05-08
Classification: B01D,B01J,C07C,Y02P

Abstract:
1. A process for manufacture of aromatic carboxylic acid comprising contacting a feed material comprising at least one substituted aromatic hydrocarbon in which the substituents are oxidizable to carboxylic acid groups with gaseous oxygen in a liquid phase oxidation reaction mixture comprising monocarboxylic acid solvent and water and in the presence of a catalyst composition comprising at least one heavy metal component in a reaction zone at temperature and pressure effective to maintain a liquid phase oxidation reaction mixture and form an aromatic carboxylic acid and impurities comprising oxidation by-products of the substituted aromatic hydrocarbon dissolved or suspended in the liquid phase oxidation reaction mixture and a high pressure vapor phase comprising solvent monocarboxylic acid, water and minor amounts of the substituted aromatic hydrocarbon and by-products; transferring a high pressure vapor phase removed from the reaction zone to a separation zone supplied with liquid reflux comprising water and capable of separating monocarboxylic acid solvent and water in the high pressure vapor phase to form a solvent monocarboxylic acid-rich, water lean liquid and a high pressure gas comprising water vapor; transferring a high pressure gas comprising water vapor removed from the separation zone to a condensing zone without treatment to remove organic impurities and condensing the high pressure gas to form a condensate liquid comprising water and substantially free of organic impurities and a condensing zone exhaust gas under pressure comprising incondensable components of the high pressure gas transferred to the condensing zone from the separation zone without treatment to remove organic impurities; recovering from the condensing zone condensate liquid that comprises water substantially free of organic impurities; and directing condensate liquid comprising water substantially free of organic impurities recovered from the condensing zone without additional treatment to a process for purification of aromatic carboxylic acid which uses the condensate liquid comprising water substantially free of organic impurities in at least one step of the purification process, wherein the purification process comprising at least one step which comprises: (a) forming a purification reaction solution comprising aromatic carboxylic acid and impurities dissolved or slurried in a liquid comprising water; (b) contacting a purification reaction solution comprising aromatic carboxylic acid and impurities in a liquid comprising water at elevated temperature and pressure with hydrogen in the presence of a hydrogenation catalyst to form a purification liquid reaction mixture; (c) recovering solid purified product comprising aromatic carboxylic acid with reduced levels of impurities from a purification liquid reaction mixture comprising the aromatic carboxylic acid and impurities in a liquid comprising water; and (d) washing with at least one liquid comprising water a solid purified aromatic carboxylic acid product recovered from a purification liquid reaction mixture comprising the aromatic carboxylic acid, impurities and a liquid comprising water.