OBTAINING DICARBOXYLIC ACID BY METHOD OF SELF-ACTIVATED OXIDATIVE DESTRUCTION Russian patent published in 2016 - IPC C07C51/265 C07C63/26 C07C63/15 C07C63/24 C07C63/16 

FIELD: chemistry.

SUBSTANCE: invention relates to method for obtaining aromatic dicarboxylic acid, which includes (a) oxidation of aromatic compound in, at least, one oxidation installation with obtaining exhaust gas, formed in oxidation installation, and product, formed in oxidation installation, which represents aromatic dicarboxylic acid; (b) direct or indirect supply of, at least, part of said exhaust gas, formed in oxidation installation, into thermal oxidation destruction (TOD), where said TOD device represents installation of regenerative thermal oxidation; and (c) oxidation in said TOD device of, at least, said part of exhaust gas, formed in oxidation installation, where at set mode of said TOD device operation, at least, 60% of quantity of fuel, supplied into said TOD device, is supplied from said exhaust gas, formed in oxidation installation, or from products of reaction of said exhaust gas, formed in oxidation device. In particular invention relates to method for obtaining terephthalic acid, which includes (a) oxidation of paraxylene in, at least, one oxidation installation with obtaining exhaust gas, formed in oxidation installation, and product, formed in oxidation installation, which represents terephthalic acid; (b) direct or indirect supply of, at least, part of said exhaust gas, formed in oxidation installation, into device for thermal oxidation destruction (TOD), where said TOD device represents installation for regenerative thermal oxidation; and (c) oxidation in said TOD device of, at least, said part of exhaust gas, formed in oxidation installation, where, at least, part of said exhaust gas, formed in oxidation installation, which is oxidised in said TOD device, contains acetic acid in quantity, smaller than 0.005 kg/kg of said aromatic compound, supplied into said oxidation installation and contains carbon monoxide in quantity smaller than 0.45 kg/kg of said aromatic compound, supplied into said oxidation installation, and at set mode of said TOD device operation, at least, 70% of quantity of fuel, supplied into said device for thermal oxidative destruction, is supplied from said exhaust gas, formed in oxidation installation, and, at least, 90 mol.% of carbon-containing compound, present in, at least, said part of said exhaust gas, formed in oxidation installation, which is introduced into said TOD device, is oxidised in said TOD to carbon dioxide. With application of exhaust gas more energy is generated on shaft than it is required for bringing main compressor into action in order to obtain compressed air, even at preferable, relatively low temperatures of oxidation method.

EFFECT: invention provides better extraction of contained energy and work on shaft from exhaust gas after carrying out reactions of xylene oxidation and simultaneously minimised consumption for processing waste water.

31 cl, 1 dwg