METHOD OF PRODUCING TEREPHTHALIC ACID DIAMIDE Russian patent published in 2013 - IPC C07C233/65 C07C231/02 

FIELD: chemistry.

SUBSTANCE: disclosed is a method of producing terephthalic acid diamide (TPADA) which is suitable for use as raw material for producing p-phenylene diamine which can be used in producing polymers. The method involves reaction of terephthalic acid with ammonia gas, the terephthalic acid being obtained from terephthalic acid production wastes which are terephthalic acid with toluic acid impurities and impurities with an unknown composition; removing impurities via extraction thereof with alcohol-containing wastes from production of food-grade alcohol with concentration of ethyl alcohol of 0.1-92% with weight ratio of terephthalic acid production wastes to ethanol of not less than 1.0:0.5 at temperature ranging from 50°C to the boiling point of the mixture of terephthalic acid production wastes and food-grade alcohol production wastes for 15-30 minutes, to obtain pure terephthalic acid and further reaction thereof with ammonia gas in molar ratio of terephthalic acid to ammonia of 1.0:2.1-10.0 at temperature of 40-70°C and pressure of 10.5-20.0 kg/cm² until formation of a diammonium salt of terephthalic acid, and then at temperature of 220-240°C in an ammonia current until the release of water ceases.

EFFECT: wider raw material base for producing terephthalic acid diamide and enabling recycling of industrial wastes from production of terephthalic acid and food-grade alcohol.

1 cl, 5 ex