METHOD OF PRODUCING TEREPHTHALIC ACID FROM POLYETHYLENE TEREPHTHALATE WASTES Russian patent published in 2020 - IPC C07C63/26 C07C51/09 C08F8/12 C08J11/10 

FIELD: technological processes.

SUBSTANCE: invention relates to a method of producing terephthalic acid (TPA) from polyethylene terephthalate (PETP) wastes (for example, used bottles of different beverage colors) and can be used both for producing TPA and for recycling PETP wastes. Method of producing TPA involves grinding PETP wastes, holding them in a nitriding atmosphere obtained by evaporating 12 mol/l of nitric acid, at temperature 130–190 °C for 5–24 hours, treatment with sodium hydroxide solution with formation of disodium salt of TPA and deposition of TPA with monobasic mineral acid with subsequent filtration, washing and drying.

EFFECT: advantages of the invention are obtaining terephthalic acid from polyethylene terephthalate wastes without use of toxic substances, as well as possibility of its use for recycling of PETP wastes without their preliminary division on color gamma.

1 cl, 6 dwg