METHOD FOR WASTE PET ALKALINE HYDROLYSIS WITH TEREPHTHALIC ACID PRODUCTION Russian patent published in 2017 - IPC C08J11/16 C08J11/22 C07C63/26 C07C51/347 

FIELD: chemistry.

SUBSTANCE: invention relates to a method for polyethylene terephthalate (PET) waste alkaline hydrolysis with terephthalic acid (TPA) release, which can then be used to obtain ester PVC plasticizers. The claimed method for PET waste alkaline hydrolysis to produce terephthalic acid comprises PET hydrolysis with sodium hydroxide in a flotation reagent oxalyl T-92 medium at heating, followed by water addition to the reaction mass until complete dissolution of the resulting TPA disodium salt, aqueous layer separation from the flotation reagent oxalyl T-92, TPA precipitation from to aqueous solution by concentrated hydrochloric acid, followed by TPA filtration, washing and drying, wherein the PET waste are used in the form of 3-5 mm flakes, and reagents are taken in a weight ratio of PET:NaOH:flotation reafent oxal T-92=1:(0.5-0.8):(4-6), and the hydrolysis process is carried out at a temperature of 130-150°C and atmospheric pressure for 3-5 h.

EFFECT: cost reduction and obtaining of high quality TPA.

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