Hydrolysis of poly (ethylene terephthalate) , PET, was carried out in water at temperatures of 250 and 270^oC using a pressure reactor with stirring. The principal ingredients of a reaction mixture were identified as terephthalic acid, mono (2-hydroxyethy1) terephthalate, ethylene glycol and di (ethylene glyco1). Precipitated terephthalic acid was recovered from the reaction mixture by centrifugal separation and the yield reached ca.93% for the reaction of 2 and 3g of PET/ca.10g of water. Other ingredients were held in aqueous solution, and mono (2-hydroxyethy1) terephthalate could be separated out by deposition
