Depolymerization of condensation polymers

The continuous process for obtaining pure terephthalic acid and glycol from polyethylene terephthalate waste comprising the steps:

• subjecting polyethylene terephthalate waste to neutral, aqueous hydrolysis in a hydrolysis zone at a temperature of between 200.degree. C. and 300.degree. C. and superatmospheric pressure of at least 15 atmospheres, said hydrolysis being conducted in the presence of decolorizing carbon in an amount of between 0.1 to 30 weight percent of said waste;
• removing supernatant liquid from said hydrolysis zone and filtering said liquid under conditions of high temperature and pressure to recover an aqueous solution of terephthalic acid and glycol;
• passing said aqueous solution of terephthalic acid and glycol to a crystallization zone and cooling said solution to a temperature of between -10.degree. C. and 200.degree. C. in said crystallization zone to thereby cause crystallization of terephthalic acid from said solution;
• separating by filtering or centrifuge said terephthalic acid crystals from the liquid in said crystallization zone and washing and drying said crystals to provide pure terephthalic acid;
• passing the liquid from said crystallization zone to a distillation zone and distilling said liquid to provide pure glycol.