Post consumer poly(ethylene terephthalate) depolymerization by waste of battery acid hydrolysis

The reaction of post-consumer poly(ethylene terephthalate) (PET) with waste of battery acid (sulfuric acid solution as 7.8M determine by chemical titration) was investigated in terms of temperature, and time at particle size about 2mm. The reaction extent reached 80% in four days at 100 C and 90% in 5 hours at 132 C (boiling point of waste of battery acid solution). Terephthalic acid (TPA) obtained was purified and considered in the same level of quality of the commercial. It was concluded that the hydrolysis occurred preferentially at the chain ends and superficially, having as controller mechanism the acid diffusion into the polymer structure.