| Abstrakt: |
Hydrolytic depolymerization of PET (polyethylene terephthalate) waste in excess of water was studied using a 0.5-L stirred high-pressure autoclave at temperatures of 100, 150, 200, and 250°C and at 200, 300, 400, 500, 700, and 800 psi (pounds per square inch) pressure. Velocity constants of hydrolysis were calculated from the experimental data obtained. Maximum depolymerization (91.38%) of PET into monomer was obtained at 250°C and 800 psi. pressure. However, the maximum rate of reaction was recorded at 200°C and 500 psi temperature and pressure, respectively. The energy of activation and frequency factor were calculated, as 64.13 KJ/g mol and 7.336 × 104 min−1, respectively, for higher pressure and temperature conditions. It was also reported that the hydrolytic depolymerization is first order with the velocity constant 1.773 × 10−2 min−1 at 250°C. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 33053309, 2003 |
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