a b s t r a c t
In this study, the methanolic pyrolysis (methanolysis) of poly(ethylene terephthalate) (PET) taken from
waste soft-drink bottles, under microwave irradiation, is proposed as a recycling method with substantial
energy saving. The reaction was carried out with methanol with and without the use of zinc acetate as catalyst
in a sealed microwave reactor in which the pressure and temperature were controlled and recorded.
Experiments under constant temperature or microwave power were carried out at several time intervals.
The main product dimethyl-terephthalate was analyzed and identified by FTIR and DSC measurements. It
was found that PET depolymerization, is favored by increasing temperature, time and microwave power.
High degrees of depolymerization were measured at temperatures near 180 ◦C and at microwave power
higher than 150 W. Most of the degradation was found to occur during the initial 5–10 min. Compared
to conventional pyrolysis methods, microwave irradiation during methanolic pyrolysis of PET certainly
results in shorter reaction times supporting thus the conclusion that this method is a very beneficial one
for the recycling of PET wastes.