KINETICS STUDY OF THE PET WASTE THERMAL CRACKING The aim of this study is to calculate the kinetic parameters for thermal cracking of waste PET in presence of radical donors. The thermal decomposition of PET is carried out at different temperatures (693-773 K), high pressure and by using heavy paraffinic hydrocarbons as radical donors. A simple first order kinetic model was proposed for thermal cracking and kinetic parameters (A and E) were calculated. Radical donors assure a high degree of waste PET decomposition in valuable products as gas fraction, gasoline and middle distillate. The coke is very spongious and a small quantity of undecomposed PET is blocked inside of the cavities.