Some kinetic parameters have been determined in this work for thermal and catalytic
cracking of the mixed of polyethylene and polypropylene using batch method. The
cracking reaction was carried out at different temperature 470,490 and 510oC under
atmospheric pressure. The mass of products (liquid and gas fractions) were determined and
used to plot the curves of the thermal and catalytic decomposition. We used two types of
catalysts: Syrian natural Zeolite and the same after loading with sulfate ions using
impregnation method. The thermal cracking has a long time and has firs-pseud order
reaction. While in the case of catalytic process we note that the reaction finished in the
short time and the process is the Zero-pseud order reaction. The rate of the cracking
increased very much, the rate constant was k1=0.0032.min-1 in the thermal cracking at
4700C and ko=0.111.min-1 in the case of catalytic cracking in presence of Z catalyst and
ko= 0.206 min-1 in presence of 15-SO4
2-/Z as catalytic at the same temperature. In the other
hand activation energy was 208.7 kj/mol in the thermal process and decreased to 116.6
kj/mol at Z catalytic presence and to 87.3 kj/mol at 15-SO4
2-/Z catalytic presence.