Investigation of Heavy Polyethylene Catalytic Pyrolysis

Heavy polyethylene catalytic pyrolysis with ۱۵% HZSM-۵ catalyst was performed at ۵۰۰ ° C in a semi-continuous stirrer reactor under nitrogen gas. In the first experiment, about ۴۶.۷% of the liquid product, ۲۹.۲% of the gas product and ۴.۵% of coke was produced. In the second experiment, with the changes made on the reactor and condenser, the liquid product output increased by about ۸%. In a similar study, the effect of HZSM-۵ zeolite catalyst acidity on the catalytic degradation of heavy polyethylene was evaluated. To have HZSM-۵ with different acidities, sodium nitrate solution with different concentrations was used. Displacement of protons in the original sample by sodium cations (at room temperature for ۴ hours) reduces the acidity of the samples. By adding sodium to HZSM-۵ and ion transfer, the acidity of the catalyst decreased and the degradation temperature increased from ۳۹۰ °C to ۵۵۵ °C. The gases released from pyrolysis were also analyzed by gas chromatography and it was concluded that the selectivity of volatile products changes with catalytic acidity.

Keywords:

Heavy polyethylene , Catalytic Pyrolysis , HZSM , Gas Chromatography