Keywords
pyrolysis
LDPE
HDPE
polypropylene
ZSM-5
liquid product
catalytic pyrolysis
process optimization.
How to Cite
Abstract
This study investigates the experimental optimization of plastic waste pyrolysis for maximizing liquid product yield using low-density polyethylene (LDPE), high- density polyethylene (HDPE), and polypropylene (PP) as feedstocks and ZSM-5 as a catalyst. Pyrolysis experiments were carried out over a temperature range of 150-700 °C, while the ZSM-5 loading was varied from 1 to 10% relative to the mass of the plastic feedstock. The influence of temperature, polymer type, and catalyst concentration on the formation of liquid, gaseous, and solid products was systematically evaluated. The results showed that increasing the temperature up to 500 °C significantly enhanced the formation of condensable hydrocarbons, whereas further temperature increases promoted secondary cracking and increased gas formation. Under non-catalytic conditions, the liquid yields of LDPE, HDPE, and PP were 79.8, 76.5, and 82.3%, respectively. The optimum ZSM-5 loading was determined to be 5%, providing maximum liquid yields of 87.4% for LDPE, 84.6% for HDPE, and 89.5% for PP. These findings demonstrate that controlled catalytic pyrolysis can effectively enhance the conversion of polyolefin waste into valuable liquid hydrocarbons and may provide a promising approach for plastic waste valorization and alternative hydrocarbon feedstock production.References
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Copyright (c) 2026 Yusuf Ergashev, Shamshidinxo'ja Saydaxmedov (Author)