Kazakhstan journal for oil & gas industryKazakhstan journal for oil & gas industry2707-42262957-806XKMG Engineering10898210.54859/kjogi108982Analysis of the influence of process parameters on the formation of liquid products during the pyrolysis of polystyrene wasteKizatovYesmagambetk1z4.workstation@gmail.comhttps://orcid.org/0009-0001-1078-3059DyussovaRizagul<p>Candidate of Technological Sciences, Acting Associate Professor</p>dyussova_rm@enu.kzhttps://orcid.org/0000-0003-3083-5255KopishevEldar Yertaevich<p>Cand. Sc. (Chemistry), Associate Professor</p>kopishev_eye@enu.kzhttps://orcid.org/0000-0002-7209-2341KaliyevOlzhas Yerlanuly<p>PhD student</p>kaliyev_oye_3@enu.kzhttps://orcid.org/0009-0008-4860-060XL.N. Gumilyov Eurasian National University820605202622052026Copyright © , Kizatov Y., Dyussova R.<p style="text-align: justify;">This paper examines the thermal recycling of polystyrene waste as an effective alternative to traditional mechanical recycling. Given the growing volume of plastic waste and the complexity of recycling foamed materials, the influence of temperature and process duration on the formation of liquid products with high added value was analyzed. Based on this analysis, it was found that the most efficient temperature range is 400–500°C. These conditions maximize the yield of a liquid fraction enriched with valuable aromatic compounds: styrene, benzene, toluene, and ethylbenzene. It was found that deviations from the optimal temperature lead to either incomplete polymer degradation or excessive gas formation. 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