Abstract The co-pyrolysis of polycarbonate (PC) and polyethylene (PE)/polypropylene (PP) in the presence of HZSM-5 catalyst was studied in a two-stage tube reactor with the objective of promoting simultaneous deoxygenation and aromatic hydrocarbon formation, at atmospheric pressure and without external hydrogen addition. As the blending ratio of PE/PP increased, the yield of oil phase product, coke, and solid decreased, and the yield of gas phase increased significantly. At the blending ratio of 75% PP, the concentration of oxygenates in the oil was reduced to 2.9% and that of aromatic hydrocarbons increased to 97.1%. Increasing the reaction temperature from 500 °C to 700 °C increased the yield of aromatic hydrocarbons further to 98.1%. Catalyst regeneration decreased the acidity of the HZSM-5 catalyst, resulting in a slight decrease in the deoxygenation and aromatization effects. The results showed that PP is an effective hydrogen donor in the catalytic deoxygenation and aromatization process; the hydrogen provided enhanced the adsorption of phenols produced by the pyrolysis of PC on HZSM-5 and their direct deoxygenation to form new aromatic hydrocarbons.

中文翻译：

---

聚碳酸酯和聚乙烯/聚丙烯混合物的催化共热解：促进油脱氧和芳烃形成

摘要 在两级管式反应器中研究了在 HZSM-5 催化剂存在下聚碳酸酯 (PC) 和聚乙烯 (PE)/聚丙烯 (PP) 的共热解，目的是促进同时脱氧和芳烃形成，在常压且无需外部加氢。随着PE/PP掺混比的增加，油相产物、焦炭和固体的产率下降，气相产率显着增加。在 75% PP 的混合比例下，油中含氧化合物的浓度降低到 2.9%，芳香烃的浓度增加到 97.1%。将反应温度从 500 °C 提高到 700 °C，芳烃的产率进一步提高到 98.1%。催化剂再生降低了 HZSM-5 催化剂的酸度，导致脱氧和芳构化作用略有下降。结果表明，PP是催化脱氧和芳构化过程中有效的氢供体；所提供的氢气增强了 PC 在 HZSM-5 上热解产生的苯酚的吸附及其直接脱氧形成新的芳烃。