Cracking Behavior of Upgraded Waste Plastic Pyrolysis oil to lighter olefins (C 2 -C 3 ): A study on Performance, Product Distribution and Outlook for a Circular Hydrocarbon Economy

Abstract

This study investigates the catalytic cracking of upgraded waste plastic pyrolysis oils (PPO), which includes chemically treated (CPO) and distilled (DPO) pyrolysis oils. Cracking was done using commercial spent FCC catalyst in a fixed-bed reactor, operating within the temperature range of 500 °C to 600 °C to produce light olefins (C 2 -C 3 ). The influence of DPO, CPO, and PPO on product distribution and catalyst performance is examined. The findings reveal that DPO yields the highest cracking toward light olefins, with a yield of 61.1 mol% at 550 °C with a WHSV of 2 h -1 as compared to CPO and PPO. In contrast, CPO and DPO resulted in higher conversion of methane (26.4 mol% and 25.7 mol%, respectively), followed by the lowest in DPO (17 mol%). Time-on-stream analysis (TOS) revealed that DPO's lighter olefin conversion has declined, particularly in ethylene yield from 31.09 mol% to 12.13 mol% over time as compared to CPO, maintained at 23.5 mol%. This study contributes to the prospect of upgraded PPO as an alternative to naphtha feed with optimized reaction conditions, such as temperature and WHSV, for high yields of olefins in a petrochemical hydrocracker unit.