(2024) Energy_Thermo-chemical disposal of plastic waste from end-of-life vehicles (ELVs) using CO₂

Kim J.-H.; Jung S.; Lee T.; Tsang Y.F.; Kwon E.E.

(Elsevier Ltd) Energy ISSN: 3605442 Vol.290 Issue. Article No.130136 DOI: 10.1016/j.energy.2023.130136

The source reduction of plastic waste could be an effective means to attenuate hazardous environmental problems triggered by microplastics. Energy recovery from plastic waste through thermochemical processes is a desirable valorization route. To realize the grand challenges, plastic waste derived from end-of-life vehicles (ELVs) was pyrolyzed. To propose a greener feature, CO₂ was introduced as a mediator to maximize carbon allocation to the gaseous pyrogenic product (syngas) by CO₂ reduction to CO and concurrent oxidation of volatile matter (VM) that was evolved from the thermolysis of plastic waste. As such, fundamental and systematic works were conducted to delineate the CO₂ effects on conversion of VMs. This study experimentally proved that CO₂ promotes thermal cracking in line with C–C bond scissions. However, the reaction rate for the conversion of CO₂ and VM into CO via homogeneous reaction was not fast. Therefore, a Ni-based catalyst was employed to accelerate the reaction rate. However, there was coke deposition on the catalyst surface. To prevent coke formation, we chose a method to enhance CO₂ reduction to CO and the oxidation of VM. Thus, three bimetallic catalysts were used for catalytic pyrolysis. Among the three bimetallic catalysts, Rh0.1Ni1/SiO₂ was the most effective. © 2023 Elsevier Ltd

This work was supported by the National Research Foundation of Korea ( NRF ) grants provided by the Korean government ( MSIT ) ( NRF-2023R1A2C3003011 ), the Environment and Conservation Fund of the Hong Kong Special Administrative Region Government (No. 2020–76 ), and the Internal Research Grant (No. IRS-7/ROP-10/RG30/2021-2022R ) of the Education University of Hong Kong . This research was supported by Basic Science Research Program through the National Research Foundation of Korea ( NRF ) funded by the Ministry of Education ( NRF-2021R1I1A1A01052241 ). Jung-Hun Kim also acknowledges the financial support of the Hyundai Motor Chung Mong-Koo Foundation .