(2024) Journal of Hazardous Materials_Conversion of toxic pyrogenic products into syngas through catalytic pyrolysis of insulation material waste under the presence of CO₂

Kim J.-H.; Lee T.; Lee J.; Choi H.; Kwon E.E.

(Elsevier B.V.) Journal of Hazardous Materials ISSN: 3043894 Vol.476 Issue. Article No.134916 DOI: 10.1016/j.jhazmat.2024.134916

Plastic-based insulation materials have been widely employed owing to their exceptional durability, cost-effectiveness, low weight, and low thermal conductivity. Nevertheless, the disposal of the insulation material waste (IMW) within construction waste and its recycling and recovery are challenging. Meanwhile, landfilling or incineration methods can release toxic chemicals into the environment. Consequently, the accumulation of IMW in construction waste has become a pressing environmental concern. To address this issue, this paper proposes a pyrolysis platform as a disposal management method for IMW that employs CO₂ as a reactive medium. IMW composed of polystyrene in the form of extruded polystyrene underwent pyrolysis to yield pyrogenic products containing toxic chemicals. These toxic chemicals were subsequently transformed into syngas via homogeneous reactions with CO₂ under certain thermal conditions and Ni/Al₂O₃ catalyst. This resulted in a significant reduction in the total peak areas of toxic substances in the pyrogenic oil compared with that obtained using N₂ as a medium. Furthermore, the efficacy of CO₂ was demonstrated to increase with an increase in the atmospheric concentration. This study implied that catalytic pyrolysis under CO₂ conditions is a potential platform for converting toxic chemicals from IMW into syngas through homogeneous reactions with CO₂. © 2024 Elsevier B.V.

This study was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean Government (MSIT) (Grant No. NRF-2023R1A2C3003011). Jung-Hun Kim also acknowledges the financial support from the Hyundai Motor Chung Mong-Koo Foundation.