(2025) Energy_CO₂-mediated pyrolysis for syngas generation from wood-plastic composite waste

Kwon D.; Kim J.Y.; Song H.; Lee J.; Tsang Y.F.; Kwon E.E.

(3605442) Energy ISSN:  Vol.319 Issue. Article No.134917 DOI: 10.1016/j.energy.2025.134917

Wood-plastic composites (WPCs) are extensively utilized in construction, furniture, and outdoor applications due to their superior physicochemical properties. However, their low biodegradability presents a critical challenge for waste management. This study explores upcycling WPC waste into syngas via CO₂-mediated pyrolysis. CO₂ serves as reaction medium, enhancing thermal decomposition and partial oxidation of volatile matters (VMs) generated from pyrolysis of WPCs to form carbon monoxide (CO) through homogeneous reactions. To further optimize the role of CO₂, a multi-stage pyrolysis operating isothermally at 700 °C was employed. In this configuration, the reactivity of CO₂ was more pronounced at lower temperatures than that during single-stage pyrolysis, indicating that the additional thermal energy accelerated CO₂-induced reactions. The introduction of a nickel-based catalyst accelerated the CO₂-induced homogeneous reactions by facilitating the adsorption and reaction of CO₂ with VMs during pyrolysis. Thus, utilizing CO₂ as a reaction medium in the catalytic pyrolysis process represents a strategic pathway for the upcycling of WPC waste. © 2025 Elsevier Ltd

This study was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean Government (MSIT) (No. RS- 2023-00219667), the SKLMP Seed Collaborative Research Fund (No. SKLMP/SCRF/0053), and the Dean’s Research Fund (No. RG12/2024- 2025R/ICRS-7/ICRS-8) at The Education University of Hong Kong. Dohee Kwon acknowledges the financial support from the Hyundai Motor Chung Mong-Koo Foundation. Elsevier Ltd