(2024) Cellulose_Reactivity of carbon dioxide during pyrolysis of paper-plastic composite

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

(Springer Science and Business Media B.V.) Cellulose ISSN: 9690239 Vol. Issue. Article No. DOI: 10.1007/s10570-024-05805-z

Composite materials have been widely used because of their superior properties compared to those of the original material. Separation of the constituent materials is not easy in the recycling process, and such an effort lowers economic viability. As such, this study employed a pyrolysis as a valorizing method for the composite material. Disposable paper cup waste (DPCW) was chosen as the model compound for paper-plastic composites. To offer green/sustainable features, CO₂ was employed as a raw and reactive material in the pyrolysis process. It was proved that DPCW primarily composed of cellulose (outer layer) and polyethylene (inner layer). In the single-stage and multistage pyrolysis of DPCW, the CO₂ reactivity in the homogeneous reaction of CO₂ and DPCW-derived volatiles was not rapid. To accelerate the reaction kinetics governing the reactivity of CO₂, the catalytic pyrolysis of DPCW over Ni/SiO₂ was performed. The formation of syngas increases significantly, suggesting that CO₂ reactivity was catalytically enhanced. The generation of syngas (enhanced by CO₂) was inversely related to the DPCW oil generation, indicating that more carbon was assigned from the oil to the gaseous pyrogenic products. The study results would offer a strategic means to valorize paper-plastic composites and CO₂ into energy through pyrolysis. © The Author(s), under exclusive licence to Springer Nature B.V. 2024.

This work was conducted with the support of “Cooperative Research Program for Agriculture Science & Technology Development (Project title: Valorization of livestock manure waste in the pyrolysis process, Project No. RS-2022-RD010000), and the Rural Development Administration, Republic of Korea. This study was supported by the Marine Ecology Enhancement Fund (MEEF) (No. MEEF2023006), SKLMP Seed Collaborative Research Fund (No. SKLMP/SCRF/0053), and a Dean Research Grant (No. IRS-7, and ICRS-7) at the Education University of Hong Kong. Jung-Hun Kim also acknowledges the financial support from the Hyundai Motor Chung Mong-Koo Foundation.