Kinetic Analysis of CO₂ Gasification for Maize Cob-Polypropylene Blended Biochar

CO₂ gasification of biomass represents a promising pathway toward carbon neutrality. While current research predominantly focuses on biomass carbonization with plastics or CO₂ gasification of pure biochar, the critical relationship between physicochemical structures and gasification reactivity remains underexplored. The present work explores the CO₂ gasification behavior of biochar derived from maize cob-polypropylene (PP) blends. The experimental results demonstrate that PP blending significantly enhances the gasification reactivity of maize cob-derived biochar. Structural characterization revealed that increasing the PP mass ratio led to an enhancement in specific surface area, which was the primary factor of biochar reactivity improvement. The thermogravimetric data were analyzed using both the random pore model (RPM) and unreacted core model (URCM). Comparative analysis confirmed that the RPM provided the best fit for the gasification process, with activation energy decreasing from 219.3 kJ/mol to 162.2 kJ/mol as the PP content increased from 0% to 60%.