CARBON DIOXIDE EMISSIONS ESTIMATION FROM CARBON DIOXIDE ADSORBENT PRODUCTION USING UNBURNED CARBON RESIDUES FROM BIOMASS POWER PLANT

Abstract

This study evaluates the carbon dioxide (CO₂) emissions and net carbon reduction potential of CO₂ adsorbents produced from unburned carbon residues generated by a biomass power plant. Two activation methods—steam activation and chemical activation using potassium hydroxide—were investigated. The physical properties, pore structure, and CO₂ adsorption performance at 298 K and 1 bar were analyzed in conjunction with a gate-to-gate carbon emission assessment of the production process. The results demonstrate that chemical activation yields adsorbents with the highest specific surface area and CO₂ adsorption capacity, reaching 0.089 kgCO₂/kg, whereas steam-activated materials exhibit comparatively lower performance. Although chemical activation involves additional carbon emissions associated with chemical consumption, the resulting adsorbent requires a significantly lower number of carbon payback cycles than the steam-activated counterpart. These findings indicate that the evaluation of CO₂ adsorbents should simultaneously consider adsorption performance and embodied carbon emissions from the production process, enabling the selection of technologies that genuinely contribute to greenhouse gas mitigation from a system-level perspective.