Biogenic calcium waste as CaO adsorbents for CO2 capture: Progress and future outlook

Publication Type

Journal Article

Name of Author

• Gloria Adjei, World Bank Africa Centre of Excellence in Oilfield Chemicals Research, University of Port Harcourt, Port Harcourt, NigeriaFollow
• Ogbonna F. Joel, World Bank Africa Centre of Excellence in Oilfield Chemicals Research, University of Port Harcourt, Port Harcourt, Nigeria
• Sunday Sunday Ikiensikimama, University of Port Harcourt, Port Harcourt, Nigeria
• Victor J. Aimikhe, World Bank Africa Centre of Excellence in Oilfield Chemicals Research, University of Port Harcourt, Port Harcourt, Nigeria

Publication Date (Issue Year)

2025

Journal Name

Journal of Environmental Management

Abstract

This article reviews current developments and applications of biogenic calcium waste as a sustainable CaCO₃ source, aiming to eradicate waste while providing a competitive way for CO₂ capture in a calcium looping system. A broad overview of the carbonation performances of various bio-derived CaO sorbents is assessed based on their unique morphologies, crystal structures, and polymorphic forms. Eggshells and Mactra veneriformis shells achieved initial carbonation conversions of up to 86 %, significantly outperforming limestone at 21 %, however suffer sharp cyclic adsorption decay due to sintering. To address the issue of severe sintering during calcination and to improve the cyclic performance of bio-based sorbents, this work discusses modification techniques for enhanced capture performance and sintering resistance. Bauxite-tailings containing 37 wt % of Al₂O₃ and 25.48 wt% of SiO₂, achieved 55 % conversion after 40 cycles, nearly doubling that of unmodified eggshells. A Life Cycle Analysis highlights the reduced environmental footprint the calcium looping process, and techno-economic data confirm lower costs per ton of CO₂ captured compared to conventional systems. A review of CO₂ capture kinetics is also included. The article concludes with recommendations for advancing waste shell utilization in industrial-scale carbon capture.

Keywords

CO2, captureCaO, sorbent, Calcium looping, Waste shells, Eggshells, LCAShell

Rsif Scholar Name

Gloria Adjei

Rsif Scholar Nationality

Ghana

Cohort

Cohort 4

Thematic Area

Energy including Renewables

Africa Host University (AHU)

University of Port Harcourt (UNIPORT), Nigeria

Funding Statement

The financial support from Partnership for Skills in Applied Sciences Engineering and Technology -Regional Scholarship Innovation Fund (PASET-RSIF) 

Recommended Citation

Adjei, G., Joel, O. F., Ikiensikimama, S. S., & Aimikhe, V. J. (2025). Biogenic calcium waste as CaO adsorbents for CO2 capture: Progress and future outlook. Journal of Environmental Management https://doi.org/doi.org/10.1016/j.jenvman.2025.127576