EGU25-14981, updated on 15 Mar 2025
https://doi.org/10.5194/egusphere-egu25-14981
EGU General Assembly 2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
Geochemical Modelling for Carbon Mineralisation
Km Divya Gupta, Shreya Katre, and Archana M Nair
Km Divya Gupta et al.
  • Indian Institue of Technology, Guwahati, Civil Engineering, Guwahati, India (divyagupta072001@gmail.com)

Abstract. Carbon mineralization is the process of converting CO₂ into stable carbonate minerals through chemical reactions with reactive minerals such as silicates or oxides. This study investigates the carbon mineralization potential of wollastonite for carbon dioxide (CO2) sequestration through geochemical modelling. For this purpose, geochemical simulation was conducted using kinetic batch modelling under varying conditions, including temperatures ranging from 35 to 90 °C, pressures between 100 to 200 atm, and salinities from 0 to 2 mol/L NaCl for 20 days using PHREEQC (Version 3.7.3, USGS). The kinetic batch modelling results were explained that wollastonite dissolution increased with higher pressures and salinities, within the tested ranges of 100 – 200 atm and 0 – 2 mol/L NaCl, respectively. However, as the temperature increased from 35 to 90 °C, calcium concentration decreased by 55 % for 0 M salinity (Pure water). Besides, it is clear from the finding that carbonation efficiency shows a minimal variation (±1%) with changes in pressure at a constant temperature of 65°C in pure water, whereas it improved significantly by 52 % with changes in temperature from 0 to 90 °C at constant pressure on 150 atm in pure water. These results provide important understanding into the CO2 mineralization processes of calcium silicates such as wollastonite under geological carbon sequestration (GCS) conditions. They contribute to a deeper understanding of how injected CO2 behaves and interacts geochemically within subsurface environments, emphasizing the potential of these silicate minerals for efficient carbon capture and storage.

Keywords: Geological carbon sequestration; Kinetic batch modelling.

How to cite: Gupta, K. D., Katre, S., and Nair, A. M.: Geochemical Modelling for Carbon Mineralisation, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-14981, https://doi.org/10.5194/egusphere-egu25-14981, 2025.