Boosting CO₂ Sequestration Efficiency Through Additive-Driven Mineral Activation in Reactive Rocks

Increasing the rate of mineral carbonation of basaltic rocks is an encouraging route to long-term sequestration of CO₂; natural mineralization is limited by slow silicate dissolution and lack of cations. This paper focuses on the use of a CHEMICAL to increase basalt reactivity and speed up carbonate precipitation in simulated conditions of a reservoir. HH4, which is a non-porous basalt powder (HH4) was used with 5 and 10 % CHEMICAL A solution dissolved in synthetic seawater and exposed to supercritical CO₂ at 50 °C and 1200 psi over a period of six months. The quantity of released Ca²⁺, Mg²⁺, and Fe²⁺ was determined with the help of Inductively Coupled Plasma - Optical Emission Spectroscopy (ICP-OES), and solid-phase carbonate formation was verified with the help of Thermogravimetric Analysis (TGA). Findings indicated a distinct increase in cation dissolution with higher CHEMICAL A concentration with Fe²⁺ demonstrating the most mobilization of 5.5 times in comparison to the CO₂-brine baseline. The results of TGA indicated significant mass loss in 350 °C to 600 °C, which represents decomposition of Mg- and Fe-carbonates, and this corroborates the achievement of successful mineral carbonation. The results indicate that CHEMICAL A is effective in facilitating an eluent dissolution-precipitation process, which offers high capability to reduce the time scales in carbonation and enhance efficiency in CO₂ storage in basaltic systems.