Reactivity and CO2 Uptake in Thermally and Mechanochemically Activated Basaltic Fines and Olivine

Evidence indicates that injected CO 2 is mineralized over time by mafic and ultramafic minerals in basaltic formations. Accelerated carbonation of basaltic fines derived from quarry residues and similar materials is a promising approach to reducing CO 2 emissions in the concrete industry. This study explores CO 2 mineralization in basaltic fines and magnesium-rich olivine powders. Raw, mechanochemically (MCA), and thermally activated (TA) samples were carbonated under mild conditions. Aside from olivine, where TA did not enhance reactivity because its melting point exceeded the activation temperature, both MCA and TA increased the reactivity of the other samples by over 750%, turning them into reactive SCMs. All samples captured less than 1% CO 2 , except for the mechanochemically activated olivine, which achieved approximately 5.2% CO 2 uptake.