Clark et al. (2025): Does the release of toxic metals due to subsurface CO₂ storage in basalts pose an environmental hazard?
Deirdre E. Clark, Iwona M. Galeczka, Sigurður R. Gíslason, Sandra Ó. Snæbjörnsdóttir, Ingvi Gunnarsson, Eric H. Oelkers, IN: International Journal of Greenhouse Gas Control, https://doi.org/10.1016/j.ijggc.2025.104526
Carbon dioxide storage through the carbonation of subsurface basaltic rocks is currently being explored to limit carbon emissions to the atmosphere. Basaltic rocks, however, contain trace and toxic metals that could potentially be mobilized by the carbonation process. This study reports the degree to which selected trace and toxic metals were mobilized during CarbFix1 and CarbFix2 projects. CarbFix1 injected 175 tons of CO₂-charged water followed by 73 tons of CO₂/H₂S-charged water into basalts at 35 °C, whereas CarbFix2 continuously injected CO₂/H₂S-charged water into basalts at >250 °C.