Laboratory experiments and modelling of the geochemical interaction of a gabbro-anorthosite with seawater and supercritical CO2: A mineral carbonation study

The potential for mineral carbonation of carbon dioxide (CO2) in a plutonic mafic rock is addressed in this work through a set of laboratory experiments on a gabbro-anorthosite sample from the Torrão - Odivelas Massif (Portugal). The experiment was conducted in two stages under pressure (8 MPa) and temperature (313.15 K) conditions similar to those expected around a CO2 injection well. Stage-I simulated dissolution conditions, with a crushed rock sample (1–3 mm) exposed for 30 days to CO2 supersaturated seawater (0.576 M). Stage-II favoured carbonation conditions; cubic rock specimens (8 cm3) were brought in contact with the Stage-I seawater subsaturated in CO2 (0.095 M).