Experimental Investigation of Mafic Rocks for Carbon Mineralization Prospect

Carbon capture and storage by mineralization (CCSM) in mafic rock is a viable technology to store captured gaseous carbon dioxide (CO₂) into carbonate minerals by chemical reaction with rocks. Here, we investigate the interaction of CO₂ with four outcrop mafic rock samples of the Saudi Arabian region for their CCSM potential. Samples interacted with CO₂ at 8.27 MPa and 343 K in a batch reactor system for 2 months, and petrophysical and geomechanical properties were analyzed before and after CO₂ treatment. The results indicate that the initial state of samples is compromised after exposure to CO₂. X-ray diffaction and scanning electron microscopy analyses confirm the reactivity of CO₂ with samples. Petrophysical and mechanical parameters also changed after interaction with CO₂; i.e., porosity decreased, while Young’s modulus and hardness increased. The results of this study thus shed light on rapid carbon mineralization in the mafic rocks of Saudi Arabia, which can have direct implications for CO₂ geo-sequestration in the region.