Experimental Study on the CO2 Mineralisation Potential of German Igneous Rocks

Summary Following the recent amendment to the Carbon Dioxide Storage Act, the way has been paved for future underground storage of CO2 in Germany. However, the storage of gaseous CO2 in the subsurface still faces opposition in society as it is often perceived as unsafe. This study evaluates the potential of an alternative storage method involving the in-situ mineralisation of CO2. Injecting dissolved CO2 into geological formations, where it mineralises upon reacting with the surrounding rocks, may lead to greater public acceptance, since the CO2 is stored in solid carbonate minerals. Here we present the first in a series of batch reactor experiments testing the chemical ability of different mafic and ultramafic volcanic and plutonic rocks from Germany to sequester CO2 into carbonate minerals. The tested sample from the Vogelsberg volcanic complex was able to supply the necessary divalent metal cations to form carbonate minerals, which were successfully identified in the experimental products. Subsequent experiments will extend the study to a variety of different lithologies.