Effect of dissolved H2SO4 on the interaction between CO2-rich brine solutions and limestone, sandstone and marl

The effect of pure and impure carbon dioxide (CO2) on geological storage is uncertain. Oxidation of impurities such as sulfur dioxide (SO2) and hydrogen sulfide (H2S), which may be catalyzed by co-injected oxygen or nitrogen oxides, leads to the formation of sulfuric acid (H2SO4) and a decrease in pH of the formation water. We investigated the effect of 0.005 mol L− 1 H2SO4 (corresponding to a worst case of 0.4% SO2 in the flue gas, anticipating...