Abstract
In the present study, various cap rocks have been experimentally reacted in water with supercritical CO
2
in geological storage conditions (
P
= 8 × 10
6
Pa and
T
= 80 °C) for 25 days. To characterize the potential CO
2
–water–rock interactions, an experimental setup has been built to provide additional information concerning the effects of structure, thermal and surface characteristics changes due to CO
2
injection with cap rocks. In addition, CO
2
adsorption capacities of different materials (i.e., clay evaporate and sandstone) are measured. These samples were characterized by XRD technique. The BET specific surface area was determined by nitrogen isotherms. In addition, thermal characteristics of untreated adsorbents were analyzed via TGA method and topography surfaces are identified by Scanning Electron Microscope (SEM). Taking into account pressure and temperature, the physical as well as chemical mechanisms of CO
2
retention were determined. Isotherm change profiles of samples for relative pressure range indicate clearly that CO
2
was adsorbed in different quantities. In accordance with the X-ray diffraction, a crystalline phase was formed due to the carbonic acid attack and precipitation of some carbonate.