(395u) Solubility of CO2 in Saline Water and Adsorption of CO2 On Clay Minerals From Subcritical to Supercritical Conditions

As carbon dioxide is well-known as a major contributor to greenhouse effect, capturing and sequestering CO₂ emission has emerged as one of the most important global issues. CO₂ storage in geological formations has been focused as a promising method to reduce anthropogenic CO₂ emission and especially, saline aquifers have the highest capacity for CO₂ storage. For this reason, the evaluation of the storage capacity and interaction was required between saline water and CO₂ and between constituent rocks and CO₂. Clay mineral is one of the major constituents of various rocks such as cap rock and coal mineral matter.

 In this study, CO₂ sorption experiments were conducted to confirm the sealing integrity, and the storage capacity of CO₂ in the saline water was measured. Several kinds of clay minerals were selected as adsorbents, and CO₂ adsorption experiments were carried out by a gravimetric method. According to the practical reservoir conditions, the experiments were performed from CO₂ subcritical and supercritical conditions. The structural and textural changes of clay minerals due to CO₂ sorption were observed by comparing the BET analysis between the raw material and post-experiment samples. In addition, the solubility experiments of CO₂ in the standard sea water were conducted and the change of pH with pressure was observed.