The competition between H₂O and CO₂ adhesion at reservoir conditions: A DFT study of simple mineral models and the entropy, ZPE, dispersion and T,P variations

TY - JOUR

T1 - The competition between H2O and CO2 adhesion at reservoir conditions

T2 - A DFT study of simple mineral models and the entropy, ZPE, dispersion and T,P variations

AU - Sølling, Theis Ivan

AU - Budi, Akin

AU - Mogensen, K.

PY - 2015/12/1

Y1 - 2015/12/1

N2 - Density functional theory was applied (B3LYP) to answer whether conditions exist where CO2 adhesion to three different lithologies becomes stronger than H2O adhesion. The answer is that it does not seem to be the case. This is taken to indicate that the reservoirs that we have represented by simple models are prone to CO2 storage. Moreover, we have obtained an overview of the effect of including entropy contributions and zero point vibrational energies in the calculation of the adhesion energies. The consequence of applying simple dispersion and solvent models are also addressed. The study is based around very simplified model systems of calcite, quartz and clays in order address the basic effects. Rather than attempting to obtain quantitative agreement we are observing the qualitative trends. When entropy, ZPE and a continuum model is included the result is smaller binding energies. However, the inclusion of dispersion effects leads to the prediction of a much stronger binding. There is a tendency for the clay model to bind water the strongest, this indicate a potential impact of having clay present in media for capillary trapping of carbon dioxide.

AB - Density functional theory was applied (B3LYP) to answer whether conditions exist where CO2 adhesion to three different lithologies becomes stronger than H2O adhesion. The answer is that it does not seem to be the case. This is taken to indicate that the reservoirs that we have represented by simple models are prone to CO2 storage. Moreover, we have obtained an overview of the effect of including entropy contributions and zero point vibrational energies in the calculation of the adhesion energies. The consequence of applying simple dispersion and solvent models are also addressed. The study is based around very simplified model systems of calcite, quartz and clays in order address the basic effects. Rather than attempting to obtain quantitative agreement we are observing the qualitative trends. When entropy, ZPE and a continuum model is included the result is smaller binding energies. However, the inclusion of dispersion effects leads to the prediction of a much stronger binding. There is a tendency for the clay model to bind water the strongest, this indicate a potential impact of having clay present in media for capillary trapping of carbon dioxide.

KW - Wettability

KW - Co2 absorption

KW - Storage

KW - Clays

KW - Wettability

KW - CO2 absorption

KW - Storage

KW - Clays

U2 - 10.1016/j.comptc.2015.09.015

DO - 10.1016/j.comptc.2015.09.015

M3 - Journal article

SN - 2210-271X

VL - 1073

SP - 55

EP - 60

JO - Computational and Theoretical Chemistry

JF - Computational and Theoretical Chemistry

ER -