Water and Carbon Dioxide Adsorption at Olivine Surfaces
Abstract
Plane-wave density functional theory (DFT) calculations were performed to simulate water and carbon dioxide adsorption at the (010) surface of five olivine minerals, namely, forsterite (Mg2SiO4), calcio-olivine (Ca2SiO4), tephroite (Mn2SiO4), fayalite (Fe2SiO4), and Co-olivine (Co2SiO4). Adsorption energies per water molecule obtained from energy minimizations varied from -78 kJ mol-1 for fayalite to -128 kJ mol-1 for calcio-olivine at sub-monolayer coverage and became less exothermic as coverage increased. In contrast, carbon dioxide adsorption energies at sub-monolayer coverage ranged from -20 kJ mol-1 for fayalite to -59 kJ mol-1 for calcio-olivine. Therefore, the DFT calculations show a strong driving force for carbon dioxide displacement by water at the surface of all olivine minerals in a competitive adsorption scenario. Additionally, adsorption energies for both water and carbon dioxide were found to be more exothermic for the alkaline-earth (AE) olivines than for the transition-metal (TM) olivines and to not correlate with the solvation enthalpies of the corresponding divalent cations. However, a correlation was obtained with the charge of the surface divalent cation indicating that the more ionic character of the AE cations in the olivine structure relative to the TM cations leads to greater interactions with adsorbed water and carbon dioxide molecules at themore »
- Authors:
- Publication Date:
- Research Org.:
- Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 1114889
- Report Number(s):
- PNNL-SA-96624
39937; KC0302060
- DOE Contract Number:
- AC05-76RL01830
- Resource Type:
- Journal Article
- Journal Name:
- Chemical Geology, 359:81-89
- Additional Journal Information:
- Journal Name: Chemical Geology, 359:81-89
- Country of Publication:
- United States
- Language:
- English
- Subject:
- density functional theory; ab initio molecular dynamics; water; carbon dioxide; carbon sequestration; olivines; orthosilicates; Environmental Molecular Sciences Laboratory
Citation Formats
Kerisit, Sebastien N., Bylaska, Eric J., and Felmy, Andrew R. Water and Carbon Dioxide Adsorption at Olivine Surfaces. United States: N. p., 2013.
Web. doi:10.1016/j.chemgeo.2013.10.004.
Kerisit, Sebastien N., Bylaska, Eric J., & Felmy, Andrew R. Water and Carbon Dioxide Adsorption at Olivine Surfaces. United States. https://doi.org/10.1016/j.chemgeo.2013.10.004
Kerisit, Sebastien N., Bylaska, Eric J., and Felmy, Andrew R. 2013.
"Water and Carbon Dioxide Adsorption at Olivine Surfaces". United States. https://doi.org/10.1016/j.chemgeo.2013.10.004.
@article{osti_1114889,
title = {Water and Carbon Dioxide Adsorption at Olivine Surfaces},
author = {Kerisit, Sebastien N. and Bylaska, Eric J. and Felmy, Andrew R.},
abstractNote = {Plane-wave density functional theory (DFT) calculations were performed to simulate water and carbon dioxide adsorption at the (010) surface of five olivine minerals, namely, forsterite (Mg2SiO4), calcio-olivine (Ca2SiO4), tephroite (Mn2SiO4), fayalite (Fe2SiO4), and Co-olivine (Co2SiO4). Adsorption energies per water molecule obtained from energy minimizations varied from -78 kJ mol-1 for fayalite to -128 kJ mol-1 for calcio-olivine at sub-monolayer coverage and became less exothermic as coverage increased. In contrast, carbon dioxide adsorption energies at sub-monolayer coverage ranged from -20 kJ mol-1 for fayalite to -59 kJ mol-1 for calcio-olivine. Therefore, the DFT calculations show a strong driving force for carbon dioxide displacement by water at the surface of all olivine minerals in a competitive adsorption scenario. Additionally, adsorption energies for both water and carbon dioxide were found to be more exothermic for the alkaline-earth (AE) olivines than for the transition-metal (TM) olivines and to not correlate with the solvation enthalpies of the corresponding divalent cations. However, a correlation was obtained with the charge of the surface divalent cation indicating that the more ionic character of the AE cations in the olivine structure relative to the TM cations leads to greater interactions with adsorbed water and carbon dioxide molecules at the surface and thus more exothermic adsorption energies for the AE olivines. For calcio-olivine, which exhibits the highest divalent cation charge of the five olivines, ab initio molecular dynamics simulations showed that this effect leads both water and carbon dioxide to react with the surface and form hydroxyl groups and a carbonate-like species, respectively.},
doi = {10.1016/j.chemgeo.2013.10.004},
url = {https://www.osti.gov/biblio/1114889},
journal = {Chemical Geology, 359:81-89},
number = ,
volume = ,
place = {United States},
year = {Thu Nov 14 00:00:00 EST 2013},
month = {Thu Nov 14 00:00:00 EST 2013}
}