Molecular Dynamics Simulation Study of Carbon Dioxide, Methane, and Their Mixture in the Presence of Brine

Handle URI:
http://hdl.handle.net/10754/625849
Title:
Molecular Dynamics Simulation Study of Carbon Dioxide, Methane, and Their Mixture in the Presence of Brine
Authors:
Yang, Yafan; Nair, Arun Kumar Narayanan; Sun, Shuyu ( 0000-0002-3078-864X )
Abstract:
We perform molecular dynamics simulation study of CO2, methane, and their mixture in the presence of brine over a broad range of temperature (311–473 K), pressure (up to about 100 MPa), and NaCl concentration (up to about 14 wt %). The general decrease in the interfacial tension (IFT) values of the CH4–brine system with pressure and temperature is similar to that obtained for the corresponding CH4–water system. The IFT of methane and brine is a linearly increasing function of salt concentration, and the resulting slopes are dependent on the pressure. A similar behavior as methane is observed for such systems containing CO2 and CO2–CH4 mixture. The IFT of CO2 and brine increases linearly with increasing salt content; however, the resulting slopes are independent of pressure. The simulations show that the presence of CO2 decreases the IFT values of the CH4–water and CH4–brine systems, but the degree of reduction depends on the amount of CO2 in each sample, which is consistent with experimental evidence. These IFT values show a linear correlation with the amount of CO2, and the resulting slopes are dependent on the temperature and pressure. Furthermore, our results for the mole fractions of the different species in the CO2–CH4–water system at 323 K and 9 MPa are in agreement with those of experiments. The mole fractions of methane and CO2 in the water-rich phase decrease with increasing salt concentration, whereas that of H2O in the methane- or CO2-rich phases remains almost unaffected in all of the studied cases. Our results could be useful because of the importance of carbon dioxide sequestration and shale gas production.
KAUST Department:
Computational Transport Phenomena Lab; Physical Sciences and Engineering (PSE) Division
Citation:
Yang Y, Narayanan Nair AK, Sun S (2017) Molecular Dynamics Simulation Study of Carbon Dioxide, Methane, and Their Mixture in the Presence of Brine. The Journal of Physical Chemistry B. Available: http://dx.doi.org/10.1021/acs.jpcb.7b08118.
Publisher:
American Chemical Society (ACS)
Journal:
The Journal of Physical Chemistry B
Issue Date:
3-Oct-2017
DOI:
10.1021/acs.jpcb.7b08118
Type:
Article
ISSN:
1520-6106; 1520-5207
Sponsors:
The research reported in this publication was supported by funding from King Abdullah University of Science and Technology (KAUST), Kingdom of Saudi Arabia. Y.Y. and A.K.N.N. gratefully acknowledge computational facilities provided at KAUST.
Additional Links:
http://pubs.acs.org/doi/abs/10.1021/acs.jpcb.7b08118
Appears in Collections:
Articles; Physical Sciences and Engineering (PSE) Division; Computational Transport Phenomena Lab

Full metadata record

DC FieldValue Language
dc.contributor.authorYang, Yafanen
dc.contributor.authorNair, Arun Kumar Narayananen
dc.contributor.authorSun, Shuyuen
dc.date.accessioned2017-10-11T08:55:11Z-
dc.date.available2017-10-11T08:55:11Z-
dc.date.issued2017-10-03en
dc.identifier.citationYang Y, Narayanan Nair AK, Sun S (2017) Molecular Dynamics Simulation Study of Carbon Dioxide, Methane, and Their Mixture in the Presence of Brine. The Journal of Physical Chemistry B. Available: http://dx.doi.org/10.1021/acs.jpcb.7b08118.en
dc.identifier.issn1520-6106en
dc.identifier.issn1520-5207en
dc.identifier.doi10.1021/acs.jpcb.7b08118en
dc.identifier.urihttp://hdl.handle.net/10754/625849-
dc.description.abstractWe perform molecular dynamics simulation study of CO2, methane, and their mixture in the presence of brine over a broad range of temperature (311–473 K), pressure (up to about 100 MPa), and NaCl concentration (up to about 14 wt %). The general decrease in the interfacial tension (IFT) values of the CH4–brine system with pressure and temperature is similar to that obtained for the corresponding CH4–water system. The IFT of methane and brine is a linearly increasing function of salt concentration, and the resulting slopes are dependent on the pressure. A similar behavior as methane is observed for such systems containing CO2 and CO2–CH4 mixture. The IFT of CO2 and brine increases linearly with increasing salt content; however, the resulting slopes are independent of pressure. The simulations show that the presence of CO2 decreases the IFT values of the CH4–water and CH4–brine systems, but the degree of reduction depends on the amount of CO2 in each sample, which is consistent with experimental evidence. These IFT values show a linear correlation with the amount of CO2, and the resulting slopes are dependent on the temperature and pressure. Furthermore, our results for the mole fractions of the different species in the CO2–CH4–water system at 323 K and 9 MPa are in agreement with those of experiments. The mole fractions of methane and CO2 in the water-rich phase decrease with increasing salt concentration, whereas that of H2O in the methane- or CO2-rich phases remains almost unaffected in all of the studied cases. Our results could be useful because of the importance of carbon dioxide sequestration and shale gas production.en
dc.description.sponsorshipThe research reported in this publication was supported by funding from King Abdullah University of Science and Technology (KAUST), Kingdom of Saudi Arabia. Y.Y. and A.K.N.N. gratefully acknowledge computational facilities provided at KAUST.en
dc.publisherAmerican Chemical Society (ACS)en
dc.relation.urlhttp://pubs.acs.org/doi/abs/10.1021/acs.jpcb.7b08118en
dc.rightsThis document is the Accepted Manuscript version of a Published Work that appeared in final form in The Journal of Physical Chemistry B, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/acs.jpcb.7b08118.en
dc.titleMolecular Dynamics Simulation Study of Carbon Dioxide, Methane, and Their Mixture in the Presence of Brineen
dc.typeArticleen
dc.contributor.departmentComputational Transport Phenomena Laben
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.identifier.journalThe Journal of Physical Chemistry Ben
dc.eprint.versionPost-printen
kaust.authorYang, Yafanen
kaust.authorNair, Arun Kumar Narayananen
kaust.authorSun, Shuyuen
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