Release Time:2019-03-13  Hits:

Indexed by: Journal Article

Date of Publication: 2016-10-17

Journal: MOLECULAR PHYSICS

Included Journals: Scopus、EI、SCIE

Volume: 114

Issue: 20

Page Number: 2924-2935

ISSN: 0026-8976

Key Words: Molecular dynamics simulation; hydrogen bonds; CO2 sequestration

Abstract: To investigate the effects of sequestration condition on hydrogen bonds between mineral and water, molecular dynamics simulations have been performed. The simulations were conducted at conditions related with geologic sequestration sites: pressure (3.1-32.6 MPa), temperature (318 and 383 K), salinity (0-3 M), salt (NaCI and CaCl2) and silica surface models Q(2) (geminal), Q(3) (isolated) and amorphous Q(3). The hydrogen bonds were classified into four types: silica-silica, silica-dissolved CO2, silica-water as donors and silica-water as acceptors. The mean numbers of hydrogen bonds for each type were analysed. The results show that: (1) silica surface silanol groups do not form H-bonds with dissolved CO2 molecules in water (brine); (2) The mean number of hydrogen bonds between silanol groups follows the order: Q(2) > amorphous Q(3) > Q(3); (3) The mean number of hydrogen bonds between silanol and water molecules follows the order: Q(3) > amorphous Q(3) > Q(2).