TY - JOUR
T1 - Modelling how incorporation of divalent cations affects calcite wettability-implications for biomineralisation and oil recovery
AU - Andersson, M.P.
AU - Dideriksen, K.
AU - Sakuma, H.
AU - Stipp, S.L.S.
N1 - Funding Information:
We acknowledge funding from the Nano-Chalk Venture through the Danish National Advanced Technology Foundation (HTF) and Maersk Oil and Gas A/S, as well as the W-EOR Project, funded by Maersk Oil Research and Technology Centre for studies on calcite surface properties. Access to computing resources was provided by the Danish Center for Scientific Computing (DCSC), which has since changed its name to the Danish e-Infrastructure Cooperation (DeIC). A small contribution came from the EPSRC (Engineering and Physical Sciences Research Council) of the U.K., through the Frame Project, MIB (EP/I001514/1).
PY - 2016/6/29
Y1 - 2016/6/29
N2 - Using density functional theory and geochemical speciation modelling, we predicted how solid-fluid interfacial energy is changed, when divalent cations substitute into a calcite surface. The effect on wettability can be dramatic. Trace metal uptake can impact organic compound adsorption, with effects for example, on the ability of organisms to control crystal growth and our ability to predict the wettability of pore surfaces. Wettability influences how easily an organic phase can be removed from a surface, either organic compounds from contaminated soil or crude oil from a reservoir. In our simulations, transition metals substituted exothermically into calcite and more favourably into sites at the surface than in the bulk, meaning that surface properties are more strongly affected than results from bulk experiments imply. As a result of divalent cation substitution, calcite-fluid interfacial energy is significantly altered, enough to change macroscopic contact angle by tens of degrees. Substitution of Sr, Ba and Pb makes surfaces more hydrophobic. With substitution of Mg and the transition metals, calcite becomes more hydrophilic, weakening organic compound adsorption. For biomineralisation, this provides a switch for turning on and off the activity of organic crystal growth inhibitors, thereby controlling the shape of the associated mineral phase.
AB - Using density functional theory and geochemical speciation modelling, we predicted how solid-fluid interfacial energy is changed, when divalent cations substitute into a calcite surface. The effect on wettability can be dramatic. Trace metal uptake can impact organic compound adsorption, with effects for example, on the ability of organisms to control crystal growth and our ability to predict the wettability of pore surfaces. Wettability influences how easily an organic phase can be removed from a surface, either organic compounds from contaminated soil or crude oil from a reservoir. In our simulations, transition metals substituted exothermically into calcite and more favourably into sites at the surface than in the bulk, meaning that surface properties are more strongly affected than results from bulk experiments imply. As a result of divalent cation substitution, calcite-fluid interfacial energy is significantly altered, enough to change macroscopic contact angle by tens of degrees. Substitution of Sr, Ba and Pb makes surfaces more hydrophobic. With substitution of Mg and the transition metals, calcite becomes more hydrophilic, weakening organic compound adsorption. For biomineralisation, this provides a switch for turning on and off the activity of organic crystal growth inhibitors, thereby controlling the shape of the associated mineral phase.
UR - http://www.scopus.com/inward/record.url?scp=84976640876&partnerID=8YFLogxK
U2 - 10.1038/srep28854
DO - 10.1038/srep28854
M3 - Article
AN - SCOPUS:84976640876
SN - 2045-2322
VL - 6
JO - Scientific Reports
JF - Scientific Reports
M1 - 28854
ER -