| Autor: |
Koleini MM; Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran. mmkoleini@che.sharif.edu., Badizad MH; Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran., Mahani H; Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran., Dastjerdi AM; Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran., Ayatollahi S; Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran., Ghazanfari MH; Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran. |
| Abstrakt: |
This paper resolve the salinity-dependent interactions of polar components of crude oil at calcite-brine interface in atomic resolution. Molecular dynamics simulations carried out on the present study showed that ordered water monolayers develop immediate to a calcite substrate in contact with a saline solution. Carboxylic compounds, herein represented by benzoic acid (BA), penetrate into those hydration layers and directly linking to the calcite surface. Through a mechanism termed screening effect, development of hydrogen bonding between -COOH functional groups of BA and carbonate groups is inhibited by formation of a positively-charged Na + layer over CaCO 3 surface. Contrary to the common perception, a sodium-depleted solution potentially intensifies surface adsorption of polar hydrocarbons onto carbonate substrates; thus, shifting wetting characteristic to hydrophobic condition. In the context of enhanced oil recovery, an ion-engineered waterflooding would be more effective than injecting a solely diluted saltwater. |
