Molecular insights on the influence of temperature and metal ions on the hydration of kaolinite (001) surface
Bingxin Liu, Min Dai, Imran Ali, Shuai Li, Lin Sun, Changsheng Peng, Iffat Naz
Abstract
In the present research, various divalent and monovalent metal salt solutions (NaCl, KCl, MgCl2 and CaCl2) were added into the kaolinite-water system to explore its impact on the surface hydration of kaolinite. The hydration layers’ density and adsorption energy between kaolinite and water molecules were gradually decreased with an increase in temperature from 280 to 330 K. The addition of metal ions had a great influence on the hydration of the kaolinite surface. While the adsorption energy and structure of hydration layers in the kaolinite-water-ion system was unchanged when the ion concentration reaches 0.8 M. The adsorption energy between kaolinite and divalent ions was greater than between kaolinite and monovalent ions.