Molecular Simulation of the Adsorption of Seawater Salts on a Negatively Charged Quartz Surface
Molecular dynamics simulations of the (1001) surface of α-quartz interacting with aqueous solutions of different seawater salts are performed with the CLAYFF force field modified to describe the negative charging of the quartz surface. Results include cation density profiles and adsorption maps on the quartz surface. Results are compared with literature data. The adsorbed amount of cations decreases as the cation valence increases. For a series with the same valence the adsorbed amount decreases as the size of the bare cation increases, except for Li and Mg, and presumably Al. The latter cations are absorbed in their hydrated form with their hydration layers almost intact.
Index Termsó Adsorption, Seawater, Force field, Molecular simulation.