(479c) Molecular Simulation of Arsenic Adsorption in Layered Double Hydroxides

The maximum contaminant level for arsenic in drinking water in Europe, Japan, and the USA is very low. As a result, there is increased need for arsenic removal processes suitable for treating water sources. Adsorption processes using layered double hydroxides (LDHs) materials have proven very promising. The LDHs constitute an important class of nanoporous materials with a well-defined layered structure and nanometer (0.3 ~ 3 nm) interlayer separations. They contain certain important functional groups, and consist of two types of metallic cations that are accommodated by a variety of anions in a positively-charged brucite-like layer. Water and the anions are distributed in the interlayer space for charge compensation.

We develop a molecular model of these materials using energy minimization and molecular dynamics (MD) simulation. The model is then used for simulating adsorption of arsenics from an aqueous solution. The results are compared with the experimental date.