Arsenate adsorption and desorption kinetics on a Fe(III)-modified montmorillonite

▶ Adsorption-desorption kinetics of arsenate on a Fe(III)-modified montmorillonite is reported. ▶ Fe(III) species are the responsible for arsenate adsorption. ▶ The adsorption takes place in a two-step mechanism. ▶ Adsorption and desorption studies reflect the presence of externally and internally adsorbed arsenate. ▶ Fe(III) species in Fe-M are more efficient in binding arsenate than in ferrihydrite or goethite.