Investigations of Selective Interactions of the Iron/Aqueous Sodium Chloride System. Part 1. The Adsorption of Chloride Ion by Alpha-Iron(III) Oxide in Sodium Chloride Solutions Saturated by Oxygen at 30C

摘要

A radioisotope procedure was used to investigate the chloride ion adsorption characteristics of crystalline alpha-iron (III) oxide in dilute sodium chloride (36 Cl-labeled) solutions at 30C. The adsorption of the chloride ion was found to be pH dependent, i.e., hydroxyl ions in solution also competed for the active sites on hydrated alpha-iron (III) oxide surfaces. The chloride ion was preferentially adsorbed in the solution pH range of approximately 2 to 4, while hydroxyl ion adsorption was favored in the pH range above 4 to approximately 9. Only a small fraction of the total surface area determined by the BET method was found active for chloride adsorption in an acid environment. (Author)