The ability of an iron-impregnated ion exchange bead (PWX5) to remove As(V) from ground water was investigated. The effects of particle size, solution pH, As(V) concentration, competition, adsorbent concentration, temperature, iron content, and iron accessibility on removal kinetics and/or equilibrium were determined. PWX5’s performance was compared to other iron-based adsorbents, primarily Bayoxide^® E-33 (E-33) a granular ferric oxide, for arsenic removal performance. All of the factors cited impacted either the amount of As(V) adsorbed or the rate of adsorption. Stirred batch reactor data showed the rate of adsorption increased as particle size decreased and bottle point isotherm data showed As(V) adsorption maximum capacity increased with higher initial adsorbate concentration. The presence of phosphate and silicate reduced the amount of As(V) adsorbed as did a pH > 7.0. PWX5 is durable, rather homogeneous in size and effective at removing As(V). It is a viable alternative to E-33 which wears more easily.

Key words. Arsenic removal, drinking water, anion ligand exchange, adsorption, particle size, granular ferric oxide, iron impregnation.