Field pilot evaluations of iron oxide‐based arsenic adsorption media

Abstract

Field pilot tests were conducted with three hybrid adsorptive media to evaluate their performance at removing arsenic from groundwater. The media are based on polymeric resins loaded with iron oxyhydroxide nanoparticles and were evaluated with a commercially available granular ferric oxide media as a reference material at well sites in New Hampshire and Arizona. A full‐scale arsenic removal system in Connecticut is also discussed. The water chemistries of these three locations varied in terms of pH, arsenic concentration and speciation, and silica and phosphate content. Although all media were hybrid iron oxide materials, they exhibited different levels of performance and capacity under the specific pilot conditions because the effective operational life to remove arsenic is dependent on the chemistry of the treated water as well as the porosity of the base resin. The availability of the iron phase for arsenic binding is an important parameter, particularly in dynamic column applications.