Arsenic and antimony removal from drinking water by adsorption on granular ferric oxide

Abstract

Arsenic and antimony occur in drinking water due to natural weathering or anthropogenic activities. There has been growing concern about their impact on health. The aim of this study was to assess the efficiency of a granular ferric oxide adsorbent medium to remove arsenic and antimony from drinking water via rapid small-scale column tests (RSSCTs). Three different water matrices – deionized, raw water treated with a reverse osmosis domestic device and raw water – were spiked with arsenic and/or antimony to a concentration of 100 μg L−1. Both elements were successfully adsorbed onto the medium. The loadings until the guideline value was exceeded in the effluent were found to be 0.35–1.63 mg g−1 for arsenic and 0.12–2.11 mg g−1 for antimony, depending on the water matrix. Adsorption of one element was not substantially affected by the presence of the other. Aeration did not affect significantly the adsorption capacity. Granular ferric oxide could be employed for the simultaneous removal of arsenic and antimony from drinking water, whereas full-scale systems should be assessed via laboratory tests before their implementation.