Sorption and surface oxidation of As(Ⅲ) by Fe-oxyhydroxysulfates in acidic medium

摘要

Acute toxicity and bioavailability of arsenic (As) is governed by its redox state in contaminated water and, hence, treatment of As(Ⅲ)-enriched drinking water becomes prime concern due to its higher toxicity and mobility. Fe-oxides remove higher levels of As(Ⅲ) and causes surface oxidation to As(V) (Greenleaf et al., 2003). Schwertmannite, the most common Fe-oxyhydroxysulfate precipitates in acid mine drainage areas, is reported to be a significant natural sink for As(V) (Casiot et al., 2005; Cheng et al., 2009). However, a detailed research evaluating As(Ⅲ) behavior onto schwertmannite (SHM) in acidic medium does not exist so far in our knowledge.