Oxidation of AsIII by several manganese oxide minerals in absence and presence of goethite

Abstract

Abstract Oxidation of AsIII by three types of manganese oxide minerals affected by goethite was investigated by chemical analysis, equilibrium redox, X‐ray diffraction (XRD) and transmission electron microscopy (TEM). Three synthesized Mn oxide minerals of different types, birnessite, todorokite, and hausmannite, could actively oxidize AsIII to AsV, and greatly varied in their oxidation ability. Layer structured birnessite exhibited the highest capacity of AsIII oxidation, followed by the tunnel structured todorokite. Lower oxide hausmannite possessed much low capacity of AsIII oxidation, and released more Mn2+ than birnessite and todorokite during the oxidation. The maximum amount of AsV pr..