Immobilization of arsenic as scorodite by a thermoacidophilic mixed culture via As(III)-catalyzed oxidation with activated carbon.

In this study we describe the immobilization of arsenic as scorodite (FeAsO.2HO) by a thermophilic iron-oxidizing mixed culture from an acidic sulfate medium containing 500 mg L of Fe(II), 500 mg L As(III) and granular activated carbon (GAC) as the main arsenite oxidant. This study shows that crystalline scorodite can only be precipitated in the presence of the ferrous iron-oxidizing mixed culture (pH 1.