Method for Coating Filter Media with Synthetic Manganese Oxide

Abstract

A method was developed to coat anthracite and sand filter media with synthetic manganese oxides. The two-stage method used a stirred tank reactor followed by a recirculating flow fixed-bed reactor. Treated anthracite developed encapsulating coatings of manganese oxides up to 30-μm thick, at loadings over 4 mg/g−1 extractable Mn2+. Media were characterized by BET surface area analysis and electron microscopy. Laboratory-scale column tests confirmed the efficient Mn-removal capability of the synthetically coated media in adsorption and oxidation modes. This method may help improve the removal of Mn2+ from drinking water and hazardous effluents by filtration with oxide-coated media.