VAPOR-PHASE DEEP OXIDATION OF CHLORINATED HYDROCARBONS CATALYZED BY PILLARED BENTONITES

A natural sodium bentonite was pillared with aluminum, aluminum-iron, aluminum-ruthenium and aluminum-chromium polyoxocations. The clays were characterized by X-ray diffraction, ESCA and nitrogen adsorption. All the clays resulted to varying degrees in active catalyst for the deep oxidation of volatile chlorinated hydrocarbons (CVOCs) in the 300-400 degrees C temperature range. The chromium pillared clay was by far the most active and stable catalyst, with more than 99% hydrocarbon conversion at 300 degrees C. The catalytic activity trend is discussed as a function of the Bronsted acidity and of the oxidizing power of the metallic couple.