Catalytic wet peroxide oxidation of phenol by pillared clays containing Al–Ce–Fe

A Colombian bentonite was successfully pillared with mixed polyhydroxocationic solutions of Al–Fe or Al–Ce–Fe, with the iron in small quantities, to generate a modified Fenton process on the surface of the pillared clays with a possible activation of the hydrogen peroxide and the organic substances on the iron sites of the solids in order to obtain active and stable catalysts for the wet peroxide oxidation of organic pollutants from industrial wastewaters. The catalysts were very efficient in the reaction of phenol oxidation in diluted aqueous media under mild experimental conditions (298 K and atmospheric pressure) and in the elimination of the different intermediary compounds of the reaction reaching high-mineralization levels. The solids showed high stability in the reaction media due to the strong interaction between the iron species and the catalyst support. The incorporation of Ce in the solids showed a favorable effect in the pillaring of the materials allowing the increase of the basal spacing and enhancing the catalytic activity of the solids.