Synthesis of pillared clays containing Al, Al-Fe or Al-Ce-Fe from a bentonite: Characterization and catalytic activity

A Colombian bentonite was successfully pillared with solutions of Al, Al-Fe or Al-Ce-Fe polyhydroxocations under moderate conditions of synthesis in order to obtain active catalysts for the wet peroxide oxidation of organic pollutants from industrial wastewaters. The catalysts were very efficient in the phenol oxidation reaction in diluted aqueous medium under mild experimental conditions (298 K and atmospheric pressure). The addition of Ce in the synthesis step of the inorganic polycations yielded a favorable effect in the pillaring of the materials allowing the increase of the basal spacing and enhancing the catalytic activity of the solids. Besides, the characterization by TEM, EPR and chemical analysis techniques confirms the nanocluster formation of iron species, while no evidence of mixed pillars with isomorphic substitution of Fe for Al was obtained.