Al,Fe-pillared clays in catalytic decolorization of aqueous tartrazine solutions

In this work Al,Fe-pillared clays (PILCs) were applied as heterogeneous catalysts in catalytic wet peroxide oxidation of tartrazine azo-dye in water. A series of Al,Fe PILCs with different Fe3 + content were synthesized. The degree of Fe incorporation into PILCs was in accordance with the amounts of introduced Fe. The influence of Fe content and reaction temperature on the efficiency of the decolorization of tartrazine solutions was investigated. The adsorption on PILCs was almost independent on temperature and rather inefficient. The adsorption slightly increased with increasing Fe3 + content. Simultaneous application of H2O2 and the Fe-containing PILCs significantly improved dye removal. Higher Fe content led to more efficient catalytic removal of the dye. Increased temperature did not affect adsorption while it drastically increased the catalytic removal of the dye. The stability and reusability of the PILC catalysts was confirmed.

► Al,Fe-pillared clays as catalysts in the Catalytic Wet Peroxide Oxidation.
► Heterogeneous catalysts for peroxide assisted oxidative degradation of azo-dyes.
► Increased Fe content and temperature increase catalyst activity.
► Al nad Fe leaching below 0.01 ppm.
► Catalyst activity retained in repeated tests.