Heterogeneous TiO2-Fe-plate catalyst for the discoloration and mineralization of aqueous solutions of cationic and anionic dyes

A novel structured TiO2-Fe-plate catalyst was prepared by immobilization of iron and TiO2 on a natural clay plate. This catalytic system allows effective mineralization of wastewaters under a wide range of operation conditions. Upon UVA irradiation and in the presence of several oxidant mixtures (H2O2 or/and K2S2O8), this catalyst was found to be highly effective in the mineralization of malachite green and red congo in water solution. The effectiveness of this catalyst was assigned to a synergy between its photo-catalytic and photo-Fenton activities. Activity was enhanced in the presence of small amounts of K2S2O8 and verified over a wide range of pH.