Cobalt-exchanged natural zeolite catalysts for catalytic oxidation of phenolic contaminants in aqueous solutions

Indonesia (IZ) and Australia (AZ) natural zeolites were employed to prepare cobalt exchanged catalysts. Characterization tests of scanning electron microscopy (SEM), X-ray diffraction (XRD) and Brunaeuer-Emmet-Teller (BET) were used for performing sample analyses. The efficiencies of phenol removal on the catalysts were evaluated by the catalytic oxidation of phenol with sulfate radicals. Cobalt-exchanged catalysts showed higher phenol removal efficiencies than adsorption, Oxone self-oxidation and unmodified zeolites. The reactions were observed to be more efficiently described by the zero-order kinetics, while the respective Co/IZ and Co/AZ activation energies were 44.1 and 59.5. This study provides a novel application of low-cost natural zeolites for environmental remediation.