The nanoscience and nanotechnology have brought with new chance for new applications of some traditional pollution treatment technology. A port of new instance, in a rare earth doped cerium oxide nanopowder was used as a catalyst to investigate the removal of color and TOC from simulated wastewater of C.I. Reactive Blue 198. Graphite electrode was used as anode and cathode and electrolysis were carried out in presence of an electrolyte NaCI with a catalyst concentration of 50 mg/L at a constant current density of 34.96 mA/cm². In order to find the efficiency of nanocatalyst, experiments were also conducted without catalyst. From the experiment, it was found that complete color removal was achieved on electrocatalytic oxidation as well as electro oxidation process. When comparing the above processes, catalytic oxidation shows more efficiency than electro oxidation. Under the same experimental condition the removal of TOC was found to be 24% for electro oxidation and 46% for electro catalytic oxidation. It infers that even though the electro-catalytic oxidation process achieves complete decolorization but it does not achieve complete mineralization. The UV-visible spectrum confirms the decolorization and FTIR studies confirmed the changes in the functional groups after treatment.

Key words: Electrocatalytic oxidation; Reactive Blue 198; Sm³⁺ Doped cerium oxide; Graphite electrode; Color removal.