Abstract: An apparatus and a method for removing pollutants from gas streams using a reactor assembly. The reactor assembly includes an inlet, an outlet, at least two electrodes, a catalyst bed, and plasma generated from the electrodes. Electrical energy is applied, and catalytic surfaces enhanced by the plasma results in the reduction of NOx to N2 and oxidation of particulates and hydrocarbons to CO2. Furthermore, the present invention removes NOx, particulate, and hydrocarbons from O2 rich pollutant streams without the need for supplemental additives.