NO'x treatment by dielectric barrier discharge

We present an experimental technique for decomposing nitrogen oxides by means of chemical processes of oxidation and reduction assisted by electric discharges taking place in a reactor designed for this effect. The plasma reactor consists of two flat aluminium electrodes of circular geometry with gas input and output accesses capable of increasing slightly the turbulence of the gas flux so to homogenize the mixture to be treated. Both electrodes are covered with a dielectric material. During the experimental phase, an N-2 + NO (200 ppm) with slight proportions of 02 (< 1%) gas mixture flows at 1.0 1pm and at room pressure. The discharge voltage is measured with a high voltage probe and a digital storage oscilloscope, while the discharge current is gauged with a current transformer. The consumed power in the cells was experimentally determined through Manley's method. The residual gases were measured by a Sensonic 2000 analyzer. The results showed that, a 12 mJ energy supply and a power of 20 W are enough to degrade up to 99% of the initial amount of NO in a 305 cm(3) reaction volume.