Conversion of NO to NO₂ in air by a micro electric NO _x converter based on a corona discharge process

A micro-electric-NO_x-converter based on volume treatment is proposed for the evaluation of NO_x concentrations in air. It can electrically convert NO_x mixture from variable mixing rates into a fixed-mixing rate of 25% NO₂ and 75% NO using the corona discharge process with stable conversion efficiency and high throughput (space velocity = 6.3 × 10⁴ h^-1). The micro-electric-NO _x-converter is based on a volume process. Applying high voltage to the electrodes of the micro-electric-NO_x-converter generates a corona discharge. This discharge creates high-energy electrons, which collide with gas molecules. After these collisions, NO and O₂ are broken into single atoms, and they are re-combined as a balanced form, NO₂ in this case. The fabricated micro-electric-NO_x-converter converted NO into NO₂ at conversion efficiency of 25.63%, when 5.5 kV (the applied corona power = 0.196 W) was applied to the micro-electric-NO_x- converter.