Non-Thermal Plasma Assisted Catalytic NOx Remediation from a Lean Model Exhaust

No efficient catalyst presently exists for deNO_x in lean burn conditions. Furthermore, actual catalysts generally deactivate during reaction. A cylindrical DBD non-thermal plasma reactor was coupled with a stable three-function catalyst in order to verify the nature of the effect of the plasma on the catalytic process. A mixture of NO/O₂/C₃H₆ in N₂ was used as a lean model exhaust. The plasma was found to perform two of the three functions: NO oxidation to NO₂ and propene activation through the partial oxidation of the hydrocarbon to aldehyde or alcohol. A complete catalyst containing the first two previous functions and the associative chemisorption of NO (third function) was used, as well as a simplified catalyst containing only the third function. Results suggest an advantageous plasma-catalyst coupling effect on NO_x remediation in accordance with the proposed catalytic model.