Effect of Coexisting Gases on NO Removal Using Corona Discharge

Abstract

Effects of H 2 O, CO 2 , CH 4 and C 2 H 4 contained in automotive exhaust gas on NO removal by using a DC corona discharge were investigated experimentally. In this experiment, N 2 /O 2 /NO mixture was used as a base gas of the simulated exhaust gas. To clarify the effect of the individual coexisting gas on NO removal, each coexisting gas was added to the base gas. The results showed that the existence of H 2 O or C 2 H 4 was effective for NO removal with low energy density. Also, when negative corona discharge was applied to the simulated exhaust gas (N 2 /O 2 /NO/H 2 O/CO 2 /C 2 H 4 mixture), the efficiency of DeNOx was more than 90%. However, the by-products such as CO, O 3 , HNO 3 and N 2 O increased with increasing the energy density. It was found that the optimum energy density of corona discharge was about 250 J/L for DeNO x of simulated exhaust gas.