NO Removal by Plasma-Enhanced NH₃-SCR Using Methane as an Assistant Reduction Agent at Low Temperature

Abstract

The effects of using CH4 as an assistant reduction agent in plasma-assisted NH3−SCR were investigated. The new hybrid reaction system performed better than DBD−NH3−SCR when the O2 concentration varied from 2% to 12%. Compared with DBD−NH3−SCR, DBD−NH3−CH4−SCR (NH3:CH4 = 1:1) showed a more significant promotion effect on the performance and N2 selectivity for NOX abatement. When the O2 concentration was 6% and the SIE was 512 J/L, the NO removal efficiency of the new hybrid system reached 84.5%. The outlet gas components were observed via FTIR to reveal the decomposition process and its mechanism. This work indicated that CH4, as an assistant agent, enhances DBD−NH3−SCR in excess oxygen to achieve a new process with significantly higher activity at a low temperature (≤348 K) for NOX removal.

Keywords

• dielectric barrier discharge (DBD)
• NO abatement
• assistant reduction agent
• DBD–SCR assisted by CH₄