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

Weixuan Zhao,Huiqi Hou,Gang Luo,Renxi Zhang,Ruina Zhang,Yanghaichao Liu,Heng Wei,Shanping Chen

doi:10.3390/app9132751

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.

Highlights

Nitrogen oxide (NOX ) emissions from fossil fuel combustion are one of the primary air pollutants, inducing various environmental problems, such as secondary aerosols and tropospheric ozone [1,2,3,4].the abatement of NOX is one of the most extensively studied fields in the history of environmental science
NH3 –Selective catalytic reduction (SCR) assisted by dielectric barrier discharge (DBD) can enhance the NOX conversion when CH4 is used as an assistant by DBD can(below enhance
NOXOconversion when CH4 is used as an assistant reducing agent assisted at low temperatures

Summary

Introduction

Nitrogen oxide (NOX ) emissions from fossil fuel combustion are one of the primary air pollutants, inducing various environmental problems, such as secondary aerosols and tropospheric ozone [1,2,3,4].the abatement of NOX is one of the most extensively studied fields in the history of environmental science. Selective catalytic reduction (SCR) is regarded as a practical method for the removal of NOx, which is highly efficient and environmentally friendly compared to other denitration methods. Promising catalysts for NOX reduction, such as Ag/Al2 O3 [5,6,7,8,9,10,11,12,13] and Ce/Fe–ZSM-5 [14,15,16,17,18], have sufficient activity when the temperature exceeds 673 K. The V2 O5 –WO3 /TiO2 [19,20,21,22,23,24,25,26,27] catalyst can achieve superior activity only when the temperature is between 573 K and 673 K.

Methods

Results

Conclusion