Experimental investigation on the effect of a microsecond pulse and a nanosecond pulse on NO removal using a pulsed DBD with catalytic materials

In this study, an experimental investigation of the removal of NO from an atmospheric air stream has been carried out with a non-thermal plasma dielectric barrier discharge reactor filled with different catalytic materials. TiO2, CuO–MnO2–TiO2, CuO–MnO2–Al2O3 catalysts were used to study the synergy between the plasma and the catalysts. The NOx removal efficiency and by-products formation were studied as a function of energy density, pulse rise time and width using a plasma catalytic configuration. It was observed that the shorter pulses are more efficient for NOx removal but at the expense of higher by-products formation such as N2O and O3. A comparison has been made between an in-plasma catalytic configuration and a post-plasma catalytic configuration. Among all the three catalysts that were studied, CuO–MnO2–TiO2 catalyst showed the best performance with respect to the removal efficiency as well as the by-products formation in both the in-plasma and the post-plasma catalytic configuration. In general, the post-plasma configuration showed better results with respect to low by-products formation.