Efficient nonthermal plasma degradation of toluene over NiO catalyst with limited NOx generation

A problem encountered during nonthermal plasma destruction of pollutants in gas streams containing air is that high levels of nitrogen oxides may also be formed as a consequence of the complex processing conditions. In the work presented herein, a post nonthermal plasma catalytic system was evaluated for removal of toluene gas. NiO/γ-Al2O3 catalysts with different NiO loadings were prepared via the traditional impregnation method and their activity determined under certain conditions. The effects of the specific input energy (SIE), catalyst calcination temperature, and NiO loading on the toluene degradation were investigated. The catalyst prepared by calcination at 450 °C showed the highest activity. The catalytic activity of the catalysts first increased then decreased with increasing NiO loading, with the maximum toluene conversion of 93 % being achieved by 1.25 wt% NiO/γ-Al2O3 at 200 ppm. Meanwhile, the amount of NOx produced during the reaction was investigated. In the reaction process, a very small amount of NOx was produced, indicating that the catalyst is green and efficient.