Intensification of NOx absorption process by means of ozone injection into exhaust gas stream

The growing emissions of nitrogen oxides into atmosphere endanger the human health and degrade our environment. In this work the application of ozone for the oxidation of nitrogen oxides present in exhaust gases was described. The main concept of the process is to oxidize nitrogen monoxide (NO) and nitrogen dioxide (NO2) into dinitrogen pentoxide (N2O5) which reacts with water giving nitric acid. This way nitrogen oxides (NOx) can be absorbed in water with good effectiveness. In presented studies we investigated the influence of the NO initial concentration and the ratio of NO/NO2 in reaction gases on the NO conversion and selectivities into products. Furthermore, the two stage process composed of NOx ozonation and the subsequent absorption of reaction gases in the 0.01 M solution of NaOH was performed. This experiments proved that due to ozonation the efficiency of NOx absorption process is much higher than without ozone injection.

► Influence of nitric oxide initial concentration on the effectiveness of ozonation process.
► Influence of nitric oxide to nitrogen dioxide ratio on the effectiveness of ozonation process.
► Nitrogen oxides emission abatement with the use of ozonation and subsequent absorption of reaction gases.