An experimental study on photochemical effect of UV light on NOx decompositions

Effective decomposition methods of nitric oxides (NO_x) in combustion exhaust gases are required in industrial fields. In this work, the photochemical effect of ultraviolet light on NO_x decompositions is experimentally investigated. The relative high-energy photons dissociate from a molecular NO to N and O atoms. The photochemical dissociated O atom unites with the NO molecule and the resultant NO₂ molecules are produced. By the same token, the photochemical dissociated N atom unites with other N atom and the N₂ molecules are produced. As the result, the NO concentrations decrease with above photochemical reactions. The experiments are conducted by using ultraviolet light of an excimer radiation lamp. The NO, NO₂, and NO_x concentrations are measured by a Fourier transform infrared spectrometer (FT-IR) and a NO_x analyzer. The experimental results show the decreased NO_x characteristics from the photochemical reactions. The photochemical effect based on the experimental results is discussed in terms of NO removal efficiency.