To broaden and lower the temperature window of the selective non catalytic reduction (SNCR) of nitric oxide (NO), the use of activated ammonia as the reduction agent was examined. A xenon excimer lamp emitting a wavelength of 172 nm (vacuum ultraviolet
VUV) was employed as the excitation source of molecular ammonia. The effects of oxygen concentrations and pipe length for ammonia injection on NO removal were investigated for application of commercial processes. Chemical composition of activated ammonia was analyzed to investigate effective chemical species for deNOx. © 2013 The Japan Society of Mechanical Engineers.