Selective non-catalytic reduction of NOx by activated ammonia injection has been developed to broaden and lower the narrow temperature window for de-NOx. A temperature window enlargement of 150 °C was achieved at the lower boundary of the window using activated ammonia injection. Hydrogen is activated ammonia species play an important role in the expansion of the reaction temperature range. The purpose of this research isto find the optimum conditions ofthe H2 / NH3 molar ratio for the development of low temperature SNCR method.The experiment was performed using a mixed gas of NH3 / H2 at a temperature range of 650-750 °C. Optimum H2 / NO molar ratio was decreased with increasing reaction temperature. Optimum H2 / NH3 molar ratio was 0.3 in NH3 / NO = 1.0, reaction temperature 750 °C. MaximumNOx removalwas about 80% in optimal conditions, NH3 / NO = 1.0.
