ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 30, Number 2
JKCSEZ 30(2)
April 20, 1986 

A new method was proposed to improve removal of nitrogen oxides (NOx) in exhaust gas by the reduction method using ammonia. At the relative humidity of 60%, 50 ppm of NOx was decomposed at the rate of 1% per hour in the reaction chamber. On the other hand, by adding NH3 which was 5 times more concentrated than NOx, the decomposition rate increased to 6% per hour for 50 ppm NOx and 10% per hour for 20ppm NOx. Within the actual exhausted gases, the decomposition rate of NOx reached the maximum 15% per hour because of coexisted reducing gases, such as hydrocarbon and carbon monoxide, and excess humidity containing trace metal ions. In the presence of acidic SO2 gas, the decomposition rate of NOx decreased. The decomposition of NOx seems to be caused by the mist which is added to the system, and NH3 in the mist which reduces NOx.