abstract |
Nitrogen oxides are removed from gas mixtures containing nitrogen oxides and oxygen by adding a reducing agent that is a C2 to C6 olefin or an aromatic hydrocarbon such as benzene or toluene, preferably butene-1, and contacting the mixture at 200 DEG to 450 DEG C with a catalyst comprising iridium or a compound thereof supported on a refractory carrier, preferably alumina. |