Catalyst for reducing nitrogen oxides.

摘要

A catalyst for reducing nitrogen oxides in the exhaust gas with ammonium, having a catalyst composition coated on an inorganic fiber cloth as a substrate is provided. The inorganic fiber cloth is impregnated with at least one inorganic oxide selected from silica and said catalyst composition, preferably with an organic binder like polyvinyl alcohol, so that the weight ratio of the inorganic oxide/said inorganic fiber cloth is in the range of 0.05 to 0.8 and the inorganic oxide is substantially placed between the fibers constituting said inorganic fiber cloth. The above inorganic fiber cloth is preferably a glass fiber cloth, more preferably a glass fiber cloth which surface is acid-treated to have a layer deficient in alumina and calcium oxide.