| 摘要 |
PURPOSE:To selectively adsorb and decompose NO2 in an exhaust gas by carrying 2-15wt.% of a mixture of copper and niobium oxides in a proportion by molar ratio of 1:1 on the surface of an inorg. heat-resisting material such as alumina, etc., and forming the catalyst. CONSTITUTION:The titled catalyst is formed by carrying 2-15wt.% of the mixture of copper and niobium oxides in the proportion by molar ratio of 1:1 on the surface of the inorg. heat-resisting material such as alumina, silica, cordierite, etc. The stoichiometric proportion of copper to niobium is preferably 1.0-1.5. When NO2 is adsorbed on the obtd. catalyst, the electron is apt to flow into the NO2 molecule from copper carried on the catalyst. The NO2 becomes unstable thereby and decomposes to NO. The NO of its own is not oxidized with oxygen coexisting together and exhausted as it is. Besides, the catalyst has high thermal resistance and its activity is not deteriorated when the catalyst is used for a long time at 800 deg.C. |
