| 摘要 |
PURPOSE:To obtain a catalyst for converting not only CO and hydrocarbon to CO2 and water but also NO2 to NO in an oxygen remaining atmosphere, by adding an org. acid to a support solution and simultaneously supporting a palladium metal, zirconium oxide and yttrium oxide by the surface of a carrier. CONSTITUTION:An org. acid such as citric acid or oxalic acid is added to a solution mixture of a palladium precursor such as palladium nitrate, a zirconium oxide precursor such as zirconium nitrate and an yttrium oxide precursor such as yttrium chloride in a range of 1:0.5-1:10 on a wt. basis with respect to the total conversion wt. of zirconium oxide and yttrium oxide. A carrier is immersed in this solution to be impregnated therewith and, after drying, the impregnated carrier is subjected to decompositional baking to obtain a catalyst. The mixing ratio of the palladium metal, zirconium oxide and yttrium oxide is 1:5:20-1:20:5 on a wt. basis. This catalyst oxidizes CO and hydrocarbon in combustion exhaust gas in an oxygen-rich atmosphere and converts NO2 to NO which is lower in toxity. |
