| 摘要 |
To provide a method for manufacturing a double layer coated Pd-only three-way catalyst, wherein a completed catalyst maintains more improved nitrogen oxide removal performance and heat resistance by high porosity of second coating layer and is capable of greatly reducing a consumption amount of expensive Pd(palladium) compared with an existing manufacturing method. In a method for manufacturing a high porous double layer coated Pd-only three-way catalyst having high durability and high performance by preparing first catalyst slurry and second catalyst slurry using Pd(palladium), alumina, cerium oxide, mixed solution and so on, primarily coating the first catalyst slurry on a ceramic monolith carrier, and secondly coating the second catalyst slurry on the dried and fired ceramic monolith carrier after drying and firing the primarily coated ceramic monolith carrier, the method for manufacturing the double layer coated Pd-only three-way catalyst is characterized in that the second catalyst slurry is prepared by reducing alumina impregnated with a Pd solution, preparing a mixture by mixing cerium oxide, Ce-Zr composite oxide(Ce.Zr)O2, Ce-Zr-Y composite oxide(Ce.Zr.Y)O2 and cerium carbonate(Ce(CO3)2) in a weight ratio of 15:60:15:10 to 15:50:20:15, adding the prepared mixture to the reduced Pd solution impregnated alumina in an amount of 15 to 25 g/L for the total carrier apparent volume, adding praseodymium oxide to the resulting mixture in an amount of 2 to 5 g/L for the total carrier apparent volume, and adding one selected from (LaCe)(FeCo)O3 and (LaSr)(FeCo)O3 that are metal oxide(perovskite) to the mixed solution in an amount of 15 to 25 g/L for the total carrier apparent volume after reacting the mixed solution.
|
