| 摘要 |
PURPOSE:To decrease the reproduction frequency of a catalyst by supporting the catalyst component onto a honeycomb carrier made of cordierite and regulating to >=0.20mg/cm<2> the supporting amt. of platinum in the catalyst component per apparent surface area. CONSTITUTION:Platinum acting as catalyst component is supported onto the honeycomb carrier made of cordierite in the amt. of >=0.20mg/cm<2> per the apparent surface area of catalyst in the waste gas. In this case, if the supporting amt. of platinum is decreased to <0.2mg/cm<2>, 5% deterioration time of the catalyst is suddenly shortened, especially the reproduction frequency of the catalyst at <=390 deg.C is suddenly increased, the operation becomes impossible. In addition, the preferable supporting amt. of platinum is 0.24-0.45mg/cm<2>, even at 360 deg.C low temp. and after lapse of 10hr, the >=50% CO-oxidizing ratio is still maintained, 5% deterioration time is also >=5hr and the frequency of catalyst-contrarotating period is remarkably decreased. |
