| 摘要 |
PURPOSE:To provide an exhaustion gas cleaning catalyst having treated with phosphorus poisoning prevention by coating in advance on the catalyst surface a glassification-preventive metal oxide in amount exceeding the upper limit to which P2O5 deposited on the catalyst surface can be galssified. CONSTITUTION:In engine exhaustion gas cleaning catalyst, the ratio of glassification preventive metal oxide to P2O5 deposited on the catalyst surface is specified to exceed the upper limit to which P2O5 can be glassified. Such amount is preliminarily coated on the catalyst surface as a means for preventing the catalyst from phosphorus poisoning when preparing an exhaustion gas cleaning catalyst. As such glassification preventive metal oxide, 1 liter of catalyst uses about 1-100g, pref. 1-30g of ZnO, or about 1-70g, pref. 1-20g of CaO, about 0.5-50g, pref. 1-20g of MgO, about 2-200g, pref. 2-60g of BaO. |
