| 摘要 |
Catalyst for use in gas streams contg. O2 and SO2 (esp. for oxidn. of CO and hydrocarbons in IC-engine exhaust gases) have a catalytically active phase comprising a mixt. of alloy of Rh and Pt with an Rh content of =25 (pref. 5-20, esp. 7.5) wt. %. The active phase can be supported on a pelleted or monolithic support, esp. wash-coated with an alkaline suspension (pH >8) of a refractory oxide. Suitable monolithic supports comprise zircon-mullite, mullite, gamma-alumina, sillimanite, Mg silicate, Zr petalite, spodumene, cordierite and aluminosilicates. Suitable pelleted supports comprise charcoal, carbon black, alumina, aluminosilicates, MgO, diatomaceous earth, bauxite, TiO2, ZrO2, limestone, Mg silicate and SIc. Suitable wash coats comprise oxides of B, Al, Si, Be, Mg, Ca, Sr, Ba, Sc, Y, ti, Zr, Hf, Th and/or lanthamides and/or actinides. The catalysts catalyse the oxidn. of CO and hydrocarbons more readily than the oxidn. of SO2, so that SO3 emission is minimised. |
