| 摘要 |
A catalyst suitable for use in the treatment of motor vehicle exhaust emissions is made by contacting a substrate, preferably of an aluminium bearing ferritic alloy, with a first sol of refractory material followed by drying and firing, and preferably then contacting with a second sol of refractory material, which additionally contains a salt convertible to catalytic material, followed by drying and firing. The sols are obtained from refractory material, e.g., alumina, made by a vapor phase condensation method. |
