摘要 |
A catalyst comprises (a) an activated alumina, (b) a substantially water-insoluble bulk stabilizer present in an amount at least sufficient to stabilize the activated alumina against thermal degradation, and (c) one or more platinum group metal catalytic components. The bulk stabilizer may be one or more of calcium sulfate, strontium sulfate or, preferably, barium sulfate. A mixture of activated alumina (and/or activated alumina precursor) and bulk stabilizer particles, e.g., gamma-alumina particles and barium sulfate particles, may be slurried in an aqueous medium and coated onto a carrier substrate. One or more platinum group metal catalytic components may be dispersed onto the activated alumina, e.g., it may be dispersed onto a mixture of activated alumina and bulk stabilizer. The coated carrier substrate may be calcined in air to provide the catalyst. |