Uses of alumina catalyst carriers

Uses of alumina catalyst carriers
① Loading catalytic active components. Alumina with a small specific surface area (or materials with only a small amount of coarse pores) is usually used to load catalyst active components with high specific activity. This type of carrier can eliminate the diffusion effect in the pores, and in the process for the purpose of selective oxidation, it can reduce the deep oxidation side reactions. For example, the silver catalyst used in the oxidation of ethylene to produce ethylene oxide uses α-alumina as a carrier. Alumina with a large specific surface area has a developed pore structure, which can make the loaded catalyst active components highly dispersed into particles, and with the help of the barrier effect of the carrier, it can prevent the active component particles from sintering and growing during use. It is a widely used alumina carrier. For example, precious metals such as palladium, platinum, and rhodium are dispersed on alumina carriers to make hydrogenation catalysts, which can improve the utilization rate of precious metals.
② The surface acidity of alumina and the loaded active components constitute a dual-function catalyst. For example, the platinum-alumina catalyst used in platinum reforming, in which alumina is both a carrier and one of the catalyst active components.