Alumina used as a catalyst carrier can be classified into several types according to its physical and chemical properties and the role it plays in catalysis:
(1) High-Temperature Aluminum Oxide Carrier. This type of aluminum oxide has a small specific surface area, exhibits high-temperature resistance, chemical resistance, and high mechanical strength, thus capable of withstanding harsh operating conditions. Due to its inert nature, the high-temperature aluminum oxide carrier does not act as a potential active source causing side reactions and reduced selectivity, nor does it serve as a potential source of toxicity within the catalyst system.
(2) Interactive Carrier. This type of alumina has a wide range of applications. It reacts with the active components of the catalyst, dispersing the active components within the carrier. This provides the active components with an effective specific surface area and appropriate pore structure, enhancing the catalyst's thermal stability and anti-toxic performance.
(3) Synergistic or dual-functional carrier. This type of alumina, in addition to serving as the framework for the active components, also provides an enhancement effect for the catalyst's catalytic efficiency.
