A catalyst carrier (support) is a low-activity or inert material, which serves to stabilize the particles of the catalytic active phase on its surface.
The catalyst carrier can be used in the form of natural (various clays, asbestos, pumice, diatomite) or synthetic materials (oxides of aluminium, zirconium or magnesium, silica gel, activated carbons, aluminosilicates).
Functions of Catalyst Carriers
The function of carriers in heterogenous catalysis is to prevent the sintering or agglomeration of the active component to maintain the required area of contact between the agents and the active substance. The amount of the catalyst carrier is generally greater than the amount of the primary active component applied onto it.
The principal requirements for catalyst carriers include a large surface area, thermal stability, porosity, chemical inertness and increased mechanical strength. In some cases, catalyst carriers affect the active phase performance, that is the effect of a strong interaction between the metal and the carrier is observed.
Types of Catalyst Carriers
Most often, ceramic materials serve as a base for application of various types of industrial catalysts. It is allowed to use ceramic carriers at elevated temperatures, this is why, in many cases, it is an adequate solution to the process tasks assigned.
Wide-spread types of catalyst carriers are as follows:
- cellular-type carriers in various sizes and forms;
- cellular-type carriers with a large number of holes: they are used for the afterburning of produced exhaust gases in case of using internal combustion engines;
- porous ceramic granulates are bulk-type carriers with diversiform individual particles (petal-shaped, cylindrical and others);
- porous ceramic granulates, used for catalytic filter medium, which is necessary for decomposition of active residual chlorine into chloride ions and high-reactivity atomic oxygen: these materials are suitable for integrated sewage treatment and water dechlorination in circulating and industrial water supply systems.
The well-developed carrier surface ensures an impressive increase in the efficiency of agent transformation in various chemical processes. Bulk-type catalyst carriers, having well-developed surfaces, are characterized by numerous internal openings and a regular geometry of the carrier. Well-developed surfaces of granular carriers appear due to small granule sizes and an open porous structure.
Microintech produces catalyst carriers according to our customers’ requirements, specified for the type of surface, geometry and physical and mechanical properties needed.