What is Catalyst?

Catalysis is the key to chemical reactions. Most industrial syntheses and nearly all biological reactions require catalysts. Catalysts are materials that speed up reactions by providing an alternative pathway for the converting reactants into products. Apart from accelerating reactions, catalysts can influence the selectivity of chemical reactions. This means that completely different products can be obtained from a given starting material by using different catalyst systems.


Classification of Catalysts

Catalysts can be gases, liquids, or solids. Most industrial catalysts are liquids or solids, whereby the latter react only via their surface. The numerous catalysts known today can be classified according to various criteria: structure, composition, area of application, or state of aggregation. There are two large groups: heterogeneous catalysts (solid-state catalysts) and homogeneous. There are also intermediate forms such as homogeneous catalysts attached to solids (supported catalysts), also known as immobilized catalysts.


Catalysts in Industry

Catalysis is a vital technology in the production of almost all useful chemical products. Catalysts have been successfully used in crude-oil processing and petrochemistry, such as purification stages, refining, and chemical transformations. Environmental protection measures such as automobile exhaust control and purification of off-gases from power stations and industrial plant would be inconceivable without catalysts. Catalysis also has become increasingly important for the pharmaceutical industry. The process of catalysis is essential to the modern chemical industry that saves energy and money.