— substance or material, which, through repeated cycles of elementary steps, accelerates conversion of reagents into reaction products; the catalyst is regenerated to its original state at the end of each cycle during the entire lifetime.
Catalysts are classified into homogeneous catalysts, which are in phase with the reagents (e.g. acids and bases, metal complexes, etc.), and heterogeneous catalysts, which are separated from the reactants by an interface (e.g. metals, metal oxides, etc.). The intermediate position is occupied by microheterogeneous catalysts, which include colloidal or polymeric particles, including biocatalysts (enzymes)
. The main characteristics of the catalysts are their activity and selectivity; in addition, they vary in heat resistance, mechanical strength (for heterogeneous systems), stability, resistance to catalyst poisons and other parameters.
- Smirnov Andrey V.
- Tolkachev Nikolay N.
- Romanovsky Boris V.
- Boudart M. Perspectives in Catalysis (Eds: J. M. Thomas, K. I. Zamaraev)- Blackwell, Oxford, 1992- p.183.
- Krylov O.V. Heterogeneous Catalysis. Textbook (in Russian) // M. PTC "Akademkniga", 2004. - 679 pp.,