Term: decay time
https://doi.org/10.1351/goldbook.D01544

Definition:
The time on stream during which the rate constant for the catalytic reaction, k, falls to a specified fraction of its original value, often 0.5.

Related Terms:
1) rate constant (http://doi.org/10.1351/goldbook.O04322).

Source: PAC, 1976, 46, 71. 'Manual of Symbols and Terminology for Physicochemical Quantities and Units - Appendix II. Definitions, Terminology and Symbols in Colloid and Surface Chemistry. Part II: Heterogeneous Catalysis' on page 83 (https://doi.org/10.1351/pac197646010071)

Citation: 'decay time' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.D01544

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