Title: pre-equilibrium
Long Title: IUPAC Gold Book - pre-equilibrium
DOI: 10.1351/goldbook.P04809
Status: current

Definition
Preliminary treatment of a solvent in order to convert the extractants into a suitable chemical form.Notes:The use of equilibration in this sense is confusing and should be avoided.The term conditioning may be used as a synonym for pre-equilibration.Preliminary treatment of either phase with a suitable solution of the other phase (in the absence of main extractable solute(s)) so that when the subsequent equilibration is carried out changes in the (volume) phase ratio or in the concentrations of other components are minimized.

Related Term
- equilibration: https://goldbook.iupac.org//terms/view/E02175

Source
- PAC, 1993, 65, 2373. 'Nomenclature for liquid-liquid distribution (solvent extraction) (IUPAC Recommendations 1993)' on page 2378 (https://doi.org/10.1351/pac199365112373)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/P04809/html
- json: https://goldbook.iupac.org/terms/view/P04809/json
- xml: https://goldbook.iupac.org/terms/view/P04809/xml

Citation: Citation: 'pre-equilibrium' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.P04809
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Accessed: 2026-04-18T01:32:42+00:00