Term: crowding
https://doi.org/10.1351/goldbook.C01420

Definition:
The displacement of an impurity from an extract phase by contact with a solution containing the main extractable solute. The main solute need not be present in a pure solution but should have a higher distribution ratio than the impurities present.

Related Terms:
1) exchange extraction (http://doi.org/10.1351/goldbook.E02239).
2) scrubbing (<em>in solvent extration, in atmospheric chemistry</em>) (http://doi.org/10.1351/goldbook.S05511).

Source: PAC, 1993, 65, 2373. 'Nomenclature for liquid-liquid distribution (solvent extraction) (IUPAC Recommendations 1993)' on page 2386 (https://doi.org/10.1351/pac199365112373)

Citation: 'crowding' 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.C01420

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