Title: crowding
Long Title: IUPAC Gold Book - crowding
DOI: 10.1351/goldbook.C01420
Status: current

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
- exchange extraction: https://goldbook.iupac.org/terms/view/E02239
- scrubbing: https://goldbook.iupac.org/terms/view/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)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/C01420/html
- json: https://goldbook.iupac.org/terms/view/C01420/json
- xml: https://goldbook.iupac.org/terms/view/C01420/xml

Citation: Citation: 'crowding' 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.C01420
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Accessed: 2026-06-28T14:04:12+00:00