Title: phase volume ratio
Long Title: IUPAC Gold Book - phase volume ratio
DOI: 10.1351/goldbook.16257
Status: current

Definition
Volume of the mobile phase divided by volume of the stationary phase in a column in counter-current chromatography.

Notes
1) The stationary phase volume retention ratio (\(S_{\rm{f}}\)) has been defined as the ratio of the volume of stationary phase (\(V_{\rm{s}}\)) to the total column/coil volume (\(V_{\rm{c}}\)), \(S_{\rm{f}} = V_{\rm{s}}/V_{\rm{c}}\).
2) It is recommended that phase ratio in counter-current chromatography be given the subscript V (i.e. \(\beta_{\rm{V}} = V_{\rm{M}}/V_{\rm{S}}\)) to emphasize phase volume ratio.
3) The \(\beta\) in counter-current chromatography has been defined as the ratio of planetary radius (\(r\)) over main rotor radius (\(R\)), \(\beta = r/R\).

Related Term
- counter-current chromatography: https://goldbook.iupac.org//terms/view/09887

Source
- PAC, 2017, 90, 181. 'Terminology of separation methods (IUPAC Recommendations 2017)' on page 204 (https://doi.org/10.1515/pac-2017-0111)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/16257/html
- json: https://goldbook.iupac.org/terms/view/16257/json
- xml: https://goldbook.iupac.org/terms/view/16257/xml

Citation: Citation: 'phase volume ratio' 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.16257
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Accessed: 2026-04-18T19:34:34+00:00