Title: Craig countercurrent distribution apparatus
Long Title: IUPAC Gold Book - Craig countercurrent distribution apparatus
DOI: 10.1351/goldbook.10210
Status: current

Definition
Apparatus for extraction based on a multistage countercurrent distribution.

Note
The Craig CCD apparatus consists of a battery of glass vessels designed to allow the mixing, settling, and transfer of extracted phase (sample) and the addition of fresh solvent (extractant) in a repetitive fashion. Movement about the horizontal axis provides gentle mixing of the phases, settling, and decanting of the upper phase. The extraction process is slow but is fully automated.

Related Term
- multistage countercurrent distribution: https://goldbook.iupac.org//terms/view/10217

Source
- PAC, 2016, 88, 517. 'Glossary of terms used in extraction (IUPAC Recommendations 2016)' on page 534 (https://doi.org/10.1515/pac-2015-0903)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/10210/html
- json: https://goldbook.iupac.org/terms/view/10210/json
- xml: https://goldbook.iupac.org/terms/view/10210/xml

Citation: Citation: 'Craig countercurrent distribution apparatus' 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.10210
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Accessed: 2026-08-05T21:20:36+00:00