Extraction Technologies For Medicinal And Aromatic Plants - Unido

EXTRACTION TECHNOLOGIES FOR MEDICINAL AND AROMATIC PLANTS
CCC has its origin in the work of Archer John Porter Martin and
Richard Laurence Millington Synge (Martin and Synge, 1941; Synge, 1946)
carried out in Britain during World War II. For their pioneering work, Martin
and Synge shared the 1952 Nobel Prize in Chemistry. Soon after their work
appeared, Lyman Creighton Craig and Otto Post developed an apparatus
that essentially consisted of a series of separatory funnels (“tubes”) (Craig
and Post, 1949). The sample was “automatically” transferred through the
Craig-post apparatus (Figure 1). Over 1000 mixing and separation steps
could be accomplished in one day.
Figure 1: Craig-post apparatus
Individual components were separated based on their partitioning
behavior. Craig and Post continuously improved their apparatus and were
commercially quite successful. Over 1000 publications on “counter-current
distribution” appeared during the period 1950-1970 citing the use of the
Craig-post apparatus.
13.2.2 Partition Coeffi cient
For a given substance A, the partition coeffi cient KA is defi ned
the concentration of A in the upper phase divided by that in the lower phase
(Figure 2).
Figure 2: KA= [A] upper phase/[A] lower phase
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