Countercurrent distribution apparatus

Hhen the distribution constant is very - f small continuous liquid-liquid extraction or f countercurrent distribution apparatus is required. 

An additional method of increasing the efficiency of liquid-liquid extraction is based on the countercurrent distribution principle [80-861 Early countercurrent distribution apparatus... 

Find, in a reference book, a description of the Craig countercurrent distribution apparatus and discuss its design as it relates to the description of countercurrent extraction presented in this chapter. 

Fig. 15. ORSEP multi-stage countercurrent distribution apparatus...

The different method of operation makes the single withdrawal procedure suitable for the separation of samples with a different range of distribution ratios to those commonly separated by the fundamental procedure. Substances with high G values are easily eluted in the upper phase by this method while those with low G values need a greater number of transfers to be carried through the countercurrent distribution train. The opposite is true when the lower phase is withdrawn. The greater the number of transfers, the more diluted the sample components are when eluted from the countercurrent distribution apparatus. 

Figure 4 Thin-layer countercurrent distribution apparatus. The two Plexiglass disks contain matching cavities for the upper and lower phases and by rotation the upper plate can move all upper phases relative to the lower ones.

Craig countercurrent distribution The Craig countercurrent distribution apparatus was used to perform numerous distinct sequen-... 

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