Supplements to preparative batch devices

An example made by connecting the outlet of a bV detector to a Waters Assoc, pump with small-diameter tubing is shown in Fig. 8. Fig. 8A shows the starting chromatogram and the separation shown in Fig. 8B was obtained by using eight cycles at 9 mVmin and a Z5 cm x 8 mm I. D. column. The silica used was Merckosorb Si 100, 5 um in diameter. Because of the good separation, it was possible to collect the two compounds without any loss of material. 

When evaluating a preparative chromatograph for gram-scale separations, we 

The stationary phase is allowed to flow down the column, while the sample and mobile phase enter continuously. Components with a relatively low solubility in the flowing liquid phase pass up the column counter-current to the sorbent flow and out at A. Components with higher solubility are retained in the moving bed and are stripped from the absorbent, as it passes B, by the mobile phase. 

Most of the development work on preparative liquid chromatography has been restricted to batch chromatography and batch systems and only comparatively recently has it been extended to continuous chromatography. For separations at pressures up to 30 bar a counter-current machine is commercially available. A schematic diagram of such a chromatograph, the so-called sequential separator 

Regarding the type of instrumentation that will have more widespread use in 

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