Education and Technology

* Principles and Practice of Chromatography

Chromatography, although primarily a separation technique, is mostly employed in chemical analysis. Nevertheless, to a limited extent, it is also used for preparative purposes, particularly for the isolation of relatively small amounts of materials that have comparatively high intrinsic value. Chromatography is probably the most powerful and versatile technique available to the modern analyst. In a single step process it can separate a mixture into its individual components and simultaneously provide an quantitative estimate of each constituent. Samples may be gaseous, liquid or solid in nature and can range in complexity from a simple blend of two entantiomers to a multi component mixture containing widely differing chemical species. Furthermore, the analysis can be carried out, at one extreme, on a very costly and complex instrument, and at the other, on a simple, inexpensive thin layer plate.

*Preparative Chromatography

The loading of preparative columns is considered both practically and theoretically including the maximum column loading capacity, the maximum sample volume, volume overload, and mass overload. Preparative chromatography apparatus is then described including, solvent reservoirs, pumps, sample valves and the preparative columns themselves. The special requirements of preparative column detectors are also discussed together with the use of fraction collectors. The special packing techniques necessary for both preparative gas chromatography and liquid chromatography columns are described including both the radial and axial compression techniques. Procedures such as recycling, together with the moving bed and simulated moving bed systems are discussed in detail and some examples of the use of the moving bed system included.

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