Principles and Practice of Chromatography - Chromatography Applications > Liquid Chromatography Applications > Ionic Interaction Chromatography > Page 86


An example of the use of ion interactions to separate the non-selective contact herbicides Diquat and Paraquat is given in figure 46. The column was fairly large (10 cm long and 7.6 mm in diameter) and was packed with cross-linked polystyrene beads, 9 mm in diameter, carrying -COOH groups as the interacting ion moieties. At the optimum flow rate the column would give about 5,500 theoretical plates but at the flow-rate used which was 1 ml/min. the efficiency would be considerably below that. Nevertheless, it is clear that a very good separation was obtained.


Courtesy of Asahi Chemical Industry Co. Ltd.


Figure 46 The Separation of the Herbicides Diquat and Paraquat