Ion exchange divalent-monovalent

The LUB approach is used for the adsorption step. During desorption a proportional pattern (diffuse) wave usually results as shown in Figure 18-15B (monovalent-divalent ion exchange can be an exception to this—see Exanple 18-8). Since the shape of the pattern changes with length, the LUB approach cannot be used for desorption. However, the results of the solute movement theory for diffuse waves are often quite accurate. Thus, the diffuse wave predictions can be used for preliminary design. The desorption step should be checked with experimental data. 

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