Nuclear Research Laboratory, Indian Agricultural Research Institute, New Delhi, 110012
Comparison of the desorption of the ion pair, Mg-H from montmorillonite by equilibrium batch exchange and continuous exchange, using KCl as the replacing agent showed that the release of Mg by the latter procedure was lower as compared with that by the former, whereas the release of H followed the opposite trend.
Calculation of $$fMge/fHe showed that this ratio decreased with progressive desorption of Mg and H. It was also seen that $$fMge/fHe increased with increasing and decreasing concentrations of Mg and H, respectively in the system. Higher concentrations of KCl (starting from 0.2S to 20S) were found to enhance the desorption of Mg but not to affect that of H to any significant extent. A concentration of 6S KCl was required to completely replace exchangeable Mg from (20Mg-80H)-montmorillonite system, whereas as high as 20S of KCl replaced 98 and 92% of exchangeable Mg from 50Mg-50H and 80Mg-20H montmorillonite systems, respectively. Consideration of utilization of added K in replacing (Mg+H) and Mg alone showed that with higher concentration of KCl, the replacing efficiency of K as expressed by percentage of K utilization value, decreased.
Continuous ion exchange, ion exchange in montmorillonite, batch ion exchange
