Increased selectivity for planar chromatography by ion exchange: Cation chromatography on papers impregnated with titanium (IV) based inorganic ion exchanges in DMSO-HNO_3 mobile phases

摘要

Planar chromatography of thirty six metal ions on titanium (IV) phosphate, titanium(IV) tungstate and titanium (IV) molybdate impregnated papers in DMSO-HNO_3 mobile phases has been carried out. The ion-exchange of papers is determined and the effects of solvent composition, impregnation and pH on R_F values are studied. For K~+, Rb~+ and Cs~+, R_F = KC~1/2, where C is the nitric acid concentration. The movement of ions is explained on the basis of ion-exchange, adsorption and precitpitation. Alberti and Torracca's view for the prediction of elution sequence from R_F values has been checked. The sequence of adsorption of ions follows the order: titanium(IV) molybdate > titanium(IV) phosphate. Some of the anlaytically important separation are reported.