DETERMINATION OF ALUMINUM IN NATURAL-WATERS BY SINGLE-COLUMN ION CHROMATOGRAPHY WITH INDIRECT UV DETECTION

The selective, sensitive and rapid determination of Al was achieved using ion-exchange separation and indirect UV detection. A solution of Ce salt was used as the eluent. The parameters influencing the shape of the Al peak, the selectivity of Al separation and sensitivity of its determination were studied. The separation of Al on chemically modified and on silica gel-based dynamically coated sorbents was achieved. With direction injection the detection limit under the optimum conditions was 50 ng/ml. The time of analysis was about 6 min. The use of a simple preconcentration procedure permitted the detection limit to be decreased. Preconcentration of Al was performed on a complexing sorbent with iminodiacetate functional groups. The technique presented was applied to the determination of Al in natural and tap waters. The technique also provides the determination of alkaline earth metals along with Al.