Silica gel modified with Eriochrome Blue SE as a sorbent in trace analysis for metal ions

The sorption of 14 metal ions on silica gel impregnated with a mixture of Aliquat 336 and Eriochrome Blue SE was investigated. It was found that the sorption behaviour depends upon the species and the pH of the loading solution. Alkali metal ions were not retained under any of the investigated conditions. The retained metal ions can be eluted with dilute solutions of hydrochloric or perchloric acid without significant elution of the chelating reagent from the sorbent. The sorbent was used for the separation of metal ion mixtures by column — extraction chromatography and for additional purification of some salt solutions from trace amounts of Zn, Cd, Pb and Cu. The effectiveness of purification was confirmed by anodic stripping voltammetry.