Thin-Layer Chromatography of Metal Ions in Formic Acid Medium on Impregnated and Unimpregnated Silica Gel G: Semiquantitative Determination of Fe³⁺, Cd²⁺, Th⁴⁺, Al³⁺, Zn²⁺, UO²⁺₂, VO²⁺, Ce⁴⁺, and Ni²⁺

Abstract

The adsorption behavior of metal ions in the formic acid-sodium formate system using unimpregnated as well as impregnated silica gel G as thin layers has been studied. A remarkable result of this study is the dramatic selectivity of impregnated silica gel G thin layers when compared to the corresponding unimpregnated silica gel G thin layers. This impregnation effect provides us with a new adsorbent phase which is sufficiently stable in the formic acid-sodium formate medium. Some important ternary separations have been achieved on silica gel G thin layers. Al³⁺, Ni²⁺, Fe³⁺, and Pb²⁺ have been qualitatively separated from mixtures of other ions. Cu²⁺ has been selectively separated on impregnated silica gel G thin layers. The semi-quantitative determination of nine metal ions on impregnated silica gel G layers has also been attempted.