Aluminum supports, thin layer chromatography

Similar effects were observed by Stigter e< al. (185) with silica and aluminum chloride. The assumption of hydrolytic adsorption is supported by an observed increase of conductivity upon addition of silica to aluminum chloride solutions. Kautsky and Wesslau (240) observed hydrolytic adsorption of Th + ions. The reaction scheme given above is a simplification since, in reality, solutions of basic iron or aluminum salts contain polynuclear complexes. The size of the aggregates depends on pH and concentration. Chromatographic separation of various metal ions on silica gel columns was first described by Schwab and Jockers (241). The role of hydrolytic adsorption in column chromatography on silica gel was stressed by Umland and Kirchner (242). The use of this technique in analytical separations was investigated in detail by Kohlschiitter and collaborators (243-246). An application to thin-layer chromatography was described by Seiler (247). 

Thin-layer chromatography (TLC) is a planar form of chromatography useful for wide-scale qualitative analysis screening and can also be used for quantitative analysis. The stationary phase is a thin layer of finely divided adsorbent supported on a glass or aluminum plate, or plastic strip. Any of the solids used in column liquid chromatography can be used, provided a suitable binder can be found for good adherence to the plate. 

Thin-layer chromatography on cellulose or silica gel (supported on paper, glass, or aluminum) ... 

The development of LC was rapid with the appearance of several different methods and techniques. Some trends are outlined. Liquid-liquid chromatography (LLC) was introduced in 1941. In this case, both the stationary phase and mobile phase are immiscible liquids. The stationary phase is a porous material (support) covered with a thin film of liquid. A variation of LLC is paper chromatography (PC), where the stationary phase is paper with the water included in its pores. PC was the first planar technique. The term planar comes from the fact that the stationary phase (paper) is a two-dimensional bed. A subsequent planar technique is thin-layer chromatography (TLC). In this case, the stationary phase is a thin layer of solid material, composed of small particles, spread on a glass plate or an aluminum sheet. 

Thin-layer chromatography (TLC) stationary phase is a thin layer supported on glass, plastic, or aluminum plates. 

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