Hydrolysis polymers of metal ions

Inorganic polymers, such as metal hydroxo-polymers, sometimes exhibit strong adsorption onto gel materials or decomposition during elution. Thin-layer chromatography is a powerful method in such a case, because a whole chromatographic zone of a sample compound can be readily visualized and the comparison of various compounds is permitted on the same plate under identical conditions. 

Sinibaldi [ref. 99] has investigated the hydrolysis polymerization of six metal ions, i.e., iron(III), zirconium(IV), aluminium(III), lanthanum(III), thorium(lV) and titanium(IV), by thin-layer method with dextran and polyacrylamide gels. An acetate buffer (0.5 M) was used as eluent, because the solution was found to eliminate the adsorption or precipitation of hydrolyzed sample solutions which were prepared by adding various amounts of NaHC03 to the solution of a metal ion. The hydrolyzed solution of iron(III) yielded two spots on highly crosslinked gels (Bio-Gel P-2 and Sephadex G-25), of which the faster moved with the speed of the completely excluded marker Blue Dextran, and also 

Hydrolyzed chromium(III) also yields several zones when eluted on Sephadex LH-20 [ref. 105] or G gels [ref. 105, 106-109]. Osaki et al. [ref. 106] investigated the exclusion chromatography of trace amounts of chromate ions and hydrolyzed chromium(III) on Sephadex G-50, and concluded that all the chromium in the hydrolyzed solutions can be divided into four fractions the eluted fraction of lower molecular weight (fraction A), the eluted fraction of higher molecular weight (fraction B), the fraction adsorbed on the gel (fraction C) and 

C and 0 correlated with neither the pH of the sample solutions nor the storage times. It was also reported that the exclusion chromatography of hydrolyzed chromium(III) depends on the type of the anion in the eluent [ref. 107-109]. 

The interactions between zirconyl polymer and Cr(H20)e, Cr0 or IO3 in aqueous solution have been studied on thin-layer Sephadex G-10 plates [ref. 

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