Studies on chromium(III) hydroxide, arsenate, antimonate, molybdate and tungstate.

Five water-insoluble compounds of chromium(III) have been synthesized by mixing 0.10M solutions of chromic chloride and the appropriate sodium salts in the volume ratio of 1:2, at pH 6-7. Their ion-exchange characteristics have been compared. The tungstate has the highest chemical stability and the arsenate has the highest ion-exchange capacity. Chromium(III) molybdate columns have been used to separate Pb(2+) from numerous metal ions.