Ce(III), Th(IV) and U(VI) chelates of alizarin viridine, alizarin heliotrope and alizarin maroon

The complexes of 7,8-dihydroxy-1,4-di(2′-sulpho-4′-methylanilano)anthraquinone (alizarin viridine); 1,4-dihydroxy-2(2′-sulpho-4′-methylanilino)anthraquinone (alizarin heliotrope) and 3-amino-1,2-dihydroxyanthraquinone (alizarin maroon) with Ce(III), Th(IV) and U(VI) have been investigated using spectrophotometric and conductometric methods. The study revealed the formation of complexes having the metal: ligand ratios 1:1 and 1:2. The values of log β* for the different complexes are determined. The structure of the ligands in the solid chelates were studied by i.r. spectrophotometry which showed that chelate formation takes place through the CO and neighbouring OH group and leads to proton displacement.