EXTRACTION OF ALUMINUM AND SOME OTHER METAL-COMPLEXES WITH ALIZARIN RED-S INTO ALIQUOT 336 IN CHLOROFORM

Extraction of 15 metal complexes [Al, Ga, In, Cu, Ti(IV), La, V(IV), V(V), Mo(VI), Fe(III), Cr(III), U(VI), Th, Bi and Bel with Alizarin Red S (at constant reagent concentration = 6.3 x 10(-4) mol l-1) into 2 x 10(-3) mol l-1 Aliquat 336 in chloroform was investigated in pH range between 3.0 and 6.8. It was found that alkali metals and alkaline earth metals, zinc, cadmium, iron(II), cobalt, nickel and tungsten(VI) cannot form extractable complexes in these conditions. A strong increase of molar absorptivities after extraction was found for metals: Al, Ga, In, Fe(III), Be, Cu, V(V) and Mo(VI). It was found that aluminium is transferred into organic phase in the form of the complex of type AlL2. The presence of chloride and especially of nitrate and perchlorate ions in higher concentrations distinctly decreases the absorbance of aluminium complex in the organic extracts.