EXTRACTION OF CHROMIUM COMPLEX WITH ALIZARIN RED-S BY ALIQUAT-336 IN CHLOROFORM

Reaction of chromium with Alizarin Red S at various temperatures (from 22-degrees-C to 84-degrees-C) was investigated spectrophotometrically in pH range between 3.0 and and 6.7. Only chromium(III) forms in aqueous solutions with ARS coloured complexes of type 1:1 and 1:2 whereas bichromate ions are first reduced by the reagent to chromium(III). Only the complex anion Me(HL)2- is extracted into Aliquat 336 in chloroform. Absorption maximum for the complex in organic phase was found at 535 nm (epsilon = 2.21 x 10(4)). Beer's law is obeyed in the concentration range of chromium between 0.1 ad 2.5 ppm.