SOLVENT-EXTRACTION SEPARATION OF CU(II) AND NI(II) WITH BIS(2,4,4-TRIMETHYLPENTYL)DITHIOPHOSPHINIC ACID (CYANEX-301)

The extraction behaviour of copper(II) and nickel(II) with bis(2,4,4-t rimethyl pentyl)dithiophosphinic acid has been studied at various para meters such as, pH, acidity, reagent concentration, equilibration peri od, solvent effect and effect of diverse ions. The copper(II) was quan titatively extracted from 0.5 M HCl with 5 x 10(-3) M Cyanex 301 and n ickel(II) was extracted at pH 8.00 with 5 x 10(-3) M Cyanex 301. The b rownish yellow copper complex absorbed at 440 nm while coloured comple x of nickel showed maximum absorption at 340 nm. Both metals were sepa rated from multicomponent mixtures. The proposed method was successful ly employed for the determination of copper and nickel in real samples .