SEPARATION OF METAL-CYANIDE COMPLEXES BY REVERSED-PHASE ION-INTERACTION HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY

Reversed-phase ion-interaction chromatography has been used to study the separation of Cu(I), Ag(I), Ni(II), Au(I), Co(III), Fe(III), and Fe(II) cyano complexes on silica and carbon-based reversed-phases with UV detection at 215 nm. Separation of the metal-cyanide complexes was affected by a number of experimental factors including the nature and concentration of the organic modifier, nature and concentration of the ion-pairing reagent, pH, and ionic strength of the mobile phase. Differences between the elution order of metallo-cyanides observed in the present work and in other investigations under similar experimental conditions are explained by a difference in the ionic strength of the mobile phase. Finally, this technique is used to analyze metal-cyanide complexes in a gold mill solution.