SEPARATION AND DETERMINATION OF PLATINUM METALS AND SOME TRANSITION-METALS BY REVERSED-PHASE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY

A new reagent, 6-methyl-2-benzothiazolylazo)-5-diethylaminophenol (MBT AE), which was synthesized for the first time by us, was used as a pre column derivatizing reagent in the determination of platinum metals an d some transition metals by reversed-phase HPLC. The effects of the co mposition and general properties of the mobile phase, column temperatu re and foreign ions on the retention behavior of the metal-MBTAE compl exes are discussed in detail. The platinum metals and some transition metals can be separated on a Spherisorb C-8 column at a detection wave length of 575 nm using a 73/27(v/v) methanol/water containing 20 mmol/ l pH 6.0 acetate buffer and 12 mmol/l malic acid as the mobile phase. The detection limit of each metal ion is as follows (ng): Ru 1.77, Rh 0.057, Pd 0.17, Os 0.89, Ir 0.47, Pt 0.55, Co0.18 and Ni0.06, respecti vely, when the signal-to-noise ratio is 2. This method has been used t o analyze mineral and anode slime samples. The results correspond to t he certified values, and quantitative metal recoveries were obtained.