Preparation of Amberlite XAD resins coated with dithiosemicarbazone compounds and preconcentration of some metal ions.

The Amberlite XAD resins coated with dithiosemicarbazones were prepared and their collection behavior of metal ions from aqueous solution was investigated. Among the resins used, the reagent-loaded Amberlite XAD-7 was found to be superior for the collection of metal ions to other reagent-loaded resins used. The quantitative collection of mercury(II), palladium(II) and copper(II) was obtained from acidic medium, while cadmium(II) and lead(II) was obtained from neutral medium by the Amberlite XAD-7 resin coated with dimethylglyoxal bis(4-phenyl-3-thiosemicarbazone) (DMBS). These metal ions collected on the resin were easily eluted with a small volume of N,N-dimethylformamide as their DMBS chelates. This collection-elution method was applied to the determination of their metal ions by reversed-phase high performance liquid chromatography with a spectrophotometric detection.