Influence of triton X-100 in a micellar solution and in an emulsion on the polarographic behaviour of cobalt and determination of cobalt in paint driers and varnishes by differential-pulse polarography

Abstract

The polarographic behaviour of Co(II) in an aqueous medium, in aqueous Triton X-100 and in a toluene-water emulsion was studied in ammonium thiocyanate-ammonia buffer. Both the Triton X-100 and the emulsion decrease the Co(II) peak height and shift the peak potential to more cathodic values. The polarographic process of Co(II) is controlled by diffusion in the three media mentioned above. The process is reversible in aqueous medium and the addition of Triton X-100 makes the process irreversible; the emulsion improves the reversibility of the polarographic process. Cobalt was determined in paint driers and varnishes by means of emulsion formation, using emulsified aqueous standards.