US EPA

4965322 

Journal Article 

A Sensitive Voltammetric Method for Chromium(VI) in Presence of Chromium(III) and its Application to Leather 

Kalender, DA; Yenigul, B; Ertas, FNil 

2011 

1 

Journal of the Society of Leather Technologists and Chemists
ISSN: 0144-0322 

95 

4 

152-157 

WOS:000294096900003 

The presence of chromium(VI) in leather is a subject of considerable interest in the tannery sector. Cr(VI) is usually controlled by standard spectrophotometric methods that utilize 1:5 diphenyl carbazide. However, the detection limit of this method is around the prohibited limit of Cr(VI) set for most of the leather products, being 3mgkg(-1). Present study describes the Catalytic Cathodic Adsorptive Stripping Voltammetric method for Cr(VI) determination in the presence of Cr(III). The Cr(VI) content of leather samples was extracted according to the IUC 18 standard method and it was reduced to Cr(III) in the presence of diethylenetriaminepentaacetic acid (DTPA) on a hanging mercury drop electrode (HMDE) at -0.90V. The catalytic effect of nitrate ions on the reduction peak of DTPA-Cr(III) complex was exploited for Cr(VI) analysis at sub-ppb level. Ion exchange resins were used to eliminate the interference of Cr(III) ions and their efficiency for removal was examined by ICP-OES. The voltammetric method was proved to be sensitive for Cr(VI) determination in leather samples in the presence of Cr(III).