Electrochemical trace analysis of gold in ore

Abstract

Differential-pulse polarography (DPP) has been successfully used for the simultaneous determination of some trace metal ions in ore. Ammonium tartrate (0.1 mol l^–1) was used as supporting electrolyte and 0.01% gelatin as maximum suppressor. The sample produced eight well defined polarographic peaks. The first signal with E_p=–0.08 V versus SCE in the polarogram may be due to Ag^I or Au^III. To confirm the presence of Ag^I and/or Au^III in the sample, EDTA was used as a complexing agent, which resulted in this single peak splitting into two, with E_p equal to –0.04 V and –0.2 V versus SCE, confirming the presence of both Ag^I and Au^III in the sample. The observed voltammetric results were compared with those obtained by using AAS.