Determination of gold(I) in cyanide solutions by solvent extraction and atomic absorption spectrometry

Solvent extraction in the presence of emulsion-forming residues. Application to the atomic absorption determination of gold in low-grade ores

“…Tests in which the 3 AY HC1 was used as the aqueous phase show that HC1 has less effect than HN03 on the solubility of MIBK. The absence of MIBK volume increase at low aqueous-to-MIBK ratio indicates little extraction of HC1 as previously reported (7).…”

Quantitative determination of gold in solution by solvent extraction and atomic absorption spectrometry

“…Additional experiments demonstrated that quantitative extraction was possible when the cyanide concentration was 10-3M, and the concentration of this extractant was increased to 1 % (w/v). Provided sufficient cyanide was present in the aqueous phase, the effect of the other parameters listed in Table I upon the solvent extraction of gold(III) were identical to the results described for the extraction of gold(I) into diisobutyl ketone (7). In both cases the trioctyl methyl ammonium salt could be loaded to near theoretical quantities of gold, indicating that each of the gold complex ions is probably solvated by one molecule of this quaternary ammonium salt.…”

“…Precision and Accuracy. The relative standard deviation when analyzing solutions of gold(III) was the same as during the determination of gold(I) cyanide solutions (7).…”

“…For the determination of gold(III) in aqueous solution it is recommended that the gold be extracted into a diisobutyl ketone phase containing 1 % (w/v) of trioctyl methyl ammonium chloride. Volume ratios between 1:1 and 100:1 may be selected to ensure that the concentration of the gold(III) in the diisobutyl ketone phase will give a suitable spectrometric response (7).…”

Determination of trace levels of gold(I) as its cyano complex by ion-interaction reversed-phase liquid chromatography with on-line sample preconcentration

“…Flame AAS is suited to the determination of gold at levels of approximately l ppm and higher, whereas graphite furnace AAS is applicable to much lower concentrations. When analyses in the low parts per billion range are required, it is generally necessary to preconcentrate the sample by solvent extraction, typically using a liquid ion-exchanger in MIBK as the extracting solvent (2, 3 ) . Other analytical techniques for gold such as inductively coupled plasma atomic emission spectrometry ( 4 ) , electroanalysis ( 5 ) , X-ray fluorescence (6), and neutron activation analysis (7) either have insufficient sensitivity for ultratrace applications or are very time-consuming.…”