Cyanidation of tailings in artisanal small-scale gold mining at Arbaat Region in Red Sea State, Sudan

Year 2023, Volume: 62 Issue: 4, 191 - 196, 12.02.2024

Babiker Alkloos , Salih Aydoğan

https://doi.org/10.30797/madencilik.1416245

Abstract

In this research, the processing of gold from artisanal small-scale gold mining was investigated by cyanidation using an agitation process. The sample's characterization shows that the silicate mineral exhibits the sample mineralogy, according to the results of the XRD examination. In XRF analysis, the mineralogical and chemical structure shows 77.1% SiO2, 8.08% Al2O3, 5.76% Fe2O3, 1.67% CaO, 0.97% K2O, 0.054% As2O3, 1.1% Na2O, 0.392% SO3, 0.454% TiO2, 0.049% MnO and 0.005% ZrO. The parameters of the experiments were stirring speed, NaCN concentration, solid-liquid ratio, temperature, and pH. The purpose of gold leaching in artisanal small-scale gold mining at Arbaat region is to find the appropriate conditions that will ensure maximum recovery. It was found that the gold dissolution decreases with increasing solid ratio. Furthermore, the cyanide concentration positively influences the range of 0.05–0.5 g/L. It is seen that the dissolution rate increases with the range of pH 10-10.30, while it starts to incline at pH after 10.30. However, the temperature and agitation speed have a significant effect on the gold dissolution. Cyanidation tests revealed that it is easy to apply the cyanidation process and recover about 87.52% Au content from the tailings of artisanal small-scale gold mining. The obtained recovery indicates the commercial and economic viability of the process that will be applied to extract Au from artisanal small-scale gold mining tailings in Arbaat.

Keywords

Artisanal Small-Scale Gold Mining, Cyanidation, Agitation, Gold tailing

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