The Effect of Kinetics Parameters on Gold Extraction by Lewis Cell: Comparison between Synthetic and Leach Solution

Modern hydrometallurgical techniques have been adopted to produce high-purity gold. Many extractants were used for the extraction of gold from various synthetic solutions from which DiButyl Carbitol (DBC) had a unique superiority. Kinetics of process was studied in this paper and the influence of several parameters such as stirring speed, agitation time, impeller type, interfacial area, [AuCl4] - and DBC concentrations, pH and temperature on gold extraction were investigated. The increase in the stirring speed up to 300 rpm increased the extraction rate that means the process is diffusion control. Agitation time and interfacial area had a direct effect on gold extraction. It was found that using 4-blade impeller was better than 2-blade impeller.DBC and gold concentrations had positive effect on the extraction but pH had a negative. Enthalpy was obtained 14.27 kJ mol−1 indicating that the extraction of gold (III) in the investigated system was endothermic process. Similar study was carried out for leach solution obtained from aqua regia leaching of copper anode slimes. The results were compared, a correlation for gold extraction percent was then released using software.