RECOVERY EFFICIENCY STUDY ON ILESHA PLACER GOLD ORE BY FLOTATION USING LOCALLYSOURCED FROTHERS AND COLLECTORS

摘要

The research conducted by the defunct Nigerian Mining Corporation revealed that minablequantities of gold deposit are present over an expanse of Ilesha-Ife area. This optimism promptedseveral researchers to study the response of Ilesha gold ore to amalgamation and cyanidation.Unfortunately, these methods (amalgamation and cyanidation) are environmentally hazardous andthe reagents are rather expensive when available. This is the thrust for this research which is aimedat studying the amenability of Ilesha placer gold ore to froth flotation which is environmentallyfriendly using locally-sourced reagents. The mineralogical study of the deposit was carried out andthe result showed that the Ilesha placer deposit is non-refractory with fine-grained gold particles.Potassium salts of groundnut and palm kernel oils (as collectors) and their fatty acids (as frothers)were prepared and used to float gold concentrate from Ilesha placer gold ore. The following flotationparameters: pulp density, impeller speed, pulp pH, collector concentration and particle size analysiswere optimised. The results obtained shows that optimum recovery of 91.8 per cent and 89.56 percent of gold concentrates were obtained at pulp pH of 9, pulp density of 100 g/cm3, impeller velocityof 1350 rpm and mineral particle size range of -75 μm when potassium salts of groundnut andpalmkernel oils were used respectively as collectors. Thus Ilesha placer gold ore is amenable to frothflotation using locally-sourced frothers and collectors.