LIBERATION AND CHARACTERISATION OF SOME NIGERIAN MANGANESE ORES

Abstract

ABSTRACT Nigeria is blessed with variety of solid mineral ores; manganese taking a good percentage. Nevertheless, no economic advantage has been derived because of

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inadequate metallurgical processing. This work investigated the chemical, mineralogical characterization and measured the liberation of manganese ores from Ka’oje in Kebbi State, Madaka in Niger State, and Akampa in Cross River State, Nigeria. Three ore sample of manganese weighing 9.8kg, 46kg and 27.2kg was collected commuted and screened to varying sizes. The sample for the SEM were carbon coated and focus in the machine generating images at different magnification. The Scan Electron Microscope (SEM) was used to assess the morphology of the ores while the X-ray fluorescence (XRF) Spectrometer identified the compositions of the ore, X-ray diffraction (XRD) Spectrometer assessed the mineralogical phases present in the ore. The SEM in conjunction with the XRD disclosed the ores to be chiefly Spessartite with Ilmenite, Quartz, Albite and Chlorite as the major mineral in sample A and B, while Quartz, Ilmenite, Magnetite and Garnet in sample C. the XRF disclosed that the major elements present are Al, Si, Mn, Fe (mean value of 26.75%, 40.89%, 24.72%, 4.07% respectively), Al, Si, Mn, Ca, Fe ( mean value 23.86%, 33.01%, 34.37%, 3.83%, 3.39% respectively), Al, Si, Fe ( mean value of 31.2%, 41.6%, 15.6%, 8.67% respectively) for Sample A, B and C respectively. The particle size analysis showed liberation being attained for particle size below 75µm across the three samples. The work index was calculated to be 4. 3 kwh/ton, 2. 4 kwh/ton, and 2. 0 kwh/ton respectively. The data garnered from the characterization indicated the three samples to be low grade manganese ores and would enable identification of effective treatment method for better exploration of the ore deposits.