Analisis Hubungan Kadar Hilang Pijar dengan Kandungan Unsur pada Bijih Nikel Laterit di Daerah Wolo, Provinsi Sulawesi Tenggara

The formation of laterite nickel deposits is controlled by several factors during the chemical weathering process, mainly by the chemical properties of the water that may be partially retained in the laterite nickel ore. Laterite deposits contain organic and inorganic materials which are cumulatively called loss on ignition (LOI) when it goes through the combustion process at high temperatures. The LOI content in lateritic nickel ore will affect the ore processing process so it needs to be analyzed. This study aims to analyze the relationship between LOI and the elemental content of lateritic nickel ore samples. The method used is X-Ray Diffraction analysis to determine the minerals in the sample, X-Ray Fluorescence analysis to determine the elements content in the samples, and LOI measurement using the high temperature combustion method in the furnace. The results of analysis exhibit limonite samples are dominated by goethite and gibbsite with minor quantity of magnetite and in saprolite samples are dominated by quartz and goethite. The LOI measurement reveal that the LOI value of limonite was higher than of saprolite. The results of the analysis on limonite samples, shows that LOI is positively correlated with Fe2O3, Na2O, and Al2O3 while LOI is negatively correlated with CaO, MgO, SiO2, MnO, Ni, Co, and Cr2O3. In the saprolite samples, the results of the analysis shows that LOI is positively correlated with Fe2O3, MnO, Ni, Cr2O3, Co and Al2O3 while LOI is negatively correlated with CaO, MgO, SiO2, and Na2O. The existence of this correlation can be identified the variations of elementals mobility at the weathering profile.