Effect of Binary Basicity (CaO/SiO2) on Selective Reduction of Lateritic Nickel Ore

A selective reduction method is being developed in processing lateritic nickel ore to produce high nickel grade's ferronickel using low temperature or energy consumption. This research was carried out to study the effect of binary basicity (CaO/SiO2) in the selective reduction process. The lateritic nickel ore containing 1.38% Ni and 38.2% Fe was used in this study. The reduction was performed at 1150 degrees C for 60 minutes in a muffle furnace with the addition of sodium sulfate (additives), bituminous coal (reductant), and calcium oxide (basicity modifier). The optimum nickel grade in the selective reduction of lateritic nickel ore was obtained from the 0.1 of binary basicity, which was 6.14 %Ni, due to the breakage of iron and nickel in magnesium silicate bond into metallic iron and nickel. Further increasing of binary basicity decreased the nickel grade of ferronickel due to the formation of a high melting point phase.