Selective reduction of nickel from lateritic ore using Na2SO4 in an NH3 atmosphere

All sectors, including the ferronickel industry, are being encouraged by governments and campaigners to reduce CO 2 emissions due to their effect on the global climate. Compared to using reductants that contain carbon, free-carbon reductants are an alternative solution in decarbonizing the ferronickel industry, known as a CO 2 -intensive industry. This study uses NH 3 , one of the H 2 carriers, for the selective reduction process of nickel laterite ore, with Na 2 SO 4 serving as a selectivity additive. This study aims to investigate the selective reduction process of nickel laterite ore using Na 2 SO 4 in an NH 3 atmosphere. A Na 2 SO 4 variation of 0–20 % by mass was used to study this. For all Na 2 SO 4 addition variations, a fixed temperature and duration of 900 °C and 4 hours were used respectively. Based on X-ray diffractometer analysis, all variations of the Na 2 SO 4 mixture (0–20 %) can form metallic phases. The more Na 2 SO 4 is used, the reduction reaction extent increases and then decreases. Using a 900 °C, 4 hours, and 15 % Na 2 SO 4 additive mixture can achieve the highest reduction reaction extent of 81.6 ± 1.17 %. Morphologically, using 10 % Na 2 SO 4 or higher has been able to separate nickel- and iron-rich areas from impurities. Smelting experiments at 1600 °C also proved that ferronickel metal had formed. This early indication suggests that an NH 3 atmosphere can also facilitate the selective reduction of lateritic ores.