Extraction of valuable metals from low-grade nickeliferous laterite ore by reduction roasting-ammonia leaching method
来源期刊：中南大学学报(英文版)2010年第4期
论文作者：陈胜利 郭学益 石文堂 李栋
文章页码：765 - 769
Key words：low-grade nickeliferous laterite ore; nickel; cobalt; reduction roasting; ammonia leaching; extraction
Abstract: Nickel and cobalt were extracted from low-grade nickeliferous laterite ore using a reduction roasting-ammonia leaching method. The reduction roasting-ammonia leaching experimental tests were chiefly introduced, by which fine coal was used as a reductant. The results show that the optimum process conditions are confirmed as follows: in reduction roasting process, the mass fraction of reductant in the ore is 10%, roasting time is 120 min, roasting temperature is 1 023-1 073 K; in ammonia leaching process, the liquid-to-solid ratio is 4:1(mL/g), leaching temperature is 313 K, leaching time is 120 min, and concentration ratio of NH3 to CO2 is 90 g/L:60 g/L. Under the optimum conditions, leaching efficiencies of nickel and cobalt are 86.25% and 60.84%, respectively. Therefore, nickel and cobalt can be effectively reclaimed, and the leaching agent can be also recycled at room temperature and normal pressure.
