Extraction of valuable metals from low-grade nickeliferous laterite ore by reduction roasting-ammonia leaching method

• Published in: Journal of Central South University of Technology. Science & technology of mining and metallurgy Vol. 17; no. 4; pp. 765 - 769
• Main Authors: Chen, Sheng-li, Guo, Xue-yi, Shi, Wen-tang, Li, Dong
• Format: Journal Article
• Language: English
• Published: Heidelberg Central South University 01.08.2010
• Subjects: Engineering; Metallic Materials; nickel; cobalt; low-grade nickeliferous laterite ore; reduction roasting; extraction; ammonia leaching
• ISSN: 1005-9784; 1993-0666
• DOI: 10.1007/s11771-010-0554-9

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 NH 3 to CO 2 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.