Transactions of the Society for Mining, Metallurgy, and Exploration, Inc.
Transactions home

  SME FaceBook SME Twitter SME LinkedIn RSS Feed

Improved nickel and cobalt recovery from nickeliferous laterites in acidic fluoride media

Minerals & Metallurgical Processing , 2010, Vol. 27, No. 3, pp. 117-123

Luo, Wei; Wang, Dianzuo; Qiming, Feng; Jiankang, Wentian


 Nickeliferous laterites were characterized by particle size analysis, X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive X-ray analysis (EDX), Fourier transform infrared (FTIR) spectroscopy and thermal analysis. Results showed that the laterites consist mainly of nickel-substituted lizardite with cobble-like morphology and traces amounts of magnetite and phlogopite. As fluoride ions can react with silicon in the lizardite crystal structure and form metal-fluoride complexes, as well as increase the equilibrium constant of the lizardite dissolution in acid solution dramatically, the addition of minor fluoride salts (0.2wt.% NaF) gave a markedly enhanced metal extraction rate (Ni 81.7% and Co 52.3%) under the experimental conditions of particle size d50= 25 μm, 10% (v/v) H2SO4, reaction time 2 h, reaction temperature 90°C, liquid-to-solid ratio 3 mL g-1 and stirring at 500 rpm compared with H2SO4 alone (Ni 69.6% and Co 30.8%).