Sulfation-Roasting-Leaching of Brazilian Nickel Laterite Ore

Pedro Paulo Medeiros Ribeiro¹, Souza L. C. M.1, Santos I. D.², Radino-Rouse², and Dutra A. J. B.¹

1. Federal University of Rio de Janeiro, Brazil

2. Instituto Tecnológico Vale/Vale S.A, Brazil

Abstract: Exploitation of nickel from laterite ore resources has increased due to the depletion of high grade nickel sulfide ores. A hydro-pyrometallurgical route was applied in a sample of Brazilian laterite ore. The sample was pugged with sulfuric acid, subjected to a pre-roasting around 265°C, roasting around 690°C followed by water leaching. The operational parameters investigated were: leaching pH, acid amount; salt additions, particle size. Under favorable conditions nickel recoveries around 86% were achieved. These recoveries are strongly dependent on the particle size and sulfuric acid concentration due to the high amount of magnesia in the ore.

Key words: laterite ore, hydro-pyrometallurgical route, nickel