Patent ID: 8187360
Filing Date: 2012-05-29
Classification: C22B,Y02P

Abstract:
1. A process for the instantaneous control of the precipitation of Ni and Co present in a leach liquor resulting from the pressure acid leaching of laterite ores using pH adjustments to the solution, comprising: a. precipitating Al, ferric Fe, and Cr while minimizing the precipitation of Ni, Co, and Mn by making additions of lime and/or limestone to the solution while controlling the pH in the solution within a first pre-determined range; b. precipitating ferrous Fe while minimizing the precipitation of Ni, Co, and Mn by making additions of lime and/or limestone to the solution while controlling the pH in the solution within a second pre-determined range; c. separating the precipitated Al, ferric and ferrous Fe, and Cr from the solution; and d. precipitating Ni and Co by making additions of magnesia to the solution while controlling the pH of the solution within a third predetermined range, wherein the procedure for precipitating Ni and Co from the solution comprises the steps of: