Roast-neutralization-leach technique for the treatment of laterite ore

摘要

A method is provided for enhancing the neutralization capability of high-magnesium serpentine silicate ore in the neutralization of nickel-containing pregnant leach solution, said solution having a pH of less than about 1 which comprises, providing said high magnesium serpentine ore in particulate form containing by weight over about 5% magnesium, roasting said ore under oxidizing conditions at a temperature below that temperature at which forsterite in said ore recrystallizes, and then adding an amount of said serpentine roasted ore to said pregnant liquor sufficient to raise the pH of the leach solution to a level above 2.