Hydrometallurgical processing of nontronite type lateritic nickel ores by MHP process

Abstract

The research work presented in this paper determined the optimum conditions at which nickel and cobalt could be obtained at maximum efficiency from the column leach liquor of the lateritic nickel ore existing in Gördes region of Manisa in Turkey by performing effective hydrometallurgical methods. This column leach solution was initially neutralized and purified from its basic impurities by a two-stage iron removal process, nickel and cobalt were precipitated in the form of mixed hydroxide precipitate from the purified leach solution by a two-stage precipitation method called “MHP” and a manganese removal process was performed at the optimum conditions determined experimentally. By decreasing manganese concentration with this process to an acceptable level yielding at most 10% Mn in hydroxide precipitate, it was possible to produce a qualified MHP product suitable to the current marketing and standard conditions. The experiments conducted showed that by maintaining recycle leaching with sulfuric acid at which 95% of Ni–Co could be recovered from the precipitates, about 81% of Ni and 63% of Co in the lateritic nickel ore (9.72kg Ni/ton of ore and 0.28kg Co/ton of ore) could be extracted as mixed hydroxide precipitate by MHP process.