Magnesium recycling and sulphur recovery in leaching of lateritic nickel ores

摘要

The present invention resides in a process of recovering nickel and cobalt, regenerating the main raw materials, said process including the steps of: granulometric separation; leaching; neutralization; MHP production in only one stage and the pressure crystallization of magnesium sulphite. The process proposes a way to recovery nickel and cobalt from laterite ores through the atmospheric and heap leaching with staged addition of ore - by size separation - and H2SO4, decreasing the nickel losses and simplifying the neutralization circuit and producing a more purified MHP. The present process route is employed for nickel extraction, including the one from high magnesium containing lateritic ores.