EFFECT OF ACID CONCENTRATION ON THE EXTRACTION OF NICKEL FROM LATERITE

Nickel is essential metal due to usage area as stainless steel, non-ferrous alloy production, electroplating and chemical industry. Degradation of nickel sulphides leads to extraction of nickel from laterites. High cost equipment of high pressure acid leaching and since heap leaching needs longtime, atmospheric acid leaching of laterites becomes popular. Parameters of atmospheric leaching are important in terms of acid consumption, content of pregnant solution and residue. Therefore in this study, lateritic nickel ore from ManisaCaldag/Turkey was leached for determining acid concentration parameter, both sulfuric acid and nitric acid sulfuric acid mixture with varying percentage by volume. XRD analysis of lateritic nickel ore was showed that the ore mainly consist of quartz and goethite. Pregnant leach solutions were analyzed with atomic absorption and leach residues were characterized by X-ray diffraction and scanning electron microscopy. Increment of acid concentration caused increased nickel content in the solution but iron content increased as well.