Preliminary Research of Synthesizing Battery Grade Nickel Sulphate from Dissolution of Nickel Matte in Dilute Sulphuric Acid

Abstract

Nickel matte is a smelter product of Indonesia mining, and it was produced from laterit ores by pyrometallurgy. The nickel matte composition is about 77% Ni, 1% Co and 0.3% Fe. This study is involving with synthesizing nickel sulphate by dissolution of nickel matte in sulphuric acid. The dissolution condition was varied by sulphuric acid grade, temperature and time of process. The dissolution process will be more effective in higher temperature and longer process time, with additional mangan oxide as catalyst. The efficiency process was observed from the filtrate, residue and nickel sulphate. The filtrate was evaluated by using Atomic Absorption Spectrometer, and residue/nickel sulphate were analysed by XRD. The more efficient process of nickel dissolution was observed at 95 °C for 3 hours, with the conversion rate about 55% - 60%. There was no difference result between sulphuric acid technical grade and pure analytic grade. After dissolution process, the synthesizing was using co-precipitation method in varied pH and alcohol/oxalic acid. The characterization of nickel suphate has been carried out by X-ray Diffraction. The most effective of synthesizing of nickel sulphate is adjusting the pH above 5. The product of nickel sulphate will be used a precursor material for lithium battery cathode materials.