Electrogenerative leaching of nickel sulfide concentrate with ferric chloride

Abstract

In order to utilize the chemical energy in hydrometallurgical process of sulfide minerals reasonably and to simplify the purifying process, the electrogenerative process was applied and a dual cell system was introduced to investigate FeCl₃ leaching of nickel sulfide concentrate. Some factors influencing the electrogenerative leaching, such as electrode structure, temperature and solution concentration were studied. The results show that a certain quantity of electrical energy accompanied with the leached products can be acquired in the electrogenerative leaching process. The output current and power increase with the addition of acetylene black to the electrode. Varying the components of electrode just affects the polarization degree of anode. Increasing FeCl₃ concentration results in a sharp increase in the output of the leaching cell when c(FeCl₃) is less than 0.1 mol/L. The optimum value of NaCl concentration for electrogenerative leaching nickel sulfide concentrate with FeCl₃ is 3.0 mol/L. Temperature influences electrogenerative leaching by affecting anodic and cathodic polarization simultaneously. The apparent activation energy is determined to be 34. 63 kJ/mol in the range of 298 K to 322 K. The leaching rate of Ni²⁺ is 29.3% after FeCl₃ electrogenerative leaching of nickel sulfide concentrate for 620 min with a filter bag electrode.

Keywords

nickel sulfide concentrate / FeCl₃ / electrogenerative leaching