Preparation of ammonium jarosite from clinker digestion solution of nickel oxide ore roasted using (NH4)2SO4

To obtain the appropriate conditions for eliminating Fe3+ from NiSO4 solution, the digestion solution of the clinker was used as raw material, which was obtained from roasting the nickel oxide ore with (NH4)2SO4. The ammonium jarosite was successfully synthesized from the solution with analytic grade NH4HCO3. The effects of reaction temperature, reaction time, end pH value of reaction on the removal rate of iron were investigated, and the effect of the initial concentration of Fe3+ was also discussed. All of those factors had significant effects on the removal rate of Fe3+, among which the reaction temperature was the most prominent. The appropriate reaction conditions were concluded as follows: reaction temperature 95 °C, reaction time 3.5 h, end pH value of reaction 2.5 at initial concentration of Fe3+ 19.36 g/L. The physical aspect of (NH4)2Fe6(SO4)4(OH)12 was cluster figure composed of sheet or prismatic particles with smooth surface.