LEACHING OF LATERITIC NICKEL ORES OF KARACAM (ESKISEHIR-TURKEY) WITH HYDROCHLORIC ACID

In this study, nickel extraction from Karacam (Eskisehir) region laterites by hydrochloric acid leaching is aimed. The mineralogical analysis showed that the ore sample contains goethite, hematite, wustite, retgersite, gaspeite and clay type minerals together with quartz. The effects of various parameters such as leaching time, stirring speed, acid concentration and leaching temperature on nickel recovery were determined. The shrinking core model was applied to the results of experiments investigating the effects of leaching temperature range of 40-90 degrees C. Two equations were applied from obtained results from each temperature value. Their correlation coefficients for each temperature are calculated. These results indicate that the dissolution rate of Ni is controlled by diffusion. The activation energy (Ea) for the dissolution reaction was calculated as 74.52 kJ/mol. Arrhenius constant was calculated to be 8.9633 s(-1).