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

11th International Multidisciplinary Scientific GeoConference SGEM2011, www.sgem.org, SGEM2011 Conference Proceedings/ ISSN 1314-2704, June 20-25, 2011, Vol. 1, 1155-1162 pp

ABSTRACT

In this study, nickel extraction from Karaçam (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 °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.

Keywords: Laterite ore, Nickel, HCl, Karaçam (Eskişehir), Turkey.