Author/Authors :
Karamoozian Mohammad نويسنده Assistant Professor, Mineral Processing, Shahrood University, 6KDKURRG Iran Karamoozian Mohammad , Azizi Asghar نويسنده Department of Mining, Petroleum and Geophysics, University of , Shahrood, 36199-95161, IranShahrood Azizi Asghar , Bayati Behrooz نويسنده Shahrood University of Technology
Abstract :
The leaching behavior of an Iranian copper oxide ore in sulphuric acid was
investigated in detail to evaluate the in
uence of various factors, to optimize the dissolution
conditions, and to determine the kinetics of the leaching. The results indicated that
the increase in the leaching time and temperature enhanced the leaching rate of copper.
The leaching rate increased up to a certain value with increasing the agitation rate, acid
concentration, and liquid/solid ratio and, then, reduced with a further increment. Agitaion
rate had the highest in
uence on the dissolution of copper. The 3D response surface
graphs con rmed the interactive e ects of sulphuric acid concentration, agitation speed, and
liquid/solid ratio with temperature. About 91% copper content was leached in 13% sulphuric
acid concentration, stirring rate of 600 rpm, liquid/solid ratio of 10 mL/g, and 50C
after 80 min leaching. The dissolution kinetics was examined according to heterogeneous
models. The shrinking core model, which considers the rate control by di usion through
the product layer, was found appropriate enough to describe the dissolution of copper in
sulphuric acid solution. The activation energy was obtained to be 26.699 kJ/mol, and
the equation representing the leaching kinetics of copper based on the di usion-controlled
model was found to be 1??3(1??x)2=3+2(1??x) = 161:97exp(??26:699103=8:314T)t.
