Kinetics of the chelated copper cementation on aluminum particles in a rotary drum reactor

Copper recovery from EDTA containing solutions by cementation on aluminum particles was studied in a laboratory scale rotary drum reactor. The kinetics was investigated as a function of variables such as hydrogen ion concentration (pH), aluminum charge, and EDTA concentration. The kinetic model agrees very well with the experimental data and the induction time is due to the time needed for the growth of steady state copper deposit. The specific rate constant decreases with the increase of pH independent of the presence of EDTA. The specific rate constant is proportional to aluminum charge. The presence of EDTA has dramatic influence on the reduction of cementation rate, It is found that cementation rate decreases with the increasing concentration of EDTA. The structure of deposit and then the pore diffusion should have a pronounced effect on the diffusion of copper species and the dissolution of aluminum.