ABSTRACT
In the present study the results of a comparison of the leaching of a refractory copper sulphide ore as well as its concentrate is discussed. Inoculated with bacteria and bacterial ferric liquor tests were performed in order to examine the importance of the bacterial ferric solutions as leaching agent. The investigations have concentrated upon the use of percolation leaching techniques. The leaching tests were conducted in order to define the major factors influencing the oxidation of copper sulphides and to underline the importance of indirect leaching of the copper sulphide minerals by bacterially generated ferric sulphate solutions. The parameters studied were the particle size of ore and the initial ferric ion concentration in solution. The rate of copper dissolution was found to be almost directly proportional to the surface area of the ore. In addition, the rate of copper release was insensitive to ferric iron concentration higher than lg/lFe+3 in the leach solution.
