Abstract
The box-Behnken design was used to layout the runs and conditions used to recover copper during leaching from chalcopyrite which was subjected to different roasting temperatures. The lixiviants sulphuric acid and the imidazolium ionic liquid 1-Butyl-3-methyl Imidazolium Hydrogen Sulphate [Bmim]HSO4 and sodium bromide were used and recoveries compared.
The methodology followed included leaching in a beaker with a solid liquid ratio of 10% with the two lixiviants, one being the sulphuric acid and the other the imidazolium based ionic liquid with the different parameters which were roasting temperature, leaching temperature, concentration and time.
With the addition of the bromide oxidant the imidazolium ionic liquid provided higher copper recoveries than the sulfuric acid alone. The ionic liquid has the advantage of being environmental friendly, while the sulfuric acid provides a simpler and cheaper option.