PROCESS OF BIOLIXIVIACAO DE MINERIOS CONTAINING COPPER SULFURETES BY INDIRECT CONTACT WITH FERRIC SULPHATE SOLUTIONS AND 'THIOBACILLUS FERROOXIDANS' SUPPORTED, WITH SEPARATION OF EFFECTS.

摘要

Process for biolixiviating minerals from copper sulfides and also from their flotation concentrates, characterized by the use of biolixiviation through indirect contact as well as separation and improvement of the chemical and biological steps of the biolixiviation process. In the chemical step, a low concentration of ferric sulfate is used as the lixiviating agent. In the biological step, bacterial films of Thiobacillus ferrooxidans attached to an inert solid are used to regenerate the lixiviating agent by converting the ferrous ion into ferric ion through oxidation. The regenerated agent is then recycled to the lixiviation reactor. The biolixiviation process permits complete extraction of the copper contained in the ore and results in a lixiviation liquor which contains all the copper charge and a low concentration of ferric sulfate similar to the low concentration of ferric sulfate used initially. The copper obtained can be treated without difficulty by means of extraction with solvents and electrolysis in order to obtain cathode copper.