Column bioleaching of a saline, calcareous copper sulfide ore

“Deep in situ biomining”, widely considered to be a potentially environmentally-benign and cost effective biotechnology for extracting and recovering base metals from deep-buried base metal deposits, is being developed within the EU Horizon 2020 project “BioMOre”. Data are presented from non-aerated column experiments in which a saline, calcareous copper-rich ore (Kupferschiefer) was subjected to a three-stage leaching protocol: (i) with water, to remove soluble salts; (ii) with sulfuric acid, to remove calcareous minerals and other acid-soluble salts; (iii) indirect bioleaching with a microbiologically-generated ferric iron lixiviant. Sequential leaching with water and acid removed ~85% of the chloride prior to bio-processing, while ~13% of the copper present in the ore was leached using sulfuric acid, and a further 39 - 59% by the lixiviant.