CHALCOPYRITE BIOLEACHING AND THERMOTOLERANCE OF 3 ACIDOPHILIC, FERROUS-OXIDIZING BACTERIAL ISOLATES

Three ferrous-oxidising, acidophilic bacterial isolates oxidised Fe2when growing on yeast extract; one isolate but not the other two grew on ferrous sulphate as the only energy source. The isolates did not gr ow on either pyrite, sulphur or thiosulphate, but they grew on chalcop yrite and solubilize copper. They are mesophiles but can be adapted to grow at 38 degrees C and 45 degrees C. Their bioleaching activities a t these temperatures were evaluated and compared.