Pk. Sharma et Kh. Rao, Role of a heterotrophic Paenibacillus polymyxa bacteria in the bioflotation of some sulfide minerals, MIN MET PR, 16(4), 1999, pp. 35-41
A pure strain of Paenibacillus polymyxa and mineral-adapted strains are use
d to bring about surface chemical changes oil pyrite and chalcopyrite and,
thus, their flotation. Paenibacillus polymyxa was adapted by repeated subcu
lturing in the presence of pyrite and chalcopyrite. The surface chemical ch
anges of bacteria doe to adaptation and of minerals after their interaction
with bacterial cultures are evaluated by electrokinetic and infrared spect
roscopy and are discussed with reference to their flotation responses. Inte
raction of bacterial cells, bacterial metabolites and whole bacterial cultu
res affected the Hallimond flotation behavior of the sulfide minerals. The
Xanthate flotation results show that pyrite, but not chalcopyrite, is depre
ssed when the rests are carried out after interaction with chalcopyrite-ada
pted Paenibacillus polymyxa. This investigation demonstrated that the surfa
ce chemical properties of bacteria can be manipulated successfully to achie
ve the desired effects in the flotation process.