Biooxidación de concentrados de arsenopirita por Acidithiobacillus ferrooxidans en erlenmeyer agitados

arsenopyrite biooxidation process was evaluated with a. ferrooxidans atcc 23270. the microorganisms were previously adapted to mineral and two different tyler mesh sizes, 200 (~75μm) and 325 (~45μm). also, the mineral concentration was made by drx and molpp/lr under astm d 2799. the microorganisms were adapted through gradual decreasing of ferrous sulphate in successive state and subsequent arsenopyrite concentration increase. finally, biooxidation process was carried out without fe2+. after thirty days of process, arsenic bioleaching was 7550 mgl-1(18,7%) and 2850 mgl-1 (7,1%) for the 200 and 325 tyler meshes, respectively. on the other hand, bacterial growth curve showed, between 6 and 21 days of process that the average bacterial population was 1,70x108 cel.ml-1 y de 8,00x107 cel.ml-1 for 200 and 325 tyler mesh respectively. for this reason, the particle size played an important role in the adaption kinetics of microorganism. the results showed that the microorganism oxide the larger particle size of the mineral easier.