Microbial Extraction of Antimony from Stibnite of Qillah Abdullah

The study involve bioleaching of antimony ore collected from Qillah Abdullah   Balochistan (Pakistan) by using Thiobacillus ferrooxidans isolated from coal mine drainage of district Harnai. Analysis of ore revealed that it has 19.54% antimony along with 42.24% SiO 2  as gangue material. Trails for bioleaching were conducted in shake flasks having 10% (w/v) ore and growth medium. Isolated microorganisms were found more efficient for liquification of antimony contents at grain size -150#. Liquefied antimony was recovered as antimony sulphide by  precipitation  with H 2 S. Parameters affecting the process of bioleaching such as aeration, time period, temperature, grain size of ore and pH were also optimized. Overall recovery of product was estimated as 73% in 120 days.