Bioleaching of Low Grade Tellurium Sulfide Mineral

The leaching of tellurium from the low-grade sulfide mineral in shake flasks was investigated by using mixed bacteria enriched from the acid mine drainage in Shimian Tellurium Mine in China and Acidithiobacillus ferrooxidans (A.ferrooxidans) isolated from the mixed bacteria, named as W-18 and PD-2, respectively. The results showed that, with inoculation amount of 10%(volume fraction), temperature of 30i°C, initial pH of 1.5, shaking speed of 150 r/min, pulp granularity of <0.165 mm over 85% and pulp density of 2% (mass fraction), the tellurium extraction efficiency can amount to 76.3% by using W-18 after 30 days of leaching, while using PD-2 as inocula, the extraction efficiency can only reach 66.3% after 30 days of leaching with the same leaching parameters exception for initial pH of 2.0. It indicates there may be a bigger potential for bioleaching of the low-grade ore by using the mixed bacteria W-18 than the pure A. ferrooxidans strain PD-2.