Sulfur enhancement effects for uranium bioleaching in column reactors from a refractory uranium ore

oleh: Qian Li, Qian Li, Yu Yang, Yu Yang, Jinfang Ma, Jinfang Ma, Jing Sun, Jing Sun, Guangyue Li, Guangyue Li, Ruiyong Zhang, Ruiyong Zhang, Zhao Cui, Zhao Cui, Ting Li, Ting Li, Xiaobei Liu, Xiaobei Liu

Format: Article
Diterbitkan: Frontiers Media S.A. 2023-01-01

Deskripsi

The feasibility of sulfur enhancement for uranium bioleaching in column reactors was assessed with a designed mixed Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans and Leptospirillum ferriphilum from a refractory uranium ore. The uranium extraction reached 86.2% with the sulfur enhancement (1 g/kg) in 77 days leaching process, increased by 12.6% vs. the control without sulfur addition. The kinetic analysis showed that uranium bioleaching with sulfur enhancement in columns followed an internal diffusion through the product layer-controlled model. Ore residue characteristics indicated that sulfur enhancement could strengthen the porosity of passivation layer, improving the ore permeability. Notably, bacterial community analysis showed that sulfur enhancement at 1 g/kg could make the iron-oxidizing and sulfur-oxidizing bacteria on the ore surface maintain a good balance (approx. 1:1), and thus decomposing ore more effectively. Lastly, a possible mechanism model for uranium bioleaching with sulfur enhancement was proposed.