London, Sep 7 (Inditop.com) Using bacteria and inositol phosphate, a chemical residue of cheap waste material from plants, researchers have recovered uranium from effluents discharged by uranium mines.
“By using a cheap feedstock easily obtained from plant wastes we have shown that an economic, scalable process for uranium recovery is possible,” says Lynne Macaskie, microbiology professor at Birmingham University (B-U), who led the research.
Bacteria, in this case E. coli, break down a source of inositol phosphate, a phosphate storage material in seeds, to free phosphate molecules.
The phosphate then binds to the uranium forming a uranium phosphate precipitate on the bacterial cells that can be harvested to recover the uranium.
This process was first described in 1995, but then a more expensive additive was used and that, combined with the then low price of uranium, made the process uneconomical.
The discovery that inositol phosphate was potentially six times more effective as well as being a cheap waste material means that the process becomes economically viable.
As an example, if pure inositol phosphate, bought from a commercial supplier is used, the cost of this process is $2.81 per gram of uranium recovered. If a cheaper source of inositol phosphate is used (e.g. calcium phytate) the cost reduces to $0.14 for each gram of recovered uranium.
The world price of uranium is likely to increase as countries move to expand their nuclear technologies in a bid to produce low-carbon energy.
Macaskie presented these findings at the Society for General Microbiology’s meeting at Heriot-Watt University, Edinburgh.
