Biofuel cell retrieves copper

Jun 10, 2010 by Albert Sikkema

(PhysOrg.com) -- Producing energy and recovering copper from waste water at the same time: this is what Wageningen University environmental technologists are doing with their new microbial fuel cell.

'We obtain quite a lot of from the process. In addition, copper dissolved in water is turned into a layer of copper on the of the microbial fuel cell', says Annemiek ter Heijne, who published the basic principles of the in Environmental Science & Technology in the beginning of June.

In microbial fuel cells bacteria grow on anodes. They break down the organic waste in water and produce electrons. These electrons transmute the copper solution in the water into solid copper on the cathode of the fuel cell. Here an orange layer emerges which consists of pure copper. To make this process possible a special type of membrane is needed that regulates the pH value in the fuel cell.

Ter Heijne has now described the principles underlying this microbial fuel cell. Further research is needed to scale up and apply the process. She is thinking of applying the process in Chile, for example, to purify from the copper mines and simultaneously convert biomass into .

An elegant feature of the microbial fuel cell is that it enables environmental technologists to vary the extraction of copper and energy. Under oxygen-free (anaerobic) conditions 85 percent of the electrons produced by bacteria reclaim copper in solid form; under oxygen-rich (aerobic) conditions this is only 43 percent. In the latter case the fuel cell produces more energy.

'If your particular aim is to remove copper, it's better to work under oxygen-free conditions. But if you want to produce electricity, you have to add more oxygen', says Ter Heijne. The energy output of her prototype is high. Her guess is that acts as a catalyst in the production of energy.

Explore further: Cool alternative to electric kettle avoids excess water

Related Stories

Study: cow-powered fuel cells grow smaller, mightier

Aug 21, 2007

Cows could one day help to meet the rise in demand for alternative energy sources, say Ohio State University researchers that used microbe-rich fluid from a cow to generate electricity in a small fuel cell.

Progress Toward a Biological Fuel Cell?

Dec 30, 2008

(PhysOrg.com) -- Biological fuel cells use enzymes or whole microorganisms as biocatalysts for the direct conversion of chemical energy to electrical energy. One type of microbial fuel cell uses anodes (positive electrodes) ...

Recommended for you

Architects to hatch Ecocapsule as low-energy house

May 23, 2015

Where people call home depends on varied factors, from poverty level to personal philosophy to vanity to community pressure. Ecocapsule appears to be the result of special factors, a team of architects applying ...

Power to the batteries

May 22, 2015

Better solar panels and wind turbines are important to helping ensure a low-carbon future. But they are not enough. The energy from these intermittent sources must be stored, managed, converted and accessed ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.