Collecting Cobalt and Developing a 'Green Energy Economy'
My name is Ed Thomas and I am a first year PhD student studying Geomicrobiology. This involves looking at how bacteria and microbes interact with rocks, minerals and metals in natural environments.
Geomicrobiology is relatively new scientific field but is rapidly growing; it has strong applications in answering many of Earth Sciences most pressing issues including: remediation of contaminated land, nuclear waste treatment and disposal, and reducing the environmental impact of mining and metallurgy industries.
My A-levels were in Geography, Chemistry and Maths, and I’ve always had a keen interest in all things Natural Sciences. I went on to do an integrated masters degree in Earth Sciences at the University of Manchester where my thesis was on the geochemistry of soft tissue fossils.
This is where I found my passion for studying the relationships between the biosphere and geosphere and I subsequently made the switch to studying Geomicrobiology. In September 2015 I started my PhD which looks at understanding the bioreduction process of Cobalt with a hope of ensuring a secure and sustainable supply of this crucial metal into the future.
Cobalt is one of only 4 elements classed as an ‘Energy Critical Element’ by the U.S. Department of Energy, the American Physical Society's Panel on Public Affairs and the Materials Research Society, and the European Union.
Due to its uses in the blades and magnets of wind turbines, in photovoltaic solar cells, and in rechargeable batteries for electric vehicles, ensuring a continuous and sustainable supply of cobalt is crucial to developing a ‘Green Energy Economy’ in the future.
What’s the problem?
Almost all of the cobalt mined in the world is as a secondary product, this means that we only find ores coexisting with other metals, usually copper or nickel.
In order to separate out and concentrate the different metals from the ore metallurgic processes often run at high pressure or very low pH. Then the metal compounds are reduced to obtain the pure metallic form.
These processes of acid leaching, froth floatation, and reduction often create hazardous and toxic products which are harmful to the environment and difficult to dispose of safely, as well as using lots of energy and electricity.
How is Geomicrobiology the solution?
Microbes and bacteria are constantly reducing and oxidising metals in the environment. Often these are very complex systems involving many species of bacteria and multiple metals and redox reactions.
If we can isolate individual species of bacteria that reduce certain metals in specific ways, then we can design reaction series to maximise the efficiency of the metal recovery process. By recreating and scaling up these naturally occurring reactions that have been perfected over millions of years of evolution, we will drastically be able to reduce the environmental impacts of the mining industry.
Additionally, there are certain unique reduction pathways that result in specialised end products such as nanoparticles which have a variety of uses. For instance, cobalt nanoparticles have potential uses in hydrogen fuel cells, medical sensors and imaging, cancer treatments, and high performance magnets.
Information about the CoG3 project can be found on our project partner, the Natural History Museum, website.
For information on cobalt nanoparticles and their potential applications there are many open access journal articles available including: http://www.hindawi.com/journals/jnt/2014/525193/cta/
And if you want to consider pursuing a career that will help us to understand and answer some of the biggest unsolved problems facing Earth, please consider studying Earth Sciences at university.