Fungi Help with Recycling

It is the age of the technology. Everyone has a laptop or a smartphone and, at the root of all of this new technology is energy. The rechargeable batteries in our electronic devices require the use of two minerals that are growing scarce in supply, leaving suppliers struggling to keep up with the growing demand for rechargeable batteries. According to statista, the demand for lithium alone is projected to surpass 400,000 metric tons by 2025, doubling our current demand.

For some people, the answer is simple, dig up more of the minerals like lithium and cobalt that are in such high demand. Current metal extraction processes require high heat and chemicals. These methods are not environmentally friendly but the alternative is to dig up more of the Earth’s crust.

In order to address this problem, researchers from Florida are planning on presenting a possibility at the 252nd National Meeting & Exposition of the American Chemical Society. Led by Jeffrey A. Cunningham, the team will be proposing the use of fungi to separate the metals from batteries.

The researchers have tested three strains of fungi that are commonly found on moldy food or damp buildings: Aspergillus niger, Penicillium chrysogenum, and Penicillium simplicissimum.

"We selected these strains of fungi because they have been observed to be effective at extracting metals from other types of waste products," Cunningham says. "We reasoned that the extraction mechanisms should be similar, and, if they are, these fungi could probably work to extract lithium and cobalt from spent batteries."

​In order to start the process, the team pulverizes the cathodes and then exposes this to the fungus. Fungi naturally create an acid that isolates metals. So far, the researchers have found that oxalic acid and citric acid work best, managing to extract up to 85% of the lithium and 48% of the cobalt. This is not as effective as traditional methods for extracting the metals but the researchers believe it should be worth it because this method is much more sustainable. Another problem is that, once the metal is extracted, it is still in liquid form and is mixed with the acid created by the fungi.

Of course, in the end, the idea is still being tested and developed. Cunningham and his team plan on testing more varieties of fungi and have possible ideas on how to take the metals out of liquid state. Research like this is one of many small steps toward a more sustainable and eco-friendly future.

Sources: Fungi recycle rechargeable lithium-ion batteries, Mold Might Be The Future Of Recycling For Rechargeable Batteries, Projection of total worldwide lithium demand from 2015 to 2025 (in metric tons of lithium carbonate equivalent)

Photo credit: AMERICANVIRUS via Foter.com / CC BY-NC-SA

Photo credit: Don McCullough via Foter.com / CC BY-NC