Phytomining: Using Plants to Mine Valuable Metals From the Soil With Their Roots

Image Credit: Nickel hyperaccumulator Alyssum argenteum / David Stang via Wikimedia Commons

By Edd Gent at Singularity Hub: The renewable energy transition will require a huge amount of materials, and there are fears we may soon face shortages of some critical metals. US government researchers think we could rope in plants to mine for these metals with their roots.

The concept of phytomining has been around for a while and relies on a class of plants known as “hyperaccumulators.” These species can absorb a large amount of metal through their roots and store it in their tissues. Phytomining involves growing these plants in soils with high levels of metals, harvesting and burning the plants, and then extracting the metals from the ash.

Green technologies like solar power and electric vehicles are being adopted at an unprecedented rate, but this is also straining the supply chains that support them. One area of particular concern includes the metals required to build batteries, wind turbines, and other advanced electronics that are powering the energy transition. We may not be able to sustain projected growth at current rates of production of many of these minerals, such as lithium, cobalt, and nickel. Some of these metals are also sourced from countries whose mining operations raise serious human rights or geopolitical concerns.

To diversify supplies, the government research agency ARPA-E is offering $10 million in funding to explore “phytomining,” in which certain species of plants are used to extract valuable metals from the soil through their roots. The project is focusing on nickel first, a critical battery metal, but in theory, it could be expanded to other minerals.

“In order to accomplish the goals laid out by President Biden to meet our clean energy targets, and support our economy and national security, it’s going to take [an] all-hands-on-deck approach and innovative solutions,” ARPA-E director Evelyn Wang said in a press release.

More here.