Some plant species accumulate raw materials in their tissues which are essential for future technologies.
The Sustainable Minerals Institute (SMI) at the University of Queensland (Australia) has teamed up with the state government to study what is known as phytomining. In this process, plants take up metals such as cobalt and zinc from the surrounding soil. These raw materials can then be extracted from the plant. One advantage of the process is that it has a much smaller impact on nature compared with conventional extraction methods. Even from the overburden of existing mines, valuable components can still be extracted by phytomining.
Dr. Antony van der Ent of the University of Queensland estimates that of the 300,000 known plants, only 700 have the hyperaccumulation capability needed for the process. Most of these plants accumulate nickel, which is needed for steel refining or batteries, among other applications. It will be some time before phytomining can be used on a large scale. But the results so far are encouraging, says van der Ent. He also points to a “metal farm” developed by the University of Lorraine in Malaysia. Per hectare, the farm produces 200 to 300 kilograms of the heavy metal annually.