Metal is a material that has made a strong indentation into our world–from being a part of the phones we use to making up medical equipment. While metals are most commonly found through mining the Earth’s crust, a new method of accessing it has recently emerged. This method is called phytomining, the process of extracting minerals from hyper-accumulating plants.
Phytomining is an environmentally friendly way to revolutionize the mining industry. Specific plants, over time, absorb metals like nickel, zinc, cobalt, and gold from the soil. With 320,000 recognized plant species, only around 700 plants are considered “hyperaccumulators.” One place with phytomining production is Malaysia’s Kinabalu Park. This location is a nickel mine with heavy machinery and four acres of a green shrub, scientifically called rufuschaneyi. When you slice open the plant, a juice emerges. This sap is one fourth nickel.
The mine in Kinabalu Park started from a research trial to prove the principle behind phytomining. Recently, its success has caught the attention of other mining companies nearby. “We can now demonstrate that metal farms can produce between 150 to 250 kilograms of nickel per hectare (170 to 280 pounds per acre), annually,” said Antony van der Ent, a senior research fellow at Australia’s University of Queensland whose work helped initiate the Malaysia trial.
Rufus Chaney, an agronomist at the U.S.Department of Agriculture, invented the word “phytomining.” He, along with a botany professor named Dr. Baker initiated the first trial for phytomining in 1996. Because of Mr. Chaney’s work, his name is the denomination of Kinabalu Park’s local shrub.
The applications of phytomining are endless. Nickel is an important ingredient in stainless steel and is constantly in demand. Hyperaccumulators such as rufuschaneyi benefit from absorbing the nickel because nickel can induce the absorption of potassium and help fight off pests. Additionally, phytomining could solve big issues in the mining industry. These problems include abandoned mines. Planting hyper-accumulators in leftover mines could help to absorb the remaining metals, leading to less waste and more revenue.
Phytomining is also sustainable. In the mining industry, extracting nickel normally induces intense energy from fossil fuels. Millions of dollars might be used for a site with only 1 percent nickel. Contrastingly, plants on a nickel farm can be harvested without acidic waste. Once the soil is stripped of nickel, the land can still be used for vegetable crops.
While the prospects for the nickel crop in Malaysia are huge, a drawback is the possible push for using tropical forests for cultivation. This is similar to a situation with palm oil, where the crop devastated Borneo’s forests.
Phytomining is a relatively recent development that continues to show the beauty and impact of mother nature. While it does not go without its risks, phytomining could completely alter the course of metal extraction in the years to come.
Written By: Sudeepthi Ravipati
November 25, 2021