A team of scientists in China has made a groundbreaking discovery: the fern species Blechnum orientale can naturally accumulate rare earth elements (REE) from the soil. This finding, detailed in a study published in the journal Environmental Science & Technology, suggests a potential new method for obtaining these essential materials without resorting to destructive mining practices.
Rare earth elements are vital for the production of numerous technological devices, including electric vehicles, smartphones, and wind turbines. Traditionally, extracting REEs involves extensive mining and processing, which can lead to significant environmental degradation, including topsoil destruction and water pollution. The new research offers an alternative approach that could mitigate these issues.
Researchers led by geochemist Liuqing He from the Chinese Academy of Sciences discovered that B. orientale can crystallize REE minerals within its tissues even under ordinary environmental conditions. This contrasts sharply with the conventional understanding of how these minerals form, which typically requires high temperatures and pressures found deep within the Earth.
The study highlights that B. orientale is classified as a hyperaccumulator plant, capable of thriving in soils with high concentrations of heavy metals. These conditions would usually be toxic to other plant species. Liuqing He explained the significance of this fern’s ability, stating, “This fern can facilitate REE mineralization, specifically the mineral monazite, which was previously only known to occur in rocks subjected to extreme geological conditions.”
Monazite is a prominent source of rare earth elements, and the researchers utilized advanced microscopic imaging and chemical analysis techniques to study the fern specimens collected in South China. Their findings suggest the feasibility of a process called phytomining, which involves using plants to extract metals from the soil. This method could revolutionize the way REEs are sourced and potentially alleviate the global competition for these critical resources.
In electric vehicles, elements such as neodymium, dysprosium, and praseodymium are essential for the powerful permanent magnets that drive the motors. Additionally, REEs play a crucial role in various components of smartphones, including displays, speakers, and camera lenses. While the current yield of REEs from B. orientale is not substantial, the research opens up exciting possibilities for future exploration into phytomining.
The next steps for the research team involve determining whether B. orientale is unique in its ability to extract REEs or if other plant species can also perform this function. They aim to develop efficient methods for extracting the monazite and breaking it down into its constituent rare earth elements without significant loss of material.
“This discovery reveals an alternative pathway for monazite mineralization under remarkably mild conditions and highlights the unique role of plants in initiating such processes,” the researchers concluded.
The implications of this research could be significant, particularly as countries worldwide strive to secure reliable supplies of rare earth elements in light of China’s current dominance in the REE supply chain, controlling approximately 70% of global mining and processing capabilities. The potential for harnessing natural processes to source these materials could pave the way for more sustainable practices in the technology sector.
