The Hidden Treasure in Fossil Fuel Waste: Rare Earth Elements Worth Billions
Did you know that the waste left over from spent fossil fuel could potentially hold a treasure trove of rare-earth elements worth billions of dollars? In a groundbreaking 2024 study, geologists revealed that the ash produced from burning coal in fossil fuel power plants may contain up to $165 billion worth of rare earth elements, with $97 billion of that amount being feasibly extractable.
Researchers from the University of Texas at Austin have been working tirelessly to recover these valuable elements, suggesting that this could provide the US with a domestic source of critical materials without the need for extensive mining or dependence on imports, which currently supply the majority of rare-earth materials in the country.
Geologist Bridget Scanlon from the Jackson School of Geosciences emphasized the significance of this discovery, stating, “This really exemplifies the ‘trash to treasure’ mantra. We’re basically trying to close the cycle and use waste to recover valuable resources while also reducing environmental impacts.”
Rare Earth Elements: The Key to Modern Technologies
Rare earth elements, or REEs, are a group of 17 elements crucial to numerous industries and technologies, including batteries, wind turbines, electric cars, and smartphones. These elements are classified as “critical minerals” in the US, highlighting their importance in the modern world.
Despite their significance, the US currently relies heavily on imports for rare earth elements, with a substantial portion coming from China. However, recent research has suggested that the vast amounts of coal-ash waste produced by US power plants since the 1950s could harbor a hidden deposit of REEs.
When coal is burned, the non-combustible residue left behind contains trace amounts of REEs, which are significantly more concentrated than in unburnt coal. While the concentrations in coal ash are lower than in commercial ores, extracting these elements from the waste could prove to be a valuable endeavor.
Unveiling the Potential of Coal Ash
Co-led by Scanlon and geologist Robert Reedy, the research team estimated that accessible coal-ash deposits between 1985 and 2021 could hold up to 11 million tons of REEs, significantly surpassing current US reserves. The total theoretical value of these elements in all US coal ash amounts to $56 billion, with a substantial portion being feasibly extractable.
While the extraction methods are still under investigation, the potential value of recovering REEs from coal ash is undeniable. The researchers believe that this could not only enhance energy security in the US but also offset the costs of remediating environmentally vulnerable ash disposal sites.
As scientists and government agencies continue to explore the possibilities of extracting rare earth elements from coal ash, the global potential of this approach is also being considered. With other innovative methods such as phytomining and volcanic sources on the horizon, the future of rare earth element extraction looks promising.
The original research on coal ash and rare earth elements was published in the International Journal of Coal Science & Technology in November 2024.
