Electric currents are expected to help minimize the use of chemicals while improving the efficiency of raw material extraction.
For decades, China has been the dominant player in rare earth production. The country’s ability to outperform previous competitors, such as the United States, was largely driven by less stringent environmental regulations and lower production costs. However, as demand for rare earth elements increases and geopolitical tensions rise, Western countries are working to strengthen their own resource supply chains. To protect its market leadership against growing competition, China is seeking to upgrade the quality of its rare earth industry, with new extraction methods playing a key role. One such method has recently been presented by a research team from the Chinese Academy of Sciences (CAS).
The new process is primarily designed for ion-adsorption clays, a type of deposit currently only mined in southern China and neighboring Myanmar, which is the primary source of highly sought-after heavy rare earths like terbium. These raw materials are traditionally extracted from rock through leaching, often using ammonium salts. In the innovative method, electric currents drive the movement of the extracted metals, leaching agents, and other substances such as water. According to the researchers, this approach is more environmentally friendly, faster, and more efficient.
The team first introduced the concept in 2023 (we reported). The feasibility of the method was confirmed through initial experiments. Since then, efforts have focused on addressing industry-related challenges, such as ensuring the stability of electrodes in corrosive environments. With the improvements made, the use of leaching agents has been reduced by 80%, and energy consumption has dropped by 60%. A 60-day industrial-scale test showed a recovery rate of 95% of the rare earths contained in the ore. The extraction process has also been significantly accelerated, and the impact on groundwater has been substantially reduced. The researchers have hailed their results as a breakthrough in enabling greener and large-scale mining of ion-adsorption clays.
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