A green and efficient new rare earth mining technology that uses electricity instead of chemicals has been proposed.
Who
Researchers from the Chinese Academy of Sciences’ Guangzhou Institute of Geochemistry proposed a new approach in the Nature Sustainability journal earlier this month, showing that employing electrokinetic mining techniques to extract rare earth elements from weathering crusts can be both clean and economical.
Their experiments at various scales suggest that generating an electric field at the top and bottom of a volume of soil generates an electrokinetic effect, which accelerates the migration of REEs (rare earth elements), supposedly reducing the need for harmful chemical agents.
Why it matters
REEs are essential to many modern technologies. The device you’re reading this from has several components that require them. As the name suggests, these elements are rare. More than 90% of global heavy REE demand is sourced from ion-adsorption deposits, which form within weathering crusts. However, conventional mining applies excessive usage of chemical agents to recover REEs from these deposits, not only exhibiting low efficiency but also polluting the environment.
The new approach claims more than just environmental benefits. An on-site field test suggests that electrokinetics can achieve a recovery efficiency of over 90%, an 80% decrease in polluting agent usage, and a 70% reduction in metallic impurities.
“The technology developed by the Chinese scientists appears highly promising, as it supports a reduction in the volume of rocks excavated in traditional mining. It doesn’t mean that we can completely abandon the use of quarries in developing deposits, however.
High energy costs, periodic shutdowns of Chinese power plants resulting from air pollution, and shutdowns imposed on manufacturing sites in order to reduce coal consumption present additional risks. Improvements are therefore required and we should not anticipate a widespread rollout of the technology just yet” – Comment by Leonid Khazanov / Consultant – Metals and technologies // Science columnist specializing in metals, the fuel and energy sector, and industry trends. PhD in economics. Consults foreign companies on investments in Russian mining locations and factories. 
