Using the redox properties of tetratiometallates, the Polytechnic of Zurich explains how to recover rare lands in just a few steps
The problem of imports from China drives science to look for strategies to recover rare lands
The mine hidden in common use products can become a source of new raw materials useful for the energy transition. All you have to do is recover the rare lands that they keep. These 17 metals are essential in smartphones, computers, screens, batteries, electric motors and wind turbines. However, their extraction and separation are highly complex and harmful to the environment. Which makes them expensive in economic and environmental terms.
Europe is almost entirely dependent on imports of rare earth from China, which governments dislike. The attempt is to develop sustainable methods to recover rare lands urgently. The problem is that we start from scratch. But now, a team of researchers at ETH Zurich is trying to answer. In an article on Nature, he presented an innovative and simple method for separating and recovering Europe, one of the rare earth metals, from complex mixtures.
The key to this new technique lies in tetra-metallates, small inorganic molecules of four sulphur atoms surrounding tungsten or molybdenum. Their redox properties help reduce Europe to its bivalent state, facilitating its separation from other trivalent metals. This method is much more efficient than traditional separation processes, allowing you to obtain Europium in significantly higher quantities in a few simple steps.
The team’s new recycling approach is significantly more environmentally friendly than conventional extraction methods. If applied to electronic waste, it could turn fluorescent lamp waste into an urban mine in Europe, reducing dependence on imports.
Mougel and his team have patented this technology and are launching a start-up called REEcover to market it. They are also working to adapt the separation process to other rare earth metals such as neodymium and dysprosium, which are found in magnets, thus contributing to a more sustainable and circular use of these precious resources.
