Rare-earth magnets recycling process simplified

June 25, 2015 0 By John Max

The new process to recycle rare-earth magnets could make the electronic industry more sustainable.

American researchers from the University of Pennsylvania have developed a new recycling process, which focuses on reprocessing two types of rare earth metals, neodymium and dysprosium, which are commonly used as magnets in a variety of electronic devices, and are both equally difficult to find in nature and can only be extracted via a complex method that is also damaging to the environment.

The new reprocessing method is surprisingly uncomplicated.

According to Engineering and Technology Magazine, in addition to being simple, the method of recycling created by the researchers requires the use of only standard laboratory equipment and works almost immediately at room temperature.

Furthermore, instead of requiring the use of natural ores, the process recycles the two metals from devices that have been discarded. Since this is the case, the researchers feel that their recycling method would be much cheaper and more environmentally friendlier than the traditional extraction techniques currently used.

Recycling - neodymium magnetThe lead author of the study, Eric J. Schelter, said that “It’s, in principle, easier to get the neodymium and dysprosium out of technology than it is to go back and mine more of the minerals they are originally found in.” Schelter added that “Those minerals have five elements to separate, whereas the neodymium magnet in a wind turbine generator only has two.”

The recycling process involves the separation of these two metals so that they can be reused for future applications.

Both neodymium and dysprosium are very important to the electronics industry. Schelter explained that neodymium magnets can perform at an array of temperatures. When dysprosium is added into these magnets it improves the neodymium magnet’s thermal qualities. However when recycling these magnets so that they can be reused, it’s essential that they are separated. The reason is that different applications require different ratios of each metal.

The goal of the researchers was to simplify rare earth metal separations and improve the efficiency of the process. However, instead of using the liquid-liquid method, which is a complex process that entails dissolving the composite material and chemically filtering the elements to separate them, the research team came up with their own solution.

The two metals are separated by using a solution to dissolve the neodymium and leaving the dysprosium behind as a solid. According to Schelter, with the right ligand, his team’s separation method can take five minutes, while the liquid-liquid extraction method can take weeks.

Since this chemical technology can immediately separate these metals, it means that smaller scale recyclers can use it to attain value from their materials, which would otherwise be out of the question if they had to rely on the industrial-sized liquid-liquid recycling method.