Breaking down rare earth element magnets for recycling

Discarded electronics, including old smartphones and non-functional laptops, harbor a wealth of rare earth elements (REEs), but extracting these valuable materials has proved challenging. Recently, a group of researchers announced a breakthrough method that simplifies the recovery process of REEs from waste magnets, making it more energy-efficient and significantly less polluting compared to traditional techniques. Their findings, published in the Proceedings of the National Academy of Sciences, outline a process that utilizes an electric current to rapidly heat waste magnets to extremely high temperatures. This innovative approach incorporates chlorine gas to interact with non-REE components, allowing them to remain in a vapor state, thereby separating them from the desired materials. James Tour, a materials science and nanoengineering professor at Rice University and one of the study’s authors, emphasized the importance of this research in addressing the United States' growing demand for REEs. "The country is racing to find ways to obtain these elements," he stated. "Our waste is a ready resource; we just need to extract it." In a previous study in 2018, Tour and his team pioneered flash joule heating, a technique that converts various carbon sources into graphene, a strong and conductive material. Expanding on this concept in 2023, they combined flash joule heating with chlorine to create a method that identifies the Gibbs free energy and reactivity of all 17 REEs along with nine common oxides found in REE waste. The process involves placing shredded waste magnets on a carbon platform within a glass chamber, where an electric current generates intense heat in seconds. This is followed by the introduction of chlorine gas, which forms chlorides of undesirable elements such as iron, effectively reducing their boiling points and facilitating easier extraction of REEs.