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A D V A N C E D M A T E R I A L S & P R O C E S S E S | O C T O B E R 2 0 1 9 1 1 They call their method ultrafast pulsed laser welding. “By focusing the energy right where we want it, we avoid setting up temperature gradients throughout the ceramic, and we can encase tempera- ture-sensitive materials without dam- aging them,” the researchers say. The process has so far only been used to weld small ceramic parts that are less than two centimeters in size. Future plans will involve optimizing the method for larger scales, as well as for different types of materials and geome- tries. ucsd.edu. MINING FOR RARE EARTH ELEMENTS IN ELECTRONIC WASTE Researchers at the DOE, Washing- ton, have invented a process to extract rare earth elements from the scrapped magnets of used hard drives and other sources. Rare earth elements are most often used in permanent magnets for clean energy. “We have developed an energy- efficient, cost-effective, environmental- ly friendly process to recover high-value critical materials,” says co-inventor Ra- mesh Bhave of ORNL. “It’s an improve- ment over traditional processes, which require facilities with a large footprint, high capital and operating costs, and a large amount of waste generated.” Through the patented process, magnets are dissolved in nitric acid, and the solution is continuously fed through a module supporting polymer membranes. The membranes contain porous hollow fibers with an extractant that creates a selective barrier, allow- ing only rare earth elements to pass through. The rare-earth-rich solution collected on the other side is further processed to yield rare earth oxides at purities exceeding 99.5%. No commercialized process cur- rently exists to recycle pure rare earth elements from electronic-waste mag- nets. To ensure rare earths could be recovered across a wide spectrum of ORNL’s Ramesh Bhave recovers high- purity rare earth elements from scrapped magnets of computer hard drives and other post-consumer wastes. Courtesy of Carlos Jones/ORNL/U.S. DOE. feedstocks, researchers subjected mag- nets of varying composition—from sources including hard drives, mag- netic resonance imaging machines, cell phones, and hybrid cars—to the process. Industrial efforts needed to deploy the ORNL process into the marketplace, funded over two years by DOE’s OTT Technology Commercialization Fund, began in February 2019. energy.gov.