Iowa State Improves Precious Metal Recovery

Novel process brings most reactive components to the surface (left) and traps the least reactive components at the core (right). (Courtesy Martin Thuo/Iowa State University)

Inspired by nature’s work to build spiky structures in caves, Iowa State University (ISU) researchers have developed a novel technology capable of recovering precious metals from the alloys in electrical waste, such as old phones, computers, and televisions. University start-up funds and part of a U.S. Department of Energy Small Business Innovation Research grant supported development of the technology.

At relatively low temperatures, oxygen is introduced, slowly moving most reactive surfaces to the surface forming stalagmite-like spikes of metal oxides.  The least-reactive components remain in a purified, liquid core surrounded by brittle metal-oxide spikes “to create a so-called ‘ship-in-a-bottle structure,’” said Martin Thuo, the leader of the research project and an associate professor of materials science and engineering at ISU.