Scientists at Oregon State University have developed a more efficient, water-based method for separating zirconium and hafnium—two metals that are essential in the semiconductor and nuclear energy industries but are chemically very similar. The research, published in the Journal of the American Chemical Society, was led by graduate research assistant Alex Roseborough and May Nyman, a chemistry professor. This breakthrough addresses a long-standing challenge in materials science: how to effectively separate these metals, which are often found together in natural sources but require precise separation for industrial use. The new process uses an aqueous solution containing natural zirconium, trace amounts of hafnium, thiocyanate ligands that bind to the metal ions, and choline—a nontoxic chemical commonly used in food additives. The method relies on precipitation, a process where ions with opposite charges combine to form an insoluble solid. This allows for the separation of hafnium-rich species from the solution. The separation factor, a measure of how well two components can be separated, achieved by this method is 33—far above the industry standard of six to seven. Currently, only two U.S. facilities are capable of performing this separation on an industrial scale: ATI Specialty Alloys & Components in Albany, Oregon, and Westinghouse Electric in Ogden, Utah. These plants use millions of pounds of flammable organic solvents annually, a process that is both energy-intensive and environmentally harmful, with about 4% of the solvent lost to the air as noxious pollution. The new water-based method offers a potentially cleaner and more sustainable alternative. Nyman highlighted that the study provides detailed insights into the atomic-level mechanisms behind the separation process and shows how precipitation-based methods can rival traditional solvent extraction. These findings are particularly significant as the world shifts toward more sustainable and carbon-free energy sources, including nuclear power. The research, titled "Emergent Hf-Selective Precipitation of Aqueous (Zr,Hf) Thiocyanate Molecules through Nuclearity Control," was published in the Journal of the American Chemical Society in 2026.