A molecule with a built-in electric charge could replace chemical reagents in recovering gold from e-waste

Researchers at the University of Illinois created a molecule that conducts electric current and cuts chemical reagent use by up to 100 times when extracting precious metals from electronic waste.

A research group led by professor Xiao Su, of the Department of Chemical and Biomolecular Engineering at the University of Illinois Urbana-Champaign, published a new molecule in July 2026, in the journal ACS Energy Letters, capable of replacing part of the chemical reagents used to recover gold from electronic waste. The work, led by postdoctoral researcher Deborah Schmitt, builds on a technique the same lab introduced in 2024, called electrochemically mediated liquid-liquid extraction (e-LLE), which already used electricity to reduce the use of acids and bases in metal extraction — but still relied on complementary chemical reagents to work. The new molecule eliminates much of that dependence: it carries a permanent built-in electric charge, making it directly controllable by electric current, without needing a chemical intermediary to carry the charge. The research was funded by the US Department of Energy, under the Office of Science's Separation Science program.

The technical advance here isn't extracting gold from electronic waste — that already exists, through conventional hydrometallurgical processes that depend on large volumes of acids, cyanide, or other aggressive reagents, which then become waste to be treated. What changes is where control of the process lives. In traditional methods, controlling extraction selectivity — separating gold from copper, from nickel, from other metals present in the same solution — requires adjusting the chemical composition of the bath, swapping reagents as the target metal changes. In the new technique, the molecule works like an electrolyte: since it already carries the electric charge built in, adjusting the applied electric current is enough to control which metal ions it binds and releases. It's the same kind of leap the battery industry made by swapping chemical control for electrical control across several processes — precision goes up, waste goes down, and the process becomes easier to automate, because electricity is simpler to measure and adjust in real time than chemical concentration. The 10-to-100-fold cut in reagent consumption isn't just an environmental gain: it's also a direct economic one, because selective extraction reagent is expensive and its disposal is regulated. And the reason this matters to mining, not just electronics recycling, is that the same chemistry applies to any source of metal dispersed at low concentration — including mine tailings, spent automotive catalysts, and other secondary sources that today are too expensive to process at scale.

For anyone working in mineral processing and the circular economy, this technique is still at lab scale, but it points to a clear direction: part of the next productivity gain in recovering critical metals won't come from mining faster, it will come from extracting with more selectivity from what's already been extracted. Cutting chemical reagent use also reduces the environmental liability of processing plants, a factor increasingly central to permitting and project financing. And for researchers and process engineers, it's a concrete example of how shifting control of an extraction process from chemistry to electricity can open the door to automation and scale that conventional hydrometallurgy doesn't allow as easily.