Construction is planned for a pilot plant that will demonstrate a modular electrochemical technology for extracting rare-earth elements (REEs) and nickel from industrial wastes, such as coal ash. The startup Blueshift (Boston, Mass.; www.buildblueshift.com) recently announced venture capital funds that will allow the company to grow its staff and build a commercial pilot facility in the Boston area to start operations in mid-2026.
Blueshift has developed a process that couples two electrochemical reactions synergistically: one for extracting REEs from coal-ash waste; and another to simultaneously remove carbon dioxide from seawater (see diagram). The process relies on proton-coupled electron transfer (PCET), a concerted transfer of protons and electrons that is highly efficient and helps lower energy costs for the process.
“The reduction-oxidation (redox)-based process is similar in approach to a flow battery,” Blueshift co-founder and CEO Deep Patel explains. “Compared to other critical-metal-extraction methods, we are able to lower both capital costs, by eliminating the need for expensive precious metals, membranes and other hardware, as well as operational costs, by lowering energy costs with the efficient PCET.” The process lowers the energy costs compared to conventional REE extraction by a factor of ten, Patel says.
A key engineering issue that Blueshift has addressed in the development is the oxygen sensitivity of redox flow batteries, which has complicated efforts to make flow-battery processes economical. Capitalizing on technologies developed at the University of Michigan (Ann Arbor; www.umich.edu), the U.S. Dept. of Energy’s Advanced Research Projects Agency-Energy (ARPA-E; arpa-e.energy.gov), and elsewhere, Blueshift is able to mitigate the oxygen sensitivity issue for the electrochemical cell. By using additive manufacturing techniques to construct electrodes on inexpensive substrates, Blueshift minimizes the O2 exposure.
The planned pilot plant will aim to produce 1 ton/yr of REEs, targeting terbium and dysprosium, in particular, for the defense and semiconductor industries. And although the initial plant will use coal ash waste as input material, Blueshift’s technology can also extract REEs from mine tailings and can extract nickel from olivine mine sands.
The Blueshift process also involves removal of CO2 from seawater, resulting in high-purity calcium carbonate that can be sold to chemical-industry and building-materials companies, as well as carbon offset credits, which can be sold into cap-and-trade markets. The de-acidified seawater can help counteract ocean acidification.