Fast Metals is rethinking one of industry's most overlooked byproducts: red mud, the iron-rich residue left behind in aluminum refining. The startup says this material, often stored in large open-air piles, can be transformed into a valuable feedstock for extracting critical minerals.
Founded by Sumedh Gostu, the company has raised a $4.3 million pre-seed round led by New Climate Ventures, with participation from Azolla Ventures, Astor Swiss, and Rio Tinto's accelerator, Founders Factory. The funding is set to support the next stage of scale-up.
Red mud contains more than iron oxide. It also holds titanium, aluminum, and rare earth elements, but these have traditionally been difficult to separate economically. Fast Metals says its method changes that equation by using a chemistry-driven process that relies in part on another industrial waste stream from alumina refineries.
According to the company, the material moves through six processing stages, with different minerals recovered along the way. The model is designed so that iron helps cover operating costs, while higher-value outputs create the upside.
Gostu developed much of the approach during doctoral research at the Colorado School of Mines. He later refined the concept with co-founder Anthony Staley, identifying a waste input that could make the process more commercially viable.
The startup is now preparing for a commercial contract with Metalox, a mineral processor, to treat one ton of red mud and refinery waste per week later this year. If the approach scales, it could help turn industrial residue into a more circular supply of materials for future manufacturing and clean-tech industries.
