Business Update: September 2022

Making magnesium from nickel waste

Australian start-up, Latrobe Magnesium, has announced that Bechtel will be doing a feasibility study at its potential 100,000 ton per year magnesium production site in Victoria, Australia.

Setting the scene. Up until the late 1990s, the U.S. was the world’s leading producer of magnesium. That’s because Dow pioneered the means to extract it from seawater via electrolysis with a small amount of calcium oxide. Things changed in the early 21st century after China commercialized the Pidgeon process — a process that crushes dolomite and ferrosilicon, heats them in a furnace, and distills gaseous magnesium metal off the top.

So, what’s the deal here? Latrobe Magnesium has been talking about producing magnesium metal from waste sources (like fly ash from coal power plants) and ferronickel slag (from nickel production). Their process involves the hydrometallurgical extraction of the metal from ferronickel slag followed by thermal reduction. Making magnesium like this should produce about 3% as much CO₂ as the Pidgeon process.

The bigger picture. Right now, the largest driver for magnesium demand is to lightweight vehicles (the metal weighs one-third as much as aluminum), and the largest driver for nickel demand (that’s where the ferronickel slag comes from) is to make cathodes for lithium-ion batteries (for electric vehicles). So, if Latrobe’s process is feasible from a cost and technical point of view, this may be something worth noting...