St George eyes cleaner, cheaper niobium with US tech

St George Mining has rolled out another big-ticket partnership at its Araxá critical minerals project in Brazil, striking a strategic alliance with innovative metals processor Boston Metal to chase a cleaner, potentially cheaper pathway to niobium production. 

The company says it has signed a memorandum of understanding (MoU) with the Massachusetts Institute of Technology spin-out to test its patented molten oxide electrolysis technology on Araxá’s niobium material to assess its suitability for producing ferroniobium. 

Molten oxide electrolysis is an all-electric process designed to produce intense heat that renders metals directly from their oxides. St George believes the technology could deliver higher yields, simplify the processing flowsheet and, importantly, cut carbon emissions. 

It is a meaningful point of difference in niobium-land.  The traditional ferroniobium route typically starts with flotation to beneficiate the material, followed by leaching. The process is then finished off with an aluminothermic reduction, where aluminium powder acts as a reducing agent to convert metal oxides into pure metals or alloys, releasing intense heat. 

That approach typically converts niobium concentrate into ferro-niobium or chromium oxide into chromium to produce molten metal at temperatures often exceeding 3000°C. 

St George believes molten oxide electrolysis could simplify beneficiation and potentially eliminate those refining and conversion steps altogether, reducing cost, waste and emissions. 

St George Mining executive chairman John Prineas said: “The MOE technology offers the opportunity for St George to develop a new generation of niobium processing at Araxá. This could deliver cleaner and lower-cost production for us and our stakeholders. “Boston Metal is an industry leader in innovation for metals processing and we are delighted to have been selected to trial this opportunity to revolutionise niobium production.”

There may also be a rare earths kicker to this story. The company says the slag produced during niobium processing is also likely to carry a high concentration of rare earths, which could lower processing costs in a broader rare earths production flowsheet. 

The deal brings a high-profile name to St George’s table. Boston Metal says it has attracted more than US$500M in funding from a list of heavyweights, including BHP, BMW, Microsoft, ArcelorMittal, Vale and Aramco.

Additionally, the molten oxide electrolysis platform has picked up global recognition, including an S&P Global Platts Metals Award for new technology and two nods from TIME Magazine. 

Boston Metal is commissioning its first commercial plant in Brazil to produce high-value, critical metals such as niobium, suggesting the technology is beginning to move beyond the lab. The Brazil connection - apart from being serendipitous - could obviously be of great value to St George. 

Chief executive officer Tadeu Carneiro said Boston Metal welcomes the opportunity to deploy its molten oxide electrolysis technology to add value to St George and to advance clean, responsible metals production at its Araxá project. 

Under the memorandum, the parties will work together on a potential flowsheet for ferroniobium production using the molten oxide electrolytic technology, with each party funding its own workstream. 

Any longer-term licensing arrangement that might eventuate from the trials program would be subject to a separate formal agreement and for now, neither party is locked into exclusivity by the MoU. 

The Boston Metal tie-up follows hot on the heels of another Araxá processing move announced yesterday, when St George signed a memorandum of understanding with Spanish engineering heavyweight Técnicas Reunidas S.A to run test work on the project’s high-grade rare earths using its proprietary RARETECH technology.

Técnicas Reunidas has been appointed to lead the European Union-funded PERMANET project to establish the first European value chain for permanent magnet manufacturing. St George says the alliance could open up European markets to Araxá’s rare earths.

With drill rigs still on the march at Araxá and metallurgical testwork progressing on both traditional and new-generation routes, St George appears to be stacking its deck with partners that can help turn its giant Brazilian rare earths-niobium resource into a modern, lower-carbon critical minerals business.

Is your ASX-listed company doing something interesting? Contact: matt.birney@businessnews.com.au