The Kennecott integrated copper mining operation is located near Salt Lake City, Utah.
Estimated to entail an investment of $2.9m, the new plant will be equipped to recover tellurium as a by-product of copper smelting, extracting from waste streams.
The new plant, which will have around 20 tonnes of annual production capacity of tellurium, is planned to commence operations in the fourth quarter of this year.
“Adding tellurium to our product portfolio provides customers in North America with a secure and reliable source of tellurium produced at the highest environmental and labour standards with renewable energy.
“Rio Tinto is committed to using innovation to reduce waste in our production process and extract as much value as possible from the material that we mine and process.”
Tellurium is said to be a vital component of cadmium telluride, which is a semiconductor used to manufacture thin film photovoltaic (PV) solar panels. It can be added to lead to improve resistance to sulfuric acid, vibration and fatigue.
Utah Governor Spencer Cox said: “With abundant natural resources, Utah is ideally positioned to help supply the critical minerals essential to maintain American manufacturing competitiveness.
“Rio Tinto ’s smelter at Kennecott is one of only two that is capable of producing copper and other critical minerals. The new tellurium plant is another valuable contribution to critical mineral independence and energy security in the U.S.”
In partnership with the US Department of Energy’s Critical Materials Institute (CMI), Rio Tinto is currently working to find further ways to economically recover critical mineral byproducts such as rhenium, tellurium and lithium.