Rio Tinto plans to produce critical mineral tellurium at its copper mine in Utah
(Kitco News) - Rio Tinto announced today that the company will begin construction on a new plant that will recover tellurium, a critical mineral used in solar panels, from copper refining at its Kennecott mine near Salt Lake City, Utah.
Rio Tinto said it is investing $2.9 million to set up the plant, which will recover tellurium as a byproduct of copper smelting, extracting a valuable mineral from waste streams. The plant will have a capacity to produce approximately 20 tonnes of tellurium per year.
Rio Tinto expects to begin production of tellurium in the fourth quarter of 2021, creating a new North American supply chain for this critical mineral.
The company noted that tellurium is an essential component of cadmium telluride, a semiconductor used to manufacture thin film photovoltaic (PV) solar panels. Thin films made of this compound can efficiently convert sunlight into electricity. Tellurium can also be used as an additive to steel and copper to improve machinability, making these metals easier to cut. It can also be added to lead to increase resistance to sulfuric acid, vibration and fatigue.
Along with producing almost 20 per cent of U.S. copper, Kennecott’s smelting process also recovers gold, silver, lead carbonate, platinum, palladium and selenium, while molybdenum is recovered from the Copperton concentrator. In total, nine products are currently recovered from the ore extracted at Kennecott.
Rio Tinto is a partner with the U.S. Department of Energy’s Critical Materials Institute (CMI) and works closely with CMI experts to discover further ways to economically recover critical mineral byproducts such as rhenium, tellurium and lithium.