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Rio Tinto says it can extract strategic mineral from metal plant processing waste

May 27 (Reuters) - Rio Tinto Plc said on Wednesday it has developed a process to extract the rare earth scandium from its titanium dioxide production process and is studying ways to commercially produce the mineral.

The move is the latest example of Rio taking a second look at the waste from its core mining business in an effort to reprocess it and produce so-called strategic minerals and rare earths, a grouping of 17 minerals used to make electronics.

China is the world's largest producer and consumer of many of these minerals, including rare earths. That has prompted efforts by politicians and companies in Canada, the United States and elsewhere to try and produce their own supplies.

Rio said it can now extract scandium oxide from the waste products generated when it makes titanium dioxide, a white pigment, at one of its facilities in Quebec.

The company's scientists had been studying ways to extract minerals from the waste and discovered high concentrations of scandium, which can be used in lighting and as a strengthening agent for aluminum.

Rio said scandium was the only rare earth element found in large enough concentrations in the Quebec plant's waste stream to produce economically.

Rio added it has started producing small batches of scandium oxide and is talking with potential customers to decide when to move into commercial production. Rio declined to forecast that timeline.

The move "is a great example of how we are looking at our operations across the world with fresh eyes to see how we can extract value from by-product streams," Rio Chief Executive Jean-Sebastien Jacques said in a statement.

Separately, Rio is also studying ways to extract lithium from waste rock at a California mine and is working with the U.S. Department of Energy's Critical Materials Institute on rare earths-related research. (Reporting by Ernest Scheyder; Editing by Steve Orlofsky)