Rio Tinto recovering lithium from Boron
"Twenty Mule Team" will soon deliver critical battery metal Metal Tech News – April 8, 2021
Last updated 4/20/2021 at 2:56pm
Recovering scandium from its iron-titanium mine in Quebec, tellurium from the Kennecott copper mine in Utah, and now lithium from its Boron mine in California, Rio Tinto is leveraging its operations to produce the critical metals needed for 3D printing, solar energy, and lithium batteries.
On April 7, the global miner announced that it has begun producing battery-grade lithium from waste rock at its Boron mine site at the western edge of the Mojave Desert.
The mine is operated by U.S. Borax, a Rio Tinto subsidiary best known for its "Twenty Mule Team" that would transport borates from the mine through the desert to customers, including the cleaning product that brandishes the slogan.
While the desert mine continues to supply nearly half the world's demand for refined borates, the discarded waste from this mining holds another treasure in a world transitioning to electric vehicles and renewable energy.
"A few years ago, we started looking into what metals we could extract from our waste," said Alex Macdonald, a senior engineer at the Boron mine. "We were looking for gold... but we found something better than gold: battery-grade lithium – and the potential to produce a lot of it."
A team at Boron has developed a breakthrough lithium process to recover the critical mineral and extract additional value out of waste heaps that have been piling up from more than 90 years of mining.
An initial small-scale trial in 2019 successfully proved the process of roasting and leaching waste rock to recover high grades of lithium.
Rio Tinto has now taken the next step into scaling this process up to commercial production, a demonstration plant designed to produce 10 metric tons of battery-grade lithium per year.
The demonstration plant, now in operation will be run throughout 2021 to optimize the process and inform Rio Tinto's feasibility assessment for progressing to a production scale plant with an initial capacity of at least 5,000 metric tons, enough to make the batteries for 70,000 electric vehicles, per year.
"This is a valuable next step in scaling up our production of lithium at the Boron site, all from using waste material without the need for further mining," said Rio Tinto Minerals Chief Executive Sinead Kaufman. "It shows the innovative thinking we are applying across our business to find new ways to meet the demand for emerging commodities like lithium, which are part of the transition to a low-carbon future."
Rio Tinto may also be producing lithium and borate at its Jadar project in Serbia. A feasibility study that details the design and economics of the proposed lithium-borate mine is expected to complete by the end of 2021.
Development of the lithium project at Boron draws on Rio Tinto's long-standing partnership with the U.S. Department of Energy's Critical Materials Institute, which is focused on discovering ways to economically recover critical mineral byproducts from existing refining and smelting processes.
For more information on other Rio Tinto initiatives to recover byproduct critical minerals and metals read Rio Tinto to produce tellurium in the US in the March 10, 2021 edition of Metal Tech News and Rio Tinto moves into scandium market in the January 20, 2021 edition of Metal Tech News.