Highly promising startup reveals first commercial-scale rare earth element refinery in the US.

Rising from the ashes, an American startup that was early in the field of rare earth element separation, Phoenix Tailings, has made a brilliant comeback with the announcement of the first rare earth refinery to begin production in the United States.

Founded in 2018, Boston-based Phoenix Tailings had a significant head start at the onset of the COVID-19 pandemic. Seeing the potential untapped value in the waste left behind in the refining of metals, the company sought to reclaim this waste, potentially revolutionizing the sector with modern sustainable practices.

Despite this advantage, with no background in mining, the company fell to the wayside as others had the connections and capital needed to kickstart their REE separation facilities.

As it is today, dozens of companies have begun to leverage economical and sustainable methods to recover the critical minerals and metals needed to provide for the ongoing green energy transition. However, it is evident that many are still sleeping on the veritable "gold" mine that is tailings ponds.

What are tailings?

The extraction of minerals from ore is generally done through two methods, placer mining – which uses water and gravity to concentrate valuable minerals – and hard rock mining – which pulverizes the rock containing ore.

For the more economical hard rock mining, a chemical reaction is necessary to concentrate the minerals, which is done through a process called comminution – grinding the ore into fine particles to facilitate extraction of the target material.

Due to this process, the remnant dust, powder, and fine grains (usually produced by a mill) are mixed with water, leaving a residue in the form of a slurry. Once the primary sought-after materials are extracted, these leftovers or tailings are historically considered worthless to a mine operator.

Typically stored in a designated safety zone, often a containment area known as tailings ponds, many of the largest miners in the world have millions of cubic meters of slurry material sitting around with nowhere to go and often present a constant risk of failure due to the immense weight of the liquid-like material.

According to Visual Capitalist, it is estimated that roughly 217 billion cubic meters (57 trillion gallons) of mine tailings exist around the world, as of 2021.

Seeing the immense potential of all this waste material, Phoenix Tailings opted to do something about it.

From mining "ashes"

Each year, the mining industry produces more than 172 billion metric tons of waste material that is thrown away.

According to Phoenix, this is enough tailings and other waste to cover the entire state of California in a foot-deep worth of sludge.

The tailings stored in ponds and other containment facilities, however, often host a suite of metals that are not captured while recovering the target resource. Many of these discarded metals are now considered critical to the technologies powering renewable technologies.

It is estimated that the tailings disposed of by mining companies contain upwards of US$112 trillion worth of raw materials, with just one percent of that value being enough to make a Fortune 500 company, according to the company.

Among the most common examples of this potentially valuable waste comes from the process of aluminum refinement; the residue becomes something known as bauxite residue or "red mud."

For every ton of alumina produced, nearly 2 tons of this red mud is left behind – for perspective, a Tesla car is made up of about 1 ton of aluminum, yet this produces roughly 3 to 4 tons of red mud.

Phoenix Tailings' initial beachhead market was primarily focused on red mud, a process that would extract iron, titanium, aluminum, silica and rare earth elements, as well as clean up these bygone storage ponds.

Keeping relatively low-key for the last several years, the company has made a magnificent comeback in the market desperately needed to power the green future.

Phoenix rare earths

Leveraging its proprietary process that can produce rare earth elements with zero toxic byproducts and zero direct carbon emissions, Phoenix Tailings has been able to significantly expand its rare earth refinery through funding from the Department of Energy's ARPA-E program, as well as financing from several key investors.

Already demonstrating its product viability at the pilot scale in its research facility, this new refinery to be built in Massachusetts will now focus on commercial scale, which is estimated to be capable of producing roughly 120 metric tons of rare earths per year, with a particular focus on the highly sought neodymium and dysprosium needed for the magnets powering electric vehicles, wind turbines, and other electric motors.

"We have a goal of a clean, electrified future, but we are currently relying on a supply chain dominated by a Chinese monopoly that produces critical metals like rare earths with a process so toxic, it is prohibited in the US," said Phoenix Tailings Chief Technology Officer and co-founder Tomas Villalón Jr. "Our rare earth refinery uses the waste known as tailings that have been left behind at mining sites around the country to produce rare earths with zero toxic byproducts and zero direct carbon emissions."

In its beginnings, Phoenix Tailings was aware that each type of tailings has many different types of metals; while initially focusing its efforts on bauxite residue, the company has dealt with platinum tailings, gold tailings, as well as copper, nickel, and iron.

All across the board the company's system has been successful, as it was constructed from scratch, allowing it to be dynamic and flexible for any individual feedstock.

This is accomplished with a closed-loop system that leaves behind nothing but a sand-like remnant, purportedly reducing over 70% of the tailings volume and extracting the value from it.

Using three separate processes of hydrometallurgy, solvometallurgy and electrometallurgy, Phoenix can tailor its extraction systems to purify the waste, obtain the untapped value in the discarded material and clean up the toxic pools at the same time.

With the backing and funding from both private and government, the once highly promising reclamation technology has made a resounding advance back into the spotlight. With the possibility now commercially available to clean up mine sites' tailings, more than just ESG standards, this opens up the possibility of permitting in new ways if a tailings pond becomes a stockpile rather than a near-permanent dump site.