Antoine Allanore

Professor of Metallurgy

Using electricity to transform metals processing

Using electricity to transform metals processing

Antoine Allanore, associate professor of materials science and engineering, researches integration of metals processing and extraction with power and chemical processing to create combined efficiencies.

By: Steve Calechman

Anything to do with metals, from discovery to distillation, requires intensity. It doesn’t always mean efficiency. It’s certainly not always green, and it can be exclusive because not every region or company has the resources. The process also poses something of a dilemma in terms of innovating versus controlling costs, since on one side labor wants to be paid, on another customers want low prices, and on another automation can only streamline so much. That bottleneck inspired Antoine Allanore to ask, “Where are we going to be able to reach the next transformation in metals extraction?”

It’s in energy, says the associate professor of materials science and engineering. And through his work, he’s developing technology that can integrate less expensive electricity. The end result would be to allow processing and extraction of metals in integration with power and other chemicals, in a way that’s better for the environment while still being efficient and productive. As for just one of the possibilities, Allanore says, “Imagine a facility that would not only use electricity when you are not at home, but would also be able to idle or even return electricity to the grid when citizens are in need of it.”

Where are we going to be able to reach the next transformation in metals extraction?

Banking on Electricity

In one of his projects, Allanore is looking to convert and recover non-ferrous metals, most specifically copper, by integrating with more electricity. The hope is that it will lead to greater accessibility, because in the current state, processing needs to be done in a primary facility, and in the United States, that facility has to be paired with a mine. If a company doesn’t have both, it can’t participate economically in the copper supply chain or meaningfully recycle copper-containing wastes.

The other challenge is the cost. As Allanore says, metals have to be affordable. People will only pay so much, but they also want to see less environmental impact. It doesn’t leave a lot of options, but cheaper sources of energy hold great possibilities, and for him, electricity has been the target.

It offers a two-pronged approach: reduce waste materials coming out of reactors and increase efficiency in using just the energy needed. In the past, he developed electrochemical reactors for iron production by electrolysis, reactors currently at the forefront of carbon-free steelmaking. Currently, in his lab, the attention is on cooper and similar metals, like nickel, cobalt, platinum, silver or gold, and he and his team have developed reactors at the scale up to 10 kilograms a day, using synthetic materials to mimic the process and establish the parameters of operations and cost.

It’s promising, but every mine, stream and sometimes metal has its own specificity, he says. In order to demonstrate and evaluate how the reactors work with actual supplies, Allanore is looking to find industry partners to run them with their materials at their scales. Ideally, it would be companies with both the current needs and the desire to eventually handle streams that might be deemed unconventional or difficult. Ultimately, it’s about defining the future of the field, and as he says, “Now is the time to basically go for it.”

Taking on the Overlooked Materials

Allanore has also developed a minerals separation process for metal compounds. It’s a unit operation that can selectively convert valuable metals that aren’t usually mined because of low concentrations or a hard-to-process form. For that, he and his team have a reactor that can work on solid streams and deliver materials that can be separated using conventional techniques, such as density or magnetic separation, to recover the metal compounds.

The prospect is exciting, he says. The unit doesn’t require electricity to be available and because it’s based on existing separation technologies, it can be deployed into an existing plant within two years and start transforming operations.

As an example, the reactor would be able to recover copper that’s present in slag at 1-2 percent concentrations and as microscopic particles (less than 10 microns). At present, it’s not feasible to liberate and/or break down particles to this size. Allanore’s unit would react to these streams and allow a new copper phase to form and grow bigger. The result is that grinding wouldn’t have to be so fine – maybe around 100 microns – before conventional separation technologies could be used.

He calls his reactor an “enabler” of well-known physical separation technologies and is transferable across metals, particularly battery materials, such as nickel, cobalt, manganese, and lithium, which are used in electric vehicles and don’t have cost-effective technologies to separate and reuse those metallic elements. This technology could do that, and the applications could go in many directions. A partner’s needs could dictate it, but the hope is to scale up quickly and the intent is to “impact the outside world,” he says. “We’re stepping into a new field of minerals separation.”

What the Future Also Needs

Responding to intermittency will be key, Allanore says. The current mindset with processing goes something like this: X amount of a certain material has to be produced 24 hours a day, 365 days a year in order to be cost-effective. But that approach isn’t efficient or practical. The sun doesn’t always shine. Natural disasters occur, and the pandemic has been a worldwide example of how supply chains can be upended.

He says that technology like his will allow smaller regions and companies to compete. By using electrons rather than hydrocarbons, it’s possible to reach the high temperatures needed for metals processing and be able to ramp them up and down quickly. This would allow a plant that, for example, works with copper to produce its main product, but when times are difficult, it could contribute energy, materials, even heat to its local communities.

It ties into the ultimate direction of making solutions integrated and regionally-based. Allanore’s work in Brazil developing potash has highlighted that. Farmers are spread out across the country and everything they export has to make it to the ports, requiring that crops travel well. Since there’s no national supply of fertilizer, that has to come in through the ports, as well.

You need to find an integrated, local solution that is independent, that is shielded from all situations in the global market.

The problem is that there’s no infrastructure, let alone a networked, distribution system, and as Allanore says, there probably never will be. The answer is producing local, sustainable fertilizer and having local energy resources. Farmers can be more cost effective and have better yields, and it might even influence what they decide to grow.

That approach to farming actually applies to processing materials in any location. “You need to find an integrated, local solution that is independent, that is shielded from all situations in the global market,” he says.