How To Recycle Rare Earth Elements

IRA FLATOW: This is Science Friday. I’m Ira flatow, coming to you from Iowa State University in Ames.

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You have probably heard quite a bit about the importance of rare-earth elements, right, this group of 17 metals that are used in a wide range of things that make our modern lives possible, like batteries, and magnets, and LED light bulbs, phone screens, catalytic converters, just to name a bunch of them.

Well, these elements are essential to a new and green economy, but mining these metals is a dirty, complex and costly process. And as we continue our energy transition, the demand for these elements is going to continue to grow. So one of the possible solutions is to recycle them when they’re discarded in electronics.

But how do you get them out of the electronics? How do you recycle them? Well, my next guest has developed a new way to do just that, Ikenna Nlebedim is a material scientist at the Critical Materials Institute at Ames National Laboratory. Welcome to Science Friday.

IKENNA NLEBEDIM: Thank you for having me.

IRA FLATOW: And over here on my right, he’ll be doing the demonstration, is Dr. Denis Prodius, also a scientist at the Critical Materials Institute at Ames. Thank you for joining us today. OK, Ikenna. Let’s just jump right into this. How do you recycle stuff, like I’m talking about. What’s the technique that you use?

IKENNA NLEBEDIM: Well, I think that before we talk about the technique, it’s important to think about where these materials are used in terms of application. I’m sure that each of us here has a cell phone, definitely. And they’re using electronic devices, one of which is a hard disk drive, something like this.

IRA FLATOW: That’s a big hard drive.

IKENNA NLEBEDIM: It’s a big hard drive. At the end of life, typically, this is shredded.

IRA FLATOW: Shredded. You put this giant hard drive in a shredder.

IKENNA NLEBEDIM: And you shred it.

IRA FLATOW: So that everything is just turned into garbage.

IKENNA NLEBEDIM: It becomes a mixture of chemistry. But the reason it is shredded is because of data security.

IRA FLATOW: Data security. Yeah, you don’t want anybody reading your hard drive.

IKENNA NLEBEDIM: Exactly. But if it is shredded, now, how do you go about getting some thing that is about 1%, maybe 2% of the entire mass, in a way that is effective as well as economically deployable? And that’s where the complexity begins.

IRA FLATOW: You mean after it’s shredded? Wow. How do you do– OK, I’m listening. How do you do that?

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IKENNA NLEBEDIM: Keep listening. So the way it was done was to take the shredded stuff, and you do what they call magnetic separation, because the permanent magnets are magnetic. So you separate them, and then you take the magnetic stuff. You heat them up to, say, about 350 degrees Celsius to destroy the magnetism. And then you put them in acid, and you dissolve them and then begin the precipitation and so on. The problem is, you’ve already put many steps before you even start getting what you need.

IRA FLATOW: And you’re trying to pull the magnetic stuff out, the magnets.

IKENNA NLEBEDIM: Yeah. Trying to put the magnets, the rare-earth in the magnet.

IRA FLATOW: I see.

IKENNA NLEBEDIM: That’s what you are going after.

IRA FLATOW: OK, so you have come up with a–

IKENNA NLEBEDIM: We’ve come up better, different way.

IRA FLATOW: Tell us about that.

IKENNA NLEBEDIM: The way we’ve done this is that we take the shredded stuff, which is over there.

IRA FLATOW: Bottle of shredded– that’s shredded stuff.

IKENNA NLEBEDIM: Yep. And then you take this and you put them in solution as they are, without pre-separation. And the solution selectively dissolves the magnet. It leaves the aluminum undissolved, copper, gold, platinum. And those can head to other recycling steps.

Now, when you have this rare-earth in solution, you can precipitate it. Think about it this way. It’s like a cloth. You put it in a washing machine. We need the water, the dirty water. That’s where the rare-earth is. You can always wear your cloth, but we precipitate the rare-earth afterwards.

IRA FLATOW: And do you have did you find a magical, so to speak, way of doing this, that no one else had found? What kinds of magic are you using here?

[LAUGHTER]

IKENNA NLEBEDIM: It’s not magic. It is science.

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IRA FLATOW: All right, Denis. Denis, you want to show us what happened? That was the perfect answer you gave. So, Denis, tell us what’s going on here.

DENIS PRODIUS: OK, so we have copper sulfate solution. Actually, you can buy it on even Amazon, and we have shreds.

[LAUGHTER]

Sorry. Maybe it’s a secret information, but you can buy it on Amazon. Yes, so we have shreds, and we have copper sulfate. So I will just add copper sulfate here and shreds, and we will enjoy our show. And Mother Nature will do all the job.

IRA FLATOW: Go for it. So you’re going to pour it in into this bottle of shredded hard drive, and it’s going to extract those materials that we want from it. So how long is that going to take to do its thing?

DENIS PRODIUS: Usually, it takes in big scale, large scale, industrial scale, like three hours, four hours. But here, we will see probably in 20 minutes already effect. In the next five minutes, you will see how reaction starts. And after 20 minutes, you will see evident difference with what we had at the beginning and at the end. And after that, I will demonstrate how we recover it here. And I think it will be the largest event of recycling made together.

IRA FLATOW: Wow. Wow. And how different is this? You mentioned that this cuts out a lot of steps in the process. It goes right to the end product here?

IKENNA NLEBEDIM: So what you see in the big jar right there is the recovered material. So we eventually pull the rare-earths out. So that’s the one that Denis is holding now. And we pull the rare-earths out, and these rare-earths are ready to go back into the supply chain.

You can see that there is a company that is a few minutes from here, to TdVib, LLC, and they have another company called CMR. So they have already completed a pilot plant where they have started deploying the technology.

IRA FLATOW: Why are the magnets so important?

IKENNA NLEBEDIM: Very important question. You remember I talked about data storage.

IRA FLATOW: Right.

IKENNA NLEBEDIM: You think about electric vehicles. There are two key aspects of electric vehicles, maybe three. You have the battery. Then you have the electronics part of it, but you also have the model. If you want the model to be very efficient, you need the permanent magnets there. And they are important. They are used in different applications, including national security. In fact, that drone would not be able to fly very well efficiently without a permanent magnet.

IRA FLATOW: Speaking of permanent magnets, we can take your questions, if you want to make your way to the microphone and have questions about this. Yes, go ahead.

AUDIENCE: When you recover rare-earth elements from these electronic slurries, do you recover just one element or multiple elements that they then need to purify?

IKENNA NLEBEDIM: So when we recover these elements, there are a few of the rare-earth elements used in the magnet. So this would typically contain neodymium, praseodymium, and dysprosium. And so when you recover them, it’s a choice you need to make. These materials are already used to make magnets. Do you have to separate them to make magnets again? You don’t have to, but if you want to separate them, then you need to take them to the next step.

IRA FLATOW: And in the next step, once you’ve taken out the material you want, how do you separate the other valuable metals? Do you send that to someone else?

IKENNA NLEBEDIM: You can send, say, the aluminum and the gold to the smelters. But now, we have a funding from the US Department of Energy. And what they have asked us to do is to develop a system such that the waste doesn’t come to the recycling, but the recycling goes to the waste, which means we have modular systems, which would be at the point where the waste is generated such that those other components, they don’t need to come to us.

IRA FLATOW: Very clever to do that. Yes, over here. Question.

AUDIENCE: What is the efficiency of your yields for this new method compared to existing methods, and how can that eventually affect new mining of materials versus creating possibly like a self-moving recycling structure for these rare-earth materials?

IRA FLATOW: He’s either an economics major or an engineering major. Yes, how efficient is this? What’s the economics of this?

IKENNA NLEBEDIM: So when we began developing this technology, we reached efficiency of 70%,

IRA FLATOW: Seven oh?

IKENNA NLEBEDIM: 70, seven zero. And we celebrated it. We were so happy, because at the time , no other recycling technology was up to 50. But when it was the commercial, when we started the commercial deployment of it, it got to 90%. [APPLAUSE]

IRA FLATOW: I don’t know of anything that’s 90% of anything.

IKENNA NLEBEDIM: Well, I’m going to tell you one more. So 90%, that’s when it is in electronic waste. But if you have magnet swathes, like grinding swathes and scrap magnets, or pre-concentrated magnet, it is more than 98%.

IRA FLATOW: 98%.

IKENNA NLEBEDIM: Correct.

IRA FLATOW: And is this being commercialized as we speak?

IKENNA NLEBEDIM: Yes, the pilot plant is completed, and they are going forward with further development.

IRA FLATOW: Wow. I’m not going to ask how to buy stock in that company. Yes, let’s go ahead.

AUDIENCE: Hi there. First off, as a chemistry major, I can say, wow. I’m impressed by those percent yields. That is insane. Congratulations. But my question is, how do you make this economic compared to extracting virgin materials? Because the reality of it is, the companies that produce these electronics, if it’s not economic for them to use recycled materials, they won’t. How do you make sure this is something that can be scaled up to a point where it becomes economically viable?

IRA FLATOW: So let me begin with the last part of it. In terms of scaling, we scaled significantly. I think one of the last processes we did was about a ton per batch.

IRA FLATOW: A ton.

IKENNA NLEBEDIM: A ton per batch of electronic waste.

IRA FLATOW: Wow.

IKENNA NLEBEDIM: So if we are able to do 4 batches a day, then that’s about 4 tons a day. So scalability, I think that’s easier. How do we compete with mining? I don’t think the goal here is to compete with mining. I think it’s to augment in terms of resource sustainability.

So from that perspective, when we recover these materials, we need to think about the ways to make them economically feasible. And part of that is what we call co-production, which means when I am recovering the rare-earth, I shouldn’t think that that’s where the profit should come only. We should be able to recover value from other components of the electronic waste. So that’s one of the ways to help with sustainability.

IRA FLATOW: If you get to scale and it gets to be a larger scale, how would you collect all these hard drives? How would you get them? How would that stream reach you?

IKENNA NLEBEDIM: Hard drive is one of the things that are easiest to collect.

IRA FLATOW: Easy?

IKENNA NLEBEDIM: Except the ones that you might have in your closet.

IRA FLATOW: You haven’t seen my closet.

[LAUGHTER]

IKENNA NLEBEDIM: So most of the hard drives are used in data centers. So when you save something in the cloud, it’s actually not in the cloud. It’s in a hard drive somewhere.

IRA FLATOW: Big hard drive.

IKENNA NLEBEDIM: And so they are concentrated. And so when they reach end of life, they are easily collected from that same place. So those are easier than cell phones and so on.

IRA FLATOW: And there are getting to be more and more data centers, aren’t there? Yes, over here.

AUDIENCE: I understand the process of wanting to save the rare-earth particles in there, but what about the– is there any hazardous materials that come out of your process that you have to deal with afterwards? Because of my career, I found that’s the most difficult part at the end, is what you end up making from the process.

IKENNA NLEBEDIM: Thank you. So I think the easiest way to answer that question is to tell you the name of our technology, “acid-free dissolution.” We use no acid in dissolving these rare-earths.

IRA FLATOW: No acid? No acid is going to leach into the soil or into the rivers?

IKENNA NLEBEDIM: So when we dissolve rare-earths, we do it acid-free. And that’s what sets us apart from any other group in the world. And that’s why no other group can do it selectively. So because we do it acid-free, it also means that we eliminate the hazards that are associated with this process, as well as we can make sure that our waste is also not environmentally pollutant. So the process is designed with that in mind.

IRA FLATOW: So let me go to this. We have a few more questions. Yes.

AUDIENCE: How is this going to affect the future?

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IRA FLATOW: Simple question.

IKENNA NLEBEDIM: And a very important one.

IRA FLATOW: And let me add to that. How much will it reduce your need to mine more of those elements?

IKENNA NLEBEDIM: OK. I would say that recycling is one of the solutions. It is not going to eliminate mining. Mining has its own consequences. You said that earlier. So it depends on when these materials reach end of their life. So if you take hard drives for an example, it is possible that by 2040, we should be getting nearly about maybe 20 million tons of rare-earth from recycled product.

But that depends on our efficiency. It depends on if we can collect everything. So multiple factors there. So it will help our future, especially if we don’t take electronic waste that contain things that might not be helpful for our health, and put them back into the landfill.

IRA FLATOW: All right, Dennis, let’s go check out how our recycling is going here.

DENIS PRODIUS: Yeah. So everyone remembering from what we started, yeah? So concentration of magnets is really small, but you can see some red surface. So it’s where the magnet actually starts to react. And yeah, it takes some time because it’s really diluted. So we did yesterday at 11:00 morning just to avoid a situation when it’s not working. And you can see how it looks today. You see some stuff.

So what I will do, I would like to recover rare-earths right now, live.

IRA FLATOW: You’re going to recover?

DENIS PRODIUS: Recover rare-earths with you.

IRA FLATOW: Right now?

DENIS PRODIUS: Right now.

IRA FLATOW: OK.

DENIS PRODIUS: Yeah, why not?

IRA FLATOW: Eyes over there.

DENIS PRODIUS: OK. So we will take a little bit of this solution. So most dangerous stage of this show.

IRA FLATOW: Everybody got their goggles on? OK.

DENIS PRODIUS: We have some magic oxalate-containing solutions. One, two. And I’ll just add them. Are you ready?

[LAUGHTER]

OK.

[APPLAUSE]

One more. A little bit. So now you see how in the bottom formed some product which is containing rare-earths. And we’ll put it together here. Here’s solution, which we really consider like a wastewater. But here are rare-earths.

IRA FLATOW: Oh, look at the bottom.

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DENIS PRODIUS: It’s done.

IRA FLATOW: Denis, thank you very much for being part of this. Denis Prodius, Scientists at the Critical Materials Institute at Ames National Laboratory. And Ikenna Nlebedim, thank you for taking time to be with us today. Also a Materials Scientist at the Critical Materials institute at Ames National Laboratory.

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