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Researchers produce nearly-pure rare earth concentrates from coal

uknow.uky.edu

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Re: Researchers produce nearly-pure rare earth concentrates from coal

#21

Post by maxerickson »

mchannon wrote: post #4

Amazing how nobody who reports on this puts forward any numbers. This Appalachian coal is said to have over 300ppm of rare earth oxides in it. That means for every ton of coal, we're talking about 300g of material. Compare conventional rare earth ores, where for every ton, we're talking about 90kg (Mountain Pass). It's nice and all that these things are in coal, but thermal coal's already on its way out, Appalachian…

One of the plants they are locating the pilot at can apparently process 950 tons of coal an hour:

https://www.tecoenergy.com/news/article/index.cfm?article=20...

So if you process it all and get high extraction, a couple million Kg of rare earths a year.

(I edited the last paragraph after spotting that I missed a factor in my initial math)

Re: Researchers produce nearly-pure rare earth concentrates from coal

#22

Post by mchannon »

wrycoder wrote: post #18

I’m wondering why rare earths end up in coal in the first place.

Coal (at least most of the time) comes from decaying plants.

Before the plants decayed, they pulled up all manner of minerals from soil. Rare earths behave similarly to iron, so if a plant can uptake iron from its soil (it can) then so can it uptake rare earths.

There are numerous instances of field reclamation from mercury contamination specifically by use of plants to leach the mercury from the soil, then harvest, burn, and safely dispose of the mercury concentrate.

https://www.fastcompany.com/3033295/cleaning-up-polluting-mi...

Same story as this except the latter occurs in a human lifetime, and we want the mercury out of the soil for fundamentally different reasons.

Re: Researchers produce nearly-pure rare earth concentrates from coal

#23

Post by dpark »

pjc50 wrote: post #13
reacweb wrote: post #3

Earlier quoted context omitted.

IMHO, the future is solar energy and storage. If coal wants to remain significant in long term, it has to find arguments.

Coal is not conscious, it cannot want. The coal industry may want, but like everyone else they're not guaranteed relevance in the long term. Going out of business is capitalism's way of saying your product is no longer required.

> Coal is not conscious, it cannot want.

And capitalism has no speech capacity.

If you’re going to be pedantic to the point of abrasiveness, at least don’t use the same shorthand you are criticizing.

Re: Researchers produce nearly-pure rare earth concentrates from coal

#24

Post by ClintFix »

I was an engineer at a company attempting to extract rare earth metals from fly ash using a solvent method (supercritical CO2). Similar to how caffeine is removed from coffee.

There aren’t a lot of rare earths in coal/fly ash but even modest coal plants produce tons of fly ash daily.

Re: Researchers produce nearly-pure rare earth concentrates from coal

#25

Post by d0lph »

vanderZwan wrote: post #16
pjc50 wrote: post #13

Earlier quoted context omitted.

Coal is not conscious, it cannot want. The coal industry may want, but like everyone else they're not guaranteed relevance in the long term. Going out of business is capitalism's way of saying your product is no longer required.

> Coal is not conscious, it cannot want. This is pedantic to the point of wilfully not wanting to understand that the coal industry is implied with that statement. But if we're going down the pedantic route: > Going out of business is capitalism's way of saying your product is no longer required. Demand and need are correlated, but not the same. Capitalism works with the former, and also has an entire industry devote…

Capitalism exclusively aligns with societal needs, if society does not need or want something we don't buy it, the business evolves or goes bankrupt. Capitalism is not just amoral, but also is democratic in nature.

Re: Researchers produce nearly-pure rare earth concentrates from coal

#26

Post by John_KZ »

mchannon wrote: post #4

Amazing how nobody who reports on this puts forward any numbers. This Appalachian coal is said to have over 300ppm of rare earth oxides in it. That means for every ton of coal, we're talking about 300g of material. Compare conventional rare earth ores, where for every ton, we're talking about 90kg (Mountain Pass). It's nice and all that these things are in coal, but thermal coal's already on its way out, Appalachian…

The US already produces and consumes 1 billion metric tons of coal per year. Numbers in Europe are similar. Also all this coal is already cleaned and crushed. That's a lot of mass, even at the low yields, and it's essentially "free" ore.

The real limiting factors are throughput and cost of ore processing. If the process can be done economically at the rate of production, it will be implemented. Even if it barely brakes even in terms of finances, it also helps with A) stopping rare earth metals from going airborne (which is a health hazard sometimes) and B) Creating a strategic backup source of rare earth metals and C) Preventing further environmental damage from additional mining for rare earth metals elsewhere.

Re: Researchers produce nearly-pure rare earth concentrates from coal

#27

Post by John_KZ »

ClintFix wrote: post #24

I was an engineer at a company attempting to extract rare earth metals from fly ash using a solvent method (supercritical CO2). Similar to how caffeine is removed from coffee. There aren’t a lot of rare earths in coal/fly ash but even modest coal plants produce tons of fly ash daily.

Also fly ash is a pain in the ass to get rid off. I've heard about companies re-using it in concrete products and other construction materials. Even if the value produced is low, any profit is better than dealing with the cost of safely disposing it.

Re: Researchers produce nearly-pure rare earth concentrates from coal

#28

Post by Erlangolem »

John_KZ wrote: post #27
ClintFix wrote: post #24

I was an engineer at a company attempting to extract rare earth metals from fly ash using a solvent method (supercritical CO2). Similar to how caffeine is removed from coffee. There aren’t a lot of rare earths in coal/fly ash but even modest coal plants produce tons of fly ash daily.

Also fly ash is a pain in the ass to get rid off. I've heard about companies re-using it in concrete products and other construction materials. Even if the value produced is low, any profit is better than dealing with the cost of safely disposing it.

Wouldn’t that make the resulting concrete unusually radioactive?

Re: Researchers produce nearly-pure rare earth concentrates from coal

#29

Post by topspin »

Scandium is mentioned as one of the "rare" earth elements readily recovered from coal. I can't speak for the viability of this process, but cheap scandium would be a great outcome. Small amounts of Scandium greatly improves the tensile strength, fatigue behavior and other properties of Aluminum.

Re: Researchers produce nearly-pure rare earth concentrates from coal

#30

Post by logfromblammo »

reacweb wrote: post #3
vanderZwan wrote: post #2

Waiting for someone to tell point out why this process is super-toxic, or prone to ruining the environment in some other fashion, or some other bad news. Also curious if anyone can to weigh in on how this might affect China's (supposed) rare earth monopoly, since I presume that was part of the motivation behind the research. Same thing for the coal industry in general.

IMHO, the future is solar energy and storage. If coal wants to remain significant in long term, it has to find arguments.

I could see an argument for coal used to enrich soil for agriculture, if there were a way to economically remove all the toxic metals from it. Urine and bone meal would round it out.

It could be a carbon source for a new type of terra preta.

It would even be useful for the high-sulfur coals.

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