Sciencemadness Discussion Board

Uranium Ore -> Uranium Oxide & the Metal

kclo4 - 24-9-2006 at 20:30

Okay, well it sounds simple.. (i think)

Well, this is just my made up way of extraction Uranium, tell me what's wrong with it I am sure there is lots! :)

First, crush up the rock nice and fine. And then add Hydrochloric acid (they always say sulfuric acid, but I don't see why HCl wont work, do you)? and mix, stir and let it sit for a week or more, and then filter off the acid solution.

Take the acid solution, and distill off the remaining acid, save it for the next time you extract some more uranium.
After the Uranium chloride solution is concentrated also being "low" in acid >20%, the azetrope of HCl/H2O?
Now, add Sodium Carbonate and let the Uranium carbonate fall out of the solution. Once neutral, filter out the Uranium Carbonate, and let dry
Heat the Carbonate leaving UO2?

Well, personally this sounds like a crappy way, does any body have any ideas on how to get high yield, for cheap?

thanxs in advance

12AX7 - 24-9-2006 at 20:49

Just how pure is your ore? 100%? Sounds like a good mineral specimen to me, much more so than some crappy piece of ore to digest.

Recrystallization is needed for sure. You'll have lots of iron and silica and alumina, being that's what the Earth is mostly made from. I recall something about uranium crystallizing with barium chloride.

I wonder if silicates will even break down, without exposing most of the surface (i.e. micron range powder). Seems like a hydrofluoric thing to me...(!)

Tim

not_important - 24-9-2006 at 23:19

The process is going to depend on which ore you have. Crushing the ore means taking it to flour-like fineness.

Sulfuric is sometimes used because the ore/acid mix is heated to beak down some of the minerals, and you can heat H2SO4 a lot hotter than HCl. In other case what is being done is a slow leaching, where the non-volatility of H2SO4 means it is going to stick around for weeks while HCl would have been long gone; doing your extraction in a closed container will avoid that - but note you still need a pressure release if there are carbonates.

Often the ore extract is treated with oxidisers to convert from U(IV) to U(VI), this could release chlorine if HCl was used.

Purification is going to depend on what other elements are in the ore. Silicon as silicates, aluminium, the alkali and alkaline earth metals are not a problem. But phospates, vanadium, copper, the rare earths, titanium, iron, and manganese all show up in ores. (manganese show up a lot of places, and you can't get away from iron) The purification route you use is going to depend on what else is in the ore.

Sometimes the uranium is ppt from solution using ammonia, gas or strong solution, to give (NH4)2U2O7 ( "yellowcake", or one of the yellowcakes )

ethan_c - 25-9-2006 at 13:28

Quote:
Originally posted by 12AX7
I recall something about uranium crystallizing with barium chloride.


Uranium needs to be coprecipitated with barium sulfate, IIRC. I am also under the impression that finely divided uranium will not only react with air, but water as well.
Quote:
I wonder if silicates will even break down, without exposing most of the surface (i.e. micron range powder). Seems like a hydrofluoric thing to me...(!)


Hydrofluoric acid would be necessary unless the ore could be powdered very finely. Or, alternately, a mix of sodium fluoride and sulfuric acid if one is using the sulfuric to digest the ore anyways.

Jdurg - 25-9-2006 at 17:52

In addition, decay products such as thorium, radium, lead, and various other materials will be present in the ore and generally make the process "not too much fun".

not_important - 25-9-2006 at 21:14

Quote:
Originally posted by Jdurg
In addition, decay products such as thorium, radium, lead, and various other materials will be present in the ore and generally make the process "not too much fun".


The uranium to radium ratio in typical uranium ores is around 3 x 10^6 to 1, meaning if you have a tonne or ore, you have about a tenth of a gram of radium, maybe.

The other stuff in the ore is the purpose of the processing done. Thorium is enough different chemically than uranium that it isn't too bad to separate, and it is only present in a fraction of a percent at best. Lead is quite different, simply using H2SO4 and diluting correctly will ppt most of the lead as the sulfate while uranium forms several sulfate complexes.
Quote:
Originally posted by ethan_c
Quote:
Originally posted by 12AX7
I recall something about uranium crystallizing with barium chloride.


Uranium needs to be coprecipitated with barium sulfate, IIRC. I am also under the impression that finely divided uranium will not only react with air, but water as well.



It's radium that is co-precipitated with barium. As I noted about, at 1 part in 3 million or uranium there's not a lot of radium around. Barium is above radium in the periodic table, they follow each other around.

Uranium metal is somewhat reactive, but there's a ways to go from ore to being ready to make the metal, get to that stage first.

One way to get to bulk uranium metal is to use the van Arkel and de Boer method, which gives pretty crystalline bars of metal.
Quote:

Quote:
I wonder if silicates will even break down, without exposing most of the surface (i.e. micron range powder). Seems like a hydrofluoric thing to me...(!)


Hydrofluoric acid would be necessary unless the ore could be powdered very finely. Or, alternately, a mix of sodium fluoride and sulfuric acid if one is using the sulfuric to digest the ore anyways.


Finely powdering seems to work for industrial production, you might need to ball mill the ore. Uranium does not seem to really lock itself into silicate structures from what the old books on uranium mining say, the acid extraction process pulls much of it out of the ore.

Thus messing around with HF or acid fluorides isn't likely to be needed.

ethan_c - 25-9-2006 at 21:29

Quote:
Originally posted by not_important
One way to get to bulk uranium metal is to use the van Arkel and de Boer method, which gives pretty crystalline bars of metal.


Holy shit. I would give my left nut for a bad of Arkel-de Boer uranium, in all seriousness.

JohnWW - 26-9-2006 at 15:56

What are you going to do next, after extracting the U as the metal (which I think could be done electrolytically)? Convert it to UF6 with F2 gas (HAZARDOUS), and then use centriguges or diffusion to enrich it in U-235 for use in nuclear fuel rods or bombs?

not_important - 26-9-2006 at 16:16

I don't think uranium can be electrolytically produced, it is pretty reactive. The normal method of making metallic uranium is through the reduction of the tetrafluoride with magnersium or calcium.

The refining process is something like
Dissolve in H2SO4
Extract with tertiary amines in kerosene.
Back extract using aqueous ammonium sulfate
Precipitate ammonium diuranate using ammonia.
Heat that to make U3O8
(that is then shipped to refining plants)
Dissolve the U3O8 in nitric acid
Extract with tributyl phosphate in kerosene
Back extract using dilute nitric acid
Concentrate that solution to get uranyl nitrate
Heat that to get UO3
Reduce the UO3 with hydrogen to get UO2
React UO2 with HF to get UF4

For the non-enriched metal the UF4 is reduced with an active metal.
For gaseous diffusion the UF4 is converted to UF6 using F2.

Edit - note that the concentration of urnium as U3O8 in ores runs from about a half percent to maybe 30% in very rich ores. If you're starting with the sandstone type ores, 10 Kg will net you maybe 25 gr of uranium metal; better if you have one of the richer ores.



[Edited on 27-9-2006 by not_important]

kclo4 - 26-9-2006 at 20:08

I have not got my ore yet, but I will soon. And lots of it for cheap!
I think* it is going to be pitchblend, so mosty UO2

Anyway I think I am going to have a VERY HARD time making the Ore into a powder, any suggestions?

Also, after I get the chloride salt of the uranium and friends, will kerosene extract a good amount of it? Like 98% of the uranium in solution, or perhaps more?

And just a thought, once the Uranium chloride was in the solvent, could I simply add zinc then? Sense there really wouldn't be much/any water?

Well, I guess there would be water in it, so it wouldn't work would it?

ethan_c - 26-9-2006 at 20:38

Quote:
Originally posted by kclo4
Anyway I think I am going to have a VERY HARD time making the Ore into a powder, any suggestions?


Sledgehammer (contained in some sort of sack or bag) ––> large Ball Mill (with chrome steel media)

not_important - 26-9-2006 at 21:30

Quote:
Originally posted by kclo4
I have not got my ore yet, but I will soon. And lots of it for cheap!
I think* it is going to be pitchblend, so mosty UO2

Anyway I think I am going to have a VERY HARD time making the Ore into a powder, any suggestions?

Also, after I get the chloride salt of the uranium and friends, will kerosene extract a good amount of it? Like 98% of the uranium in solution, or perhaps more?

And just a thought, once the Uranium chloride was in the solvent, could I simply add zinc then? Sense there really wouldn't be much/any water?

Well, I guess there would be water in it, so it wouldn't work would it?


As ethan said, hammer to get large pieces broken up, a ball bill to finish. Something useful for the range between hammer and mill is a morter made from a soild rod of metal and a surrounding container, such as a piece of capped pipe whose inside diameter is slightly greater than the diameter of the rod. Put some same id, drop the rod on top, hit it with a hammer a few times.

When reducing rocks to dust, sieves are handy. These don't need to be the expensive cailbrated sizes type, just metal or plastic screen of several mesh sizes, stretched over bottomless cans or pieces of plastic pipe. Makes it easy to separate the bigger lumps that need more work from the stuff that is ready for the next stage.

The extraction process depends on several things. One is the presence the the tertiary amine or tributyl-phosphate; without those not much is likely to go into the kerosene.

The second may be sulfate. From what I've read, it is a sulfate complex that gets extracted, I've no idea if the chlorides work. Note that there often is an oxidation step to get the uranium into the 6+ state, as UO2(2+). A chloride solution might have problems with this step, I know that UOcCl2 is not very stable.

However, there is a chloride base process used on monazite:

http://www.npcil.nic.in/nupower_vol18_2_3/pg081-83.pdf


Zinc is not going to convert uranium salts into the metal, from what I remember of the respective theromdynamics. The processes I know of are the reaction of UF4 with Ca or Mg, electrolysis of UF4 or KUF5 in molten CaCl2+NaCl, and the aforementioned Arkel-de Boer process usign the iodide. All of these are anhydrous processes.

Do note that uranium is chemically toxic, it is a 'heavy metal' and can hurt you in ways other than making you glow in the dark; UO2Cl2 is flagged as being rather toxic for some reason.

Edit - all the soluble UO2(2+) salts are considered very toxic.

For more details, you'll likely need to track down documentation on uranium metallurgy.

A side note, I'd rather have a sack of monazite than one of some uranium ore, as monazite has both thorium and uranium, plus rare eather elements. But I've never seen any of it for same except as very small samples, or railcar loads, which the storeroom is too full to hold.


[Edited on 27-9-2006 by not_important]

Magpie - 26-9-2006 at 22:02

Similarly I am also doing a size reduction on some quartz mineral. This is in preparation for a fire assay for gold. I only need about 30g for each assay but have found that it's pretty hard to turn into a powder. I first broke up a piece using an old shirt and a hammer to pieces no bigger that a pea. Then I used a small iron mortar & pestle to grind these pea sized pieces to a powder passing a 24 mesh screen. I need it to pass a 170 mesh screen so am planning on buying a small ball mill (with chrome plated steel balls) from United Nuclear. United Nuclear also provides instructions for making one yourself.

12AX7 - 26-9-2006 at 22:26

When I want to grind something, I smash it down to about 4-8 mesh with a hammer and then grind it with the flat top of the hammer (I happen to use a rock hammer which has a long flat curved top surface, square face and flat chisel back side). This is against smooth concrete or a good solid steel surface (I have a nice block of cast iron, unfortunately it gets rusty from grinding down various salts..). Not especially fun, especially for hard materials (I won't relate my pleasure of grinding grog (fired clay) down to size), and time-consuming for fine grades, but it's something.

Tim

Jdurg - 28-9-2006 at 16:58

Also remember that while externally the radiation from uranium really isn't anything to worry about, internally it is VERY nasty stuff. Make sure you do not inhale ANY of the powder. Alpha particles in your lungs and nasal passages is a surefire way to get yourself cancer. So try and keep everything isolated so the powdered ore doesn't get suspended in the air and also make sure you clean up everything very thoroughly afterward.

ethan_c - 28-9-2006 at 17:12

Quote:
Originally posted by Jdurg
Also remember that while externally the radiation from uranium really isn't anything to worry about, internally it is VERY nasty stuff. Make sure you do not inhale ANY of the powder. Alpha particles in your lungs and nasal passages is a surefire way to get yourself cancer. So try and keep everything isolated so the powdered ore doesn't get suspended in the air and also make sure you clean up everything very thoroughly afterward.


(Respirator)

Zinc - 5-11-2006 at 12:33

At http://www.roguesci.org/megalomania/explo/perchlorates.html I have read that uranium trioxide can be bought at a hardware store.
Is that true?

Waffles - 5-11-2006 at 22:21

Quote:
Originally posted by Zinc
At http://www.roguesci.org/megalomania/explo/perchlorates.html I have read that uranium trioxide can be bought at a hardware store.
Is that true?


No.

PLEASE correct me if I am wrong. :):)

not_important - 5-11-2006 at 23:41

Not any hardware store that I've been in. While at one time pottery supply places sold uranium oxide, that time is past.

You could always enlist to go to Iraq. Between the DU munitions and the supply of under-seal yellow cake that the US forces failed to guard and which was looted for the barrels it was in, Iraq has a lot of uranium about.

unionised - 6-11-2006 at 11:51

Sorry, but I can't think of any reason why a hardware store would stock it unless it's accidentally present in something else. There are traces of uranium in some phosphate fertilisers for example- easy enough to spot with a geiger but hardly a decent supply.

The_Davster - 6-11-2006 at 14:58

Sounthern Alberta had a 'Uranium rush' of sorts start last summer. I have been meaning to find an excuse to go over there and do a little prospecting. Or if you are near new mexico I suppose you could go there if that is closer to you.