Sciencemadness Discussion Board

Uranium Chemistry, A Quora Responce

SimpleChemist-238 - 19-1-2015 at 07:38

Uranium gets a bad rap, being widely regarded as exotic and dangerous. As a fellow "amateur chemist" (more recently, career nuclear engineer) experienced with uranium, I would like to challenge this unfairly negative reputation and suggest that you CAN study the "household chemistry" of uranium safely and responsibly without resorting to a poor surrogate. A basic working knowledge of inorganic chemistry is a prerequisite to a satisfying experience; that is true of all chemistry. So be comfortable with stoichiometry, balancing equations, measuring mass and volume, etc. Be comfortable with prevailing standards of chemical hygiene and safety, like wearing gloves and eye protection. The big dangers here are the same mundane ones you'd find in high-school intro chemistry: strong acids and bases, hotplates, flammable solvents. Although a toxic heavy metal, uranium is far more approachable than, say, arsenic or mercury or fluorine chemistry in a residential setting. The keys to good hygiene and responsible use lie in working with small quantities (think about containing the mess if a container were to break or fall over) and controlling waste generation. Buy some microscale glassware. Just be aware that if you work with large (~kg) quantities, or plan to sell or transfer things you make to other people, you are no longer an inconsequential "hobbyist" and will find yourself up against the strictures of your jurisdiction's nuclear regulatory framework, which in the USA is the domain of the Nuclear Regulatory Commission. The NRC defines, and subjects to a general license for use, "small quantities of source material" below 1.5 kg; see 10 CFR 40.22. So if you play around with some introductory uranium chemistry, start small (with a couple grams of material) to avoid the prospect of a soul-crushing run-in with regulators.

How to obtain uranium: You have two choices. First choice is to buy uranium on eBay, where there are regular sellers of compounds like uranyl nitrate and oxide. Depending on your focus, you might be interested to know if your uranium source is "depleted" (low in the U-235 isotope) or "natural" (0.72% U-235). Typically, commercial uranium compounds are made from depleted uranium (cheaply available from the nuclear fuel industry), while those prepared from uranium ore directly are natural. Your second choice is to refine uranium from a concentrated ore specimen. This process is not difficult (see my website link below), but it does generate a lot of waste that can't be put down your drain.
Basic chemical overview: Aqueous uranium chemistry is dominated by the uranyl ion (UO2)2+, with U in the U(VI) oxidation state. This is a brightly-colored, greenish-yellow, UV-fluorescent species. Uranyl compounds are generally soluble in acids, and precipitate as marginally-soluble yellow to orange uranate and diuranate salts with alkalis. Uranium in its lower (IV) oxidation state is sometimes encountered in the form of the dioxide UO2 and the green tetrafluoride, UF4. These compounds are not appreciably water-soluble and in order to dissolve uranium in these forms, it must be oxidized to (VI) with an appropriate reagent. Uranium metal is very hard to prepare in small quantities and you will probably not get an opportunity to buy it in metallic form either.
Suggestions for chemistry of interest: Uranium is unusual chemically in a few respects. Consider its nearly-insoluble peroxide: no other naturally-occurring elements have an insoluble peroxide at acid pH. Uranium forms some commercially-interesting complexes, like the uranyltricarbonate anion (which is soluble in basic solutions, in which most transition metals precipitate) and the uranyl nitrate-tributyl phosphate complex (which forms the basis of liquid-liquid solvent extraction of U and Pu in nuclear fuel reprocessing), and a peroxo complex that is vivid blood-red. You can play with this chemistry at home because the other chemicals needed are ordinary. TBP has to be ordered from a chemical supplier, but you shouldn't be given trouble for it. Uranium offers interesting opportunities for radiochemistry. Prepared uranium--depleted or natural--quickly builds up an equilibrium concentration of U-238 decay daughters Th-234 and Pa-234. These are beta- and gamma-emitting nuclides, whereas the parent U-238 only emits alpha particles. Thus, it is fun to see in any given chemical experiment with uranium if the apparent activity (on a common beta-gamma sensitive Geiger counter) follows the uranium itself or not. Freshly-purified uranium compounds will seem minimally radioactive, but after a couple months Th and Pa are back in the uranium! The waste from re-purifying daughter-contaminated uranium compounds may be left around to decay, and will exhibit the easily-measurable half life about about three weeks due to the Th-234.
My own background: see my blog posts about household uranium chemistry here: http://carlwillis.wordpress.com/...
Dabbling in uranium chemistry is fun for the whole family, educational, and it ain't gonna kill you or the neighborhood as long as common sense prevails.

Below: uranium compounds made by safe and responsible household techniques. See website for details.

Posted by Carol Willis on Quora.com

neptunium - 19-1-2015 at 11:18

very good stuff! some precious info thanks!

bismuthate - 19-1-2015 at 11:20

I just read your blog recently. Great work.
However, I was wondering how one would go about disposing of uranium waste.

P.S. It's a shame there are no uranium ores where I live.

careysub - 19-1-2015 at 17:29

Quote:
I just read your blog recently. Great work.


I don't think the poster is Carl Willis (not Carol Willis).
Quote: Originally posted by bismuthate  
...
P.S. It's a shame there are no uranium ores where I live.


Wait! Where do you live? Uranium ores are more widely distributed than you might suppose.

In addition, you can buy uranium ore. Shannon & Sons Minerals offers 1 kg of German pitchblende (from the former East German Hartenstein, Saxony district) for $155. That should give you enough material for a good work-up.

https://www.shannonsminerals.com/shop/index.php/shannonsmine...

[Edited on 20-1-2015 by careysub]

bismuthate - 19-1-2015 at 17:45

I live in Massachusetts. I can't find any info on uranium ore here.

careysub - 19-1-2015 at 22:07

Quote: Originally posted by bismuthate  
I live in Massachusetts. I can't find any info on uranium ore here.


There are radioactive pegmatites found throughout New England. There is a famous collecting site (Grafton Center) in New Hampshire. Another is Topsham Maine.

SimpleChemist-238 - 20-1-2015 at 17:52

Sorry, this is not my work but a reply from a question I asked to him. I did not want to take credit for is answer but wanted to share it.

j_sum1 - 20-1-2015 at 21:58

Hmmm
All this has gotten me thinking. Bottom line is that I think U chemistry is out of my league at present. I would require better equipment than I have and a good deal more knowledge. And probably some advice. I wouldn't trust myself to read and be confident that I had covered all the gaps. Still, the variety of oxidation states is fascinating.

I would love some depleted metallic uranium for the collection. I would also be interested in collecting some ore samples. I know that Australia has uranium deposits in higher concentrations than anywhere else in the world and exports a significant proportion of the world's fuel supply. A quick search reveals that Queensland, where I live has numerous relatively rich reserves and some of them mined. However, there is nothing notable within 1000km of where I live -- nothing where I could reliably read up on my minerology drive to the right place and pick up a sample off the ground. And of course Queensland has an irrational politically-entrenched fear of all things nuclear and so it would be nigh impossible to obtain any metallic samples locally and probably almost as difficult to find some ore.

So while I realise that uranium is not quite the bogeyman element it is made out to be, there exists quite an assortment of hurdles that would need to be overcome before I could investigate its chemistry.

Tdep - 20-1-2015 at 22:24

I agree with j_sum1, even if you get over the stigma of uranium chemistry, doesn't mean anyone else has. Last time I looked into it there were heavy fines (we're talking 10 years jail time) for mining uranium ore and same would go for attempting its chemistry. And it's something my neighbors would report me, for sure. With all the "report any suspicious behavior to the terrorism hotline and federal police" on the radio all the time here, the real risk with uranium is from the law, no doubt.

It's a shame, because I live in South Australia and if you're looking for a place to find uranium - it's here. Bit of a drive but I love a roadtrip (just not in a police car).

j_sum1 - 20-1-2015 at 23:49

The real irony is that if you were to design from scratch a geography to mine and process radioactive substances and safely store the waste, then you would design exactly what Australia has. Rich reserves. Isolated regions away from populations. Stable geography. Rich in other mineral resources. Low rainfall to minimise leaching. etc.
The truth is that there is political will to dig it up and sell it off shore. But no political will to do anything with it ourselves. Not even to train people on its properties (chemical and other).
If we had our heads screwed on we would have wind farms and solar farms to run banks of centrifuges and sell a value-added product while at the same time and same facility do a whole lot of research and development and train people to effectively manage a range of both green and conventional energy solutions.

Tdep - 21-1-2015 at 00:55

Or even, oh I don't know, actually build our own nuclear power plant?? All this talk about renewables and nothing for nuclear, ever. No political party would even consider bringing it up.

"Buttt wherrrer arreee weee ggoiinngg to putt thhee waassstteee" - every politician.

Well, have you considered theirradiated zone in the middle of the country (wasteland) that's the size of England? Already closed to the public? Where you're only allowed to drive through but can't stop?

Oh nah, probs need that area. For like, more of America's nukes or something.


(Did I just start talking about politics in a chemistry thread? Sorry, yeah I'm pretty into this topic. Depleted uranium chemistry sounds awesome yep back on track)

(Edit 2: sorry, it was Britain with the nukes. Not that i'm really against that and all, it's just that Australians have this view of 'our land is unspoiled, nuclear power would destroy it' when no, there's really just so much wasteland')


[Edited on 21-1-2015 by Tdep]

[Edited on 21-1-2015 by Tdep]

careysub - 21-1-2015 at 12:33

Quote: Originally posted by j_sum1  
...The truth is that there is political will to dig it up and sell it off shore. But no political will to do anything with it ourselves. Not even to train people on its properties (chemical and other).
If we had our heads screwed on we would have wind farms and solar farms to run banks of centrifuges and sell a value-added product while at the same time and same facility do a whole lot of research and development and train people to effectively manage a range of both green and conventional energy solutions.


Australia has developed a unique uranium enrichment process called SILEX (pulsed molecular laser separation) that is nearing commercialization, and does have active solar power development:
http://www.fool.com.au/2013/08/28/silex-systems-expects-grow...

http://newsstore.smh.com.au/apps/previewDocument.ac?docID=GC...

But you have a valid point about the "curse of the raw materials blessing". By and large having abundant supplies of raw materials to sell seems to hold countries back in development, rather than the reverse.

Japan and the Asian Tigers demonstrate that raw materials are not needed for high levels of industrial development, as long as you can buy them from someone.

Jared Diamond, in his book "Collapse" does an excellent job showing that selling raw materials, instead of building up the industries that process them into finished, of semi-finished products, is massively foolish.

It was only in the first phase of the Industrial Revolution that having raw materials locally was important. Without its well located coal and iron deposit, the IR in Great Britain would never have started. Similarly the IR spread to other countries that also had local deposits, and the U.S. in the 19th century was by far the most successful follower along these lines.

But once the second industrial revolution got underway (starting in the 1860s), with more sophisticated products with a high science content (think dyes and electricity), this advantage started quickly disappearing.

Today the U.S. is selling itself short by exporting its lumber in raw form to be processed into high value products in Asia, instead of creating jobs and wealth at home. Australia is doing the same with many of its resources.

neptunium - 21-1-2015 at 14:46

the middle east is doing the same with its oil...

j_sum1 - 21-1-2015 at 16:36

Thanks careysub. Appreciate your info and insights.
I knew that there is one processing plant in the country but had not realised that there was any significant work being done on enrichment.
I guess my beef is that we don't use our resources well. Australia should be a world leader in solar technology. Australia should be a world leader in desert reclamation. (That would do more for CO2 levels than anything else.) Australia should be a world leader in nuclear technologies. And Australia has the mineral resources to develop and produce cutting edge technologies that will be vital in our developing world. I am thinking batteries and exotic materials.
What Australia is good at is exporting resources to China and then complaining about "inferior Chinese crap" that threatens genuine 'Strayyan businesses. And we are very uncomfortable at the thought of Asian cultural and financial imports. All of this is fuelled by irrational fears that are culturally and politically entrenched.

I fear I am derailing this thread with local politics. So, back on topic. There is probably no field of amateur science that is more demonised than radiochemistry. So much so that it is pretty much infeasible to get it off the ground -- at least here. And while I do not yet have the skill set to delve into it, I agree with the OP that it is something worth exploring and not something that should be considered off-limits.