Sciencemadness Discussion Board - Simple Americium 241 Experiments?

Simple Americium 241 Experiments?

ssdd - 3-8-2007 at 07:40

Now being Americium 241 is so easy to obtain I was wondering if any interesting experiments could be done with the material. I assume that most things that could be done would be fairly safe being Am 241 doesn't release all that much gamma.

Just one of those things tat popped up in my head, let me know if you have anything and I'll share what I can find.

-ssdd

YT2095 - 3-8-2007 at 07:56

there really isn`t much you can do with Am241 beyond calibration of instruments, they come with a nice metal stamped plate that states the Bequerels (DPS).

if you can find a sensitive enough OP AMP (FET based), you may be able to rig up a crude smoke detector?

Xenoid - 3-8-2007 at 13:15

Although not strictly a "chemical experiment", you could build a simple cloud chamber, using dry ice and alcohol, and observe the alpha particle tracks.

There are numerous websites describing this, try here for example;

http://w4.lns.cornell.edu/~adf4/cloud.html

Xenoid

[Edited on 3-8-2007 by Xenoid]

ssdd - 3-8-2007 at 14:16

So searching around it seems the most I can do is play with the radioactive properties of the metal. Thats a bit disappointing, one would think there has to be something with oxidation states or something or some crazy compounds that could be produced.

I'll keep looking...
thanks for input thus far

-ssdd

12AX7 - 3-8-2007 at 14:55

A microcurie is not much metal. In fact, it's an excellent exercise to show just how much it is, and to calculate how much is left in so-and-so many years.

Tim

Nick F - 3-8-2007 at 15:26

Yeah, you'll have about 0.25 ug, max.

pantone159 - 3-8-2007 at 17:16

Making solutions of alpha emitters is also a good way to manage to ingest some, which is quite hazardous. Am-241 does emit a respectable amount of gamma radiation as well, it is very minor overall for the small amounts used in smoke detectors (1 uCi) but only because that is such a small amount.

JohnWW - 3-8-2007 at 20:02

I suppose you could get the Am-241 out of an older-type smoke detector, - but be careful handling it, because actinide elements like Am are extremely chemically toxic, a result of their high reactivity and high atomic weights, and that is not counting their added radioactive toxicity (although the latter is very low for Th-232 and depleted U-238). I think they make the stuff by bombarding Pu-239 (refined from spent enriched-uranium nuclear power plant fuel rods, primarily for further power generation and bomb-making) with deuterons.

Small amounts of Am-241 may be in the spent fuel rods themselves, as the result of excess absorption (more than one neutron) of the neutron flux from fissioning U-235 by the U-238, along with other relatively long-lived isotopes heavier than mass number 239, e.g. Pu-240, Pu-242, Pu-244, Am-243, Cm-244, etc..

[Edited on 5-8-07 by JohnWW]

I am a fish - 4-8-2007 at 04:51

It is possible to perform chemical reactions with americium if you use a radiation detector to see where the americium is.

For example, you could prepare a solution of CuCl2 containing trace amounts of AmCl3. Adding an excess of NaCO3 (aq) will cause both Am2(CO3)2 and CuCO3 to precipitate out. This would be notiable after seperation, as the precipitate will be radioactive, whereas the solute won't be.

In the above proposal, the CuCl2 is essentially a bulking agent. It allows a noticeable precipitate to form (which will have the americium embedded within it), rather than the miniscule precipitate that would form if pure AmCl3 was used. (Naturally, a vast number of different chemicals could be used in its place.)

Of course, getting the americium out is an experiment in itself. According to this website, the sources are fabricated as follows:

Quote:

The process begins with the compound AmO2, an oxide of Am-241. This substance is thoroughly mixed with gold, shaped into a briquette, and fused by pressure and heat at over 1470°F (800°C). A backing of silver and a front covering of gold or gold alloy are applied to the briquette and sealed by hot forging. The briquette is then processed through several stages of cold rolling to achieve the desired thickness and levels of radiation emission

A possible means of processing is as follows:

(Edit: Revised in light of document posted by "not important")

1. Dissolve the gold foil assembly in aqua regia.
2. Add CuCl2 as a bulking agent.
3. Boil off all the residual acid and continue to heat the resulting solid strongly. This will reduce the gold and silver to their elemental forms, and decompose any nitrates to the corresponding oxides. This will presumably leave a mixture of oxides and chlorides of americium and copper.
4. Dissolve the solid in hydrochloric acid, and filter to remove the gold and silver.
5. Boil away the acid to yield AmCl3 bulked out with CuCl2

(It should be noticed that Am4+ (aq) is reduced to Am3+ by reaction with water.)

[Edited on 4-8-2007 by I am a fish]

Sauron - 4-8-2007 at 05:02

Obviously you have never heard of the hot particle hypothesis.

Don't muck around with alpha emitters, they can hurt you.

not_important - 4-8-2007 at 05:44

It's a fairly poor quality scan, but it does have some information.

Tracer level starts on page 15.

Heed Sauron's advice, do not season your food with it.

[Edited on 4-8-2007 by not_important]

Attachment: the_radiochemistry_of_americium_and_curium.pdf (2.4MB)
This file has been downloaded 1009 times

YT2095 - 4-8-2007 at 05:50

there isn`t enough evidence to support this claim, in fact what little evidence there was, has since been refuted several times over.

I`ll grant you, you shouldn`t Eat the stuff or try and inhale it (choking risk aside) but handled carefully and it presents no extraordinary risk at all.

Antwain - 6-8-2007 at 15:38

When I was considering playing with smoke detectors (I recall that you would get a visible yield, barely, if you could separate the Am) I abandoned the idea because if you inhale (or ingest which is less likely IMO) you will be at risk of cancer for what the next 50 years or so. Decay for decay, alpha emmiters are the WORST thing you can get into your body, the alpha can destroy a LOT before it stops, since it only needs to impart a few eV to something chemical to complete bugger the bonding, compared to a gamma which will probably only interact with one nucleus.

Outside the body, sure it wont make it past the dead cells, but I would be really careful.

ssdd - 6-8-2007 at 18:14

Yea it seems mildly unsafe *sarcasm*, I was just wondering if there would be any interesting reactions with oxidation states or something, probably nothing I'll ever try. But I must admit it is an amazingly interesting material, and alpha radiation has some fun consequences. I had plans to build a cloud chamber in place, so I guess I'll follow through with them.

Thanks all
-ssdd

Nick F - 7-8-2007 at 06:03

A cloud chamber will be totally mucked up by 37 kBq. Unless all you really want to see is a cloud of vapour, and not particle tracks...
Use something much less active. Maybe a piece of thread from a Th-based lantern mantle, or something like that.

kclo4 - 11-8-2007 at 21:51

Alpha particals + Beryllium = Neutrons + Carbon (i think)

If you could get enough, it would be neat to get fine mix of berrylium oxide, and Am 241 oxide it would make a lot of neutrons i bet... and then you die

Protactinium - 27-9-2007 at 09:48

If you had some Be and enough Am you could have a nice little nuetron source maybe. Like 12AX7 had said one microcurie is not much metal at all, and 0.25 ug would be about what you would get if it was 1 uCi (0.29 ug if it was freshly prepared, theoretically).

Antwain - 27-9-2007 at 10:16

Also, crystalline Be reflects neutrons (so well that *apparently* it is used to decrease critical mass in a-bombs) So it would need to be thin as all hell. And if the alphas and neutrons don't get you then the working with the Be will

(nasty stuff that Be)

12AX7 - 27-9-2007 at 11:15

Isn't it the case that neutron sources are usually a powdered combination of Be and an alpha source? (My college's neutron howitzer has a few hundred grams (3Ci) of plutonium in it. I don't remember which isotope.) Powdered Be is the nastyshit, another good reason to leave them to the pro's.

Tim

Protactinium - 28-9-2007 at 23:32

I would say it depends on the materials your using, remember each isotope has a different specific activity per gram which is usually dependent (per se) on the half life and the other radiation being given off by the same isotope. Am241 has seven different energies just from the alpha radiation and those engergies travel at different velocities which of course makes it more complicated for the fabrication of the beryllium.

Antwain - 29-9-2007 at 23:21

I imagine you could make a neutron source by mixing powered Be with an alpha source, but much of the neutrons would be bounced back and combine with your alpha source/ decay products. I think the best way (if you have a linear accelerator) is to bombard a thin Be target with alpha particles.

Jdurg - 4-10-2007 at 17:44

Yeah, it's actually much more difficult to produce neutrons en masse than a lot of people seem to believe. Simply having Be and an alpha emitter, or Al and an alpha emitter in close proximity isn't going to generate a bunch of neutrons. You need to have them VERY intimately mixed for the neutron emission to become high.

Also, alpha emitters are the safest EXTERNAL radiation sources there is. Their radiation can be stopped by a few inches of air, and they simply are not able to penetrate the layer of dead skin cells, or clothes, on your body. INTERNALLY, however, they are the most vicious of radioactive substances and can cause some serious damage since the particles are so large.

JohnWW - 5-10-2007 at 15:42

Quote:

Originally posted by Antwain
Also, crystalline Be reflects neutrons (so well that *apparently* it is used to decrease critical mass in a-bombs).So it would need to be thin as all hell. And if the alphas and neutrons don't get you then the working with the Be will

(nasty stuff that Be)

Nasty stuff? Rather like Al, which it chemically resembles, Be is "nasty" if ingested as compounds (which require chelation therapy to get rid of) or inhaled as finely divided dust (berylliosis). But otherwise, it is a useful very light and largely atmospheric corrosion resistant construction metal, for use where Al is too soft and heavy, and Mg too reactive and also too soft; - but, Be being a much rarer element and found in extractable amounts only in rare minerals like beryl in Brazil, it is very expensive. That is why it was used as the re-entry heat-shield on the Apollo spacecraft.

JohnWW - 5-10-2007 at 15:46

Quote:

Originally posted by Jdurg
Also, alpha emitters are the safest EXTERNAL radiation sources there is. Their radiation can be stopped by a few inches of air, and they simply are not able to penetrate the layer of dead skin cells, or clothes, on your body. INTERNALLY, however, they are the most vicious of radioactive substances and can cause some serious damage since the particles are so large.

That is why Putin had the KGB murder Alex Litvenenko in London last year by inducing him to drink tea wich was laced with a conpound of Po-210, a relatively short-lived intense emitter of high-energy alpha particles. It would not have killed him if they had simply dusted it on his skin, or got him to put an article containing it in his pocket.

Xenoid - 5-10-2007 at 16:15

Quote:

Originally posted by JohnWW
That is why it was used as the re-entry heat-shield on the Apollo spacecraft.

A bit off topic, but!

As a geology student in the late 60's I had the opportunity to visit a beryl mine in South Australia, in semi-desert, somewhere NE of Adelaide. It was privately owned and operated by an old woman. The "mine" consisted of a large hole in the ground and a bulldozer/digger, although I think it had closed a few years earlier. We had lunch in the lady's house, which was surrounded by a "garden" of different sized feldspar and beryl crystals sticking up out of the sand. She showed us a plaque from NASA which was proudly displayed on a wall and which commemorated the fact that she had contributed to the Apollo moon missions. Beryllium from her mine was used in the spacecraft.

EDIT: Actually it might have been the early 70's, can't remember. It all passed so quickly in a haze of beer, sex, drugs and rock 'n roll, not necessarily in that order!

Regards, Xenoid

[Edited on 5-10-2007 by Xenoid]