physics inclination
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possibility of aluminum nanoparticles via acetonitrile and ultrasound
So I've thought of a possible method to make aluminum nanoparticles, which are of course useful in flash powders, which was inspired by this research
article:
http://pubs.acs.org/doi/abs/10.1021/acs.jpcc.6b04054
these researchers found an apparently effective way of making nanoparticles by milling aluminum spheres in an orbital mill, along with acetonitrile
liquid or vapor (they found the vapor was preferable but both worked).
So I did some looking, and it seems that the main important chemical, the solvent acetonitrile, is somewhat viable for amateur production (I even saw
it recommended as a "first project" in some other thread lol). But the ball mill they used seemed fairly expensive, so I wonder if the process could
work with ultrasonic cleaning machines instead--these are very inexpensive, I even saw some models for around $30-40 so even if it breaks by the
solvent then not too much money was lost. And I actually think the ultrasonic cleaners may be able to handle it, because they're designed to handle
some other solvents so perhaps acetonitrile would be fine...although I'm not totally sure.
Anyways, what do you think about this method? plausible, questionable, or unlikely?
Aside from that method, I have also found a list of other various methods for chemically-related production of aluminum nanoparticles. I think they're
a bit more difficult, but I could be wrong and maybe there's an easier more amateur-viable route:
http://www.orientjchem.org/vol30no4/a-review-of-methods-for-...
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PHILOU Zrealone
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Possible via ultrasounds...
Sonochemistry uses a Titanium horn and apparently with this into a halogenated solvent where Mg ribons are dispersed (avoiding air and water) one is
able to make Grignard's reaction without ether (what is usually required to allow for a complex stabilisation)
==> The Mg surface becomes picked by cavitations bubbles and get to an impressive active surface...to get cavitations bubbles the solvent must be
volatile to some extend what fits with the properties of acetonitrile.
No doubt the Mg will become pyrophoric and very reactive towards water...so will Aluminium.
I don't understand why the nano Al from acetonitrile is not pyrophoric just like the one made from Ar and N2...maybe has it a lower particle size or a
lower specific surface?
Unless the acetonitrile sticks somehow to the Al via its C#N sp bond and coat it?
I also had the idea to make nano Al via ultrasounds but into oïl and then washing with hexane/pentane or cyclohexane/cyclopentane.
I have dendritic nano-Al powder made from Al wire explosion into cold Ar and then brought back to normal atmosphere by slowly allowing cold air to
enter the reactor...this minimizes the protective oxyd/nitride layer and provides more active metal per unit volume.
That Al powder burns fiercely into the open from the spark of a lighter...NH4NO3/Al mix made with it was crackling composition...thermite Fe2O3/Al was
very fast (not exploding)...the Al burned with two phase a first one orange-yellow then a second one very bright and silvery-white.
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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physics inclination
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Ok I found how to link the full article here.
And regarding milling aluminum with regular oils, it says that it just polishes the surface of the grinding balls. It also says the researchers coated
the resulting nanoparticles with oleic acid after milling, I guess to prevent oxide layer and to passivate the aluminum in a more combusible surface
material (that is, hydrocarbons). I mean, so rather than the oxide layer which inhibits combustion, it is a more combustion-friendly surface I think.
Attachment: aluminum nanoparticle production by acetonitrile assisted milling.pdf (2.7MB)
This file has been downloaded 446 times
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