What about this variation of the nitro/Al reaction??

[sparks]

I tried to post this before, but something went wrong.
Anyways, why don't you do it the nitroway n'til the end?
It's easy and troubleless.
It may be a bit more exotermic than expected, but if you live in the northern hemisphere you have lotsa snow to keep it contollable with.
All in all, a very nice and useful reaction.
(just think about where you're putting that mercury waste, otherwise your karma goes to hell, and that we don't want, do we?)

[lab_bitch]

Oops, well I thought that was all... but tonight Mr. Adigk tried aluminum roasting pan aluminum (~4 mil thick) and tried dripping in 90% of the MeNO2 first. Something did not work, because the ketone remained unconverted after 6 hours of stirring in the flask with the aluminum and the nitro, and no methylamine smell was ever detectable. Only ketone smell. Shit! Now he needs to figure out how to maybe salvage that ketone

Did the addition of the MeNO2 cause the aluminum to break down?  Did the aluminum turn dull grey (amalgamated) b/f you added the nitro?  If you don't first let the Hg reduce on the aluminum surface b/f adding other reagents, they will complex with the Hg and prevent amalgamation.  Perhaps you added the nitro too early.

[lab_bitch]

Could the fact that he only used 180mg of HgCl2 with much thicker Al have something to do with it?

With thicker foil, you have less surface area and thus need less HgCl2.  I am pretty sure that adding more HgCl2, changes the reduction potential of the metal, making it less energetically favorable for the aluminum to oxidize.  This slows the rate of reduction.  On the other hand, more HgCl2 increases the rate of reduction of the nitro/ketone b/c it serves as a catalyst.  The reduction will not occur if HgCl2 is not added.  Even if the oxidative coating was removed from the aluminum, it would only react with the solvent.

[lab_bitch]

It may be a bit more exotermic than expected, but if you live in the northern hemisphere you have lotsa snow to keep it contollable with.

Antarctica is in the southern hemisphere, and has more snow than you've ever seen in your life.

[Diggity]

The reduction will not occur if HgCl2 is not added. Even if the oxidative coating was removed from the aluminum, it would only react with the solvent.

Im confused.. why does the "preparation of AL/hg" by Eleusis describe AL being amalgamated, then the Hg containing solvent poured off the al, then non hg containg solvent poured back over, and stored to be used at a later date?

Prepare a ~2% Mercuric (II) Chloride solution by dissolving 1g of HgCl2 in 50mL of distilled water.

Cut 40g of aluminum foil into small squares approximately .5cm a side.

Place the aluminum into a large beaker or other suitable glass container and cover with the sodium hydroxide solution. Heat gently in a well ventilated area until hydrogen gas evolves vigorously for about 3 minutes. Strain the foil through a plastic colander and wash first with distilled water, then with denatured alcohol. Pat dry then add to a beaker with the 2% HgCl2 solution. Allow to amalgamate for 2 minutes then pour off the supernatant. It is unethical to pour mercury compounds down the drain, but you'll probably do it anyway ;-). Now wash the foil in the colander as before, with distilled water, ethanol, and then a little bit of ether. Submerge the aluminum amalgam in ether to store until use.

[edit] OOps.. this method uses Naoh in dh20, not hg in solvent.. but still uses Hg..

https://www.thevespiary.org/rhodium/Rhodium/chemistry/eleusis/aluminum.html

& I'm, somethin of a phenom, no need for da cron, I'm un-stopable.   
 

[lab_bitch]

Amalgamation means that the Hg is adsorbed on the Al surface, so the water doesn't really contain any HgCl2.

[Disciple]

I've got shitloads of Al powder(fine) lying around and was wondering whether it would be worth trying to boost efficientcy by combining this with the ketone dripping it in. So that the reaction only proceeds at the same rate as the addition. What do you Think

[SPISSHAK]

Aluminum powder reacts real exothermically in this reaction, try it and let us know how it works, but try to avoid run away reactions.

[Aurelius]

powder additions are usually not made as slurries in small scale production.  it's hard to keep the suspension up- the aluminum will settle and clog your addition funnel.  try adding it through a wide center condensor and wash it down with a couple mls (5-10) of methanol each time.

[Disciple]

Yeh I was wondering how would be best to keep the al powder suspended. would it be possible to make an emulsion or something or am i just talking outta my ass.
How do you mean to add it through a wide center condensor.
THanks.

[goiterjoe]

Wouldn't you want the aluminum to be amalgated before the reduction begins, or is there an advantage to letting the aluminum amalgate during the reaction?  I was under the impression that you want all of the aluminum to amalgate before the reaction.  On the other hand, you wouldn't want to use aluminum powder for nitromethane as it would get way too hot.
If at first you don't succeed, try, try again. Then give up. There's no use being a fool about it.

[SPISSHAK]

Salts have a tendancy to complex with a lot of things, especially amines, so it would make sense to so this first, rinse the excess off with water, then procedd with reduction, and not to amalgamate in-situ.

[Aurelius]

aurelius only meant to give a suggestion on how the addition could be performed.  didn't mean to suggest that this was a viable or preferred method.  the suggestion is only there if somebody would like to try this variation.  - come to think of it, it probably wouldn't help at all and would probably cause a couple of problems with the cleanup.  the aluminum added later wouldn't have any mercury salts to amalgamate it after the start of the reduction. (excess washed off the pre-prep'd aluminum)  so you'll just have excess aluminum powder floating around.