Abromination - 21-7-2018 at 21:46
I need to do make some aluminum powder for thermite, but would like to do it chemically. My ball mill is complete trash and sanding down aluminum is a
waste of my time, and where I live I can't buy it due to shipping. I used to know how but have forgotten how to precipitate aluminum powder in a
reaction. Would I start with sodium aluminate from dissolving aluminum in sodium hydroxide? If so, how would I proceed to turn the sodium aluminate to
aluminum? If there is another way I would love to hear.
JJay - 21-7-2018 at 22:08
That's a tough one. If there's an easy way to make aluminum powder chemically, I think a lot of people would like to know about it. If only it were as
easy as electrolysis of aluminum sulfate in acetone....
Abromination - 21-7-2018 at 23:54
Thank you. I feel like a complete idiot asking this, but what kind of electrodes for the cathode and anode?
JJay - 22-7-2018 at 00:11
I really don't know... graphite maybe? There are a few commercial electroplating solutions for coating objects with aluminum. None of the solutions
contain water.
j_sum1 - 22-7-2018 at 00:45
Aint gonna happen.
You need this table of standard reduction potentials. Two important lines are made bold: those related to H2gas and O2 gas from water. Between these two
lines are all the reactions that can be done in aqueous solution. Al is well out of that range. Attempting to reduce Al in solution will only result
in reduction of water to H2. There is a reason why aluminium reduction takes place at nearly 1000C with Al2O3 dissolved in molten cryolite and no
water in sight.
Now, to be fair, the table is for standard conditions. You can obtain a bit of wiggle room by adjusting the concentration, playing with the pH and
temperature and applying overpotential. But not enough wiggle room to give you Al powder. Time to get out the angle grinder.
Abromination - 22-7-2018 at 01:00
Oh well. Back to hammer brittling and crappy ball mill for me. 
symboom - 22-7-2018 at 02:29
Dont touch that ball mill
Aluminum can be reduced look up the ffc cambridge process all you need is calcium chloride molten and add aluminum hydroxide as a paste apply to
graphite electrode then bake it then you have aluminum oxide with a propane torch melt the calcium chloride with the electrodes in the cathode
contains the aluminum oxide to be reduced by the calcium it will produce carbon dioxide due to the aluminum oxide the oxygen is caried to the anode
and the oxygen reacts with carbon rods
As itvis being produced
660.3°C melting point of aluminum
772°C melting point of calcium chloride
842°C melting point of calcium metal
Aluminum powder is produced just break up the clumps
[Edited on 22-7-2018 by symboom]
DraconicAcid - 22-7-2018 at 06:05
Is aluminum oxide soluble in molten calcium chloride? You'd think they'd use that instead of the more expensive and difficult-to-work with cryolite
for the Hall process if it was.
symboom - 22-7-2018 at 07:08
Quote
The FFC Process, developed by Metalysis, is an important new technology for producing tantalum, titanium and other metals from the oxide. The FFC
Process works for a vast range of metals, alloys and carbides with significant economic and environmental benefits over existing processes.
Its probally patented from https://www.metalysis.com
I cant wait for titanium prices to drop
They used to have a page of the elements and all the metals that can be produced it only possible because the calcium metal desolves in the molten
salt and reduces oxides
I have been wanting to try this out my dc welder should work i have to get it working again. The hardest part of the process would have to be getting
the oxide stuck to the graphite so it can be reduced by the calcium that is formed sience aluminum oxide is non conductive
Note
TiO2 is electrically insulating with an extremely high resistivity above 108 cm, but the suboxidized TiO2 with an excess of titanium is an n type
semiconductor with unique properties
Simular to sodium suboxide
Here is what is going on chemically
CaCl2 + Al2O3 +CaCl2 + electricity
Calcium metal + Al2O3
Calcium oxide + Al metal + O2 at anode
CaCl2 + CaO + electricity yields calcium metal
A set up of this would be a great idea for prepublication
[Edited on 22-7-2018 by symboom]