Cappy - 29-3-2003 at 22:36
I passed current through two steel finishing nails in a salt water solution.
I used a model rocket ignition system which had four 1.5 volt AA cells in series (for 6 volts).
I let the apparatus run for about an hour, and pour the contents through a coffee filter to extract the iron oxide powder. Not counting what was
impregnated in the coffee filter, I got a quarter-sized pile of iron oxide powder.
Do you have any suggestions for increasing the rate/efficiency of reaction?
Should I:
-place electrodes further apart/ closer together?
-increase/decrease salt concentration?
If I tried using a series of many 1.5 V cells, how many do you think I could put in series without risk of overheating when used for periods of an
hour or so?
dont bother with this
blazter - 30-3-2003 at 12:02
Do yourself a favor and take a trip the scrapyard or something. There literally mountains of rust there. I personally managed to find an old
galvanized water tank that was full of rust and managed to easily fill a 1 gallon paint can with it. Remember, if you intend to use simple rust for
thermite you'll need to dehydrate it by strongly heating it, otherwise the water that will be evolved will kill the reaction.
Cappy - 30-3-2003 at 12:50
Yeah, I had baked the iron oxide for a few minutes at 200 degrees F (I didn't want escaping water to scatter the powder). Then I baked it again
at 250 degrees F (worried about it or the paper towel/aluminum foil it was on decomposing). It was my first time, so I was very cautious and paranoid.
Thanks for the tips. This will make my life a lot easier if I can just get to a scrapyard.
why bother?
forundretfrede - 3-4-2003 at 04:59
I just can't understand why anybody would bother to make their own iron oxide. Ceramics suppliers, paint stores and som DIY.stores sell iren
oxide as a pigment. It's low cost, finely powdered and easy to use......
(I like the idea of using the scrapyard as a source. One mans garbage is another mans treassure)
Cappy - 3-4-2003 at 13:01
Well, actually for me making it at home is more convenient. I don't really need large amounts for now. I already have equipment for iron oxide by
electroylsis. I wouldn't need to look for a store that has the stuff. Also, I'm a bit hesistant (not so much with iron oxide and aluminum)
about buying tons of suspicious materials since I'm only 18 and people don't assume "I need stuff for my garden." My friends and I
walked into a gunstore to get some black powder, but then I decided that the owner was way too suspicious of us, so I didn't ask him. He could
tell we didn't fit the redneck stereotype. 
Also, it's more fun to make stuff experimentally (at least once). Thanks for trying to make my life easier though. I'll probably end up
buying aluminum powder from a paint store.
[Edited on 4/3/2003 by Cappy]
Iron oxide by electrolysis
Theoretic - 18-6-2003 at 06:52
Just a tip: iron oxide that you get from electrolytical oxidation has magnetic properties, while rust doesn't (dehydrate the black scum from
electrooxidizing to make it magnetic).
chemoleo - 26-7-2003 at 21:06
uuh, only Fe2:Fe2O3 (Fe3O4, black) is ferromagnetic. In solution, with O2 present (i.e. rust) I would doubt very much that the Fe2+ (i.e. FeO) would
ever form (in nature, all u will find is Fe3+ except some rare minerals maybe .. like Fe3O4, which is stabilised by complex formation however). so all
u will get is iron hydroxide/oxide/carbonate, which, upon dehydration at high T forms Fe2O3.
[Edited on 27-7-2003 by chemoleo]
Basement Chemist - 27-7-2003 at 04:24
you take a bucket of salt water, and you go buy steel wool(the finest, ie thinnest, kind) you can, throw it in the bucket, and come back a few weeks
later
slow, but gets the job done with no work done by me.
chemoleo - 27-7-2003 at 09:04
good idea... make sure u add some salt as this will speed up the reaction.... it acts as a catalyser (i.e. rust on cars gets much worse if you drive
thru salt water etc)
markx - 9-9-2003 at 04:29
To Cappy....
If you want to increase productivity up the salt concentration and put electrodes as close together as you can.
That will decrease resistive losses in your cell.
Duster - 5-10-2003 at 20:05
Hey I did this, mostly just for fun (I have plenty of rust) but I have a few questions...
I did this in a glass jar, with two nails attached to a 12 car battery charger. What I would like to know is why the hell my rust is cyan in color
(blue ish green), or, if that is rust at all. My water (with table salt added) turns a nice green color in no time and these plumes of what has the
shape of fungus (look and shape anyway) form on the bottom and top. Most is that cyan color, some is rust colored but not much.
Also the gases that are formed, I know O2 and H2 right? But I also heard chlorine gas is formed? Is this true? Thank you all very much.
[Edited on 6-10-2003 by Duster]
You have ferrous chloride
chloric1 - 21-10-2003 at 10:38
About 15 minutes before I assembled my clay pot sell with an iron welding rod as anode and lead as cathode. The electrolyte is NaCl. The ions are
off to the races!
I can tell you this, NaCl is MUCH more condcutive than MgSO4. I used the epson salts to "charge" the clay pot with ions.