I know that allot of amatuer chemists try to make thermite and that one of the problems they encounter is how to produce rust. It would seem abundant
enough when it's an annoyance but now that you do how do you make it?
I'm not quite sure if anyone else put up a post about this or not but an easy rust recipe involves steel wool, hydrogen peroxide, and sodium
chloride.
All you have to do is submerce the steel wool in the H2O2 and throw in a dash of salt. Immediatley hydrogen gas will be generated along with heat that
will spead up the process. all that's left to do is filter and dry.
If anyone knows of this process please let me know and whether or not it can be improved.Tacho - 19-6-2004 at 02:43
I respect anyone who wants to do it by himself. But I am curious: why not buy it a hardware store?
Is it unavailable somewhere? I mean, as concrete/cement powder pigment?Saerynide - 19-6-2004 at 03:23
How does the salt fit into the equation?Organikum - 19-6-2004 at 06:33
By heating black cement-pigment to over 180°C in air you get very good rust. Eh, FeO3 of course.
You can determine if the black pigment is iron based by using a magnet. If it sticks to the magnet it is the real McCoy.
Thats easier than peroxide I guess?BromicAcid - 19-6-2004 at 06:49
This is a variation of the electrochemical rusting process where one part of the iron acts as the anode and one as the cathode. The purpose of the
NaCl is to increase conductivity between the different iron surfaces in the container. Another site said it was carbonic acid from dissolved carbon
dioxide from air that sped up the rusting process but around my area were it gets cold it is the salt from the roads.sanity gone - 19-6-2004 at 07:29
The method you mentioned works, but you have to wash the wool first. Use small amounts of dish soap and place it in the oven to remove the coating.
Then all you have to do is add Hydrogen Peroxide and a pinch of salt.
Also, if your going to make Al powder, you can either get it from an Etch-a-Sketch. I'm trying to make Al powder by dissolving Al foil in HCl and
using Mg to percipitate the Al and then taking the motar and pestle to it.unionised - 19-6-2004 at 09:43
I doubt that you will get any aluminum powder that way.vulture - 19-6-2004 at 13:18
Captain obvious says:
Fe3+ salt + OH- ----> Fe2O3.xH2O
Fe2+ salt + O2 + OH- ----> Fe2O3.xH2O
Oversimplified the equations, but it works.
Even for BULK with big B.guy - 8-7-2004 at 18:46
Will this method work to make other metal oxides?unionised - 10-7-2004 at 06:22
Usually. There are exceptions, the alkali metals form soluble hydroxides so you can't precipitate them and filter them off.
If you try it with silver you have to be careful heating it or you get the metal, not the oxide.
Synthesis of fe2o3 by means other than electrolysis?
hdcwr0x2 - 14-5-2005 at 15:48
As title states. Anyone know of a good method for producing small quantites? I'm hoping to experiment in thermite welding.12AX7 - 14-5-2005 at 16:50
Well uh, besides weathering metal... you can always dissolve in acid and precipitate it. Or mine it in any number of ways, depending on your geology
(the crust is 8% Fe after all, with >40% concentration being industrially viable). Black sands for instance.
TimFrankRizzo - 14-5-2005 at 21:30
For thermite, you really want Fe<SUB>3</SUB>O<SUB>4</SUB>. It's much cleaner (doesn't leave red stains everywhere)
and produces more molten product.
Stoich works out to ~1:3 Al/Fe<SUB>3</SUB>O<SUB>4</SUB>.
The Fe<SUB>3</SUB>O<SUB>4</SUB> can be produced by unrolling a wad of steel wool, re-rolling it tighly, and then starting one
end of it on fire. A dull red glow will go from one end to the other in a few minutes, leaving you with the goods.
[Edited on 15-5-2005 by FrankRizzo]cyclonite4 - 14-5-2005 at 23:04
After looking at the MSDS's for 'Diggers' Brand pigments (which is the common type you get in Australia), the red pigment is Fe2O3,
whilst the black pigment is Fe3O4. I'm sure that the same applies to any other brand, so if you want Fe2O3, go for the red pigment, if you want
Fe3O4, the black pigment.Mr. Wizard - 15-5-2005 at 06:32
The black iron oxide is available also from welding fabrication shops, or blacksmiths, as black slag from oxy-acetylene cutting torches and as the the
slag from plasma cutters. They will let you clean up the floor of their shop for them. I bring my own buckets, broom, shovel, and gloves. I use the
oxide to provide iron for my garden, but there is always a little left over. The plasma cutter stuff is better and more uniform, but is usually in a
water bath under the plasma cutting table, but not always. The cutting torch stuff has chunks of steel in it. Crush it all the best you can, and sift
it through a metal window screen mounted over the mouth of a wide mouth glass jar. A Mason canning jar works well, and the ring will hold the screen.
I use aluminum screen, but even the vinyl coated fiberglass plastic screen will work, but it isn't as durable. Anything not passing through the
screen is saved into another bucket for re-crushing. Shake rattle and roll! For extra fine dust, use a piece of old panty hose over the jar mouth.
I'll attach pictures if anyone is curious. The oxide is stored in PET soda bottles.
[Edited on 15-5-2005 by Mr. Wizard]mericad193724 - 20-7-2006 at 16:57
Could you make Iron Oxide, Fe2O3 by using Ferric Chloride? I have a gallon of it in a water solution. I am guessing that you just mix peroxide with
it, but would that produce chlorine gas???
thanks
MericadThe_Davster - 20-7-2006 at 17:34
Precipitate it with base first. Then add peroxide.12AX7 - 20-7-2006 at 18:21
No need for peroxide if it's already ferric.
TimThe_Davster - 20-7-2006 at 18:44
Ah correct, I was not paying close enough attention. Peroxide is only needed for ferrous.
[Edited on 21-7-2006 by rogue chemist]DeAdFX - 20-7-2006 at 18:44
I find HCl/NaOH method a real bitch. Its really difficult to isolate the product in a timely fashion. THe Iron Oxide that percipitates out is
incredibly fine and takes a long time to settle to the bottom. Decant, refil with water, wait, decant, refill, wait, decant.... I wish I could just
magically remove the Iron oxide into my glass jar. I ended up with a <10% yeild partly because of my impatience and partly because a huge chunk
of IRon Oxide was decanted accidently.
Ill try the peroxide method mentioned but with oxyclean instead(I ave no "pure" H2o2)
[Edited on 21-7-2006 by DeAdFX]12AX7 - 20-7-2006 at 18:51
Catalytic rusting of iron scrap works fine if you have a bubbler. A stirrer wouldn't hurt either, you can probably get a much better particle size if
you circulate than if you just let it settle.
As-is, I find a very fine particle size, that doesn't settle well when washing.
Calcines to a red-purplish, distinctively Fe2O3 product though.
Timmrjeffy321 - 20-7-2006 at 22:10
Oxidizing Steel wool with Sodium Hypochlorite (in the form of 6% Clorox bleach) always worked really well for me.
Also, adding a touch of vinegar seemed to speed the reaction up, but it is not required.
2Fe + 3NaOCl --> Fe2O3 + 3NaCl
after the reaction is complete decant off the NaCl solution on top and let the Fe2O3 settle to the bottom. Dilute the remaining suspension with ample
quantities of water, let settle, decant, repeat, .....
until the remaining solution is virtually pure water.
The pour this Fe2O3-water slurry into some type of big, flat, container and set it in the sun for a few days to dry.
You will be left with Fe2O3 "cakes" which can be easily crushed into a powder.
This is what I used to do, but now I find it much easier and cheaper to simply buy it in bulk rather than make it.
[Edited on 21-7-2006 by mrjeffy321]praseodym - 20-7-2006 at 22:59
Does it matter to you which type of Fe2O3 that is produced? Because iirc, there are quite a few different forms of Fe2O3, namely alpha, beta,
amorphous, epsilon, and gammatexaspete - 26-7-2006 at 13:57
I too find that the bleach (sodium hypochlorite) and steel wool method works well. Rather than decanting, I simply pour the mix through a filter, and
then rinse a few times with water. After that, spread the filter out to dry.mericad193724 - 15-8-2006 at 11:31
Today I would like to try NaOH and my FeCl3 to make Fe2O3. I just don't understand how Fe2O3 is participated by NaOH, what is the reaction???
Mericad12AX7 - 15-8-2006 at 15:29
It doesn't participate. It is precipitated. And Fe2O3 isn't precipitated, Fe(OH)3 is.
Not counting coordination (ions such as [Fe(H2O)6](3+) (hydrato-), chloro- complexes, and once base is added, hydroxo- complexes as well). Note that
Cl and Na appear on both sides of the equation, so you can write it as Fe(3+) ions combining with OH- ions.
To get Fe2O3 you need to wash, dry and dehydrate (calcine) the product.
Timmericad193724 - 15-8-2006 at 16:00
thanks for the explanation 12AX7...basically what you are saying is the steel wool and H2O2 is much easier and faster!
Mericad12AX7 - 16-8-2006 at 14:09
I'm confused, where did I say that? It sounds like a waste of H2O2 to me (or bleach, for that route...or ferric chloride for the above!).
Being in water, you'll get hydrated oxides from any rusting anyway. You always need to calcine rust.
TimTwospoons - 16-8-2006 at 14:42
Quote:
Originally posted by 12AX7
To get Fe2O3 you need to wash, dry and dehydrate (calcine) the product.
Tim
Eh? When I did it I got a fine black ppt of Fe2O3 immediately the two solutions mixed.
I ran FeCl3 soln slowly into boiling NaOH. The ppt was easily separated using a strong magnet - from an old hard drive. The stuff is
incredibly fine, and messy and gets over everything. This was from my attempts to produce a ferromagnetic fluid.12AX7 - 16-8-2006 at 14:48
Black?? Black is Fe3O4, which certainly forms from solution with little hydration, but doesn't form from FeCl3 without a reducing agent.
TimTwospoons - 16-8-2006 at 17:26
Duh. Should have checked my refs. Fe3O4 (which is actually FeO.Fe2O3 IIRC) was made using a 2:1 molar mix of FeCl3 and FeCl2. I guess my memory aint
what it used to be.
