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How to make Iron (III) oxide

  1. Aug 22, 2012 #1
    Good day to you all.
    A few days ago i attempted produced Iron oxide (III).
    Here is what i have done:

    What i have done 1: I put water in a plastic container

    " 2: I added salt (3 tablespoons) to the water

    " 3: I applied electricity (11.3 Volts) to the water

    " 4: About 3 to 4 hours later, the water started to turn into a very dark green

    " 5: I separated the greenish stuff using a coffee filter

    But the substance was green and not a reddish yellow substance.
    I am trying to produce a large scale of iron oxide but i am unable too :/ and i was wondering, how do they produce a large scale of iron oxide (III)?
    Can someone help me?

    Thank you :)
  2. jcsd
  3. Aug 22, 2012 #2
    Did you add an iron source? By salt, do you mean NaCl? How are you applying electricity?
  4. Aug 22, 2012 #3
    I added 2 nails attached to the positive and negative
  5. Aug 23, 2012 #4


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    Were those nails stainless steel? If so, you made a soluble Cr+6 salt.
  6. Aug 23, 2012 #5
    I don't think so.
    I am looking for ways to make a large scale of iron oxide.
    What clues am i missing for this?
    I only get this green stuff
  7. Aug 24, 2012 #6


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    Soak uncoated steel wool in common chlorine bleach (like Clorox bleach). The sodium hypochlorite in the bleach will oxidize the iron in the steel wool to iron(III) oxide, which will settle as a fine, red powder at the bottom of the container. You could also use iron nails as your iron source, but it will take longer since there is less exposed surface area. You can also substitute hydrogen peroxide for the bleach, but it is more expensive. Do you not use bleach and hydrogen peroxide at the same time because the two will react with each other and produce oxygen gas (bubbles), instead of oxidizing the iron.
  8. Aug 24, 2012 #7


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    Are you going to attempt a thermite reaction? I think it's suitable for this forum as it's a common chemistry demonstration. I'd recommend just buying the iron oxide and especially the aluminium powder if you are.
  9. Aug 24, 2012 #8


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    Staff: Mentor

    Just because I haven't posted, doesn't mean this thread is not being watched.
  10. Aug 24, 2012 #9


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    Borek is probably the guy to clarify with- might as well. It wouldn't surprise me in the least if this was a thermite related thread, but is that an issue? I suppose it's a grey area- the thermite reaction is a common demonstration, though the rules forbid discussion of pyrotechnic/explosives manufacture at home.

    It's pretty clear you're thermite hunting, because I've seen the nails in water technique published a million times. I'm not sure why when iron oxide for colouring cement is available in large amounts, plenty pure enough for a thermite reaction and for a low cost. Same goes for aluminium (cold casting). Easier to buy it.

    Guess I should say that what I've said shouldn't be done at home and only in a controlled environment. If what I've said is "out of bonds" then my apologies, and feel free to remove it.
  11. Aug 24, 2012 #10
    ok mate, i will try that later ;)
    I am currently in the process of trying to increase the production (milligrams to grams) but i don't see how.
    Should i put something metal inside the water container (besides the cathode and anode)
  12. Aug 24, 2012 #11
    Yes, its a thermite.
    I will buy it if i have no option.
    But until then, i will try to make iron oxide and i will blend aluminium
  13. Aug 24, 2012 #12
    You are correct!
    I am trying to make thermite, but i am unable to make "Decent" productions and i get this green stuff

    Translation for "decent"= More than a couple of miligrams
  14. Aug 24, 2012 #13


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    I think you're probably outside the bounds of the rules at this point. Kids improvising pyrotechnics, explosives at home and hurting themselves is certainly one thing the rules are to avoid.
  15. Aug 25, 2012 #14


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    Making rust is one thing... discussing the best ratios of iron oxide and aluminum or how best to ignite it is something totally different.
  16. Aug 25, 2012 #15
    Right. Thermite reactions like this will burn at 7,800 F, emit a blinding white light, and the heat makes the process difficult to contain, since almost anything that holds the mix will melt at a much lower temperature than 7,800F.
    And even if you did have a proper container/ funnel, if there is any moisture at all present in your work space, any molten metal hitting it will turn the moisture into steam, and the water will instantly expand 1700+ times its original volume. So you'll have a steam explosion scattering molten metal everywhere.
    This is the kind of thing you have to be aware of when melting metals (aluminum, bronze, iron) in home made charcoal furnaces foundries, and they only can hit maybe 2400F, if you're really lucky. The risks are the reason I didn't build one of these foundries about 15 ago. (all the kids in my neighbourhood hung out in our back yard after school).
  17. Aug 25, 2012 #16


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    Indeed. Don't bother trying to stop a thermite reaction, just let it finish. Do it on something non flammable that wont melt (i.e. ceramics, though they can often break). Plenty of space with nothing flammable nearby is the way to go. I certainly wouldn't do it inside a lab.

    Look, if it's not against the rules, then I can tell you straight up not to bother making the ingredients. They can be purchased legally and fairly cheaply (of course you're only doing small, safe demonstrations, not breaking into places aren't you?). Blending aluminium foil is a surefire way to fail. They're both time consuming ingredients to produce and it works out far cheaper to buy them.
  18. Aug 25, 2012 #17
    Thermite welding is used by some industries, and I have met at least one person who has done this.
    Given that one might do this as part of their work, say to repair cracks in cast iron engine blocks (or so I was told), I suspect there will be guidelines on doing this work ~safely~ somewhere up on line, probably at he OHSA websites. (Occupational Health and Safety Administration or some such).

    Safety is to be thought out diligently.
    Even pouring molten metal onto "dry" concrete can lead to bad ends, since the concrete isn't really dry, but will contain a certain amount of water for most of its existence. (concrete is porous and wicks water nicely. That's why we now place poly plastic underneath it in construction)
    Eye protection is absolutely mandatory, and some kind of heat-resistant full-body suit is strongly advised. A blacksmith's leather apron over top that would help, too.

    Some college Chemistry textbooks will have a small bit about thermite welding. Mine does.
    Last edited: Aug 25, 2012
  19. Aug 25, 2012 #18
    You got a point on that, but i am not a kid and i am a student in Aerospace Engineering.
  20. Aug 25, 2012 #19
    That is very cool ;)
    Last edited: Aug 25, 2012
  21. Aug 25, 2012 #20
    I will buy them as a last option, but until then, i am going to try to increase the production.
    Which currently, i am unable to...
    But still trying tough and i am not gonna stop until i find a way to increase my production!
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