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Another Iron Oxide question

  1. Sep 15, 2007 #1
    Ok, so I decided to make some rust. I had some steel wool lying around and decided to try the water/bleach/vinegar solution.

    I put 2 pieces of steel wool into a glass mason jar in the solution that covered the steel wool by about an inch. Then I put a plastic container over it to keep the bugs and stuff out (done outside). After 4 days I go to empty it and I find that the steel wool looks like it did when I put it in there I stir it up and pull out the steel wool and filter the mix. I have enough to scrape off but the amount is so small.

    Here is the question... Did my plastic container block O2 from getting in there slowing down the process? Did I get over zealous and try to convert too much steel wool? And the last question... Would using an aquarium pump and feeding a hose into the solution speed up the process?

    I have since replaced the plastic cup with some fiberglass cloth and I bought a small pump to oxygenate the water.

    Am I way off base here or is the process just so time consuming?

    Thanks
    John
     
  2. jcsd
  3. Sep 15, 2007 #2
    One thing I think needs to be taken into here with steel wool is that, some if not all brands have some kind of a light coating of oil or wax or rust inhibitor of something to keep it from rusting between manufacturing and final sales.

    I would think not removing this prior to experiment would result in some kind of problem.

    Jim
     
  4. Sep 15, 2007 #3

    mrjeffy321

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    What type of bleach did you use?
    What type of steel wool did you use?

    The Oxygen which goes into making the Iron Oxide does not come from the O2 in the air but rather the Oxygen in the beach (Sodium Hypochlorite, NaOCl). You do not need to worry about the liquid being exposed to air or oxygenating it with an aquarium pump.

    When done properly, you should see results in a few minutes/hours; it should not take 4 days.
     
  5. Sep 15, 2007 #4
    Guys, thanks for the replys.

    Here I used Clorox bleach and Rhodes American Steel wool Super Fine #0000

    Mason Quart jar 2/3 full with water
    2 steel wool pads
    5 table spoons vinager
    5 table spoons clorox regular bleach

    Hope this Helps.

    If the pads are treated to prevent rusting is there an easy way to remove the coating?

    Thanks Again.
    John
     
  6. Sep 15, 2007 #5
    Oh, I almost forgot...

    When I was filtering the rust I noticed a iridescent sheen substance on the top of the water kinda like oil in water. Is this maybe the coating or just a normal part of the process?

    Thanks
    John
     
  7. Sep 15, 2007 #6

    mrjeffy321

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    There is your problem….
    You did not have much NaOCl there, and it was quite dilute.

    Why did you dilute the bleach so much?
    There is no reason to add any water to the reaction. Just submerge the steel wool pads in bleach solution.

    The steel wool pads you used are absolutely fine, as is the type of bleach you were trying to use.
     
  8. Sep 15, 2007 #7
    Hmmm... Well that would be because I was following what is obveously an incorrect recipe. :)

    Is then the vinager still needed or just bleach?

    Thanks
    John
     
  9. Sep 15, 2007 #8

    mrjeffy321

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    Using just bleach will work, the vinegar is not required.
     
  10. Sep 15, 2007 #9
    Thanks for your help. I'll give that a try.

    One last question. I'f I'm doing this outside in open area and I'm using a face shield and a two filter face mask should I have anything to worry about? I've been reading alot on this process and the ill effects are nasty. I just want to make sure I'm taking the right steps to be safe.

    Thanks
    John
     
  11. Sep 15, 2007 #10
    Ok, so that wasn't the last question, sorry.

    How safe is it to dry the iron oxide in the oven.

    If I drain the rust and then rinse and drain again would it be safe to handle at that time?

    Thanks
    John
     
  12. Sep 16, 2007 #11

    mrjeffy321

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    The only thing I would be worried about while this reaction is taking place is the harmful fumes which will be evolved. The face shield and 2 [paper-ish?] filter face masks will do very little to protect you from breathing these fumes in as they are designed to keep solid out solid and liquid particles. But then again, there is no reason why you should be standing over the reaction the entire time anyway. Just go inside for a while and periodically come out to check the reaction (see if the bubbling has stopped / stir the mixture).

    Yes, you could dry the rust in an oven (assuming you choose an appropriate container). But, from what you have described, you will not be making all that much rust and it should be pretty easy to simply decant off the water and dry the rust in direct sunlight too.
     
  13. Sep 16, 2007 #12
    What exactly is the point of the vinegar idea, chemically? Is it supposed to generate free chlorine gas? I don't really see how it would speed things up- if anything it makes the bleach solution diluter.
     
  14. Sep 16, 2007 #13

    mrjeffy321

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    Chemically, I am not certain what the role of the vinegar is.
    I have been told that it acts to catalyze the reaction between the Iron and the bleach and there is some qualitative evidence to support this. But adding an acid (like vinegar / acetic acid) to bleach should result in the release of Chlorine gas and the destruction of some of the bleach in the process…so I am not sure how this helps the reaction.
     
  15. Sep 16, 2007 #14
    When I go outside to check on it and stir it I don't stand over the solution and and not for a prolonged time either, but when I go out there I put on the "twin cartridge respirator"and the face shield.

    I was going to ask the same question :)

    Are there any harmfull bi-products from doing a just bleach solution?

    What a metal baking sheel or pan?

    thanks
    John
     
  16. Sep 16, 2007 #15

    mrjeffy321

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    I would not be overly paranoid about the ill-effects of the fumes but, never-the-less, do not be careless. Just use common sense…if it doesn’t smell good and makes you cough, then don’t breathe it and get out of the area and to fresh air.

    During the peak reaction time, fumes will be given off which will smell an awful lot like Chlorine gas (whether you use vinegar or not), so make sure you do this outside and in a ventilated area and don’t breathe these fumes. Doing this on the scale you described (mason-jar quantities or less), the risk is minimized.

    The choice of container material you use to dry the Iron Oxide in is only of slight importance for your scale of operation. Heat resistant glass / ceramic would be the ideal choice, but Steel or Aluminum will also work (but they will corrode slightly), and obviously plastic is out of the question if your going to dry it in an oven.
     
  17. Sep 16, 2007 #16
    Sounds good, I'ill keep myself safe.

    Thanks for all the answers to my guestion and all the good advice.

    John
     
  18. Sep 17, 2007 #17
    Ok, so I got home today and the iron oxide was bubling.

    Last night I had strained the rust into some coffee filters and let it sit for a while. After a couple hours I went outside and scraped off the rust and put it into some water (just water) and let it settle. This morning I got up and it had all settled to the bottom and the top of the water was somewhat clear. When I got home I was going to dump out the watter and rinse again but thats when i noticed it was bubling. and it had stired its slef up a little bit. I went ahead and poured out what I could and added some more water. Next I'm going to fileter it again and try one more rinse.

    Any idea why it was bubling with just water?

    Thanks
    John
     
  19. Dec 5, 2007 #18
    I tried this yesterday with:
    -Bleach solution
    -Cooking vinegar (containing a little alcohol)

    I did this all in a boiling tube, containing a myraid of stuff (hoping they'll rust). SO i used like a nail, stapler bullet e.t.c...

    By night, the reaction was crazily slow and so i carried it out in a water bath/buffer solution with boiling water. THe reaction did accelerate. I got bored and so tried adding some baking soda into the boiling tube (hoping to accelerate the reaction). Then, i left the boiling tube for the night.

    Next morning (right now), there's this crazy grey precipitate like 1/3 of my boiling tube length in my boiling tube now!! the other 2/3's of the boiling tube has become a somewhat oily-yellow based colour (last night before adding the baking soda , the colour was reddishbrown)

    And worst of all...barely any rust at all. So i have a couple of questions.

    1. Did the small amount of alcohol in the vinegar take part in any reaction?

    2. Did the baking soda screw up my reaction? (I know its got nothing to do with the cations here..since its merely Na+ and Fe, but probably something due to the anions??..not too sure)

    3. I have no clue if i'm using steel nails or iron nails. But i sadly think that its the former. Steel nails would barely rust right due to the formation of resistant Chromium (III) Oxide layer right? . Damn.

    Hope someone can clear up my problems.

    P.S: I would like iron oxide to try and make some thermite. haha


    Thanks
    Manraj Singh
     
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