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Rust Filtration?

  1. Oct 17, 2005 #1
    hey, im new to these forums, i have read a bunch of **** regarding the vinegar/bleach rust-making solution(yes i know about the chlorine) anyways i have a batch going at the moment and i was wondering what would be the best way to get the rust out of the solution?
  2. jcsd
  3. Oct 17, 2005 #2


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    To be perfectly technical, the rust isnt in solution, it is a solid by product of the reaction.
    You can use this to your advantage when removing the rust from the water.
    You could filter it as you have figured out, but as for me, I prefer to decant the water off.

    Decanting is a somewhat slower process than filtration. It involves letting the rust settle to the bottom of the container, then pouring (or in my case syphoning [let gravity do the work for me]) off the clear water. Then let the rust settle some more, and decant some more. You will eventually reach a point where you just cant pour any more water off, this is when I move to a smaller container and try again. Eventually, when I get as much water as practical decanted off, I pour the rust into a large Aluminum pan, the cheap-o kind that might be used for baking (I dont know, I dont cook). The I set it in the sun for a few days, or during the winter, in the water heater closet until it is dry.

    Before removing the rust from the water, I usually try to remove any remaining impurities (NaOCl, NaCl, vinegar) by first dilluting the rust-water mix, let it settle, the decant the water off, the repeat as much as is necesary until I get clean (non-salty) water comming off from ontop of the rust.
  4. Oct 17, 2005 #3
    thanks for the reply, but would this process be the same for the bleach/vinegar mix? At the moment i have steel wool sitting in that, it is almost completely rusted, what do you think would be the best method to extract and dry the rust here? I dont want to bring it inside because of the chlorine vapors. Is there something i can add after i siphon off some of the mix that will get rid of the chlorine fumes?
  5. Oct 17, 2005 #4
  6. Oct 17, 2005 #5
    do you think a coffee filter work?
  7. Oct 17, 2005 #6


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    The method I described is exactly what I do myself when I make rust, using bleach and steel wool (and vinegar as a catalyst), it works really well for me.

    Dont be so worried about the chlorine fumes at this point in the reaction. The reason for the chlorine is because you added an acid (Acedic acid, AKA, vinegar), to bleach, but by now, all the bleach has since been reacted.
    I still wouldnt bring it inside, because if there is an accident and something should spill, it makes an aweful mess (believe you me).

    A coffee filter would work, in theory, but it would depend on how much rust your making. A single coffee filter probably cant take much, you may have to multi-layer several filters.

    I say first purify the mix by diluting and decanting a couple times, then siphon off the water and let it dry in the sun. I think filtering would be tediously time consuming in that it would be slow going with the multiple layers of filters.

    What is your estimated yield of Iron Oxide?
  8. Oct 17, 2005 #7
    thanks for all the help, im first going to try the decanting/diluting method, if this doesnt work i will move on to filtering, my estimated yield is about 14 grams.
  9. Oct 18, 2005 #8
    hey mrjeffy the decanting worked perfectly, im going to keep diluting and decanting, then ill heat the remainder-good tip not to bring it inside lol.

    ps-people DO NOT try coffee filters.
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