Iron Oxide (Rust)

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Sat Sep 15, 2007 1:17 pm

I need to make some rust... lots of it. (I won't say what for though!)

I got 4 packs of super fine steel wool from Home Depot yesterday. I read somewhere to put steel wool in a bucket with water and then add in bleach and vinegar.

My question is, why add bleach and vinegar? And how much of each?
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Fnord
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Sat Sep 15, 2007 2:09 pm

I can't remember what the exact ratio was, but something like 1/4 vinegar, 1/4 bleach, 1/2 water (by volume) should work fine.
You'd be better off hooking the steel wool up to a small dc tranformer, though.
I've always found electrolysis to work better than the chemical reaction. I believe bleach and vinegar create a stronger acid that allows the iron to oxidize faster, but that's just a guess.
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thespeedycicada
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Sat Sep 15, 2007 2:53 pm

just use bleach thats what i use.
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iPaintball
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Sat Sep 15, 2007 3:06 pm

Lemme guess, thermite? What fnord said is right though. Electrolysis works great.
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Sat Sep 15, 2007 3:10 pm

heheh...

Probably another stupid question- How do you use electrolysis for this?
Blackett
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Sat Sep 15, 2007 3:12 pm

If that;s what your making be careful.

but yeah it's.25 bleach, .25 vinegar, and .5 water.

and electrolysis ftw. It's waaay faster than just letting the stuff sit. don't forget your 400 mesh aluminum from any of the compendium of suppliers that sell it.
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Fnord
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Sat Sep 15, 2007 3:22 pm

Probably another stupid question- How do you use electrolysis for this?
All you really need to do in this situation is get a big plastic bowl of water, then take your transformer and hook up a couple big gobs of wool to the wires.
Put them in the bowl so the two ends aren't touching directly and you will start to see rust forming withing minutes.
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PVC Arsenal 17
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Sat Sep 15, 2007 3:34 pm

I'm going to try submerging the wool in water with a fish tank aerator pumping up from underneath. Air + water should work.
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benstern
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Sat Sep 15, 2007 3:37 pm

Use black iron oxide (black sand) from the beach! It is superior to rust in thermite reactions
Blackett
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Sat Sep 15, 2007 5:23 pm

oh wow. thats the most useful tidbit of info i've seen all day.

thanks ben


if your gonna be as simple as the fish pump might as well just use the electrolysis.
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Sat Sep 15, 2007 9:37 pm

I might have once tried to make thermite- it didn't work :(
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Sat Sep 15, 2007 9:39 pm

Let's get off the subject of thermite. It's probably against the rules.

Lets just say I'm doing a chemistry project...
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boilingleadbath
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Sun Sep 16, 2007 2:58 pm

I have made iron oxide through two processes:
1) Rusting steel wool on a plate. 56g very fine steel wool, sprayed with vinegar every once&while... took 2 weeks, IIRC. (in basement, so a bit cool)

2) Electrolysis of scrap steel in (sodium chloride) electrolyte. (Only the anode is consumed)
Even with a 1 amp max/12 volt power supply, this was a lot faster.

#2 produces iron hydroxide, IIRC.. but a few hours in the oven fixes that. (Fe(OH)3 -> Fe2O3 + H2O)
The bit of extra work is worth it, however, as the particles seem to be quite a bit finer. I use the stuff mostly as a burn rate catalyst (not as an oxidizer), so I feel this is important. Your priorities may vary.

Bubbling air up through a water solution will work; I've heard that it helps to have iron chloride in the water. (the synth for iron chloride is easy; rust & hydrochloric acid, wait a few hours)
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