Sciencemadness Discussion Board

How to make rust?

AnAspiringChemist - 23-7-2015 at 19:52

Is there a quick reaction that can yield high amounts of rust with ordinary household materials without any electrolysis? Which form of iron will produce high amounts of rust efficiently?

Bert - 23-7-2015 at 20:47

Try taking the finest grade of furniture finishing steel wool you can obtain, wash it twice in a solvent such as alcohol or acetone to remove the preservative oils applied by the manufacturers, mist it with a concentrated salt water solution and place it in a warm, high humidity environment.

Made mixed Iron oxides/hydroxides very quickly this way for my first thermite mixture experiments, 40 or so years back...

No idea what the actual mixture of oxides/hydroxides produced was. It oxidized Aluminum or Magnesium powders just fine, regardless.

Pumukli - 24-7-2015 at 01:00

When I was a kid I collected my "Fe-powder" (actually not powder but very small bits from sawing steel pipes by a hand SS saw) by a big magnet. I collected a few tablespoonful.
To my surprise when I submerged this "powder" in a bucket of fairly pure rainwater and then immediately drained it the rust was quickly forming! It was long ago and I don't want to boost my statements but I remember as if the discoloration (rusting) happened visibly, in a few seconds (maybe minutes), as the "powder" was drying in the sun!

So all you need is as fine the Fe as you can get, some water and mybe some electrolytes (salt) would help as well, as Bert suggested. Nitrate salts may be even better.

NedsHead - 24-7-2015 at 05:38

Some things just aren't worth the trouble, it's worth exploring the chemistry once or twice but if you're after a usable supply of oxide to play around with it's not worth the time and Labour. Just go to the hardware store and buy it

MrHomeScientist - 24-7-2015 at 05:51

eBay also sells iron oxides in many-pound lots. I just bought 10 pounds a few weeks ago, for some thermite demonstrations. It's almost certainly cheaper than rusting your own iron - iron has to be made from rust in the first place, so surely the starting material is less expensive!

Bert - 24-7-2015 at 06:07

eBay Iron oxides are a VERY mixed bag-

From personal experience and from testing done on Iron oxide catalyzed whistle mixes, cheap red or black oxides sold on eBay as ceramic glaze materials or otherwise not closely specified have been everything from powdered Iron ores to steel mill scale to (very occasionally) a reasonably pure and consistent chemical. I guess amateur pottery makers enjoy the surprising variety of glaze effects that come out of the kiln...

The oxides sold as paint/stain pigments or for cosmetics use are more regular.

MrHomeScientist - 24-7-2015 at 07:03

Interesting. I have noticed some variation between suppliers as far as color and consistency, but everything has always worked for thermite (which is all I ever use it for). Alpha Chemical is my latest supplier and they appear to have some good quality chemicals all around.

Texium - 24-7-2015 at 07:39

Quote: Originally posted by MrHomeScientist  
Interesting. I have noticed some variation between suppliers as far as color and consistency, but everything has always worked for thermite (which is all I ever use it for). Alpha Chemical is my latest supplier and they appear to have some good quality chemicals all around.
I bought a pound of iron oxide from AlphaChem also. It works well for thermite, and seems pure enough at least for pyrotechnic purposes (which seems like what the OP would be intereted in) although some of their stuff is rather hit or miss. The manganese sulfate that I bought from them was gray and smelled like sulfur dioxide. It was easy to purify though. It appeared to be contaminated with MnO2, leading me to think that the MnO2 + SO2 reaction was used and just didn't go to completion. The crystals that I got from filtering and recrystallizing it are very pure. Even though I had to go to all that trouble I think it was worth it since two pounds of the stuff was about $4.00

MrHomeScientist - 24-7-2015 at 09:30

I guess the problem is most are just resellers, so they buy their products from lots of different sources. I had troubles with another seller, gumby96 (gumby-somenumber, at least), where MnO<sub>2</sub> was cut with sand. Nurdrage made a video on it. Other stuff I bought from him had been great, but after that incident I avoid him. Hit or miss indeed.

Pyro - 24-7-2015 at 10:10

buy a boat!

you can buy rust as a pigment in some art stores too

AnAspiringChemist - 24-7-2015 at 16:10

i was thinking about using steel wool and putting it into some vinegar and or bleach. Problem is, my steel wool is coated in this blue soapy material. How can i remove this?

UC235 - 24-7-2015 at 17:41

Quote: Originally posted by AnAspiringChemist  
i was thinking about using steel wool and putting it into some vinegar and or bleach. Problem is, my steel wool is coated in this blue soapy material. How can i remove this?


Go to the hardware store and buy steel wool instead of brillo pads with soap from the supermarket. It's not worth trying to clean them off.

Pumukli - 24-7-2015 at 21:12

If you already bought them: make a campfire (outside) and toss them in! :-) Soap should not resist this treatment, iron should. It might get some rust as well. :-)

kecskesajt - 25-7-2015 at 10:10

But the steel wool will burn.
Pumukli: Are you Hungarian?

AnAspiringChemist - 25-7-2015 at 13:31

i want to use the steel wool i have. how would i remove this blue soapy material? vinegar?

aga - 25-7-2015 at 15:05

Just wash in water a lot.

Easier: just toss them in a bucket of water with bits of old iron, nails etc and wait (maybe stir every day).

Eventually you will have a layer of iron oxide to harvest from the bottom of your bucket.

If you want a lot, add more buckets.

AnAspiringChemist - 26-7-2015 at 23:39

if i was to use bleach and vinegar with steel wool, how much rust do you suppose i would be able to get in grams after filtering?

AnAspiringChemist - 4-8-2015 at 10:15

you twits didnt reply!!?!?!

Pumukli - 4-8-2015 at 11:15

Twits?

Haven't you read the rules?
According to rule number mmm, sumting, clairvoyance is not expected from anyone on this forum.

So before we could give any meaningful answer we may would like to know how much Fe that "steel wool" blob actually contains!

Doh! :-)

Ozone - 4-8-2015 at 14:58

If you want rust very quickly, add 9% hydrogen peroxide [what I tested; diluted from a (titrated) 30% solution to mimic the material available for hair bleaching] to your filings/wool/whatever and a tiny (catalytic) pinch of rust you may have on hand (this works best if your iron/steel has a small bit of rust to begin with). The reaction should be surprisingly exothermic (it may boil depending on peroxide strength), and yield nice rust in seconds.

O3

Rust

Camroc37 - 4-8-2015 at 16:04

You can use bleach to speed up the rusting, then filter. A quicker way is mixing vinegar and bleach, as the chlorine can help the rusting. This does make a small amount of chlorine gas, so do this outside or in a fumehood.