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How to make pure iron oxide

I need to know how I can make a large amount of Iron Oxide in the shortest amount of time. I heard I could use a DC convertor and salt water and make it but I can't seem to find a DC convertor. If you know of another way please answer......THANKS

Nicholas McAHAN
Chemicals Hobby - BIG SPRING, TEXAS, United states
2004

A battery charger ⇦ this on eBay or Amazon [affil links] .

Tom Gallant
- Long Beach, California
2004

Well, to get a DC converter is not hard you probably have one just laying around your house from when you were a kid. A simple DC converter is a Toy Train power source. They are variable current and work very well. Afterwards let the iron oxide settle in the bottom of the container, once you collect as much as you want, pour out of a cookie tray or something like that. Let it evaporate and then take that and heat it in pot till it turns red. Then if memory serves me right you will have iron Oxide.

Rick Goldman
- Bristolville, Ohio
2006

Hi, I have tried this. I was told that the wire that bubbles the most is the (+) positive, however it seems to be the negative that does this. is this ok?

D Howe
- England
2006

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You were misled, but your observation is correct. The negative lead releases hydrogen and there is twice as much hydrogen (by volume) as oxygen in water.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2006

The only problem with using salt water is you will also be electrolyzing the salt. As soon as the chlorine separates from from the sodium, the sodium will react with the water forming sodium hydroxide and chlorine gas. You will also get hydrogen. as for the iron nothing will happen to it, it might oxidize partially but for the most part it will be left alone.

Eric McCaughlin
- Dayton, Ohio
2006

Do I just put the positive and negative wires from the DC converter into the water or connect them to anything?

Matthew Hyde
- Pittsburgh, Pennsylvania
2007

No you take something you want to rust like two bolts for instance. Take the wires and rap them around the bolts individually. Then put the wires (with bolts raped on) into the water container.

Rick Reeves
- Hayfork, California
April 10, 2008

I've tried the DC converter method... it works. use a cheap train set power supply, connect wires from the power supply to iron nails... stick in some salt water and turn on. Don't let the wires touch the water or they'll oxidize too. it takes a while to turn the nails into rust, but it works well. you'll have to remove the excess water when you've run out of nails to rust... take the sludge and run it through a piece of cheesecloth or something to filter out the chunks of the nails that didn't rust. let it dry. careful... it's very hard to clean up if you make a mess.

John Smith
- New York, New York
May 2, 2008

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January 14, 2009

I have found a very easy way to make iron (III) oxide, Fe2O3.... from iron

Pour some hydrogen peroxide, 3% on to iron and it turns a nice reddish brown rust immediately on contact... wait for it to evaporate and you got some rust.. useful for things like thermite

Max Yevsyevyev
- Fremont, California

dude that will make hydrogen don't breathe it in.

Brian Wall
- st thomas, Ontario, Canada
March 24, 2010

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Building on the Hydrogen Peroxide (aka Peroxide or H2O2) method, you can use a DC power source such as a battery (9 Volt and 6 Volts work well) or a transformer (for a train or laptop) to speed up the Redox Reaction, just connect the wires to the nail or what ever you are using and keep them from touching, that way the circuit is completed through the H2O2. this is quick, hydrogen gas is produced, which you can keep and burn also. have fun.

Sam Kelemen
- Westlake, Ohio, USA
August 3, 2010

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Q. What kind of ratio is needed for the salt water?

Cameron White
- Grass Valley, California, USA
April 17, 2012