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Bio rusting

I heard someone theorizing that the normal rusting process of iron might depend on bacterial action. If bacteria are not present, will iron rust extremely slowly? It shouldn't be too hard to see if this is true. Get two glass jars and two iron nails. Clean the iron with sandpaper to get rid of any oily coating. Fill the jars with distilled water. Drop in the iron. One jar should have normal bacteria from the environment, so add a small bit of dirt. Put a tiny bit of powerful bactericide in the other jar. (Or sterilize it in the same way you do "canning" at home) Wait a few days, and see if one piece of iron obviously rusts more than the other. What kind of bactericide to use? I dunno, maybe anti-bacterial hand soap. Better put some normal soap in the other jar as a control, since I don't know if soap affects rusting too. Nobody has tried this project yet, as far as I know. If it doesn't work, it still is interesting: it tells you that bacteria doesn't accelerate rusting. Search for: IRON BACTERIA, IRON-LOVING BACTERIA, IRON-EATING BACTERIA, NANNOBACTERIA, HYPERTHERMOPHILES.

Michael M.
- Garfield, Washington
2005

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2005

Please do the experiment and let us know the results. However, use dish detergent rather than hand soap (to avoid oily moisturizers).

Microbiologically Influenced Corrosion (MIC) has been known for a long time � see corrosion books. It is not considered the "normal" form of rusting. Some microbes also require sulfur, present in low concentrations in steel, combustion deposits or naturally occurring metal sulfides. Microbes are used beneficially in leaching metals from low-grade ores.

"Not all corrosion is MIC. Resolving, understanding and mitigating MIC problems require familiarity with all four fields: microbiology, metallurgy, electrochemistry and water chemistry." from
Microbiologically Influenced Corrosion Handbook by Susan Watkins Borenstein, 288 pages, ISBN: 0831130563 (1994). About $51.

Another good reference is
Microbial Iron Metabolism: A Comprehensive Treatise by J. B. Neilands, 597 pages, ISBN: 0125152507 (1974). About $20.

Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.

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2005

A free sample chapter "Biological Corrosion Failures," from
ASM Handbook Volume 11: Failure Analysis and Prevention, ISBN 0871707047 (2002), is available on-line at
www.asminternational.org

Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.

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2006

Hi
If you want to understand more about how the bacteria increases the velocity of corrosion , you need to study about the importance of dissolved oxygen in water.
In steel industry the waste water is used sometimes to cool the steel plates in the mills this kind of water contains bacterias that need oxygen to live, then if they steal the oxygen of water, then the dissolved oxygen decreases , then the water becomes in like "acid" and corrosion is growing up.
you can read more in NALCO books.

ISRAEL GARCIA
- FORT WAYNE, INDIANA, USA

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I am in 9th grade. I just wanted to know whether bacteria affected the rate at which iron can rust. I wanted to do an experiment on these by putting one iron nail in a container of distilled water with some natural bacteria and another in a container w/ distilled water and bactericide(anti-bacterial soap?)and checking back on them daily.

thanks

Ambreen M
student - Chicago, Illinois, USA
2006 --appended to this thread by editor

My name is Yusra and I am in 8th grade. I tried that bio rusting experiment because it seemed interesting. the nails have some sort of yellow-orange blotches on them. what is that?

Yusra M
student - Chicago, Illinois, USA
2006

I'm testing this myself for science fair. I couldn't find anything else ^o^

Mike T.
- Sterling, Virginia
2006

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I performed the experiment you suggested.after 24 hrs I found much rusting in autoclaved distilled water than in tap water. The color of rusting in both the jars were different.autoclaved distilled water contained dark reddish color rust and the other faint orange color.
Please suggest further to investigate the microbes responsible for rusting of iron .

Premit Chopra
- Ahmednagar, India
2006

I'm in 7th grade, and I also did this project because it seemed interesting, except I used normal soap instead of hand soap. The results were quite similar when I used hand soap as experimental. the iron nail in the distilled water had wierd blotches on it though...

Wenlan Z. [last name deleted for privacy by Editor]
- New York, USA
2006

I did this project for science fair and found that the process in some things may be chemical and not biological.

Christina Charlotte C. [last name deleted for privacy by Editor]
student - Aurora, Colorado, US
2007

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January 19, 2008

Hi!

I am in 8th grade and I desperately need help on finding information on a science project I am doing. My question is "How will various organic bacteria affect the growth of rust?"
I want to find some sources to rust and bacteria, but I can't. Please help me. Thank you.

Lydia M. [last name deleted for privacy by Editor]
student - Miami, Florida, United States