Why does tannic acid remove rust from iron parts?

I am doing a chemistry project on corrosion removal. I used tannic acid to remove some of the rust from iron parts and it worked. But here’s the thing, I need to find out why this happened. If someone could answer this and state where they got their info from, it would be appreciated….thx!♥

Tannins are high in the polyphenols which can easily be oxidized to the corresponding polyquiniones.

hence allowing for

2Fe2O3 –> 4Fe + 3O2

1/2 reaction being:

Fe+3 + 3e- –> Fe

OH-Ar-OH –> O=C(C=C)2-(6memring)C=O + 2H+ 2e-

This entry was posted on Wednesday, March 31st, 2010 at 4:33 am and is filed under corrosion removal. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

2 Responses to “Why does tannic acid remove rust from iron parts?”

Alf G on March 31st, 2010 at 9:50 am

Rust = Iron oxide.

The acid reacts with the oxide to produce soluble salts and therefore removes the rust
References :
Dr Dave P on March 31st, 2010 at 10:27 am

Tannins are high in the polyphenols which can easily be oxidized to the corresponding polyquiniones.

hence allowing for

2Fe2O3 –> 4Fe + 3O2

1/2 reaction being:

Fe+3 + 3e- –> Fe

OH-Ar-OH –> O=C(C=C)2-(6memring)C=O + 2H+ 2e-
References :

Rust