[thaefathan]

I work in a Sterile Processing department and we're having an argument about whether or not ethyl acetate corrodes the stainless steel or ruin's the finish on the instruments.  I've tried to look this up and I'm finding mixed things.  Can someone answer and explain how it works please?  thanks.

[Jesse2024]

Typical stainless steel contains a certain amount of chromium in the metal alloy, this in turn forms a thin layer of chromium oxide on the surface of the metal preventing further oxidation penetrating the metals structure.  A better question would be to ask if, assuming this is the type of stainless steel you have, whether ethyl acetate reacts with chromium oxide, of this I am not sure.

[DrCMS]

Ethyl acetate does not corrode stainless steel.

[Enthalpy]

Steel manufacturers have huge compatibility tables giving the corrosion resistance of various stainless compositions against many chemicals. This would be the definite answer.

I'm not too worried with an acetate, provided your steel is a usual austenitic one. Chlorine ions are the first big question instead.

Corrosion is more subtle than dissolving chromium oxide. There are indirect mechanisms letting mild acids like beer or pee corrode many stainless compositions.

[thaefathan]

Thanks for all the replys.
I looked on Cole-Parmer's website for the stainless steel 316 compatibility index with ethyl acetate, it gets a

B = Good -- Minor Effect, slight corrosion
or discoloration

Does anyone know the mechanism of corrosion?  Corrosion is oxidation right?  So does the metal, or Chromium oxide reduce the ethyl acetate?  I'm not coming up with much on google.
 Thanks

[Enthalpy]

The mechanism?
Metallurgy predicts nothing, but explains everything afterwards. Chemistry... And you want to combine both.
So if you want an explanation, you'll probably get some, like hydroxides building from oxides, or something like ethyl chromate. But will it serve to you?

For a sterile instrument, you don't want any visible effect of corrosion, do you? So that the user can see the instrument is clean. More, you don't want the instrument to release any dirt, for instance because 1/3 of women have allergic reactions to nickel.

So the operational answer would be: take a better steel. Maybe a Duplex, like 2205, or keep an austenitic one but with more chromium, maybe 36% Cr 18% Ni - I didn't check the tables.