question for metallurgists (re:stainless steel and toxic binding)

[BuzzCraft]

Can stainless steel harbor toxic chemicals and the like, if it has been exposed to such?

I've been on the lookout for a large stainless steel sink for a mash tun and have finally located one. It is an old sink and was employed in a biochemistry lab in a previous life, so who knows what it has been exposed to. Thus the question.

Thanks for any insight you can provide.

 

[mosquitocontrol]

Stainless steel being corrosion resistant works on the principal that it forms an oxide scale on the surface. I'd imagine this is where parts of toxic chemicals could react and stay on the surface. But to be honest I'm not sure. If you could remove the top layer (the oxide) and start from scratch you should be fine though.

I'm not a very good metallurgist I guess..

 

[jds]

Metallurgist checking in here.

My main concern with re-using old stainless equipment is the difficulty in getting crevices and corners really clean. If a stainless container was used for solvents or inorganic acids, I wouldn't worry about it very much. If it was used for storage of really nasty stuff (carcinogens like PCB's) then I'd avoid it.

If you have a nice, clean stainless container, and some time, a good abrasive polishing of the surface followed by repassivating the stainless with barkeeper's friend should render it as good as new, especially if you don't have inconvienent welds or crevices to deal with.

For a sink, I'd pull all the drain fittings off, and go at it with a scotch-brite pad, followed by BKF. There shouldn't be anything too nasty in a lab sink, since the really hazardous stuff is RCRA controlled and has to be disposed of somewhere else than into the sewer.

 

[BuzzCraft]

Thanks a lot for the replies. That's very useful and reassuring information, jds. This sink has easily cleaned contours at the corners, so i should be able to clean it up well after removing the drain.

Thanks again.