condennnsa - 17-8-2010 at 23:55
Hey, maybe this is a noob question but i was wondering why metallic iron has such a strong smell, especially after washing a shiny piece thouroughly
with water...
I found mumbled references on the internet:
"The key component is called 1-octen-2-one, which smells fungal-metallic even when highly diluted. The precursors to the odor molecules are lipid
peroxides, which are produced when oils on skin are oxidized by certain enzymes or other processes (e.g. under UV light). These lipid ... "
But i really doubt that's true, for the only reason that even if you wear gloved hands, to sand a piece of iron, then wash it with lots of water to
get rid of all the powder, the smell remains.
So how come the Fe atoms go airborne all the way to my nose, provided iron doesn't just sublimate, or maybe it does... ? thanks!
bahamuth - 18-8-2010 at 11:37
A little off topic but a similar smell may be experienced when filing aluminum, magnesium and carburetor(believe it is zinc) alloys.
Might be arsenic, phosphorus or sulfur impurities reacting catalytic with air/moisture when fresh metal is exposed. Just a speculation from my side,
really do not know but I confirm you findings as I have done a lot of metalwork (had a blacksmithing hobby a couple years back).
Nicodem - 18-8-2010 at 13:52
http://www.sciencemadness.org/talk/viewthread.php?tid=5679
12AX7 - 18-8-2010 at 22:00
Octenone.
When dissolving alloys in acid (including iron and aluminum), assorted sulfur and phosphorus compounds are released. Apparently, the phosphorus
compounds are much smellier than plain old phosphine and diphosphine (which are also pyrophoric); the reason is they contain organic molecules, I
suppose as a result of bonds inside the metal (perhaps P and C atoms occupying adjecent interstices in the metal). Add water, and the bonds become
hydrated (and hydrogenated).
Steel is very interesting stuff... supposedly, the famous wootz steel contains nanotubes and branched buckyballs, in addition to traditional cementite
and microstructural features.
Tim