I have not encountered this fine substance myself, but reading up on its properties immediately gives it a spot on my “no way, no how” list. Let's put it this way: during World War II, the Germans were very interested in using it in self-igniting flamethrowers, but found it too nasty to work with. It is apparently about the most vigorous fluorinating agent known, and is much more difficult to handle than fluorine gas. That’s one of those statements you don’t get to hear very often, and it should be enough to make any sensible chemist turn around smartly and head down the hall in the other direction.
The compound also a stronger oxidizing agent than oxygen itself, which also puts it into rare territory. That means that it can potentially go on to “burn” things that you would normally consider already burnt to hell and gone, and a practical consequence of that is that it’ll start roaring reactions with things like bricks and asbestos tile. It’s been used in the semiconductor industry to clean oxides off of surfaces, at which activity it no doubt excels.
There’s a report from the early 1950s (in this PDF) of a one-ton spill of the stuff. It burned its way through a foot of concrete floor and chewed up another meter of sand and gravel beneath, completing a day that I'm sure no one involved ever forgot. That process, I should add, would necessarily have been accompanied by copious amounts of horribly toxic and corrosive by-products: it’s bad enough when your reagent ignites wet sand, but the clouds of hot hydrofluoric acid are your special door prize if you’re foolhardy enough to hang around and watch the fireworks.When I was in junior high, I still fantasized about being a research chemist. (Those weren't your junior high fantasies? Okay, I'm weird.) I remember being quite fascinated with what I read about fluorine gas and its unique properties. Fluorine gas doesn't just set fire to water (it rips the water molecule apart so that you now have free oxygen atoms running around frantically to find something to burn), it burns even substances that we don't think of as burnable--and even makes asbestos glow.
The Greeks were convinced that there were four elements (earth, air, fire, and water) that, mixed in the appropriate proportions, made up everything. Fluorine gas seems perilously close to the essence of fire!
I've read that most of the nineteenth century chemists who tried to isolate fluorine gas died fairly young, because fluorine compounds tend to be pretty poisonous--even if you aren't catching on fire. The scientist who finally isolated fluorine gas was Henri Moissan, who lived to a ripe old age for a chemist--and especially a fluorine chemist.
My recollection was that he was able to electrolytically separate fluorine from the compounds to which it clings with great vigor without dying by the following steps:
1. Most of the reaction vessels were carved out of single pieces of fluorospar, a calcium fluoride mineral. The calcium in fluorospar already has all the fluorine atoms it can use, so it's like a traditional junior high dance with thirty girls and five boys--there's no way for more than five girls at a time to dance. The girls sitting on the sidelines might be able to cut in, but the number of girls sitting on the sidelines, worried that they don't look good enough, doesn't change.
2. Most of the rest of the piping was made of copper, which reacts vigorously with fluorine gas, but once the reaction is complete, it produces a very tight, very durable coating of copper fluoride that doesn't react anymore. (This is analogous to how aluminum rapidly forms an aluminum oxide coating that protects the surface from further oxidation.)
3. The whole apparatus was cooled down to -50 degrees Celsius, at which point fluorine only reacts like the cartoon version of a Tasmanian devil.
Fluorine: Satan's element!
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