Two words: Chlorine Triflouride!
It burn with such burnable stuff as:
- ash of a oxygen fire
- water (it explodes)
- 99% of all metals
- humans (not burns on them, but uses them as actuall fuel)
Indeed, it is hypergolic (spontaneous combustion at room temperature) with most of that stuff
It does not need a Oxygen Atmosphere. Compared to Flourine, Oxygen is a weak Oxygenation Agent. Oxygen deprivation does not kill this fire!
It was considered as:
- a Flamethrower fuel by Nazi German
- Rocket propellant component by NASA
For both it was too reactive, too dangerous.
Indeed, NASA once spilled a ton of the stuff:
- They could not extinguish it with water. Because a) fuel and b) explosive fuel
- they could not extinguish it with sand. Because a) fuel and b) Oxygen Deprivation does not bother it
- they could not use extinguishing foam or liquid of any kind. Because again: Oxygen Deprivation does not bother it
- they let it burn out. Through 30cm of concrete. And 90 cm of Gravel below the concrete.
I leave it to the Nasa report:
"It is, of course, extremely toxic, but that's the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water—with which it reacts explosively. It can be kept in some of the ordinary structural metals—steel, copper, aluminum, etc.—because of the formation of a thin film of insoluble metal fluoride that protects the bulk of the metal, just as the invisible coat of oxide on aluminum keeps it from burning up in the atmosphere. If, however, this coat is melted or scrubbed off, and has no chance to reform, the operator is confronted with the problem of coping with a metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes."