Flourine is electronegative enough to be able to burn with asbestos, but not willingly, it needs a lot of encouragement to do so. It'll happily burn spent coal

Flourine is electronegative enough to be able to burn with asbestos, but not willingly, it needs a lot of encouragement to do so. It'll happily burn spent coal or other oxygen burn byproducts. For asbestos you'll need some chlorine to make that flourine very excited about the idea of tearing apart some strong molecular bonds. Chlorinetriflouride is the candidate here, though Dioxygendiflouride also likes doing it, if in a more explosive fashion (it'll probably detonate in a hypergolic fashion with asbestos or sand).