Fireplace Door Insulation

[alargroove]

I wanted to see if anyone knew the answer to this or not. I have a set of fireplace doors for my wood burning fireplace. After taking them to clean up I noticed the insulation inside of them. Most of it was ok, some of it is black possible burnt.

I would like to replace it. Is there a specific insulation I should use or Is it possible to replace with wool thermafiber Fire and Sound Guard
insulation( I have a bunch left over from a project)

Any help is apperiated.

 

[begreen]

Kaowool (ceramic wool) would be the safest. Whatever was used should never burn. Sooty maybe, but not burnt.