This looks like recycling fetishism. It's perfectly fine to burn such materials, if they were obtained from non-fossil sources to start with, so there would be no net CO2 addition to the atmosphere.

An adjacent design validation question on a green chip factory and product design:

Will Phytic acid in Lignin-Vitrimer encase burning CNT carbon nanotubes in a phosphorous char cage, this preventing health hazards and combustion?

This says "phosphorous epoxy".

FR4 silicon PCBs are N-doped and P-doped.