Table 2.

Thermal recycling methods.

FRP	Reactor	Pyrolysis			Oxidation	Contribution	Ref.
		T (°C)	Time	Gas
CFR epoxy	Py-GC/MS 1	700	–	–	–	Study of two composite materials	[65]
CFR epoxy	TGA 2	900	Variable	N2 3	Air at 600 °C	Optimization of the pyrolysis cycle	[66]
CFR polybenzoxazine	Fixed-bed batch	350–700	1 h	N2	Air at 500 and 700 °C	Recovery of activated carbon fibers	[47]
CFR epoxy	Furnace	550	20 min 500 °C, 90 min 550 °C	N2	CO2 4 + O2 5 + air + H2O 6 at 550–700 °C	Chemical post-treatment in HNO3 7	[67]
CFR epoxy cured, uncured and contaminated	Batch furnace, commercial process	<400	Sample dependent	–	–	PPS 8 material (thermoplastic) with rCF	[68]
CFR polybenzoxazine	Pilot-scale facility	500–700	–	–	Gasification in air at 500 °C	Process optimization	[69]
CFR epoxy	Fixed bed reactor	550	30 min	H2O	Air at 550 °C for 30 to 75 min	Carbon fiber recovery by super-heated steam method	[70]
Cured and uncured epoxy CFR cuts	Pilot plant batch	500	150 min	N2	Air at 500–600 °C for 10 to 60 min	Recovery of recycled fibers and production of new composites	[71]
CFR epoxy	TGA	500–1000	Variable	N2/ CO2	–	Use of CO2 and water vapor to remove char	[72]
CFR epoxy	Furnace	360	80 min	Air	–	Carbon fibers recovery through catalytic pyrolysis in molten ZnCl2 9	[73]
CFR epoxy	Cone calorimeter (batch reactor)	550	20–25 min	–	–	Recovery of carbon fibers from discarded UD composites	[45]
CFR epoxy	TGA and furnace	300–700	60–120 min	N2	–	Process optimization	[74]

¹ Pyrolysis-gas chromatography and mass spectrometry; ² Thermogravimetric analysis; ³ Nitrogen; ⁴ Carbon dioxide; ⁵ Oxygen; ⁶ Water; ⁷ Nitric acid; ⁸ Polyphenylene sulphide; ⁹ Zinc chloride.