The recycling of carbon fiber reinforced plastics (CFRP: including 37wt% of matrix epoxy resin) using tetralin (hydrogen donor solvent), decalin (nondonor solvent), alcohols and light cycle oil (LCO) was carried out in a small autoclave at 350-440°C with a reaction time of 1h under 2MPa of initial nitrogen atmosphere. For the reaction using tetralin, decalin and alcohols, the gaseous product was small of 0.2-4wt%, while the gaseous product increased to 9.4wt% using LCO. Conversion of resin varied with reaction temperature and solvent. Conversion of resin by the use of tetralin at 440°C showed more than 95wt% and enough tensile strength of recovered monofilament was observed.
Similar high conversion and high grade quality of the recovered monofilament were also obtained by the use of cyclohexanol and other higher alcohols with sodium carbonate catalyst at 440°C. In these cases, phenol and alkylphenols were detected with 3.8-5.1wt%/CFRP (10.3-13.8wt%/resin) in the liquid product. This indicates that the degradation of thermosetting epoxy resin proceed effectively to produce monomer compounds with small gas production. However conversion of resin and tensile strength of the recovered monofilaments decreased at the lowering reaction temperature and the other solvent use.