Recycling of Carbon Fiber Reinforced Plastic with Supercritical Ethanol in the Presence of Sn, Cu, Co Salts

The widespread demand for polymer composites in various branches of mechanical engineering has led to an increased need for these materials. However, the issues of recycling of these materials, especially materials based on thermosetting matrices, have not been properly studied due to their long operating cycles. Additionally, traditional methods of recycling cannot be applied to polymer composite materials (PCMs) while preserving the properties of the filler. At the end of its service life, the carbon fiber reinforced plastic still contains filler. The reuse of this filler in the production cycle can significantly reduce manufacturing costs. This study focuses on the recycling process of PCMs based on carbon fiber and epoxy binder using supercritical ethanol as the medium. Solvolysis was conducted in a high-pressure reactor equipped with a 25 ml fluoroplastic liner. The solvolysis, performed at 250 °C. Salts of various metals were used as catalysts. In some experimental series, cleaned carbon fibers were successfully obtained, which were subsequently returned in the production of new polymer composite materials. The investigation into the strength of carbon fiber plastics revealed that materials derived from recovered fibers maintained their properties. Moreover, through processing in a supercritical ethanol environment with the presence of SnCl₂, there was a 5% increase in bending strength. This finding highlights the potential for enhancing the mechanical properties of recycled polymer composites, contributing to both sustainability and cost-effectiveness in the production cycle.