An environmental and economic study on the chemical recycling of plastic composites using an engineering constitutive...

Carbon fiber-reinforced polymer composites are widely used in engineering applications due to their exceptional thermal and mechanical properties. Recently developed chemical recycling techniques offer a sustainable solution for recycling these materials, which use organic solvents to depolymerize the composite matrix under mild conditions. However, existing analyses of the environmental impacts and economic viability of composite recycling often rely on rough estimations for input and output data, which significantly limit their predictive accuracy. This study introduces a novel approach by integrating an engineering constitutive model with lifecycle and cost analyses to provide more precise assessments under varying processing conditions. By comparing landfill disposal, mechanical recycling, pyrolysis, solvolysis, and chemical recycling, the study highlights the distinct environmental and economic characteristics of each method. The findings indicate that solvent-assisted chemical recycling offers superior net environmental savings while maintaining low energy consumption, capital investment, and recycling costs. The adoption of the engineering constitutive model also enables parametric analysis and optimization of processing conditions. It shows that by reducing catalyst content and lowering temperature, chemical recycling can reduce costs by over 58 % and improve the benefit-cost ratio by 24.4 % without compromising environmental benefits. Overall, this study provides valuable recommendations for refining recycling processes with a focus on sustainability, while also supporting more informed decision-making aligned with sustainable development principles.