Carbon Fiber Reinforced Polymers Waste Research Articles

Upcycling end-of-life carbon fiber in high-performance CFRP composites by the material extrusion additive manufacturing process

Each year, a significant amount of waste is produced from carbon fiber polymer composites at the end of its lifecycle due to extensive use across various applications. Utilizing regenerative carbon fiber as a feedstock material offers a promising and sustainable approach to additive manufacturing based on materials. This study proposes the additive manufacturing of recycled carbon fiber with a polyamide-12 polymer composite. Filaments of recycled carbon fiber-reinforced polyamide-12 (rCF-PA12) with different recycled carbon fiber contents (0%, 10%, and 15% by weight) in the polyamide-12 matrix are developed. These filaments are utilized for 3D printing of specimens by using various infill density parameters (80% and 100%) on a fused deposition modeling 3D printer. The study examined how the fiber content and infill densities influenced the flexural performance of the printed specimens. Notably, the part containing 15 wt% recycled carbon fiber (rCF) composites showed a significant improvement in flexural performance due to enhanced interface bonding and effective fiber alignment. The results indicated that reinforcing the printed part with 10% and 15 wt% recycled carbon fiber (rCF) improved the flexural properties by 49.86% and 91.75%, respectively, compared to the unreinforced printed part under the same infill density and printing parameters. The investigation demonstrates that the additive manufacturing-based technique presents a potential approach to use carbon fiber-reinforced polymers waste and manufacture high-performance engineering, economic, and environmentally friendly industrial applications with the complicated design using different polymer matrices.

Study on recycling carbon fibers from carbon fiber reinforced polymer waste by microwave molten salt pyrolysis

The extensive application of carbon fiber reinforced polymers (CFRP) has led to a sharp rise in the waste generated from CFRP, which poses a significant issue in sustainability that needs to be addressed. This work presents an efficient treatment method to recycle CFRP waste. Under the combined action of microwave heating and ZnCl2/NaCl molten salt, the epoxy resin matrix was rapidly degraded at 300 ℃ in 20 min. Then the pyrolytic carbon produced on the surface of carbon fibers from this process was removed by oxidation procedure in an air atmosphere. The results showed that the surface morphology and microstructure of the recycled carbon fibers (RCF) had no obvious changes, and the tensile strength and tensile modulus of RCF remained at 87.8 % and 94.6 % of the virgin carbon fibers, respectively. The degradation of epoxy resin by microwave molten salt pyrolysis increased the output of H2, which reached 65.35 % of total pyrolysis gases. Furthermore, the epoxy resin can be transformed directionally. The main components of the pyrolysis oils were phenol and p-isopropyl phenol, which had a high utilization value. Therefore, this study designed a new and efficient process to recycle carbon fibers from CFRP waste, which has important application prospect.

Reusing Bisphenol—A Type of Epoxy Polymer Recyclates from the Solvolysis of CFRP

Carbon fiber-reinforced polymer (CFRP) composites are highly functional composites which comprise two major components: the polymer matrix and the carbon fiber. Lightweight and having high strength, CFRPs have been used heavily in various industries such as wind, aerospace and automobile. The increasing demand and extensive use led to a huge quantum of CFRP waste from both end-of-life and during manufacturing. Out of this waste, only 2% is recycled, the rest are disposed of via incineration and/or landfill. This has raised significant environmental and sustainability concerns. The current state-of-the-art way of recycling CFRPs is by pyrolysis. However, through the pyrolysis process, the polymer used in the CFRPs, which accounts for around 65–75 wt.%, cannot be recovered and reused. In most publications, the focus on CFRP recycling was on the recovering of the more valuable carbon fiber. The polymer matrix is mostly burnt off, in the case of pyrolysis, or disposed. To obtain full circularity, recovering and reusing both the carbon fiber and polymer is necessary. In this paper, we primarily focus on the recovered bisphenol-A type of epoxy polymer (REP) obtained from solvolysis digestion of CFRP and explore the feasibility of reusing this REP by blending it with pristine epoxy in various compositions to create new materials. The physical and mechanical properties, including decomposition temperatures (Td), glass transition temperatures (Tg), storage modulus, loss modulus, flexural and tensile strength, were characterized using thermal gravity analyzer (TGA), differential scanning calorimetry (DSC), dynamic mechanical analyzer (DMA) and Instron universal tester. The results indicate a decrease in glass transition and decomposition temperature, and mechanical properties as the blending composition increases. This suggests that the total blending composition should not exceed 10 wt.%, with an optimal range potentially falling between 5 to 6 wt.%.

Recycling Carbon Fiber from Carbon Fiber-Reinforced Polymer and Its Reuse in Photocatalysis: A Review.

Driven by various environmental and economic factors, it is emerging to adopt an efficient and sustainable strategy to recycle carbon fibers (rCFs) from carbon fiber-reinforced polymer (CFRP) wastes and reuse them in high-value applications. This review summarized the latest progress of CFRP waste recycling methods (including mechanical, chemical, and thermal methods), discussed their advantages and disadvantages, influence parameters and possible environmental effects, and their potential effects on the mechanical and surface chemical properties of rCFs. In addition, the latest optimization schemes of leading recycling technologies were detailed. According to the literature, CFs are the key points in the structural support of semiconductor-based recyclable photocatalytic systems and the enhancement of performance, which means that rCFs have high reuse potential in sustainable photocatalysis. Therefore, this paper also emphasized the possibility and potential value of reusing recovered fibers for developing recyclable photocatalytic products, which may be a new way of reuse in environmental purification often ignored by researchers and decision-makers in the field of CFs.

Recovery of carbon fiber-reinforced polymer waste using dimethylacetamide base on the resin swelling principle.

The mechanical recycling method of the carbon fiber-reinforced polymer (CFRP) has the advantages of simple process, less pollution and low cost, but only low utilization value of carbon fibers in powder or short fibers form can be obtained. To reduce the length and strength loss of the recycled carbon fibers, a novel and cost-effective dimethylacetamide (DMAC) swelling technique was developed to achieve rapid delamination of the CFRP laminates under mild conditions (120°C-160°C, 1h). The corresponding swelling ratios and mass-loss rates of cured epoxy resin (CEP) were about 121.39%-157.39% and 0-0.69%, respectively. Excessive swelling of CEP in DMAC resulted in the cracking of the resin matrix between the adjacent carbon fiber layers. Thus the CFRP laminates were delaminated into soft single carbon fiber layers, which showed excellent cutting performance and reinforcing properties. The delamination products were cut into thin strips of different sizes and vacuum bag molded into new CFRP laminates. The flexural strength and tensile strength of the newly produced CFRP laminates were about 76.38%-90.98% and 94.61%-98.54% of the original CFRP laminates, respectively. More importantly, the chemical compositions of DMAC and CEP were unchanged during the physical swelling process. No organic pollutants (caused by resin degradation) were generated. And the used DMAC can be easily recycled by filtration. Therefore, this study provides a strategy for low-cost and high-valued recycling of CFRP waste.

A closed-loop recycling process for carbon fiber-reinforced polymer waste using thermally activated oxide semiconductors: Carbon fiber recycling, characterization and life cycle assessment

The objective of this study is to investigate the properties of recycled carbon fiber (rCF) and its environmental impact, with a specific focus on the energy consumption of the recycling process based on the use of thermally activated oxide semiconductors (TASC). The mechanical and surface properties of rCF obtained under the optimal process parameters were characterized. The life cycle assessment method was used to evaluate the environmental impact of a closed-loop recycling process for carbon fiber-reinforced polymer (CFRP) waste using TASC. The results indicated that the decomposition rate of resin was 95.5 %, and no carbonaceous solid was generated. The gaseous produced of the recycling process were mainly CO2 and H2O, and no liquid products were produced. The surface oxidation degree of rCF was relatively slight. COOH was generated on the surface of rCF, which was conducive to improving the interfacial adhesion viscosity with resin. The monofilament tensile strength of rCF was maintained above 97 %. Compared with landfill and incineration, CFRP waste recycling using TASC can make global warming potential, acidification potential and eutrophication potential reduced by 28 %, 32 %, and 25 %, respectively. Ozone layer depletion potential, human toxicity potential and terrestrial ecotoxicity potential in disposing CFRP waste using TASC were 30 %, 21 % and 41 % of that using pyrolysis, respectively. The energy consumption in carbon fiber recycling by TASC was only 23 % of that in virgin carbon fiber manufacturing. TASC is found to be a promising potential strategy for managing CFRP waste.

Economic and energy benefit of a method for treating the vapors coming from the recycling of carbon fiber waste by pyrolysis

The growing utilization of carbon fiber reinforced polymers (CFRP) in industry involves the generation of high quantities of this kind of waste. This tendency has fomented the investigation of different alternatives to recycle CFRP waste with the aim of reclaiming the carbon fibers, a material with high specific economic value. Among the alternatives, pyrolysis is the only one runnig at commercial scale nowadays. This process consists on heating the waste in an inert or oxygen-poor atmosphere, which causes the decomposition of the polymeric resin of the material and consequently the reclamation of the carbon fibers. The resin decomposes into organic vapors, which are normally incinerated and released to the atmosphere. The objective of this paper is to present the economic and energy benefit of a method for treating the vapors coming from the resin decomposition, through which high value chemicals can be obtained, avoiding the vapors incineration and emission. By means of this recently patented method a gas fraction with a higher energetic content than that of the vapors without treatment can be obtained. Besides, this gaseous fraction contains high quantities of hydrogen, which could be separated and sold. The commercialization of this hydrogen could increase 6 times the economic value of the gaseous fraction compared to the gas fraction without treatment.

Recent Progress in Carbon Fiber Reinforced Polymers Recycling: A Review of Recycling Methods and Reuse of Carbon Fibers.

The rapid increase in the application of carbon fiber reinforced polymer (CFRP) composite materials represents a challenge to waste recycling. The circular economy approach coupled with the possibility of recovering carbon fibers from CFRP waste with similar properties to virgin carbon fibers at a much lower cost and with lower energy consumption motivate the study of CFRP recycling. Mechanical recycling methods allow the obtention of chopped composite materials, while both thermal and chemical recycling methods aim towards recovering carbon fibers. This review examines the three main recycling methods, their processes, and particularities, as well as the reuse of recycled carbon fibers in the manufacture of new composite materials.

Undergraduate Research Program to Recycle Composite Waste

With the rapid growth in the manufacturing industry and increased urbanization, higher amounts of composite material waste are being produced, causing severe threats to the environment. These environmental concerns, coupled with the fact that undergraduate students typically have minimal experience in research, have initiated the need at the UAE University to promote research among undergraduate students, leading to the development of a summer undergraduate research program. In this study, a recycling methodology is presented to test lab-fabricated Carbon-Fiber-Reinforced Polymer (CFRP) for potential applications in industrial composite waste. The work was conducted by two groups of undergraduate students at the UAE University. The methodology involved the chemical dissolution of the composite waste, followed by compression molding and adequate heat treatment for rapid curing of CFRP. Subsequently, the CFRP samples were divided into three groups based on their geometrical distinctions. The mechanical properties (i.e., modulus of elasticity and compressive strength) were determined through material testing, and the results were then compared with steel for prompt reference. The results revealed that the values of mechanical properties range from 2 to 4.3 GPa for the modulus of elasticity and from 203.7 to 301.5 MPa for the compressive strength. These values are considered competitive and optimal, and as such, carbon fiber waste can be used as an alternate material for various structural applications. The inconsistencies in the values are due to discrepancies in the procedure as a result of the lack of specialized equipment for handling CFRP waste material. The study concluded that the properties of CFRP composite prepreg scrap tend to be reusable instead of disposable. Despite the meager experimental discrepancies, test values and mechanical properties indicate that CFRP composite can be successfully used as a material for nonstructural applications.

Life cycle assessment and energy intensity of CFRP recycling using supercritical N-butanol

Recycling carbon fiber reinforced polymer (CFRP) waste is unavoidable for the sustainable manufacturing and cost reduction of CFRP products. Supercritical fluid technology is an emerging chemical method for recycling CFRP waste, but its energy intensity and environmental implication are limited understanding. In this paper, the energy intensity and environmental impact of supercritical fluid technology were quantitatively assessed in CFRP recycling process. Then, the life cycle assessment (LCA) method was used to analyse the life cycle environmental impact of CFRP in two scenarios, scenario (a) using conventional waste disposal method, while scenario (b) with CFRP waste recycling process. The results show that the energy consumption of CFRP waste recycling is 49.21 MJ/kg using the supercritical n-butanol method, which is far lower than that of virgin carbon fiber production (286 MJ/kg). Scenario (b) with CFRP waste recycling has a lower impact than scenario (a) at nine environmental impact categories, including a 26% reduction of global warming potential. Besides, the energy consumption of the supercritical n-butanol method is 31% lower than that of the steam thermolysis method (71.64 MJ/kg) in recycling 1 kg of CFRP waste, which validates that the supercritical n-butanol method is a potential strategy for recycling CFRP waste.

Integrating carbon fiber reclamation and additive manufacturing for recycling CFRP waste

There is a large amount of carbon fiber reinforced polymer (CFRP) waste generated annually, mainly due to the difficulty in recycling CFRPs. This work presents a novel additive manufacturing-based recycling approach that can be used to reclaim CFRP waste and to re-manufacture the carbon fiber into 3D printed composite parts. A trial of this idea was set up, in which carbon fiber was first reclaimed from CFRP waste using supercritical fluid and then mixed with Poly-Ether-Ether-Ketone to produce composite filaments. The filaments were then fed into a printer of fused deposition modeling (i.e., a 3D printing process) and the recycled CFRP parts were fabricated. The engineering application-oriented tests demonstrate that the reclaimed carbon fiber can modify the performances of 3D printed part effectively in terms of mechanical strength, electrical conductivity, heat conduction and wear resistance. This work illustrates that the additive manufacturing-based recycling approach offers a possible strategy to recycle CFRP waste and fabricate high-performance engineering parts with complex geometries, which are economical and environmentally friendly.

Efficient recycling of carbon fibers from amine-cured CFRP composites under facile condition

With an excellent combination of high strength, lightweight, and thermal stability, carbon fiber-reinforced polymer (CFRP) composites are ideal for applications in various demanding fields. The global consumption of CFRP composites continues to increase, and it is estimated that approximately 3000 tonnes of CFRP waste are generated annually. Mostly, the CFRP composites can be classified into two categories: thermoset composites and thermoplastic composites. However, the recycling of industrial thermoset composites is a daunting challenge due to their highly cross-linked thermosetting polymer matrix. In this study, an innovative strategy was developed for recycling amine-cured CFRP composites with a binary alkali catalytic system of monoethanolamine containing 10 wt% potassium hydroxide under facile conditions. The degradation ratio of CFRP composites reached 98.82% after processing at 160 °C in 90 min. The surface of recovered carbon fibers (CFs), as observed by SEM and AFM, appeared smooth, and there was a slight increase in the surface wettability as tested by dynamic contact angle measurements. Furthermore, the use of XPS demonstrated some surface oxidation, while single fiber filament testing suggests a small decrease in the tensile strength of 6.5%.

An additive manufacturing-based approach for carbon fiber reinforced polymer recycling

The vast Carbon Fiber Reinforced Polymer (CFRP) waste accumulated is pressing for its recycling. A novel recycling approach, which integrated carbon fiber reclamation and composite additive manufacturing, is proposed to process the CFRP waste into three Dimensional (3D) parts. In the experiments, the CFRP waste was recycled by supercritical n-butanol to yield reclaimed Carbon Fibers (rCFs). The rCFs were ground by a ball mill, mixed with Poly-Ether-Ether-Ketone (PEEK) powder and then extruded to the composite filament. The filament was fed to the Fused Deposition Modeling (FDM) printer to fabricate 3D parts. Mechanical and electrical properties of the parts were investigated and compared with that of pure PEEK. The results illustrate that the additive manufacturing-based approach offers a potential strategy to reuse the CFRP waste and rapidly fabricate the rCF reinforced plastics with complex geometry and function.

Recycling of Carbon Fibers from CFRP Waste by Microwave Thermolysis

With the growth of the use of carbon fiber-reinforced polymer (CFRP) in various fields, the recovery of carbon fibers from CFRP waste is becoming a significant research direction. In the present work, degrading epoxy resin and recycling carbon fibers from CFRP waste by microwave thermolysis and traditional thermolysis were studied. The carbon fibers were successfully recovered by thermolysis under an oxygen atmosphere in this study. The properties of the recovered carbon fibers were characterized by field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and Raman spectroscopy. The result shows that using microwave thermolysis to recover carbon fibers from CFRP waste is an attractive prospect. Compared to the traditional method, the reaction time was reduced by 56.67%, and the recovery ratio was increased by 15%. Microwave thermolysis is faster, more efficient, requires less energy, and obtains cleaner recovered carbon fibers than those recovered using traditional thermolysis.

Review on: Multi - Objective optimization of Composite Automobile over Drive Shaft

Composites is increasingly used in different applications in the last decade, especially in aerospace due to their high strength and lightweight characteristics. Indeed, the latest models of Airbus (A350) and Boeing (B787) have employed more than 50 wt% of composites, mainly Carbon Fiber Reinforced Polymers (CFRP). Yet, the increased use of CFRP has raised the environmental concerns about their end-of-life related to waste disposal, consumption of non-renewable resources for manufacturing and the need to recycle CFRP wastes. In this study, generic model is developed in order to propose an optimal management of aerospace CFRP wastes taking into account economic and environmental objectives. Initially, a life-cycle systemic approach is used to model the environmental impacts of CFRP recycling processes focusing on Global Warming Potential (GWP) following the guidelines of Life Cycle Assessment (LCA). The whole supply chain for recycling CFRP pathways is then modeled from aircraft dismantling sites to the reuse of recycled fibers in various applications. A multiobjective optimization strategy based on mathematical programming, ε-constraint and lexicographic methods with appropriate decision-making techniques (M-TOPSIS, PROMETHEE-GAIA) has been developed to determine CFRP waste supply chain configurations. Different scenarios have been studied in order to take account the potential of existing recycling sites in a mono-period visions as well as the deployment of new sites in a multi-period approach considering the case study of France for illustration purpose. The solutions obtained from optimization process allow developing optimal strategies for the implementation of CFRP recovery with recycled fibers (of acceptable quality) for the targeted substitution use while minimizing cost /maximizing profit for an economic criterion and minimizing an environmental impact based on GWP.

Sustainability assessment of solvolysis using supercritical fluids for carbon fiber reinforced polymers waste management

This research aims to quantify cradle-to-gate (C2G) energy intensities, environmental, and human health burdens associated with production of one functional unit (FU) of 17 candidate supercritical fluids (SCFs) commonly proposed for depolymerizing thermoset resins contained in carbon fiber reinforced polymer (CFRP) waste. The environmental and human health burdens are calculated using TRACI 2.1 methodology. Seventeen Aspen HYSYS simulation cases and their associated GaBi product system models are developed and used to quantify energy intensities and mid-point impact categories associated with C2G production of these SCFs. A numerical example is provided to demonstrate that increasing solvolysis reaction temperature and pressure to improve thermoset resin removal efficiency also leads to SCF production energy penalty and associated increase of environmental footprint and human health burdens. The quantification results show that supercritical (SC) 1-propanol has the highest C2G production energy intensity (68.68–69.45 MJ/kg) followed by SC acetone (65.29–66.80 MJ/kg). Supercritical water (SCW) has the lowest C2G production energy intensity (9.5 MJ/kg) and lowest environmental footprint. Supercritical binary mixtures of pure solvents and water are not only more effective in reclaiming CF from CFRP waste, but also have lower C2G production energy intensities and cause lesser environmental and human health burdens compared to use of only pure solvent in their SC states. One of the core insights of this sustainability assessment highlights the need for discovering greener SCFs compared to the currently proposed ones in order to close the CFRP life cycle loop in a sustainable manner.

Comparative environmental and human health evaluations of thermolysis and solvolysis recycling technologies of carbon fiber reinforced polymer waste

This quantitative research aims to compare environmental and human health impacts associated with two recycling technologies of CFRP waste. The ‘baseline’ recycling technology is the conventional thermolysis process via pyrolysis and the ‘alternative’ recycling technology is an emerging chemical treatment via solvolysis using supercritical water (SCW) to digest the thermoset matrix. Two Gate-to-Gate recycling models are developed using GaBi LCA platform. The selected functional unit (FU) is 1 kg CFRP waste and the geographical boundary of this comparative LCIA is defined to be within the U.S. The results of this comparative assessment brought to light new insights about the environmental and human health impacts of CFRP waste recycling via solvolysis using SCW and, therefore, helped close a gap in the current state of knowledge about sustainability of SCW-based solvolysis as compared to pyrolysis. Two research questions are posed to identify whether solvolysis recycling offers more environmental and human health gains relative to the conventional pyrolysis recycling. These research questions lay the basis for formulating two null hypotheses (H0,1 and H0,2) and their associated research hypotheses (H1,1 and H1,2). LCIA results interpretation included ‘base case’ scenarios, ‘sensitivity studies,’ and ‘scenarios analysis.’ The results revealed that: (a) recycling via solvolysis using SCW exhibits no gains in environmental and human health impacts relative to those impacts associated with recycling via pyrolysis and (b) use of natural gas in lieu of electricity for pyrolyzer’s heating reduces the environmental and human health impacts by 37% (lowest) and up to 95.7% (highest). It is recommended that on-going experimental efforts that focus only on identifying the best solvent for solvolysis-based recycling should also consider quantification of the energy intensity as well as environmental and human health impacts of the proposed solvents.

Life cycle assessment of a steam thermolysis process to recover carbon fibers from carbon fiber-reinforced polymer waste

Carbon fibers have been widely used in composite materials, such as carbon fiber-reinforced polymer (CFRP). Therefore, a considerable amount of CFRP waste has been generated. Different recycling technologies have been proposed to treat the CFRP waste and recover carbon fibers for reuse in other applications. This study aims to perform a life cycle assessment (LCA) to evaluate the environmental impacts of recycling carbon fibers from CFRP waste by steam thermolysis, which is a recycling process developed in France. The LCA is performed by comparing a scenario where the CFRP waste is recycled by steam-thermolysis with other where the CFRP waste is directly disposed in landfill and incineration. The functional unit set for this study is 2 kg of composite. The inventory analysis is established for the different phases of the two scenarios considered in the study, such as the manufacturing phase, the recycling phase, and the end-of-life phase. The input and output flows associated with each elementary process are standardized to the functional unit. The life cycle impact assessment (LCIA) is performed using the SimaPro software and the Ecoinvent 3 database by the implementation of the CML-IA baseline LCIA method and the ILCD 2011 midpoint LCIA method. Despite that the addition of recycling phase produces non-negligible environmental impacts, the impact assessment shows that, overall, the scenario with recycling is less impactful on the environment than the scenario without recycling. The recycling of CFRP waste reduces between 25 and 30% of the impacts and requires about 25% less energy. The two LCIA methods used, CML-IA baseline and ILCD 2011 midpoint, lead to similar results, allowing the verification of the robustness and reliability of the LCIA results. The recycling of composite materials with recovery of carbon fibers brings evident advantages from an environmental point of view. Although this study presents some limitations, the LCA conducted allows the evaluation of potential environmental impacts of steam thermolysis recycling process in comparison with a scenario where the composites are directly sent to final disposal. The proposed approach can be scaled up to be used in other life cycle assessments, such as in industrial scales, and furthermore to compare the steam thermolysis to other recycling processes.

Anticipating in-use stocks of carbon fiber reinforced polymers and related waste flows generated by the commercial aeronautical sector until 2050

Carbon Fiber Reinforced Polymers (CFRP) are increasingly used in commercial aircraft. Thus, the amount of in-use stocks of CFRP and related waste flows generated by the aeronautical sector will grow quickly through waste generation of end-of-life aircraft. This publication will provide a prospective assessment of the amounts and their localization of the worldwide in-use stocks of CFRP and related water flows until 2050. It has been found that by 2050 nearly half a million tons of CFRP waste will be generated in total, most of the waste will be located in North America and in Europe with about 162,000t and 145,000t respectively. In fact, this will allow to anticipate the efforts needed to properly recycle those future CFRP waste flows. Thus, this study provides a useful guide on the establishment of a CFRP waste management program, including timeframes and specific recommendations for high priority locations, and finishes with a discussion on the most promising recycling techniques of CFRP waste.

A Novel Sonochemical Approach for Enhanced Recovery of Carbon Fiber from CFRP Waste Using Mild Acid–Peroxide Mixture

A novel sonochemical method is proposed for the recovery of carbon fiber from carbon fiber reinforced polymer (CFRP) composites by treatment with a mixture of dilute nitric acid and hydrogen peroxide in the presence of ultrasound. A maximum resin decomposition ratio of 95% could be obtained for the epoxy matrix. SEM and TGA data showed that the recovered fibers had very little or no epoxy resin and their tensile strength was comparable to that of the virgin fiber. ATR-FTIR, MALDI-TOF/MS, and 1H NMR analysis of the recovered solid and liquid byproducts showed the formation of decomposition products of cross-linked epoxy resin through nitration and oxidation reactions. This process opens the possibilities of an environmentally more benign process for CFRP waste decomposition and recovery of carbon fiber in the presence of ultrasound and H2O2 by eliminating the need for strong chemicals and high reaction temperatures and pressures.