Market Overview

Carbon fiber reinforced plastic (referred to as CFRP hereafter), a composite material of carbon fiber and plastic (resin), is used in various applications, such as aircrafts, wind power generators, pressure vessels, automobiles, and sport & leisure goods. The global CFRP market size is valued at 148,900tonnes in 2022 (estimated by Yano Research Institute), and around 15 to 16 percent of this volume represents scraps generated during the manufacturing process of CFRP. Adding the estimated volume of used CFRP products that are disposed due to end-of-life, the total volume of CFRP waste is estimated to amount to 55,610tonnes in 2022. The volume of CFRP waste is projected to grow in tandem with the growth of the CFRP market.

Meanwhile, out of the 55,610tonnes of CFRP scraps and wastes disposed in 2022, only a fraction, 7 percent, goes to recycle. In detail, the volume of carbon fiber reclaimed (rCF) from CFRP by removing matrix resin from CFRP pre-preg, scrap, and used products is estimated at 2,050tonnes. Compared to the (estimated) production volume of PAN-based carbon fiber (virgin CF [vCF]), it is equivalent to 2 to 3 percent of production volume of PAN-based carbon fiber. As the volume of rCF is expected to increase along with the expansion of the CFRP market, the volume of rCF reclaimed is forecasted to reach 4,400tonnes by 2030.

Major reasons for such as small amount of rCF produced despite the advancements in technology to recycle CFRP are challenges in the quality of rCF, stable sourcing of recyclates, and finding appropriate applications. The quality of rCF is critical in particular, as it directly affects the usage of rCF. Increasing confidence in the quality of rCF is awaited.

Noteworthy Topics

Trends in Technological Development of CFRP Recycling: In Addition to Pyrolysis, Chemical Decomposition is Becoming Practical

There are currently two methods for reclaiming CF from CFRP: Pyrolysis, which has been the most proven technology, and chemical decomposition, which is about to be implemented commercially.

In the process of pyrolysis, CFRP is heated in absence of oxygen to remove resin without oxidatively degrading CF. Since CF is graphitized at a high temperature of 2,000 to 3,000 ℃ in its manufacturing process, the strength does not decrease significantly even when exposed to a temperature of about 500-800℃, the temperature at which the matrix resin decomposes. Recycling companies in Japan mainly adopt pyrolysis using external heating, heated air circulation, or super-heated steam.

On the other hand, recycling of CFRP by chemical decomposition is a method using reaction media such as alcohol and supercritical fluids, taking advantage of the reaction at low temperatures (around 350℃). It includes solvolysis, subcritical and supercritical fluid processes, or fluid treatment. Chemical decomposition is advantageous in reclaiming CF without property degradation, but processing the solvents is very costly.

Although the chemical decomposition methods in Japan remained in process development until mid-2010s, it has been progressing rapidly over the past few years, including some customer trials. As addressing carbon neutrality became a socioeconomical requirement, chemical decomposition is attracting attention as a technology that emits CO2 less than pyrolysis, requiring use of less energy than pyrolysis, and not creating residues of carbonized matrix resin.

Future Outlook

Quality of rCF is difficult to evaluate by appearance. Properties of carbon fiber may be damaged from heat or chemicals when CFRP is treated via pyrolysis or chemical decomposition, while residues of carbonized matrix resin may remain on the surface. For this reason, user companies of industries like automotive, aircraft, and pressure vessels, where safety directly affects people’s lives, are hesitant to large-scale adoption of rCF from quality assurance perspective. To ease the concern, in Japan, industry, government, and academia are embarking on establishing the evaluation test methods collaboratively.

Along with the quality, the challenge associated with the utilization of rCF is the concern over stable sourcing of materials. Supply chain for securing CFRP production scrap and end-of-life materials need to be established. Firm and dependable collection of recyclates will stabilize the supply of rCF.

Regarding the development of appropriate applications for rCF, given the fact that fiber length of rCF is shorter than that of vCF, it cannot simply displace vCF. Viewing by the carbon fiber length alone, one might say turning vCF with long fiber length into rCF is downcycling. Nonetheless, rCF exceeds virgin fiber from sustainability perspective, for it contributes to decarbonization. If rCF can be processed into nonwoven fabrics and compound pellets, it increases value as a material that can be used in a whole new application where vCF could not fit.

Research Outline