Honda, Toray Explore Polyamide Chemical Recycling

Toray Industries has signed an agreement with Honda Motor to jointly develop chemical recycling technology for glass-fiber-reinforced polyamide (PA) 6 parts recovered from end-of-life vehicles. The partners have begun verifying a technology that entails depolymerization using subcritical water to obtain raw caprolactam.

Toray and Honda are focusing on the high permeability, dissolving power, and hydrolysis effect in resins of subcritical water in developing a technology that successfully depolymerizes PA 6. Subcritical water is water maintained at an elevated temperature and pressure. It is free of catalysts; additives do not affect it; and it can depolymerize PA 6 in several minutes to create high yields of raw monomer. Separating, refining, and repolymerizing the monomer enables regeneration of PA 6 that performs like a virgin material.

Japan's road map to a circular economy

Japan’s Ministry of the Environment adopted this technology for a fiscal 2023 project to establish a decarbonized circular economy system, including the validation of recycling systems for plastics and other resources. Toray and Honda plan to participate in this project, set up a pilot facility with a processing capacity of 500 tonnes annually of raw resin, and conduct validation testing.

The first step is to recycle used automotive plastic parts into the same automotive materials. The two companies will develop depolymerization and monomer separation and refining technologies by employing intake manifolds as raw materials for engine intake system parts. They seek to apply these technologies for recycling chemicals in automotive resin parts by around 2027.

Broadening scope of chemical recycling

Down the track, they look to broaden the scope of their chemical recycling technology to encompass apparel, films, and other non-automotive applications. They also envisage inviting other companies to take part in their effort and set up a chemical recycling scheme for nylon 6 in Japan. This endeavor would help the realization of a circular economy and cut greenhouse gas emissions.

One goal of the Toray Group Sustainability Vision for 2050 is to contribute to a world in which resources are sustainably managed. Toray will keep pursuing research and development to contribute to a sustainable, circular economy and thereby realize its corporate philosophy of contributing to social progress by delivering new value while attaining sustainable growth.