RIKEN TECHNOS Conducts Joint Studies with Shimane University on Potential of Rare-Earth Metal Recovery Technology Using PVC

RIKEN TECHNOS CORPORATION (Head Office: Chiyoda-ku, Tokyo; Representative Director, President & CEO: Kazuaki Tokiwa) is conducting joint research with Shimane University on a technology that recovers rare-earth metals from neodymium (Nd) magnets through a wet mechanochemical process that uses polyvinyl chloride (PVC).

RIKEN TECHNOS started from the manufacturing and selling of PVC compounds, and currently engages in businesses in a wide range of fields, including non-PVC materials and various types of film products. To realize a resource-circulation society, we are also conducting research and development of recycling technologies for after our products are used.

Effective use of PVC is difficult due to the generation of corrosive gases and hydrocarbon residues during degradation.
Amid continued studies and research from multiple angles regarding methods for reusing used PVC products, our attention was drawn to a technology—developed by Professor Ryo Sasai from the Faculty of Materials for Energy, Shimane University—that selectively recovers specific resources from solid waste through a wet mechanochemical process. We are conducting joint research on a resource recovery technology that uses PVC.

The technology developed by Professor Sasai combines an inorganic acid with a wet mechanochemical process. It can selectively recover, as oxalates, rare-earth metals—Nd and dysprosium (Dy)—at high levels of purity from Nd magnets used in electric vehicles, smartphones, and such. At the same time, this technology requires the use of strong acid to encourage dissolution reactions in Nd magnets, and the disposal of waste acid after use is an issue.
Therefore, this joint research focused on the property where hydrogen chloride is generated when PVC is degraded by adding heat and mechanical energy. By combining this PVC degradation reaction with a wet mechanochemical process, hydrochloric acid derived from PVC can be used in reactions, allowing rare-earth metals to be separated and recovered from Nd magnets without having to add new strong acids. It was confirmed that this method is effective in recovering rare-earth metals from Nd magnets while suppressing the amount of waste acid generated.

The results of this joint research are scheduled to be presented at the Ceramic Society of Japan’s Annual Meeting 2026 being held at Yokohama National University from March 4 to 6, 2026.

RIKEN TECHNOS will contribute to the realization of a sustainable society by discovering new possibilities for the effective use of PVC and other plastics containing chloride.

Sasai & Fujimura Laboratory, Shimane University
https://www.ipc.shimane-u.ac.jp/eco_lim_labo/index.html (in Japanese)