Tokyo-headquartered Asahi Kasei and Osaka, Japan-based Microwave Chemical have launched a joint demonstration project with the objective of eventually commercialising a new chemical recycling process for polyamide 6.6 using microwave technology.

The process depolymerizes the PA66 to directly obtain the monomers hexamethylenediamine (HMD) and adipic acid (ADA), at high yields and with low energy consumption.

The monomers can then be used to manufacture new PA66. In the demonstration, scraps from manufacturing and post-use waste material of PA66 for airbags and automotive parts are being depolymerized.

Asahi Kasei currently produces fossil fuel-derived HMD and ADA as intermediates to manufacture Leona PA66, an engineering plastic featuring outstanding heat resistance and rigidity. PA66 is used in various applications, including plastic parts for automotive and electronic products and yarns for airbag fabrics, and its demand is expected to increase worldwide.

For chemical recycling, Microwave Chemical is advancing its proprietary PlaWave technology platform for decomposing plastic using microwaves.

Laboratory-scale studies that began in 2021 have confirmed the high-yield depolymerization of PA66 using microwaves, as well as the principle of the separation and purification process after depolymerization. Bench-scale equipment will now be assembled at Microwave Chemical’s Osaka factory by the end of 2023, and a small-scale demonstration trial using this equipment will be performed in 2024, to collect basic process data for commercialisation.

www.asahi-kasei.com