The Japan Steel Works, Ltd. (JSW) and Kirin Holdings Company, Limited’s Package Innovation Research Institute conducted a demonstration test using full-scale equipment on “alkaline depolymerization” technology, which chemically breaks down PET—the raw material used in PET bottles and similar products—down to the molecular level. Using a twin-screw kneading extruder (TEX® series) developed by JSW, the companies succeeded in breaking down more than 95% of the PET fed into the machine, and established conditions for stable processing at a rate of over 250 kg per hour. The demonstration also yielded insights into equipment specifications and operating conditions needed to design a mass-production process.
PET is made up of small molecules linked together in chains, and if these can be broken back down into individual molecules, the material can be regenerated as new PET resin. Conventional recycling technologies have mainly relied on breaking down PET at high temperatures over long periods of time, which posed challenges in terms of energy consumption and cost. This new approach combines chemical reactions using reagents with mechanical mixing and friction, allowing the material to be broken down quickly and with less energy, rather than relying on heating alone. According to the two companies, this is the first domestic demonstration of this kind assuming mass production using this type of machine.
JSW was responsible for equipment design and examining operating conditions, while Kirin handled the underlying technology development. Details of the research results are scheduled to be presented at the 57th Autumn Meeting of the Society of Chemical Engineers, Japan, to be held in September 2026. Going forward, the companies plan to develop the entire recycling process, from PET collection through depolymerization to material recovery, while also verifying applicability to a wider range of raw materials, including non-food-grade PET, in order to accelerate efforts toward practical implementation. They also intend to promote collaboration with a diverse range of partners, including companies, local governments and research institutions.
【Press release】【JSW / Kirin】Successful Demonstration of Japan’s First PET Alkaline Depolymerization Technology
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