Cosmo Oil and three Japanese partners are set to put naphtha produced as a by-product of sustainable aviation fuel (SAF) production to work as a lower-carbon feedstock for chemicals and plastics, opening a new pathway for used cooking oil to replace fossil resources beyond aviation.

 

Cosmo Oil Co., Maruzen Petrochemical Co., UBE-Maruzen Polyethylene and Saffaire Sky Energy will begin utilizing used cooking oil-derived naphtha produced at Cosmo Oil’s Sakai Refinery in Osaka.

 

The initiative links SAF production with the chemicals and plastics supply chain, allowing a co-product of aviation fuel production to be used in the manufacture of basic chemicals and polyethylene products.

 

Saffaire Sky Energy will manufacture the naphtha, Cosmo Oil will supply it under a mass-balance system, Maruzen Petrochemical will use it to manufacture basic chemicals, and UBE-Maruzen Polyethylene  will turn those materials into polyethylene and plastic products.

 

The naphtha is produced at the SAF facility operated by Saffaire Sky Energy on the premises of Cosmo Oil’s Sakai Refinery. Completed in December 2024, the facility is Japan’s first large-scale SAF production plant of its kind and began production in fiscal 2025.

 

The used cooking oil-derived naphtha has also obtained certification under the International Sustainability and Carbon Certification (ISCC) system.

 

The companies say the move is aimed at cutting carbon emissions associated with chemical raw materials, where naphtha is a critical feedstock for a broad range of products.

 

Unlike conventional fossil-derived naphtha, bio-based naphtha made from used cooking oil can provide a lower-carbon alternative while allowing existing manufacturing processes to be used.

 

The companies will apply the ISCC PLUS mass-balance approach, which allows the sustainability attributes of biomass-based or recycled feedstocks to be allocated to products in proportion to their use in the production process.

 

The initiative builds on a Japanese government-backed effort launched in 2021 to establish a domestic supply chain for SAF made from used cooking oil.

 

Saffaire Sky Energy said the project creates value beyond aviation by putting the SAF production by-product to use as a chemical feedstock.

 

“Since 2021, with the support of the Japanese government, the Ministry of Economy, Trade and Industry’s Agency for Natural Resources and Energy, and NEDO, Saffaire Sky Energy has been working with JGC Holding, Cosmo Oil, and REVO International to commercialize domestic SAF.

 

"Through this initiative, in addition to producing SAF, we have created new value by utilizing used cooking oil-derived naphtha, a co-product of SAF production, as a chemical feedstock. We find it highly significant that the results of our efforts to promote resource recycling by repurposing domestic used cooking oil as a feedstock can contribute to decarbonization not only in the aviation sector but also in the chemical industry. Going forward, we remain committed to expanding the circular use of sustainable resources and effectively utilizing domestic biomass resources.”

 

The four companies plan to increase supply volumes and develop additional applications for the material, targeting industries including chemicals, textiles and packaging.

 

Cosmo Oil said the ISCC PLUS certification will help support traceability and management of sustainable raw materials.

 

“This initiative, backed by ISCC PLUS certification, helps ensure traceability of sustainable raw materials while enabling their appropriate management under the mass balance approach. Going forward, we will continue to work to expand our use of sustainable raw materials.”

 

Maruzen Petrochemical said it plans to expand sales of sustainable products made using used cooking oil-derived naphtha.

 

“At Maruzen Petrochemical, we aim to expand sales of sustainable products by applying the ISCC PLUS mass balance approach to derivatives and product groups produced utilizing used cooking oil-derived naphtha as a feedstock and marketing them as ISCC PLUS-certified products.”

 

UBE-Maruzen said it will focus on developing products based on lower-impact raw materials.

 

“Ube-Maruzen is committed to developing products utilizing environmentally friendly raw materials and contributing to the realization of a sustainable society.”

 

The companies said the initiative could help extend the use of domestic biomass resources across multiple industries while building a more circular supply chain around used cooking oil.