Eni launches authorisation process in Priolo for new biorefinery and chemical recycling plant for plastics

Eni has initiated the authorisation process for the Environmental Impact Assessment (VIA) to redevelop its industrial site in Priolo, Sicily. Recently, Italy’s Ministry of the Environment and Energy Security approved Eni’s proposal to move forward with the construction of a new biorefinery and a chemical recycling plant featuring Versalis’ proprietary Hoop® technology.

The project will repurpose the area currently occupied by Versalis’ ethylene plant, which will be gradually phased out, along with an adjacent zone used for site services. The new biorefinery will have an annual production capacity of 500,000 tonnes, using mainly waste and residue feedstocks of vegetable and animal origin, as well as vegetable oils. Alongside the Ecofining™ plant, the project will include a pre-treatment unit for biogenic feedstocks and a hydrogen production facility.

Once completed, the Priolo biorefinery will become the second of its kind in Sicily—following the Gela plant, which has been operational since 2019. It will produce HVO diesel for road, marine, and rail transport, as well as SAF-biojet for the aviation sector, with a high degree of operational flexibility. Project completion is expected by the end of 2028.

The Versalis Hoop® plant will utilize the company’s advanced chemical recycling technology, which relies on the pyrolysis of mixed plastic packaging waste. Designed to process up to 40,000 tonnes annually, the plant will yield about 32,000 tonnes of pyrolysis oil. Following the commissioning of a Hoop® demonstration facility in Mantua in June 2025, the Priolo site will mark the first industrial-scale deployment of this technology. The Hoop® process complements mechanical recycling by converting mixed plastic waste into feedstock for new plastic products suitable for diverse uses, including food-grade and pharmaceutical packaging.

Developed in collaboration with Italian engineering firm S.R.S. (Servizi di Ricerche e Sviluppo), the Hoop® technology features high recovery efficiency and remarkable feedstock flexibility. This is achieved through a combination of a high-performance pyrolysis reactor and advanced polymer characterization and process optimization tools powered by Artificial Intelligence.

The Priolo transformation plan—first announced in October 2024 and formalized in March 2025 through an agreement with the Ministry of Enterprises and Made in Italy (MIMIT)—underscores Eni and its subsidiaries’ commitment to their decarbonization and circular economy goals.