The Politecnico di Milano, coordinator of the WORLD – Waste Oils RecycLe and Development project, proposes an innovative, circular and sustainable process to turn used vegetable oil into a valuable resource. The study was published by the British Royal Society of Chemistry in the journal «RSC Sustainability» and was rewarded for its originality by being featured on the cover.

The goal of the WORLD project is to optimise waste vegetable oil treatment processes while improving the quality of end products, reducing waste and fostering European independence in the supply of critical raw materials.

In fact, vegetable oil is used widely around the world, and cooking and food preservation generate an enormous amount of waste oil. Around 4 million tonnes of used vegetable oil are produced in Europe each year, representing just 4% of the total global amount of this abundant, widespread product. If not properly disposed of, this waste can lead to significant environmental impacts.

The WORLD project proposes to recycle used vegetable oil, yielding innovative materials used as bio-lubricants, air purification devices and fine chemical components from petroleum-free precursors. These applications are presented as a supply chain parallel to their use in the production of biodiesel, although this is limited by law to 10% and concerns only the purest fraction of the waste. 

In addition to economic and technological benefits, the project has a strong social and environmental impact: raising awareness of correct waste oil collection can reduce public costs related to incorrect disposal and prevent environmental damage. In addition, a life cycle analysis (LCA) will be conducted to assess the best strategies to minimise ecological, economic and social impacts by adopting a ‘zero waste’ approach. 

«We started by observing that the waste vegetable oil recycling industry is currently based on simple decantation and filtration processes, without adequate scientific optimisation. We therefore analysed two alternative techniques: bentonite treatment and water washing to improve their efficiency and reduce their environmental impact», explained Andrea Mele, Department of Chemistry, Materials and Chemical Engineering “G. Natta”.