From chip shop grease to efficient fuel alternative

The process utilizes enzymes to break down fatty acids in cooking oil, transforming them into alkenes, essential components of fuels like petrol and diesel. The researchers envision this renewable fuel, derived from food waste, as a powerful tool in cutting greenhouse gas emissions and reducing fossil fuel dependency.

Biofuels, derived from organic material such as vegetable oil or animal fats, have long been promoted as a sustainable alternative to fossil fuels. Some biofuels, particularly those made from food waste, have been shown to reduce greenhouse gas emissions by up to 94%. However, traditional fatty acid-based biofuels often have lower energy efficiency due to oxygen content, requiring more raw materials and doubling production costs compared to fossil fuels.

Dr. Alex Brogan, Senior Lecturer in Chemistry at King's College London, highlighted the transformative potential of this new method: "As a child, I remember canisters of oil sitting outside chip shops, soon to be cut with diesel and put in the back of a car - for a long time the smell of grease and questionable legality was the only thing people knew about biofuels. However, they are going to be a vital way that industries like logistics divest away from fossil fuels. Without a significant investment in the technology, countries like the UK are going to get further and further from meeting their emissions targets. What we've created is the chemical equivalent of the fossil fuels we're using every day, meeting all the standards the chip shop fat of yesteryear could not."

The innovation hinges on a modified enzyme called P450 decarboxylase. By enhancing this enzyme, researchers were able to efficiently strip oxygen from fatty acids found in food waste, significantly increasing the yield of alkene. Unlike conventional methods requiring water, the team employed liquid salt and UV light, activating the enzyme to achieve a higher alkene yield. This approach minimizes energy consumption and reduces raw material requirements, improving the sustainability of biofuel production.

Additionally, the process eliminates the need for environmentally damaging conventional catalysts, such as platinum, and avoids the use of toxic chemicals like hydrogen peroxide.

Dr. Leticia Zanphorlin, Principal Investigator at the Brazilian Biorenewables National Laboratory, commented on the broader implications: "Our (bio)technology enables us to expand into other renewable materials and produce a variety of fuels, including gasoline and kerosene for the aviation sector. We recognise that much work remains, and are excited to contribute to addressing one of the world's greatest challenges: climate change."

The team aims to adapt the modified enzyme technology for other fields, such as pharmaceutical production, further broadening its potential applications.

Research Report:Enhancing the reactivity of a P450 decarboxylase with ionic liquids!