Illinois researchers convert food waste into jet fuel, boosting circular economy | By converting food waste into sustainable aviation fuel (SAF) that meets industry standards could help the aviation industry meet its ambitious goal of net-zero carbon emissions by 2050.

From the article: Airplane travel is more popular than ever, and our desire for fast transportation means jet fuel has become a major contributor to greenhouse gas emissions. Now, [researchers](https://www.nature.com/articles/s41467-025-64645-y) at the University of Illinois Urbana-Champaign have discovered a novel way to address that problem—by converting food waste into sustainable aviation fuel (SAF) that meets industry standards without relying on fossil fuel blends. Their process, described in a new Nature Communications study, could help the aviation industry meet its ambitious goal of net-zero carbon emissions by 2050.

The process in a nutshell is this: The researchers convert food waste into biocrude oil through a thermochemical conversion process called hydrothermal liquefaction, or HTL. Next, they remove impurities from the biocrude oil, and finally, they refine it with the use of hydrogen and catalysts to turn it into aviation fuel.

This approach can be applied to a variety of feedstocks and types of oil, potentially leading to a new direction for obtaining fuels.

“HTL basically mimics the natural formation of crude oil in the Earth. It uses high heat and pressure to convert wet biomass into a biocrude oil. The goal of this work is to upgrade that biocrude oil into transportation fuels that can go directly into existing energy infrastructure,” said lead author Sabrina Summers, who recently graduated with a doctoral degree from the Department of Agricultural and Biological Engineering (ABE), part of the College of Agricultural, Consumer and Environmental Sciences and The Grainger College of Engineering at U. of I.

In this project, the researchers used waste from a nearby food processing facility. Globally, over 30% of food is wasted annually at all levels of the supply chain — from farm to transportation, processing, retail, food service, and households. Food decomposition in landfills and wastewater treatment plants further contributes to greenhouse gas emissions, and recycling waste helps promote sustainability.

But HTL can process feedstock from a wide range of biowaste, including food, sewage sludge, algal bloom, swine manure, and agricultural residue.

“To meet the aviation industry’s goals to decarbonate jet fuel, we need many different renewable sources, and agriculture is going to play a critical role in terms of providing the feedstocks,” said ABE professor and corresponding author Yuanhui Zhang.

To convert biocrude oil into jet fuel, the researchers first removed impurities such as moisture, ash, and salt. They then used a process called catalytic hydrotreating to eliminate unwanted elements like nitrogen, oxygen, and sulfur—leaving behind only the hydrocarbons needed for fuel. After testing dozens of options, they identified cobalt molybdenum as the most effective commercially available catalyst to drive the necessary chemical reactions and refine the oil into sustainable aviation fuel.