25 07 2022

Jet fuel production from biobased molecules via catalytic condensation

Current bio-based alternatives for jet fuel (HVO/HEFA) rely on scarce and geographically dispersed feedstocks, such as used cooking oil and animal fats, that cannot cover the fuel demand and sustainability targets of the aviation sector. The HIGFLY project will develop the next generation of technologies to produce advanced renewable jet fuels from abundant and sustainable biomass feedstocks.

The project focuses on the under-utilised and challenging five-carbon (C5) saccharide (hemicellulose) fraction from lignocellulosic biomass and equivalent carbohydrates in other biomasses and biorefinery streams. For this, HIGFLY develops a combination of technologies that produces furfural and bio-oxygenates from C5 biorefinery streams using novel reactor technology, catalysts and solvents, and catalytically upgrades these intermediates to yield hydrocarbons in the kerosene range suitable for blending with jet fuel. The jet fuel synthesis comprises of two stages:

  • Condensation to produce aldol products with the target number of carbons (C8-C15).
  • Hydrodeoxygenation to upgrade the aldol products to saturated hydrocarbons.

A variety of catalytic materials have been screened to determine their activity in the formation of aldol C8-C15 products from furfural and other biobased oxygenates with ketone functionalities. Catalytic materials with the most promising properties and activities for this process have been further formed into pellets/extrudates and will be tested in fixed bed reactors using low temperature liquid phase and high temperature gas phase process regimes to assess catalyst stability and process performance.

Preliminary work achieved in Work Package 3 by TNO, Johnson Matthey and Fraunhofer has demonstrated the viability of the condensation of furfural and biobased oxygenates such as acetone, cyclopentanone and cyclopentanol to attain aldol products under continuous operation.