Synthetic Fuels

In the future, synthetic fuels will primarily be needed to achieve CO₂-neutrality also in hard-to-abate transport sectors, mainly aviation, marine shipping and heavy-duty road transport. In the Bavarian “Center for Sustainable Fuels” (ZENK) in Straubing and Sulzbach-Rosenberg, we are developing new process routes for the synthesis of CO₂-neutral fuels based on renewable resources and energy. The development is conducted at pilot-scale and paves the way for application in a refinery of the future, where all feedstocks and input streams originate from renewable sources.

Our synthetic approach consists of the chemical conversion of alcohols via light olefins (alkenes) as intermediates to middle distillate fuels such as kerosene and diesel (SynergyFuels). The starting materials methanol and ethanol are obtained from CO₂ hydrogenation and fermentation processes. Further catalytic processes (EcoFuel) can then be applied to yield readily refined fuel fractions.

The production of synthetic fuels from CO₂ is particularly space- and resource-efficient. The individual process technologies are already quite well developed, but not yet in an integrated process chain and with synthetic transportation fuels as target product.

Important research questions that we are pursuing at Fraunhofer IGB concern the use of CO₂ from technically relevant sources, in particular from industrial exhaust gases as so-called point sources. Impurities from the upstream industrial processes can significantly impair the performance and lifetime of the catalysts for CO₂ conversion.

Therefore, our work is particularly concerned with process integration and the use of CO₂ from technical sources. This also opens up opportunities to combine biomass-based processes, which often produce CO₂-rich gas streams (e.g. fermentation processes), with the use of CO₂ for fuel synthesis. This way, different material flows can be optimally used in the sense of a biorefinery. 

At a glance

• Climate-neutral production of fuels based on renewable raw materials and energy
• Circular economy
• Independence of fossil fuels
• Decentralized production is possible

• Assessment of the resource base of processes
• Development of suitable processes and process cascades including catalyst screening and optimization
• Process scale-up
• Production of fuel samples
  

In our research and development on synthetic fuels, we would like to collaborate with partners from science and industry who are active in the areas of raw material supply (CO₂, renewable energy), fuel production (catalysts, plant engineering, refineries) and fuel use (logistics, engines, aircraft construction, airlines, shipping companies, etc.). Important questions concern process integration, the relationship between process control/parameters and fuel quality, fuel quality/specifications, CO₂ purity, new catalysts and other exciting issues related to synthetic fuels.