Hybrid tandem catalytic conversion process towards higher-oxygenate e-fuels

Brief description

By 2050, the EU wants to become climate neutral in order to stop global warming and its consequences for the climate. Germany aims to achieve this goal as early as 2045. While electrification is the approach for passenger cars to avoid greenhouse gas and pollutant emissions, defossilization of other transport sectors such as heavy-duty and long-distance land transport, shipping and aviation depends on the availability of fuels with higher energy density and carbon neutrality. Synthetic paraffinic liquid hydrocarbons and light (C1) oxygenates (methanol, DME) renewable fuels are the current options.

Higher (C5+) oxygenates (aliphatic alcohols and ethers) may be a preferred alternative because they can reduce exhaust emissions of volatile organics and soot compared to paraffinic fuels due to their light oxygenate chemical formula. Compared to lighter oxygenates, they offer logistical advantages and better compatibility with current fleet infrastructure.

Goals of the project

E-TANDEM aims to enable efficient and direct production of a new, higher-oxygen, diesel-like e-fuel for marine and heavy-duty applications. This oxygenated fuel is produced directly from CO2 as the sole carbon source and renewable electricity as the sole energy source in a hybrid catalytic process that integrates three major catalytisis branches: High pressure electrocatalytic syngas production coupled to a tandem catalytic e-syngas conversion encompassing solid thermocatalysis for hydrocarbon synthesis (olefin-selective Fischer-Tropsch reaction) with molecular chemocatalysis for in situ oxo-functionalization (olefin reductive hydroformylation reaction). E-TANDEM advances on breakthrough.

Work tasks OWI

Characterization of the newly proposed higher oxygenate e-fuel (HOEF) in its two expressions, i.e., a blend of higher aliphatic alcohols or higher aliphatic ethers, and evaluation of its applicability for marine fleet and heavy internal combustion road engines. This includes:

  • Development of blending strategies with base fuels, i.e. renewable paraffinic fuels (biomass-to-liquids (BtL), hydrogenated vegetable oil (HVO)) and conventional diesel, and additivation to achieve drop-in and backward compatibility with reference to current ISO8217 and EN590 regulations for marine and road diesel fuels for heavy-duty vehicles.
  • Quantify the effects of the higher oxygen content pure e-fuel and selected blends thereof on ignition performance and efficiency, focusing on the profile of soot emissions, using the Yield Sooting Indices (YSIs) formalism.

Performing research centers

  • Agencia Estatal Consejo Superior de Investigaciones Científicas (Koordination)
  • Max-Planck Gesellschaft zur Forderung der Wissenschaften e.V.
  • Danmarks Tekniske Universitet
  • OWI Science for Fuels gGmbH
  • Uniresearch B.V.
  • GoodFuels B.V.
  • University of Zagreb, Faculty of Mechanical Engineering and Naval Architecture
  • King Abdullah University of Science and Technology
  • University of Cape Town

Project Funding

Project duration

10/ 2022 until 10/ 2026


M.Sc. Karin Engeländer
phone: +49 2407 9518148
email: K.Engelaender@owi-aachen.de