Power2C4: By catalysis from ethanol to butadiene

"Virtual Institute – Electricity to Gas and Heat" develops Power-to-X process for the production of butadiene

© Fraunhofer UMSICHT

Power-to-X

Butadiene and other C4-olefins are produced with the help of electric current.

© Fraunhofer UMSICHT

Catalyst development

The challenge is to combine the catalytic properties required for the overall reaction in one system.

Project goals

The goal of Power2C4 is to develop a new catalytic process for the production of butadiene and other C4-olefins from a synthesis gas of CO2 and electrolytically produced H2. The focus is on a two-step butadiene synthesis: In the first step, ethanol is produced from the synthesis gas, which is converted to butadiene in a second step using a new catalyst. For this synthesis to succeed, a suitable catalyst system must be identified and tested. Subsequently, the entire power-to-butadiene process chain is evaluated – with a view to both the economic efficiency of the process chain and the sustainability of the new production path for butadiene. The framework for the work package is provided by the "Virtual Institute – Power to Gas and Heat" – a consortium of research institutes working on adaptive technology measures for the power, gas and water system.

Project benefits

Butadiene plays an important role in industry: the unsaturated hydrocarbon is used in the production of synthetic rubber. Until now, butadiene and other C4 olefins have been produced by thermal cracking of the petroleum fraction naphtha. Due to the scarcity of oil reserves and the resulting increase in the price of naphtha, sustainable, alternative production processes based on power-to-x are gaining in importance.

Another advantage of the alternative production process of butadiene is that it helps to compensate for temporary and spatial differences between the production and demand for electricity from renewable energies. In other words, surplus electricity from wind power or photovoltaic plants is used to produce another product - in this case C4-olefins.

Challenges

The conversion of ethanol to butadiene takes place in several coupled reaction steps – from the formation of acetaldehyde via aldol condensation to dehydration. For each of these intermediate steps, a catalyst with special functionality is required to ensure a conversion with high activity and corresponding selectivity. The challenge is to combine the catalytic properties required for the overall reaction in one system. With a multifunctional catalyst, the conversion of ethanol to butadiene without intermediate reaction steps could be realized in a direct process and thus significantly more energy and resource efficient.

Preliminary investigations at Fraunhofer UMSICHT have already identified a promising new catalyst material based on the mineral saponite. This material is now being further developed and optimized for the direct synthesis of butadiene and other C4 hydrocarbons from ethanol.

Project partners

  • Gas and Heat Institute Essen e.V. (GWI)
  • Institute of Energy Economics at the University of Cologne (ewi)
  • Research Center Jülich (FZJ)
  • Ruhr-University Bochum (RUB), Chair of Fluid Process Engineering
  • Wuppertal Institute (WI)
  • ZBT Duisburg (ZBT)