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New project will convert surplus power into environmentally friendly chemicals

Energy Physics Chemistry Electrochemistry Catalysis

A wide variety of chemicals and materials which we use today require energy intensive and environmentally harmful synthesis methods. The new research project, Proactive, targets this problem. It aims to develop new catalytic methods to which electricit is used to drive chemical synthesis. Researchers from DTU Physics participates in the project.

- We will be conducting fundamental studies to elucidate how to synthesise chemicals using electrochemical methods at low temperatures and pressures. We are particularly interested in synthesizing metastable compounds, which can be difficult to form at high temperatures, explains Ifan Stephens, associate professor at DTU Physics.

In particular, the researchers from DTU Physics have two target reactions: The electrochemical reduction of O2 to H2O2 (hydrogen peroxide) and the partial oxidation of hydrocarbons:

1) Hydrogen peroxide is a highly valuable chemical, mainly used as an environmentally friendly oxidising agent for bleaching paper and textiles or disinfecting water. The challenge is to find a catalyst that can reduce O2 to H2O2, without forming the more thermodynamically favoured product, water. The researchers recently showed that this was possible using an alloy catalyst consisting of platinum and mercury (Nature Materials 12, 1137). In Proactive the goal is to replace the platinum-mercury catalyst with a material that is free of precious or toxic metals. This would enable hydrogen peroxide to be produced on a localised scale, on demand, and close to the point of consumption.  

2) Acrolein or acrylic acid are valuable chemical building blocks usually produced by oxidising propene at high temperatures; under these conditions it is challenging to avoid forming the most thermodynamically favoured product, CO2.  By performing the reaction electrochemically, at low temperatures and pressures, the researchers anticipate that it will be possible to produce these chemicals without forming CO2. Moreover, the process could be less energy intensive and hence more environmentally friendly.

- As for H2O2 production, judicious design of the catalyst material is key to a successful outcome in this progress, concludes Ifan Stephens.

Societal impact
- The short-term perspective is that we don't need explosive materials for the production. One can get better terms and decentralized production instead of large chemical plants, explains Jan Rossmeisl, project manager and professor at the Department of Chemistry, University of Copenhagen. He continues:

- In the long term there is no alternative, as I see it. Today chemical products are manufactured using oil, because oil already has energetic bonds that you can perform chemistry with. But if we need to base our chemical production on a foundation of water and CO2 in the future, we need a way to put energy into chemical bonds. This can be done with electrochemistry.