Prof. Dr. Roland Marschall at the apparatus for gas-phase photocatalysis in his Bayreuth laboratory for physical chemistry. Photo: C. Wißler.
Nitrogen is the main component of fertilisers and is indispensable in numerous other industrial products as well. Almost every nitrogen atom these contain comes from ammonia. The process used worldwide to produce ammonia was discovered at the beginning of the 20th century by chemists Fritz Haber and Carl Bosch. Its great economic importance results from a chemical peculiarity: nitrogen exists mainly in the form of dinitrogen molecules (N₂), which make up almost 80 per cent of the air we breathe. In these molecules, two nitrogen atoms are bound together by an extremely strong triple bond. The Haber-Bosch process is so far the only industrial process capable of breaking this bond. In this process, dinitrogen and hydrogen (H₂) are converted into ammonia. Ammonia molecules each contain only a single nitrogen atom and can thus serve as the raw material for a variety of nitrogen-containing products.
However, the Haber-Bosch process has one major disadvantage: it consumes a lot of energy and is associated with high emissions of the greenhouse gas CO₂. The new Priority Programme (SPP 2370) therefore aims to research environmentally friendly and cost-effective alternatives to turn dinitrogen into industrially usable nitrogen. This can, but does not necessarily have to be done by producing ammonia. However, ammonia is advantageous in that it contains not only one nitrogen atom but also three hydrogen atoms. For this reason, it is considered by researchers to be an attractive medium for storing hydrogen. In contrast to the Haber-Bosch process, which is used globally only in about one hundred industrial plants, the sustainable process now being envisaged would enable decentralised nitrogen conversion powered by solar and wind energy at many locations around the world. This would eliminate the need for the long and energy-intensive transport of ammonia.
SPP 2370 will apply three catalytic methods that may be relevant for the development of a sustainable nitrogen conversion process: electrocatalysis, photocatalysis, and photoelectrochemistry. This is the first research programme in Europe to give equal weight to all three of these methods in the search for a sustainable alternative to the Haber-Bosch process. The participating research groups will combine empirical and theoretical research approaches as well as new findings in reaction engineering.
"We are confident that by consistently integrating different perspectives and methods, we will succeed in developing new alternatives for dinitrogen conversion. We are not seeking to improve the already optimised Haber-Bosch process even further. Instead, our goal is to research decentralisable, climate-friendly, sustainable alternatives," says coordinator Prof. Dr. Roland Marschall, Chair of Physical Chemistry III at the University of Bayreuth.
The research work of SPP 2370 will be spread across various universities and institutes in Germany. Prof. Dr. Roland Marschall has developed the programme together with Prof. Dr. Ulf-Peter Apfel (Ruhr University Bochum), Prof. Dr. Anna Fischer (Albert Ludwig University of Freiburg), Prof. Dr. Martin Oschatz (Friedrich Schiller University Jena), and Prof. Dr. Dirk Ziegenbalg (Ulm University).
Contact for scientific information:
Prof. Dr. Roland Marschall
Physical Chemistry III
University of Bayreuth
Phone: +49 (0)921 55-2760
E-mail: roland.marschall@uni-bayreuth.de
