Green hydrogen production is seen as a vital element of Germany’s transition to climate neutrality. However, the gas is notoriously flammable, volatile and complicated to store. It can be transported within ammonia, but a team at the University of Duisburg-Essen (UDE) have set out to find a more stable alternative in the project “Me2H iron-steam process”.
Under the guidance of Professor Rüdiger Deike, the researchers are pursuing an approach to hydrogen (H2) transport based on a well-established iron-steam cycle. In a first step, water is split into hydrogen and oxygen via electrolysis using green electricity provided by solar photovoltaics. In a subsequent process, that H2 is reacted with iron ore containing the oxides haematite (Fe2O3), magnetite (Fe3O4) and wuestite (FeO) to obtain a reduced form of iron oxide (wuestite) mixed with iron (Fe).
The metal compound can then be easily transported as pellets or briquettes without any environmental risk. And when it reaches its destination, it is re-oxidised with steam to produce magnetite and hydrogen. The H2 gas is pure enough to be used in fuel cell electric vehicles and generators.
The researchers are primarily focusing on identifying the most suitable iron alloys for achieving the greatest amount of H2 with minimal loss. “We want to develop the most efficient combination consisting of the best material systems and the process technology tailored to them,” Deike explains in a . Due of the steps involved, the scientists assume the process is best suited to sunnier regions where there is an abundance of water, for example, South America and certain parts of Africa and Australia.
The German Federal Ministry of Education and Research (BMBF) is funding the project over three years with EUR 1.3 million as part of the ‘Hydrogen Republic of Germany’ initiative. Alongside UDE, the Clausthal University of Technology and the Leibniz Institute for Materials Engineering (IWT) in Bremen are also involved as well as the commercial partners ThyssenKrupp Steel Europe and SMS group.