In the future, fuel cells with hydrogen as fuel will be used for environmentally friendly and efficient electricity generation. The Reformer Steam Iron Cycle (RESC) developed at TU Graz enables the production of high-purity hydrogen in small plants directly at the consumer by using a chemical looping process. In this process, the oxygen carrier iron oxide is reduced to iron in the reduction step by releasing oxygen into the biogas supplied, thus oxidising the biogas to carbon dioxide and water vapour. In the oxidation step, the iron is oxidised again by the oxygen contained in the supplied water vapour and highly pure hydrogen is produced as a product gas for use in fuel cells.
The research work in the project focuses on increasing the lifetime and stability of the iron oxide and other oxygen carrier materials developed for the process. The oxygen carrier materials are repeatedly reduced and oxidised at temperatures of 600-1000°C. Due to the phase transformations and sintering, the performance of the material for hydrogen production continuously decreases. In the project, both new materials and the influence of innovative manufacturing methods on the service life of the oxygen carrier materials are being investigated. These include, for example, electron- and ion-conducting high-temperature ceramics, which are used as a stable support structure for the oxygen carrier. The newly developed oxygen carriers are tested and evaluated in the laboratory under conditions close to the application and can then finally be used in plants for hydrogen production from biogas.