The influence of propene impurities on the PEM fuel cell catalyst
Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
Hydrogen is considered as one of the most important fuels for the near future. Hydrogen is currently being used as a feed gas in fuel cells. It can be produced by a reformate process from fossil sources. The steam reforming is the main technology used. Hydrogen from reforming may contain traces of hydrocarbons besides other products such as , and contaminants. The presence of these impurities may have a negative effect on the catalyst of the fuel cell. As a result of this, the lifetime and the performance of the fuel cell decrease. In this study, the influence of propene on the PEM Fuel Cell performance isinvestigated. The study is focused on the adsorption and deactivation phenomena of low concentrations of contaminant on a Pt/C catalyst. In the experiments, cyclic voltammetry and in-line mass spectrometry to analyze the outlet gas are employed. Different adsorption potentials (0.12, 0.15, 0.20, 0.25, 0.30, 0.35 and 0.40 V), temperatures ( and ) and relative humidities ( and ) are tested. Thereby, the influence of adsorption potential, temperature and humidity on the fuel cell is discussed. The results show that the adsorption of propene is highly potential dependent and is also influenced by the temperature and the relative humidity by shifting oxidation peaks and decreasing the charge density of oxidation, respectively. Propene cannot displace hydrogen already adsorbed. Moreover, at and 90%RH, is the main oxidation product. In addition, some partially oxidized products may be formed. During the reduction of propene, propane was the main product released. It is also possible that some methane is released as well. Using a small quantity of hydrogen with argon as the carrier gas for impurities resulted in a decrease of the adsorbed species formed on the catalyst.
Place, publisher, year, edition, pages
Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-158510OAI: oai:DiVA.org:kth-158510DiVA: diva2:777901