HYDROGEN PRODUCTION FROM SELECTED KEROSINE COMPONENTS BY PARTIAL CATALYTIC DEHYDROGENATION

Kurzfassung

The providing and storage of hydrogen for efficient fuel cell systems is an on-going challenge. The partial catalytic dehydrogenation (PCD) of liquid fuels can provide stationary or mobile fuel cell systems with hydrogen. Through PCD, liquid fuels can be treated as hydrogen storage as well as an energy provider for combustion processes. It is also an alternative to the common reforming processes where the fuel is converted with steam into a hydrogen rich product gas with co- products like carbon monoxide and carbon dioxide that requires CO clean-up before feeding into a proton exchange membrane fuel cell. The direct dehydrogenation on a catalyst can provide a hydrogen product gas of high purity (95 vol-%) without carbon monoxide or carbon dioxide. The hydrogen is partly removed and the fuel is not completely transformed into a gaseous product. Therefore the partial dehydrogenated fuel can be used for further processes. At the Institute of Technical Thermodynamics of the German Aerospace Centre, a test rig was built for the PCD of kerosene, to investigate the product gas quality, the by-products, and hydrogen yield. A big challenge for PCD catalyst is the sulphur content, on average 500 ppmw, of kerosene [1]. To remove sulphur components from kerosene, thermal fractionation by rectification is suitable based on the boiling range of kerosene. The process concept for the PCD with fuel cell system includes the desulphurization of kerosene or the use of desulphurized kerosene (DK) (3ppmw sulphur).