Pt-Sn/gamma-Al2O3 and Pt-Sn-Na/gamma-Al2O3 catalysts for hydrogen production by dehydrogenation of Jet A-1 fuel: Characterisation and preliminary activity tests

The partial dehydrogenation of fuels like diesel or kerosene cuts to produce H-2 is an emerging idea of increasing interest. In the present work the study of the partial dehydrogenation of Jet A-1 fuel on Pt Sn/gamma-Al2O3 based catalysts to produce H-2 to feed an on-board (aircraft) proton exchange membrane fuel cell is presented. Extensive physico-chemical characterization of 5% wt.Pt-1% wt.Sn/gamma-Al2O3 and 5%wt.Pt-1%wt.Sn-1%wt.Na/gamma-Al2O3 pelleted materials has been performed. A gradient of the active metals from the edge to the centre of the pellet has been observed. A higher concentration of Pt has been detected on the outer part of the pellet than in the inner part, whereas Sn has been detected only on the external part of the pellet. The investigated materials are active as catalysts for the partial dehydrogenation of normal and desulfurised Jet A-1 kerosene fuel. The presence of sulfur compounds and coke deposition strongly affects the H-2 productivity which decreases rapidly with time on stream. The presence of a Na cation addition contributes to give the highest and most sustained H-2 production. The condensed outlet liquid stream retains the fuel properties in the range of the Jet A-1 kerosene fuel. These are encouraging preliminary results, inviting further research; coking and sulfur poisoning as well as identification of appropriate reaction conditions are the main challenges to be overcome in the immediate future.