Catalytic partial oxidation of higher hydrocarbon fuel components on Rh/Al2O3 coated honeycomb monoliths

Catalytic partial oxidation (CPOX) can efficiently be used for the autothermal conversion of logistic fuels to hydrogen and synthesis gas in compact reactors to supply fuel for portable and stationary fuel cells. CPOX of characteristic constituents of logistic transportation fuels are studied experimentally in Rh/ Al2O3 coated honeycomb monoliths at short contact times. Towards a fundamental understanding, the effect of the chemical structure of various hydrocarbon fuels on conversion and yield as well as the formation of coke precursors is investigated. Benzene, cyclohexane, 1-hexene and i-hexane are used to represent archetypically different classes of hydrocarbons in transportation fuels. The influence of the chain length of fuel components was evaluated by comparison of a series of linear alkanes ranging from n-hexane to n-dodecane. The effect of side chains of cyclic hydrocarbons has been studied by methyl substitution of benzene and cyclohexane. The role of the basic structure of the employed hydrocarbons is shown to dominate both production of synthesis gas and the formation of cracking products such as olefins and other coke precursors. Based on the knowledge of the behavior of the different chemical constituents of logistic hydrocarbons reference fuels can be derived. 2009 Elsevier B.V. All rights reserved.