Deoxygenation of dilute and concentrated stearic acid over 2% Pd/C beads was performed in a continuous reactor at 300 °C and 20 bar pressure of Ar or 5% H2/Ar. Stable operation was obtained in 5% H2 atmosphere, with 95% conversion of 10 mol % dilute stearic acid in dodecane and 12% conversion of pure stearic acid. Deactivation took place in H2-deficient gas atmosphere, probably as a result of the formation of unsaturated products and coking in the pore system. Transient experiments with step changes were performed: 1 h was required for the step change to be visible in liquid sampling, whereas steady states were achieved after a total of 2.5–3 h. Postreaction analysis of the spent catalyst revealed that a deactivation profile was formed downward over the catalyst bed.

The present study was focused on kinetic investigation of xylitol aqueous phase reforming with 2.5%Pt/C catalyst in a fixed bed reactor. For kinetic modeling, a complex reaction network was taken into account considering the formation of not only hydrogen and CO 2 but also a range of alkanes in various side reactions. Parameter investigation revealed an adequate description of the experimental data. The influence of mass transfer was elucidated by exploring the parameter space of diffusion and mass transfer coefficients as well as Peclet numbers. Aspen HYSYS software was used to design a hydrogen production plant with 500 kg/h capacity operating with xylitol as a feedstock. Heat consumption of the designed process can be fully covered by heat generated by combusting alkanes formed during APR reaction.

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