The aim of this work is to investigate the catalytic properties, i.e. activity, selectivity and stability of nickel‐substituted Ba‐hexaaluminates for the cracking and steam‐reforming of a tar in product gas from biomass gasification. A lab‐scale set‐up has been constructed, consisting of a quartz reactor placed in a vertical oven, filled with the catalyst bed material. Methyl‐naphthalene was chosen as a tar model substance since naphthalene is considered to be especially difficult to reform, and since it is in liquid form at room temperature it is easier to handle than the solid naphthalene. A gas stream containing nitrogen gas, steam and methyl‐naphthalene was passed through the reactor and the resulting gas was analyzed by GC‐FID and GC‐TCD. Different catalyst compositions have been tested at different temperatures. The activity, stability and the product distribution was investigated as function of the temperature for the Ni‐substituted catalysts. In this study, three catalysts with different Ni‐substitution levels were used; BaNiAl11O19, BaNi1.5Al10.5O19and BaNi2Al10O19.

The physical demands for an optimal cracking and steam reforming catalyst is a high surface area, thermal stability, abrasion resistance, and a capacity to withstand high gas velocities. Additionally it has to resist the process steam, as steam is well known to enhance sintering of porous materials. Hexaaluminate is a well

‐known high‐temperature material with properties that may well answer to these requests. If it can be substituted to a high catalytic activity this material may well be a good candidate for steam reforming. Our results show that we have synthesized a material with the desired composition and structure. The activity tests show that we have a good reforming ability from all the catalytic materials, but with an increased activity for BaNi2Al10O19. At 1000°C all methyl‐naphthalene was decomposed in all three cases and also at 900°C for the BaNi2Al10O19. There was no char deposition in the catalyst bed and the pore size distribution was unaffected after approximately 50h on stream.

In our continuing studies we will use synthesis gas instead of nitrogen and we will also examine the effect of catalyst poisons like hydrogen sulfide and chlorine.The synthesized BaNi‐hexaaluminates has proven to be very interesting candidates for a new, more resistant steam reforming catalyst in the aim of producing synthesis gas of a high quality.