Australia mallee wood, bark and leaf samples (Eucalyptus loxophleba, subspecies lissophloia) were pyrolyzed to produce volatiles for in situ catalytic steam reforming with ilmenite as a catalyst. The results demonstrated that the properties of biomass feedstock (wood, bark and leaves) significantly influenced their product yields and properties. Bark produced the highest amounts of solid products, whereas leaf generated the highest amounts of tar during pyrolysis. The differences in the chemical composition and the tar yields among wood, bark and leaf decreased with increasing temperature. It is also found that ilmenite showed good activity for the reforming of all tars from different parts of mallee trees. However, its activity for reforming tar from bark and leaf decreased with prolonging feeding time due to their high gradual coke deposits. Compared with sintering, the accumulated coke deposited on ilmenite is a dominant factor to its deactivation during the steam reforming process. Burning coke is an effective method to regenerate the catalyst activity of ilmenite. (C) 2012 Elsevier Ltd. All rights reserved.