Assessing tar removal in biomass gasification by steam reforming over a commercial automotive catalyst

Methanol was 95% converted to synthesis gas at 700 °C and the catalyst did not deactivate during 48 h on stream. Methanol/water mixtures containing 4925 ppm gasification tar also reacted readily over the catalyst to produce syngas, but catalyst deactivation occurred over tens of hours of continuous operation, indicated by decreased conversion of the methanol/tar feed. The catalyst was regenerated by calcining in air at 500 °C, which allowed catalyst to operate for 120 h. Methanol/water/guaiacol mixtures also reacted readily to produce syngas, but as with tar, the catalyst deactivated over tens of hours continuous operation with methanol/guaiacol feed. SEM data confirmed that coking of the catalyst was the likely cause of deactivation. At relatively high reaction temperature and contact times of seconds used in this study, guaiacol was completely deoxygenated, but a fraction of the guaiacol was methylated over the catalyst to form methyl-substituted benzenes, toluenes and xylenes (BTX).