Catalytic Effect of Biomass Pyrolyzed Char on the Atmospheric Pressure Hydrogasification of Giant Leucaena (Leucaena leucocephala) Wood

This work explored the activity of biomass pyrolyzed char on the pyrolysis and hydrogasification of Giant Leucaena (Leucaena leucocephala) wood. The effect of char preparation condition, as a slow or fast heating pyrolysis at three different temperatures (650, 750, or 850 degrees C), on carbon conversion and gas product distribution was investigated. The presence of external hydrogen (H-2) had a minor effect on carbon conversion but a significant influence on the gas product distribution. The addition of H-2 without pyrolyzed char favored carbon monoxide hydrogenation, followed by water-gas shift reaction and resulted in higher levels of methane (CH4) and carbon dioxide (CO2). In the presence of pyrolyzed char, the addition of H-2 had a different effect on gas composition with an increased CH4 via the carbon-hydrogen reaction. Moreover, the slow heating pyrolysis at moderate temperature (similar to 750 degrees C) during char preparation provided the most reactive char resulting in tar reduction and increase in CH4 production.