Energy & Fuels, Vol.26, No.7, 4195-4204, 2012
Reaction Kinetics of Glycerol Steam Reforming Using a Ru/Al2O3 Catalyst
Hydrogen (H-2) production by steam reforming represents a candidate method for the utilization of the surplus amounts of biodiesel's crude glycerol. In this work, reaction kinetics of glycerol steam reforming is studied in a fixed-bed reactor, using a Ru/Al2O3 catalyst. The investigated reaction belongs to the kinetically controlled reaction regime systems. It is found that, in the studied ranges of temperature, 350-500 degrees C, and W/F-AO ratio, 0.4-1.98 g h/mol, the reaction order with respect to glycerol is one. At 500 degrees C, the first-order reaction rate constant equals 4.2 X 108 cm(3)/(g(cat) h). From the temperature dependence of the rate constant, the activation energy (21.2 kJ/mol) is evaluated. Finally, it is found that a heterogeneous kinetic model described in a previous work also suggests first-order kinetics at the low glycerol partial pressures used for this study. Using Ru/Al2O3, we have reported reaction kinetics at low temperatures (T <= 500 degrees C). Our work will facilitate the design and operation of reactors producing H-2 from glycerol.