This study presents the hydrogen production from partial oxidation of methanol (POM) under sprays and dual-catalyst bed. In the experiment, two different catalysts of h-BN-Pt/Al2O3 and h-BN-Pd/Al2O3 with low Pt and Pd contents (0.2 wt%) are utilized. The effects of different preheating temperatures (100, 150, 200, 250, 300 °C), O2-to-methanol molar (O2/C) ratios (0.4-0.8), and Pt/Pd ratios (0:1, 1:2, 1:4, 1:9) on POM are also examined. The results show that a preheating temperature as low as at 100 °C can lead the Pd catalyst to trigger a POM reaction. Nevertheless, there is no significant effect on performance with increasing preheating temperature. Because of the autothermal property from the Pt catalyst during POM, it can be used to replace the preheating system in this study. The Pt catalyst is placed as the upper layer to provide heat for the Pd catalyst layer. The maximum H2 yield (1.61 mol (mol methanol)-1 ) is observed at O2/C=0.6. In this study, reducing the amount of the Pt catalyst does not significantly affect POM performance. The methanol conversions are close to 100% and H2 yield is from 1.55 to 1.57 mol (mol methanol)-1 . Overall, POM can be triggered by preheated h-BN-Pd/Al2O3 or by a dualcatalyst bed (h-BN-Pd/Al2O3 and h-BN-Pt/Al2O3) without preheating to produce hydrogen. It is noteworthy that the POM performed by a duel-bed catalyst together with a small amount (3g) of Pt catalyst can achieve a similar CH3OH conversion and hydrogen production to that which use a full Pd catalyst with preheating.
Keywords Partial oxidation of methanol (POM), Sprays, Dual-catalyst bed, Noble-metal catalyst, Hydrogen production