Low-temperature mild partial oxidation of ethanol over supported platinum catalysts

Supported platinum catalysts containing 1.2% Pt loaded on Al2O3 (1.2% Pt/Al2O3) and 1.9% Pt loaded on ZrO2 (1.9% Pt/ZrO2) were prepared by incipient wetness impregnation and sol-gel method, respectively. The activity of these catalysts in the partial oxidation of ethanol (POE) was examined in a fixed-bed reactor in a temperature range between 373 and 473 K. The results indicated that significant ethanol conversion (CEtOH > 50%) was found at the low reaction temperature with a feed ratio of O2/EtOH ratio >0.75. Oxygen molecules introduced in reactant were completely consumed in POE reactions performed. H2, H2O, CO and CO2 were the major products detected. The selectivity of hydrogen (SH2) and CO (SCO) varied significantly with reaction conditions. High selectivity of hydrogen (SH2 > 95%) and low selectivity of CO (SCO ∼ 0%) were found from a mild oxidation at TR = 373 K over Pt/ZrO2. However, these two selectivities were drastically deteriorated through oxidation at high TR, high O2/EtOH ratio or over Pt/Al2O3 catalyst.