Catalytic oxidative steam reforming of bio-ethanol for hydrogen production over Rh promoted Ni/CeO2–ZrO2 catalyst

Abstract

Catalytic steam reforming of bio-ethanol in presence of oxygen for hydrogen production was studied over Ni/CeO2–ZrO2 and Rh–Ni/CeO2–ZrO2 catalysts. The catalysts were prepared by an impregnation-co-precipitation method and characterized by various characterization techniques. Characterization results revealed that addition of ZrO2 improves the oxygen storage capacity of CeO2 which improves catalytic activity. The effects of temperature, ethanol/water/oxygen molar ratio, and space time on ethanol conversion and product selectivities were investigated using a tubular fixed bed reactor at atmospheric pressure. Complete ethanol conversion was achieved at 600 °C with a maximum hydrogen yield of 4.6 mol/mol on the 1%Rh–30%Ni/CeO2–ZrO2 catalyst. Ethanol conversion and H2 selectivity were increased with increasing contact time, while CO and CH4 selectivity decreased. Investigation revealed Rh promoted catalyst exhibited better catalytic activity than 30%Ni/CeO2–ZrO2 catalyst for oxidative steam reforming of ethanol, indicating that addition of Rh improved the catalytic activity significantly by promoting water gas shift reaction.