Production of hydrogen via steam reforming of bio-oil over Ni-based catalysts: Effect of support

Nickel-based catalysts supported on zirconia (Ni/ZrO2) were prepared, characterized and tested for the production of hydrogen via steam reforming of bio-oil. The effects of metal loading on the hydrogen (H2) and carbon monoxide (CO) yields and the carbon deposition percentage were investigated. In order to examine the effect of support, the results obtained on zirconia support were compared to the results obtained over nickel-based catalysts supported on alumina (Ni/Al2O3). It was found that the Ni/ZrO2 catalysts presented higher activity than those supported on alumina for hydrogen production. The CO yields obtained over Ni/ZrO2 catalysts were also higher than those obtained over Ni/Al2O3 catalysts. A potential H2 yield of almost 80% can be obtained at 850 °C using Ni/ZrO2 catalysts with a nickel content of 14%; whereas, the H2 yield was less when Ni/Al2O3 catalysts were employed. The amount of carbon deposited on each catalyst was measured. It was observed that the carbon depositions on the Ni/ZrO2 catalysts were extremely high. A comparison between the amounts of carbon deposited on the Ni/Al2O3 and Ni/ZrO2 catalysts revealed that the carbon deposition is strongly dependent on the type of support.

► Ni/ZrO2 catalysts are active for H2 production via steam reforming of bio-oil. ► The activity of the catalysts decreases gradually, due to severe carbon deposition. ► A potential H2 yield of 80% exists using a second step for water-gas-shift reaction.