Nickel catalysts supported on Al2O3, CeO2 and ZrO2 were prepared by wet
impregnation method and evaluated in steam reforming of glycerol. The
catalysts were characterized by chemical composition, textural analysis,
crystalline structure and reducibility. The structural characterization of the
catalysts revealed a good dispersion of Ni particles using the Al2O3 support,
needing higher reduction temperature. The reactions were performed
at 500°C with 10 vol.% glycerol solution in a continuous flow reactor.
All catalysts showed conversions close to 100%. The selectivity to gas
products and formation of liquid by-products were found to be dependent
on the type of support. The H2 selectivity showed the following trend: ZrO2 > Al2O3 ≈ CeO2. The catalyst supported on CeO2 showed low activity
for water-gas shift reaction, with the highest CO selectivity. All catalysts
presented a low formation of CH4. In the liquid phase some by-products
were identified (hydroxyacetone, acetic acid, lactic acid, acetaldehyde,
acrolein and ethanol) and secondary reaction routes were proposed.
Coke formation was higher on Ni/Al2O3 catalyst, but no deactivation was
observed during 8 h of reaction.