Hydrogen Production by Catalytic Steam Reforming of Acetol, a Model Compound of Bio-Oil

Abstract

Hydrogen can be produced by catalytic steam reforming of bio-oil or its fractions. Bio-oil is a complex mixture of a large number of compounds derived from fast pyrolysis of biomass. Acetol has been selected as a model compound. Steam reforming of acetol has been studied in a fluidized bed reactor using coprecipitated Ni−Al catalysts, some promoted with lanthanum and cobalt. Noncatalytic experiments have been performed from 450 to 650 °C. Catalytic experiments have been carried out at 600 and 650 °C in order to analyze the influence of the catalyst weight/acetol flow rate (W/mAc) ratio on gas yields. The influence of the steam to carbon molar (S/C) ratio and the catalyst composition on gas yields has also been studied. The presence of the catalyst increases H2, CO2, and total gas yields while CH4, CO, and C2 yields decrease. An increase in the S/C ratio at 650 °C increases H2, CO2, and total gas yields and carbon conversion to gas. The presence of lanthanum in Ni−Al coprecipitated catalysts increases CH4, CO2, C2, and total gas yields as well as carbon conversion to gas. Ni−Co−Al catalysts present the lowest values of carbon conversion to gas. Hydrogen yields obtained with the catalysts tested follow this sequence: Ni−Al = Ni−Co−Al (Co/Ni = 0.25) > Ni−Co−Al (Co/Ni = 0.025) > Ni−Al−La (4 wt % La2O3) > Ni−Al−La (8 wt % La2O3) > Ni−Al−La (12 wt % La2O3).