Catalytic steam reforming of bio-oil is a promising process for hydrogen production from biomass. Bio-oil is a complex mixture of a large number of compounds (acids, aldehydes, alcohols, and ketones, among other compounds), and acetic acid has been selected as a model compound. The experimental work has been conducted in a fluidized-bed reactor. Noncatalytic steam reforming of acetic acid has been performed from 450 °C to 700 °C. For catalytic experiments, coprecipitated Ni-Al catalysts, some promoted with lanthanum, have been selected, because of their high mechanical strength and suitable performance in biomass steam gasification. The presence of the catalyst, its reduction, promotion with lanthanum, and the influence of space velocity on gas yields have been analyzed at 650 °C. Catalytic experiments show a significant increase in total gas, H 2 , and CO 2 yields, whereas CH 4 and C 2 yields decrease, when compared with those from noncatalytic experiments. Gas yields obtained in the catalytic process present a shift from the noncatalytic process to equilibrium gas yields. Promotion with lanthanum does not increase the H 2 yield achieved with the Ni-Al catalyst. Simple first-order kinetic equations have been proposed for the formation of H 2 and CO 2 and the disappearance of CH 4 and C 2 .

Capillary column inverse gas chromatography experiments at infinite solvent dilution were conducted for 15 polyethylene/solvent systems. Thermodynamic data were collected for various types of penetrant molecules (normal alkanes, 1-alkenes, isomers of hexane, and ring compounds). Theoretical predictions of the solubility data were made with an activity coefficient model (Universal Functional Group Activity-van der Waals-Free-Volume) (UNIFAC-vdw-FV) and an equation-of-state model (GroupContribution, Lattice-Fluid, Equation of State) (GCLF-EoS). Although good agreement between the experimental data and theoretical predictions was obtained above the melting point of the polymer, at temperatures below the melting point, significant differences were found. This occurred because at those temperatures, the polymer had a semicrystalline structure and the solubility of the solvent was reduced on account of the constraints on some of the chains in the amorphous phase by the polymer crystallites. The theory developed by Michaels and Hausslein to account for such elastic effects on solubility was incorporated into the two predictive models. After these modifications, the new estimations of the solubility showed significantly improved agreement with the experimental results. Moreover, the elasticity effect resulted in elevated estimates of the crystallinity when inverse gas chromatography retention volumes were used.

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