Steam Gasification of a Cellulose Surrogate over a Fluidizable Ni/a-Alumina Catalyst: A Kinetic Model Enrique Salaices and Hugo de Lasa Chemical Reactor Engineering Centre, The University of Western Ontario, London, Ontario, Canada N6A5B8 Benito Serrano Programa Ingenieria Quimica, Universidad Autonoma de Zacatecas, Zacatecas, Mexico DOI 10.1002/aic.12696 Published online July 13, 2011 in Wiley Online Library (wileyonlinelibrary.com). Catalytic steam gasification of a cellulose surrogate using a fluidizable Ni/a-alumina catalyst is presented. Experiments were carried out in the CREC fluidized riser simula- tor. On this basis, a reaction network and a kinetic model for biomass catalytic steam gasification were proposed. This kinetic model was developed using a sound reaction engineering approach where reaction rates for various species are the result of the algebraic addition of dominant reactions. The modeling procedure also included the decoupled determination of intrinsic kinetic parameters and adsorption constants as allowed in the CREC riser simulator. The implemented approach eliminates overpara- metrization with successfully parameter correlation. Numerical regression of the exper- imental data led to intrinsic kinetic parameters with narrow spans showing that the proposed kinetic model satisfactorily describe the catalytic conversion of glucose under the selected gasification conditions. V VC 2011 American Institute of Chemical Engineers AIChE J, 58: 1588–1599, 2012 Keywords: kinetics, biomass, steam gasification, Ni/a-Al 2 O 3 catalyst Introduction Biomass steam gasification has become an area of growing interest because it produces a gaseous fuel with relatively higher hydrogen content that could be used for industrial applications, both for highly efficient electricity production and as a feedstock for chemical synthesis. Furthermore, steam gasification has other advantages in that (1) it produces a gas with higher heating value, (2) it reduces the diluting effect of N 2 from air, and (3) it eliminates the need for an expensive oxygen plant when both air and oxygen are used as gasifica- tion mediums. 1 Catalytic steam gasification of biomass in fluidized beds is a promising approach given its rapid biomass heating, its effective heat and mass transfer between reacting phases, and its uniform reaction temperature. 2 Moreover, flu- idized beds tolerate wide variations in fuel quality as well as broad particle-size distributions. The steam gasification of biomass is a complex network of heterogeneous reactions. Primary reactions break down the vaporized biomass molecules, forming coke and perma- nent gases C x H y O z þ x H 2 O ! heat a H 2 þ b CO þ c CO 2 þ w H 2 O þ 1C n H 2m þ XCðsÞ ð1Þ Secondary reactions crack the higher hydrocarbons into gases that further combust or become reduced C n H 2m þ nH 2 O ! nCO þðn þ mÞ H 2 (2) Correspondence concerning this article should be addressed to H. de Lasa at hdelas@ eng.uwo.ca. V VC 2011 American Institute of Chemical Engineers 1588 AIChE Journal May 2012 Vol. 58, No. 5