Steam methane reforming in a Ni/Al₂O₃ catalyst: Kinetics and diffusional limitations in extrudates

Abstract

The true kinetics of methane steam reforming was measured in powder of Ni/Al 2 O 3 catalyst ("Octolyst 1001" from Degussa) at different temperatures (733-890 K) for several operating conditions. New reaction rate constants were determined for this catalyst. The observed reaction rate was measured on catalyst extrudates to determine diffusion effects within the porous structure of the particle. A non-isothermal model with diffusion was used to determine effectiveness factors for each reaction. The objective was to measure all necessary data to model the performance of the catalyst in a Sorption Enhanced Reaction Process (SERP) for H 2 production with in situ CO 2 capture.On a mesuré la cinétique réelle du reformageà la vapeur de méthane sur un catalyseur Ni/Al 2 O 3 sous forme de poudre (« Octolyst 1001 » de Degussa)à différentes températures (733-890 K) dans plusieurs conditions d'exploitation. De nouvelles constantes de vitesse de réaction ontété déterminées pour ce catalyseur. On a mesuré la vitesse de réaction observée sur des extrudats de catalyseur pour déterminer les effets de diffusioǹ a l'intérieur de la structure poreuse de la particule. On a utilisé un modèle non isothermique avec diffusion pour déterminer les facteurs d'efficacité de chaque réaction. L'objectif consistaità mesurer toutes les données nécessaires pour modéliser la performance du catalyseur dans un procédé de réaction améliorée de sorption pour la production de H 2 avec captage in-situ de CO 2 .

Methane steam reforming in large pore catalyst

“…The temperature decrease is more pronounced in the initial section of the catalyst bed where the 6. Comparison between the carbon dioxide selectivity ðS CO2 Þ and hydrogen yield ðY H2 Þ using the catalyst in this work and the commercial catalyst from Degussa (Oliveira et al, 2009). Results obtained with the catalysts in powder form.…”

A numerical study of fixed bed reactor modelling for steam methane reforming process

“…It is found that the velocity across the pellet is zero. The pressure has been calculated from Darcy's law, i.e., Equation (32). So, the pressure gradient is directly proportional to the velocity.…”

“…Furthermore, the possibility of negative or asymptotic values of effectiveness factor cannot be ruled out for the SMR process. [7,25,29,31,32] Stutz et al [33] and Parisi and Laborde [34] have studied the catalytic surface reaction for the steam methane reforming reaction. Lutz et al [35] and Jannelli et al [36] have investigated the steam reforming system using the thermodynamic equilibrium state.…”

Characterization and activity test of commercial Ni/Al2O3, Cu/ZnO/Al2O3 and prepared Ni–Cu/Al2O3 catalysts for hydrogen production from methane and methanol fuels

“…It is clear from Fig. 2(a)-(c) that each catalyst has its own metal clusters on the support with various sizes [35].…”