Performance and Controlling Regimes Analysis of Methane Steam Reforming on Ru/γ-Al2O3 Cordierite Monoliths

In the frame of methane steam reforming (MSR) process intensification for H2 production, catalysts based on ruthenium (Ru) supported on alumina (Al2O3) on cordierite monolith have been studied in terms of catalytic performance, mass and heat transfer effects. Firstly, we compared the catalytic activity of Ru and Rh supported catalysts. Secondly, we study the effect of catalyst loading by varying the amount of carrier and active metal phase corresponding to 3.20, 6.45 and 12.89 mg cm−2. Then, we evaluated the mass/heat transfer effects and controlling regimes for the best-selected catalyst. Finally, the best-selected catalyst was characterized by means of Brunauer–Emmet–Teller (BET), X-ray diffraction analysis (XRD) and Fieldemission scanning electron microscopy (FESEM). The experiments were carried out in the temperature range of 550–850 °C, steam-to-carbon molar ratio (S/C) of 3.0 and different weight hourly space velocity (WHSV = 750, 1500 and 3000 Nl h−1 gcat−1). The catalyst with 1.5% Ru on 10% Al (1.5Ru10Al) was found to be the most promising toward the MSR reaction in terms of CH4 conversion and H2 production. This catalyst operates in a mixed regime for all temperature range studied, in which both the kinetic and the intraparticle diffusion co-exist. For the 1.5Ru10Al catalyst, the external thermal effects are important a temperature below 725 °C, while that intraparticle heat effects are absent for all the range of temperature studied. An excellent stability of the 1.5Ru10Al catalyst was observed over 70 h of time on stream (TOS) for MSR process.