Steam Reforming of n-Dodecane over Ru−Ni-Based Catalysts

Abstract

Steam reforming of n-dodecane has been carried out with the goal of development of new and highly active catalysts for hydrogen production. Newly designed RuO-NiO-CeO2-Al2O3 catalysts have been successfully prepared with various loadings of Ni by sol−gel method. X-ray diffraction (XRD), H2 TPD, BET surface area, temperature-programmed reduction (TPR), and temperature-programmed desorption of CO2 (TPD of CO2) were used to characterize the prepared catalysts. The coke formation was studied by temperature programmed oxidation (TPO). The reforming of n-dodecane was carried out in a microreactor and investigated at different reaction temperatures, space velocity, steam/carbon ratio, and time-on-stream. Characterization results reveal that the presence of Ru and CeO2 enhances the catalyst reducibility. H2 TPD and CO2 TPD data indicate that 1 wt % Ru/2.5 wt % Ni/3 wt % CeO2/Al2O3 (1R2.5N3CA) catalyst exhibits larger nickel surface area and higher basicity compared to all the other catalysts. The activity and hydrogen yield of the 1R2.5N3CA catalyst are significantly higher than those of the other nickel catalysts under the same experimental conditions. Catalytic stability is also enhanced by the presence of ruthenium in nickel catalysts. Such improvement indicates that ruthenium plays an important role in the catalytic action of nickel. Overall, the bimetallic 1R2.5N3CA may be an effective catalyst for the production of hydrogen from n-dodecane.