Effective hydrogen production from partial oxidation of propane over composite Ni/Al2O3[sbnd]SiC catalyst

Abstract

In this work, hydrogen production from partial oxidation (POX) of propane over composite Ni/Al2O3SiC catalyst was investigated. In order to utilize the high thermal conductivity and chemical stability of SiC, the composite Al2O3SiC support of the catalyst was synthesized by precipitation technique, then Ni component was loaded using impregnation method. The as-prepared samples were characterized by X-ray diffraction, BET, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) measurements. As observed, stacking porous structures were appeared after calcination process by doping SiC with certain ratios. According to the stiochiometric ratio, a C3H8O2 (1:1.5) gas mixture was used to study the catalytic activity for hydrogen production from POX of propane. From the results, local overheat of the catalyst bed generated by the exothermic reactions was relieved by doping SiC and Ni/Al2O3SiC (30 wt%) catalyst performed a higher hydrogen production. Aggregation and carbon deposition of Ni/Al2O3SiC (30 wt%) catalyst were reduced compared to Ni/Al2O3 from the observation of SEM and TEM with H2 production up to around 236 μmol/gcat·s and kept stable for 26 h at 600 °C. By means of TGA, non-isothermal oxidative decarburizations of the spent catalysts were studied. It was found that less carbon deposit and lower activation energy for oxidative decarburization were found by doping SiC to Ni/Al2O3.