Reforming of isooctane over Ni-Al2O3 catalysts for hydrogen production:: Effects of catalyst preparation method and nickel loading

The production of hydrogen via the partial oxidation of isooctane was evaluated using a variety of Ni-Al2O3 catalysts(.) The effects of catalyst preparation method, nickel loading, and calcination temperature, as well as the reaction operating conditions (such as reaction temperature and space velocity), on the performance of the Ni-Al2O3 catalysts prepared were evaluated. These catalysts were thoroughly characterized to establish the relationship between catalyst characteristics and catalyst preparation conditions. Results showed that a high BET surface area enhances nickel dispersion, which, together with high catalyst reducibility, help to enhance the catalyst performance, in terms of isooctane conversion, H-2 selectivity, and turnover number (TON). In each preparation method, it was not possible to obtain high catalyst reducibility together with high nickel dispersion. Thus, the trends observed were manifestations of the opposing tendencies of these characteristics. Also, an increase in calcination temperature was determined to have a detrimental effect on catalyst performance and resulted in an increase in the amount of carbon deposited during the reaction.