Hydrogen generation by ammonia cracking with iron metal-rare earth oxide composite catalyst

Abstract

A series of fine powders of Fe-MOx (M = Ce, Al, Si, Sr, and Zr) composite were prepared by the conventional coprecipitation method from their nitrate solutions. The activity of hydrogen extraction from ammonia over these composite powders as ammonia cracking catalyst was characterized. The catalytic activity for ammonia decomposition observed on the composite powders of Fe-(Ce, Zr)O2 was high because of the electron donation to the iron metal from Ce3+ due to the reduction of CeO2 through the reaction. In addition to this effect, the additive (Ce, Zr)O2 solid solution supports worked as a solid acid to enhance the ammonia adsorption and reaction probability of Fe component. These were effective to generate hydrogen through the ammonia decomposition at relatively low temperature.