Fe Nanocatalysts Supported on Dealuminated ZSM‐5 for Efficient Decomposition of Ammonia to COx‐Free Hydrogen

Abstract A series of dealuminated ZSM‐5 zeolite (deAlZSM‐5) supported Fe‐based catalysts are prepared by a modified solid‐state ion exchange method, in which the HZSM‐5 zeolite is dealuminated by concentrated HNO 3 and subsequently ground with ferric nitrate. The physicochemical properties of the resultant Fe/deAlZSM‐5 catalysts are characterized by XRD, N 2 sorption, TEM, H 2 ‐TPR and NH 3 ‐TPD techniques. It is revealed that the Fe species are highly dispersed in the deAlZSM‐5, and would be transformed into elemental Fe nanoparticles after reduction by H 2 . Due to the confinement effect of ZSM‐5 zeolite, the Fe/deAlZSM‐5 catalysts exhibit high catalytic activity and excellent stability for NH 3 decomposition. At 650 o C, about 100% NH 3 conversion can be achieved over the 9%Fe/deAlZSM‐5 catalysts for 50 h time‐on‐stream, demonstrating a very promising catalyst system in NH 3 decomposition.