Development of a Ru catalyst supported on HY zeolite for the oxidative decomposition of NH3 triggered at room temperature.

On-site hydrogen production from the oxidative decomposition of NH 3 with a catalyst is highly required in the countryside where external heat is hardly supplied. In this study, Ru-based zeolite catalysts were prepared by impregnation and subsequent washing using RuCl 3 ·3H 2 O and HY zeolite or H-MOR zeolite for the oxidative decomposition of NH 3. The H-MOR-supported Ru catalyst could not be self-heated by feeding 80% NH 3 /20% O 2 to the catalyst bed at room temperature. By contrast, the HY-supported Ru catalyst underwent self-heating to approximately 773 K upon feeding the reactants owing to the heat released by NH 3 adsorption and oxidation, leading to excellent performance for the oxidative decomposition of NH 3 during five cycles of start-up tests. Characterization results indicated that the Cl-free Ru/HY catalyst exhibited self-heating due to the presence of small well-dispersed Ru metal particles and a large amount of surface acidic sites. [Display omitted] • HY or H-MOR zeolite was selected as a support for Ru-based zeolite catalysts. • Cl-free Ru/HY catalyst underwent self-heating to approximately 773 K upon feeding 80%NH 3 /20%O 2. • Cl species presented on the catalyst was needed for self-heating of Ru/H-MOR catalyst bed. • Cl-free Ru/HY catalyst exhibited stable catalytic activity during five start-up cycles. • This attributes to the presence of small well-dispersed Ru particles and a large amount of acid sites. [ABSTRACT FROM AUTHOR]