Hydrogen production by the decomposition of ammonia over Ru/Metal phosphate oxide catalyst

Abstract

Ammonia (NH3) is economical in hydrogen supply because the energy density per unit volume is high at 17.3 wt%. It is one of the candidates for hydrogen carriers. Ru, Ni, Co, and Cu-based catalysts have been studied in ammonia decomposition as active metals. Ru-based catalyst was mainly developed for commercial processes because of highly activity of Ru. In this study, Ru-based metal phosphate and oxide catalysts were investigated for the production of hydrogen by the decomposition of ammonia. Catalysts were prepared by precipitation and incipient impregnation method. The prepared catalysts were characterized by N2-physisorption, NH3-TPD, H2-TPR, and XRD analysis. The ammonia decomposition reaction was performed in a fixed bed reactor under 400 ~ 600 oC, 1 bar, and GHSV = 10,000 h-1. It was found that the MgO-based metal-oxide catalyst exhibited a higher ammonia conversion than the metal-phosphate-oxide catalyst.