Ammonia decomposition catalyst, honeycomb structure, and internal combustion engine
AssigneeMurata Manufacturing Co., Ltd.
InventorsSoichiro TSUJIMOTO, Yousuke SASAKI
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Abstract
An ammonia decomposition catalyst including a composite oxide forming a perovskite structure with at least barium, zirconium, and ruthenium. Also included is a honeycomb structure including the ammonia decomposition catalyst and an internal combustion engine including the ammonia decomposition catalyst. The ammonia decomposition catalyst exhibits excellent initial activity even at low temperatures and excellent heat resistance in terms of ammonia decomposition activity.
Claims20
An ammonia decomposition catalyst comprising a composite oxide forming a perovskite structure, wherein the ammonia decomposition catalyst comprises barium, zirconium, and ruthenium in amounts to satisfy (a), (b), and (c):
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- wherein MRu represents a number of moles of ruthenium contained in the composite oxide, MZr represents a number of moles of zirconium contained in the ammonia decomposition catalyst, and MBa represents a number of moles of barium contained in the ammonia decomposition catalyst.
A process for preparing an ammonia decomposition catalyst comprising:
- wet-mixing BaCO3, ZrO2, and RuO2 with cobblestones and water to obtain a mixture,
- drying and sizing the mixture to form a catalyst precursor powder, and
- calcining the catalyst precursor powder to provide an ammonia decomposition catalyst comprising a composite oxide forming a perovskite structure,
- wherein the ammonia decomposition catalyst comprises barium, zirconium, and ruthenium in amounts to satisfy (a), (b), and (c):
- 0.031
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- wherein MRu represents a number of moles of ruthenium contained in the composite oxide, MZr represents a number of moles of zirconium contained in the ammonia decomposition catalyst, and MBa represents a number of moles of barium contained in the ammonia decomposition catalyst.
Dependencies are inferred from the claim text.