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Ammonia decomposition catalysis using non-stoichiometric lithium imide.

ABSTRACT: We demonstrate that non-stoichiometric lithium imide is a highly active catalyst for the production of high-purity hydrogen from ammonia, with superior ammonia decomposition activity to a number of other catalyst materials. Neutron powder diffraction measurements reveal that the catalyst deviates from pure imide stoichiometry under ammonia flow, with active catalytic behaviour observed across a range of stoichiometry values near the imide. These measurements also show that hydrogen from the ammonia is exchanged with, and incorporated into, the bulk catalyst material, in a significant departure from existing ammonia decomposition catalysts. The efficacy of the lithium imide-amide system not only represents a more promising catalyst system, but also broadens the range of candidates for amide-based ammonia decomposition to include those that form imides.

SUBMITTER: Makepeace JW

PROVIDER: S-EPMC5707451 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Ammonia decomposition catalysis using non-stoichiometric lithium imide.

Makepeace Joshua W JW Wood Thomas J TJ Hunter Hazel M A HMA Jones Martin O MO David William I F WIF

Chemical science 20150507 7

We demonstrate that non-stoichiometric lithium imide is a highly active catalyst for the production of high-purity hydrogen from ammonia, with superior ammonia decomposition activity to a number of other catalyst materials. Neutron powder diffraction measurements reveal that the catalyst deviates from pure imide stoichiometry under ammonia flow, with active catalytic behaviour observed across a range of stoichiometry values near the imide. These measurements also show that hydrogen from the ammo ...[more]

PMID: 29218150

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