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Eutectic Phenomenon of LiNH₂-KH Composite in MH-NH₃ Hydrogen Storage System.

ABSTRACT: Hydrogenation of a lithium-potassium (double-cation) amide (LiK(NH₂)₂), which is generated as a product by ammonolysis of litium hydride and potassium hydride (LiH-KH) composite, is investigated in details. As a result, lithium amide (LiNH₂) and KH are generated after hydrogenation at 160 °C as an intermediate. It is noteworthy that the mixture of LiH and KNH₂ has a much lower melting point than that of the individual melting points of LiNH₂ and KH, which is recognized as a eutectic phenomenon. The hydrogenation temperature of LiNH₂ in the mixture is found to be significantly lower than that of LiNH₂ itself. This improvement of reactivity must be due to kinetic modification, induced by the enhanced atomic mobility due to the eutectic interaction.

SUBMITTER: Goshome K

PROVIDER: S-EPMC6479683 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Eutectic Phenomenon of LiNH₂-KH Composite in MH-NH₃ Hydrogen Storage System.

Goshome Kiyotaka K Jain Ankur A Miyaoka Hiroki H Yamamoto Hikaru H Kojima Yoshitsugu Y Ichikawa Takayuki T

Molecules (Basel, Switzerland) 20190405 7

Hydrogenation of a lithium-potassium (double-cation) amide (LiK(NH₂)₂), which is generated as a product by ammonolysis of litium hydride and potassium hydride (LiH-KH) composite, is investigated in details. As a result, lithium amide (LiNH₂) and KH are generated after hydrogenation at 160 °C as an intermediate. It is noteworthy that the mixture of LiH and KNH₂ has a much lower melting point than that of the individual melting points of LiNH₂ and KH, which is recognized as a eutectic phenomenon. ...[more]

PMID: 30959780

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