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Influence of Magnesium Oxide on the Structure and Catalytic Activity of the Wustite Catalyst for Ammonia Synthesis.

ABSTRACT: The influence of a magnesium oxide admixture on the activation process and catalytic activity of the iron catalyst with a wustite structure was investigated during the ammonia synthesis reaction. The incorporation of magnesium oxide into wustite grains is considered to be a structure-forming and activating promoter. It stabilizes the α-Fe structure and increases the activity of the catalysts in the ammonia synthesis reaction. Moreover, magnesium oxide forms a solid solution with the wustite, which slows down the reduction of a catalyst precursor. Similar to calcium and potassium compounds, magnesium oxide is present on the α-Fe surface of the active form of the catalyst. The optimum MgO concentration in the catalyst structure was determined to be 1.2% wt.

SUBMITTER: Jurkowski A

PROVIDER: S-EPMC9739429 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature

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Influence of Magnesium Oxide on the Structure and Catalytic Activity of the Wustite Catalyst for Ammonia Synthesis.

Jurkowski Artur A Albrecht Aleksander A Moszyński Dariusz D Pelka Rafał R Lendzion-Bieluń Zofia Z

Materials (Basel, Switzerland) 20221123 23

The influence of a magnesium oxide admixture on the activation process and catalytic activity of the iron catalyst with a wustite structure was investigated during the ammonia synthesis reaction. The incorporation of magnesium oxide into wustite grains is considered to be a structure-forming and activating promoter. It stabilizes the α-Fe structure and increases the activity of the catalysts in the ammonia synthesis reaction. Moreover, magnesium oxide forms a solid solution with the wustite, whi ...[more]

PMID: 36499805

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