Mechanisms of the potassium stabilization in K2Fe22O34

• Autorzy: Trębala M.
• Języki publikacji: EN

Abstrakty

EN

Effect of potassium stabilization in K₂Fe₂₂O₃₄, the principal phase of styrene catalyst is caused by doping Cr and Ce. The effect was investigated by means of potassium ion and neutral atom thermal desorption. The kinetics for K⁺ and K emission from undoped and Ce-, Cr-doped b-K₂Fe₂₂O₃₄ is studied with the field reversal technique and steady-state mode in high vacuum conditions. Two main mechanisms of the stabilization were developed depending on the dopant location. Chromium is located in the structure of β-ferrite and slows down the diffusion potassium ion. Cerium segregated at the basal planes favoring the cationic state of potassium inhibits the probability of potassium atoms to leave the K₂Fe₂₂O₃₄ surface via work function increase.

Słowa kluczowe

EN

Potassium ferrite; Styrene catalyst; potassium lost; work function; potassium desorption

• Wydawca: Foundation for Young Scientists
• Czasopismo: Challenges of Modern Technology
• Rocznik: 2011
• Tom: Vol. 2, no. 2
• Strony: 43--45
• Opis fizyczny: Bibliogr. 12 poz., wykr.

Twórcy

autor

Trębala M.

• Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Cracow, Poland

Bibliografia

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