Barium oxide as a modifier to stabilize the γ-Al2O3 structure

• Autorzy: Pakdeh S. G. , Rasoolzadeh M. , Moghadam A. S.

Identyfikatory

DOI

10.1515/pjct-2016-0062

• Języki publikacji: EN

Abstrakty

EN

This research concentrated on the structural stability of γ-alumina (γ-Al₂O₃ ) was investigated by a combination of differential thermal analysis, X-ray diffractometry and surface-area measurements. The γ –to– θ and then α phase transitions were observed as an exothermic peak at 1000°C–1400°C in the DTA curves. The role of barium oxide as a modifier to stabilize γ-Al₂O₃  structure has been investigated. XRD measurements show that after calcination at 1000°C for 2 h, a significant fraction of the pure γ-Al₂O₃  (BaO-free) transformed to θ-Al₂O₃  while that the transition phase in alumina samples modified by BaO have been reduced significantly. Barium oxide, eliminate pentacoordinated aluminum ions through coordinative saturation and alter these ions into octahedral cations and effectively suppressed the γ –to– α phase transition in Al₂O₃ , which concluded as improving the thermal stability and porous properties of the experimental samples.

Słowa kluczowe

EN

γ-Al2O3; thermal stability; phase transition; barium oxide; pentacoordinated Al3+ ions

• Wydawca: West Pomeranian University of Technology. Publishing House
• Czasopismo: Polish Journal of Chemical Technology
• Rocznik: 2016
• Tom: Vol. 18, nr 4
• Strony: 1--4
• Opis fizyczny: Bibliogr. 20 poz., rys., tab.

Twórcy

autor

Pakdeh S. G.

• Malek-Ashtar University of Technology, Faculty of Chemistry and Chemical Engineering, Tehran, Iran (Islamic Republic of Iran)

autor

Rasoolzadeh M.

• Malek-Ashtar University of Technology, Faculty of Chemistry and Chemical Engineering, Tehran, Iran (Islamic Republic of Iran)

autor

Moghadam A. S.

• Malek-Ashtar University of Technology, Faculty of Chemistry and Chemical Engineering, Tehran, Iran (Islamic Republic of Iran)

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Uwagi

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę (zadania 2017).