BROWNMILLERITE HYDRATION BY MOESSBAUER SPECTROMETRY.

A. Vértes, M. Ranogajec-Komor, F. Tamas

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

The hydration of brownmillerite and of S54-blend (sulphate resistant) cement was studied by Moessbauer spectrometry and X-ray diffraction. Hydration (in the interval 0-100 days) was made in the presence and absence of Ca(OH)//2 and at 25 and 2 degree C. The Moessbauer spectra were taken at liquid nitrogen temperature. Anhydrous brownmillerite shows a magnetic hyperfine structure, which disappears after hydration. The hydrated samples usually have a considerable quadrupole splitting, indicating that the charge distribution around the iron atoms is asymmetric. However, brownmillerite samples hydrated at 25 degree C in the presence of excess Ca(OH)//2 have no quadrupole splitting, i. e. , the charge distribution around iron atoms is very symmetric in this case; but even in these samples the X-ray pattern shows the presence of both cubic and hexagonal phases. This means that the hexagonal hydrate is iron-free: iron atoms preferentially occupy the lattice sites of the cubic phase. The addition of magnesium sulphate removes iron atoms from this symmetric condition. The relatively low iron content makes the determination of Moessbauer parameters difficult in hydrated cement.

Original languageEnglish
Pages (from-to)339-346
Number of pages8
JournalHungarian Journal of Industrial Chemistry
Volume3
Issue number2
Publication statusPublished - 1975

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Hydration
Spectrometry
Iron
Atoms
Charge distribution
Cements
Magnesium Sulfate
Magnetic structure
Liquid nitrogen
Hydrates
Sulfates
Magnesium
X ray diffraction
X rays
Temperature

ASJC Scopus subject areas

  • Chemical Engineering(all)
  • Chemistry(all)
  • Chemistry (miscellaneous)

Cite this

BROWNMILLERITE HYDRATION BY MOESSBAUER SPECTROMETRY. / Vértes, A.; Ranogajec-Komor, M.; Tamas, F.

In: Hungarian Journal of Industrial Chemistry, Vol. 3, No. 2, 1975, p. 339-346.

Research output: Contribution to journalArticle

Vértes, A, Ranogajec-Komor, M & Tamas, F 1975, 'BROWNMILLERITE HYDRATION BY MOESSBAUER SPECTROMETRY.', Hungarian Journal of Industrial Chemistry, vol. 3, no. 2, pp. 339-346.
Vértes, A. ; Ranogajec-Komor, M. ; Tamas, F. / BROWNMILLERITE HYDRATION BY MOESSBAUER SPECTROMETRY. In: Hungarian Journal of Industrial Chemistry. 1975 ; Vol. 3, No. 2. pp. 339-346.
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