Partial fluorination of ?-alumina by gaseous fluorine
Por:
Saniger J.M., Sánchez N.A., Flores J.O.
Publicada:
1 ene 1998
Resumen:
Fluorination of ?-alumina samples with 100 and 300 mbar of undiluted gaseous fluorine at room temperature, results in the incorporation of 3.0% ( sample a) and 6.7% in weight (sample b) of fluorine, respectively. The fluorinated samples were studied by XRD and FT-IR. The X-ray diffractograms show no significant changes for sample a and the formation of a second phase of aluminum hydroxyfluoride for sample b. Infrared spectra of the hydroxyl region show important modifications of the OH bands: for sample a, the removal of the OH groups of basic character can be observed, as well as the near disappearance of the hydrogen bond interaction among other OH groups; on the other hand, sample b presents a new strong and sharp band related to the OH groups of the aluminum hydroxyfluoride phase. The deconvolution analysis of the Al-O vibration region, for sample b, allows the identification of new bands associated with the aluminum hydroxyfluoride phase. The spl tting of the former Al-O bands of the ?-alumina is attributed to the loss of symmetry of the polyhedral AlO4 and AlO6 groups due to the O/F substitution. © 1998 Elsevier Science S.A. All rights reserved.
Filiaciones:
Saniger J.M.:
Lab. de Química de Materiales, Centro de Instrumentos, Univ. Nac. Autonoma de Mexico, Apdo. Postal 70-186, México D.F. 04510, Mexico
Sánchez N.A.:
Lab. de Química de Materiales, Centro de Instrumentos, Univ. Nac. Autonoma de Mexico, Apdo. Postal 70-186, México D.F. 04510, Mexico
Flores J.O.:
Lab. de Química de Materiales, Centro de Instrumentos, Univ. Nac. Autonoma de Mexico, Apdo. Postal 70-186, México D.F. 04510, Mexico
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