Contribution à l’étude par spectroscopie infrarouge et RMN large bande des hydroxydes d’aluminium : gibbsite, bayerite, nordstrandite

Vivien, D.; Stegmann, Marie-Cécile; Mazières, C.

doi:10.1051/jcp/1973701502

Cited by 23 publications

(7 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Bayerite and gibbsite were prepared from sodium aluminate solution as described elsewhere 5 and were identified by x-ray diffraction as the˛-and -phases, respectively, of Al(OH) 3 with no other phases detected.…”

Section: Methodsmentioning

confidence: 99%

UV Raman spectroscopic study of hydrogen bonding in gibbsite and bayerite between 93 and 453 K

Rzhevskii¹,

Ribeiro²

2001

J Raman Spectroscopy

View full text Add to dashboard Cite

Raman spectra of bayerite and gibbsite (hydrargillite) were measured at 453, 295 and 93 K and after H-D exchange at 423 K with gaseous D 2 O. Spectra in the O-H stretching vibration region were recorded with the use of ultraviolet laser excitation, which avoided the fluorescence problem typical for these materials. Lowering the temperature led to a spectral resolution improvement with additional bands resolved in the n(OH) spectrum of bayerite. It was established that the positions of the Raman bands are sensitive to the temperature of the sample. A spectral criterion based on different shifts of band positions with temperature was proposed as a method to distinguish between structural OH groups forming H-bonds between hydroxide layers or in the same plane of the layer. It was found that the highest wavenumber band at 3655 cm −1 in the spectrum of bayerite does not participate in H-bonding. A one-to-one correspondence between Raman spectra recorded in the n(OH) and n(OD) regions upon partial H-D exchange with D 2 O is evidence that the multiplicity of spectral bands is caused by different O-H· · ·O distances in the hydroxide lattice rather than by vibrational coupling of H-bonded hydroxyls.

show abstract

Section: Methodsmentioning

confidence: 99%

UV Raman spectroscopic study of hydrogen bonding in gibbsite and bayerite between 93 and 453 K

Rzhevskii¹,

Ribeiro²

2001

J Raman Spectroscopy

View full text Add to dashboard Cite

show abstract

“…Both IR [57,[60][61][62][63] and UV-Raman spectroscopy [60,[64][65][66][67] are able to identify the aluminum hydroxide phases due to differences in the hydroxyl stretching region. The results of our own measurements are shown in Fig.…”

Section: Spectroscopymentioning

confidence: 99%

Dissolution kinetics of nanodispersed γ-alumina in aqueous solution at different pH: Unusual kinetic size effect and formation of a new phase

Roelofs

Vogelsberger

2006

Journal of Colloid and Interface Science

View full text Add to dashboard Cite

“…The two weak bands located at 1094 and 991 cm -1 look more interesting in this respect. In aluminum hydroxides, 25 which contain Al(OH) 6 octahedra, and in metallic hydroxo salts of the M(OH) 6 type 26 (e.g., K 2 Pt(OH) 6 ), bands between 900 and 1200 cm -1 have been assigned to OH bending vibrations (δ OH ). Furthermore, Fuchs and Bru ¨dgam 23 studied a series of protonated Anderson-type heteropolymolybdates of general formula [M(OH) 6 Mo 6 O 18 ] x-(M ) Fe 3+ , Al 3+ , Ni 2+ , Cu 2+ ...).…”

Section: Characterization Of the Reference Heteropolyanion K 3 [Al(oh...mentioning

confidence: 99%

Ligand-Promoted Alumina Dissolution in the Preparation of MoO_X/γ-Al₂O₃ Catalysts: Evidence for the Formation and Deposition of an Anderson-type Alumino Heteropolymolybdate

1997

View full text Add to dashboard Cite

The deposition of Mo on γ-alumina by the equilibrium adsorption method starting from ammonium heptamolybdate has been studied. Spectroscopic results converge to indicate that a previously unrecognized species, i.e., the Anderson-type heteropolymolybdate [Al(OH)6Mo6O18]3-, plays a major role in this type of synthesis as it is quantitatively formed in the solution within a few hours, by reaction of the heptamolybdate with dissolved aluminic species. This results in a considerable increase of alumina solubility in conditions generally thought to be nonaggressive. Furthermore, this species is also present in the solid catalyst after deposition, although it is harder to observe than in the liquid phase. A parallel is drawn with a well-known idea from the field of geochemistry, i.e., ligand-promoted oxide dissolution. The relevance of this phenomenon in catalyst preparation is evaluated in realistic conditions corresponding to published studies and/or industrial procedures. It is concluded that strong metal−support interaction in the deposition stage by surface dissolution followed by reaction in the liquid phase is most likely to be an important phenomenon, not only for cationic metal precursors as previously known but also for anionic precursors such as molybdates.

show abstract

Contribution à l’étude par spectroscopie infrarouge et RMN large bande des hydroxydes d’aluminium : gibbsite, bayerite, nordstrandite

Cited by 23 publications

References 0 publications

UV Raman spectroscopic study of hydrogen bonding in gibbsite and bayerite between 93 and 453 K

UV Raman spectroscopic study of hydrogen bonding in gibbsite and bayerite between 93 and 453 K

Dissolution kinetics of nanodispersed γ-alumina in aqueous solution at different pH: Unusual kinetic size effect and formation of a new phase

Ligand-Promoted Alumina Dissolution in the Preparation of MoO_X/γ-Al₂O₃ Catalysts: Evidence for the Formation and Deposition of an Anderson-type Alumino Heteropolymolybdate

Contact Info

Product

Resources

About

Contribution à l’étude par spectroscopie infrarouge et RMN large bande des hydroxydes d’aluminium : gibbsite, bayerite, nordstrandite

Cited by 23 publications

References 0 publications

UV Raman spectroscopic study of hydrogen bonding in gibbsite and bayerite between 93 and 453 K

UV Raman spectroscopic study of hydrogen bonding in gibbsite and bayerite between 93 and 453 K

Dissolution kinetics of nanodispersed γ-alumina in aqueous solution at different pH: Unusual kinetic size effect and formation of a new phase

Ligand-Promoted Alumina Dissolution in the Preparation of MoOX/γ-Al2O3 Catalysts: Evidence for the Formation and Deposition of an Anderson-type Alumino Heteropolymolybdate

Contact Info

Product

Resources

About

Ligand-Promoted Alumina Dissolution in the Preparation of MoO_X/γ-Al₂O₃ Catalysts: Evidence for the Formation and Deposition of an Anderson-type Alumino Heteropolymolybdate