Surface spectroscopic characterization of the interaction between zinc ions and. gamma. -alumina

Journal Article · Sun Apr 01 04:00:00 EST 1984 · J. Catal.; (United States)

DOI:https://doi.org/10.1016/0021-9517(84)90372-5· OSTI ID:7204963

Strohmeier, B R; Hercules, D M

Interaction of zinc ions with ..gamma..-alumina has been investigated using the surface spectroscopic techniques of X-ray photoelectron spectroscopy (ESCA or XPS) and low energy ion scattering spectroscopy (ISS). In addition, the bulk techniques of laser Raman spectroscopy (LRS) and X-ray diffraction (XRD) were employed. Surface characteristics of Zn/Al/sub 2/O/sub 3/ catalysts are affected by both metal loading and calcination temperature. The Zn/Al intensity ratio was examined as a function of zinc content and calcination temperature. Plots of both ESCA and ISS intensity ratios (Zn/Al) vs metal loading show changes in slope at high loadings, indicating a change in surface structure. ESCA, LRS, and XRD all show the ability to distinguish between ZnO and ZnAl/sub 2/O/sub 4/. Results indicate that at low zinc loadings (<20%), a strong interaction occurs between zinc and ..gamma..-alumina resulting in the formation of an aluminate type phase (i.e., a surface spinel). This interaction involves diffusion of zinc ions into the tetrahedral lattice sites of the support. At higher loadings, bulk-like ZnO segregates on top of the interaction species and the support. ESCA has also been used to study the effects of reduction and sulfiding on the catalysts.

• Research Organization: Univ. of Pittsburgh, PA
• OSTI ID: 7204963
• Journal Information: J. Catal.; (United States), Journal Name: J. Catal.; (United States) Vol. 86:2; ISSN JCTLA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical &amp; Physicochemical Properties
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CATALYSTS
CHALCOGENIDES
CHARGED PARTICLES
CHEMICAL ANALYSIS
COHERENT SCATTERING
DIFFRACTION
ION SCATTERING ANALYSIS
IONS
NONDESTRUCTIVE ANALYSIS
OXIDES
OXYGEN COMPOUNDS
SCATTERING
SPECTROSCOPY
STRUCTURAL CHEMICAL ANALYSIS
X-RAY DIFFRACTION
X-RAY SPECTROSCOPY
ZINC IONS