A model [gamma]-Al[sub 2]O[sub 3]-supported Re-Pt catalyst prepared from [Re[sub 2]Pt(CO)[sub 12]]

Journal Article · Mon Mar 01 04:00:00 EST 1993 · Journal of Catalysis; (United States)

DOI:https://doi.org/10.1006/jcat.1993.1078· OSTI ID:6305060

Fung, A S; McDevitt, M R; Tooley, P A; Gates, B C ^[1]; Kelley, M J ^[2]; Koningsberger, D C ^[3]

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1. Univ. of Delaware, Newark (United States)
2. E. I. du Pont de Nemours and Company, Wilmington, DE (United States)
3. Eindhoven Univ. of Technology (Netherlands) Univ. of Utrecht (Netherlands)

Catalysts supported on [gamma]-Al[sub 2]O[sub 3] were prepared from [Re[sub 2]Pt(CO)[sub 12]], and from Pt (NH[sub 3])[sub 4](NO[sub 3])[sub 2] and NH[sub 4]ReO[sub 4]. The former samples were characterized by infrared and X-ray photoelectron spectroscopies (XPS) and by temperature-programmed reduction (TPR); the latter were characterized by TPR. [Re[sub 2]Pt(CO)[sub 12]] was initially chemisorbed on the [gamma]-Al[sub 2]O[sub 3] surface. Upon treatment in H[sub 2] at about 150[degrees]C, the cluster fragmented and formed rhenium subcarbonyls, and at about 400[degrees]C the sample was decarbonylated. Adsorption of CO and of NO as probe molecules gave evidence of metallic Pt, but there was no evidence of adsorption on Re. The XPS data indicating the Re binding energies give evidence of the presence of low-valent cationic Re in the sample after the treatment at 400[degrees]C in H[sub 2]. In contrast, when a mixture of samples of Re on [gamma]-Al[sub 2]O[sub 3] and Pt on [gamma]-Al[sub 2]O[sub 3] prepared from [H[sub 3]Re[sub 3](CO)[sub 12]] and [(CH[sub 3])[sub 2]Pt(COD)], respectively, was treated under equivalent conditions, the Re was present in a high-valent cationic form (Re[sup 7+]), and Pt was metallic. It is concluded that Pt facilitated the reduction of Re and that Pt was likely near the rhenium in the sample prepared from [Re[sub 2]Pt(CO)[sub 12]]. The TPR data are consistent with the foregoing results. The TPR data characterizing the samples prepared from the metal salts show that the degree of hydroxylation of the [gamma]-Al[sub 2]O[sub 3] support significantly influenced the reduction of the Re and the Pt, but these data are not sufficient to determine the interactions between the two metals. 50 refs., 5 figs., 5 tabs.

• OSTI ID: 6305060
• Journal Information: Journal of Catalysis; (United States), Journal Name: Journal of Catalysis; (United States) Vol. 140:1; ISSN 0021-9517; ISSN JCTLA5
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020400 -- Petroleum-- Processing
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ABSORPTION SPECTROSCOPY
ADSORPTION
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CATALYST SUPPORTS
CATALYSTS
CHALCOGENIDES
CHEMICAL PREPARATION
CHEMICAL REACTIONS
ELECTRON SPECTROSCOPY
HYDROXYLATION
OXIDES
OXYGEN COMPOUNDS
PHOTOELECTRON SPECTROSCOPY
PLATINUM COMPOUNDS
REDUCTION
REFRACTORY METAL COMPOUNDS
RHENIUM COMPOUNDS
SALTS
SORPTION
SPECTROSCOPY
STRUCTURAL CHEMICAL ANALYSIS
SYNTHESIS
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE
TEMPERATURE RANGE 0273-0400 K
TEMPERATURE RANGE 0400-1000 K
TRANSITION ELEMENT COMPOUNDS
X-RAY SPECTROSCOPY