NMR study of the influence of adsorbed sulfur on hydrogen chemisorption on supported ruthenium catalysts

Journal Article · Wed Apr 01 04:00:00 EST 1992 · Journal of Catalysis; (United States)

DOI:https://doi.org/10.1016/0021-9517(92)90343-G· OSTI ID:6976279

Bhatia, S; Gerstein, B C; King, T S ^[1]

---

1. Iowa State Univ., Ames (United States) Ames Lab., IA (United States)

NMR of hydrogen chemisorbed on silica-supported ruthenium catalysts was used to study the dissociation of H[sub 2]S and its effect on subsequent hydrogen adsorption. A mixture of H[sub 2]S/He was used to sulfide the reduced catalyst. The hydrogen coverages resulting from the dissociation of H[sub 2]S as measured by NMR yielded estimates of sulfur coverages in good agreement with the results of X-ray fluorescence analysis of sulfur on the samples. The H[sub 2]S dissociation reaction was found to be enhanced on higher dispersion catalysts suggesting an important role for defect-like sites. At sulfur coverages greater than 0.25 sulfur atoms per surface ruthenium atom, no hydrogen from the dissociation of H[sub 2]S could be detected remaining on the surface. On the presulfided catalysts dosed to saturation with additional hydrogen, the NMR spectra revealed the presence of two species of hydrogen: a mobile species and a less mobile species. At sulfur coverages greater than 0.5 no detectable hydrogen could be adsorbed on the surface when exposed to 30 Torr of H[sub 2]. The ratio of weakly bound hydrogen at saturation coverage decreased with increasing sulfur coverage. The small change in the magnitude of the NMR lineshift of hydrogen-on-metal with sulfur coverage suggested that the adsorbed sulfur does not induce a strong electronic effect on the chemisorption of hydrogen.

• OSTI ID: 6976279
• Journal Information: Journal of Catalysis; (United States), Journal Name: Journal of Catalysis; (United States) Vol. 134:2; ISSN 0021-9517; ISSN JCTLA5
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ADSORPTION
CATALYST SUPPORTS
CATALYSTS
CATALYTIC EFFECTS
CHALCOGENIDES
CHEMICAL ANALYSIS
CHEMICAL REACTIONS
CHEMISORPTION
DISPERSIONS
DISSOCIATION
ELEMENTS
FLUIDS
GASES
HELIUM
HYDROGEN
HYDROGEN COMPOUNDS
HYDROGEN SULFIDES
MAGNETIC RESONANCE
METALS
MIXTURES
NONDESTRUCTIVE ANALYSIS
NONMETALS
NUCLEAR MAGNETIC RESONANCE
OXIDES
OXYGEN COMPOUNDS
PLATINUM METALS
POISONING
RARE GASES
RESONANCE
RUTHENIUM
SEPARATION PROCESSES
SILICON COMPOUNDS
SILICON OXIDES
SORPTION
SORPTIVE PROPERTIES
SULFIDES
SULFUR
SULFUR COMPOUNDS
SURFACE PROPERTIES
TRANSITION ELEMENTS
X-RAY EMISSION ANALYSIS
X-RAY FLUORESCENCE ANALYSIS