Thermodynamics of sulfur chemisorption on metals. III. Iron and cobalt

Journal Article · Thu Jan 14 23:00:00 EST 1982 · J. Chem. Phys.; (United States)

DOI:https://doi.org/10.1063/1.443085· OSTI ID:5690143

McCarty, J G; Wise, H

Isosteric heats of chemisorption of sulfur on iron and cobalt have been evaluated from measurements of the equilibrium ratio of H/sub 2/S/H/sub 2/ gas mixtures in contact with the powdered metals over a temperature range from 677 to 855 K. At low surface coverage of sulfur on cobalt, the heat of chemisorption with respect to 1/2 S/sub 2/(g) is -236 +- 15 kJ mol/sup -1/. With increasing coverage it decreases to -200 +- 10 kJ mol/sup -1/. The heat of sulfur chemisorption on iron is -197 +- 15 kJ mol/sup -1/. For equivalent coverage, the thermodynamic activity of sulfur chemisorbed on cobalt exceeds that of iron by approximately one order of magnitude. At low surface coverage (<0.5 saturation coverage), the bond strength of sulfur on the various metals is found to vary in the order: Ni>Co>Ru>Fe.

• Research Organization: Solid State Catalysis Laboratory, SRI International, Menlo Park, California 94025
• OSTI ID: 5690143
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 76:2; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical &amp; Physicochemical Properties
CHEMICAL BONDS
CHEMICAL REACTIONS
CHEMISORPTION
COBALT
ELEMENTS
IRON
METALS
NONMETALS
PHYSICAL PROPERTIES
SEPARATION PROCESSES
SORPTION
SORPTIVE PROPERTIES
SULFUR
SURFACE PROPERTIES
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENTS