Catalytic significance of a Co-Mo-S phase in Co-Mo/Al/sub 2/O/sub 3/ hydrodesulfurization catalysts: combined in situ Moessbauer emission spectroscopy and activity studies

Wivel, C; Candia, R; Clausen, B S; Moerup, S; Topsoee, H

Title: Catalytic significance of a Co-Mo-S phase in Co-Mo/Al/sub 2/O/sub 3/ hydrodesulfurization catalysts: combined in situ Moessbauer emission spectroscopy and activity studies

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Abstract

A series of sulfided Co-Mo/Al/sub 2/O/sub 3/ catalysts with different Co/Mo ratios but with constant molybdenum content is investigated. The catalysts are characterized by in situ Moessbauer emission spectroscopy (MES) and investigated for their thiophene hydrodesulfurization activity. The catalytic activity shows a pronounced maximum at a Co/Mo ratio of about 1.0. The MES spectra reveal that cobalt may be present in three distinctly different phases: cobalt located in the alumina lattice (Co:Al/sub 2/O/sub 3/), cobalt in Co/sub 9/S/sub 8/, and cobalt located in the Co-Mo-S surface phase discussed in the preceeding paper. It is found that the relative amounts of the three phases depend strongly on the Co/Mo ratio. The Co:Al/sub 2/O/sub 3/ phase and the Co-Mo-S phase are observed in all catalysts studied, whereas Co/sub 9/S/sub 8/ is observed only in catalysts with Co/Mo > 0.4. It is shown that the presence of Co/sub 9/S/sub 8/ cannot explain the promoting role of cobalt in the Co-Mo/Al/sub 2/O/sub 3/ catalysts. However, a linear relation between the catalytic activity and the amount of Co in the Co-Mo-S phase leads to the conclusion that the promoting effect of cobalt is associated with the presence of this phase.

Authors:

Wivel, C ^[1]; Candia, R; Clausen, B S; Moerup, S; Topsoee, H

Technical Univ. of Denmark, Lyngby

Publication Date:: Wed Apr 01 00:00:00 EST 1981

OSTI Identifier:: 6414535

Resource Type:: Journal Article

Journal Name:: J. Catal.; (United States)

Additional Journal Information:: Journal Volume: 68:2

Country of Publication:: United States

Language:: English

Subject:: 02 PETROLEUM; COBALT; CATALYTIC EFFECTS; DESULFURIZATION; CATALYSTS; MOLYBDENUM; SULFIDES; ALUMINIUM OXIDES; CATALYSIS; EMISSION SPECTROSCOPY; PHASE STUDIES; ALUMINIUM COMPOUNDS; CHALCOGENIDES; CHEMICAL REACTIONS; ELEMENTS; METALS; OXIDES; OXYGEN COMPOUNDS; REFRACTORY METALS; SPECTROSCOPY; SULFUR COMPOUNDS; TRANSITION ELEMENTS; 020400* - Petroleum- Processing

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                    Wivel, C, Candia, R, Clausen, B S, Moerup, S, and Topsoee, H. Catalytic significance of a Co-Mo-S phase in Co-Mo/Al/sub 2/O/sub 3/ hydrodesulfurization catalysts: combined in situ Moessbauer emission spectroscopy and activity studies.  United States: N. p., 1981. 
        Web.

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                    Wivel, C, Candia, R, Clausen, B S, Moerup, S, & Topsoee, H. Catalytic significance of a Co-Mo-S phase in Co-Mo/Al/sub 2/O/sub 3/ hydrodesulfurization catalysts: combined in situ Moessbauer emission spectroscopy and activity studies.  United States.

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                    Wivel, C, Candia, R, Clausen, B S, Moerup, S, and Topsoee, H. 1981.  
        "Catalytic significance of a Co-Mo-S phase in Co-Mo/Al/sub 2/O/sub 3/ hydrodesulfurization catalysts: combined in situ Moessbauer emission spectroscopy and activity studies".  United States.

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@article{osti_6414535,

  title        = {Catalytic significance of a Co-Mo-S phase in Co-Mo/Al/sub 2/O/sub 3/ hydrodesulfurization catalysts: combined in situ Moessbauer emission spectroscopy and activity studies},

  author       = {Wivel, C and Candia, R and Clausen, B S and Moerup, S and Topsoee, H},

  abstractNote = {A series of sulfided Co-Mo/Al/sub 2/O/sub 3/ catalysts with different Co/Mo ratios but with constant molybdenum content is investigated. The catalysts are characterized by in situ Moessbauer emission spectroscopy (MES) and investigated for their thiophene hydrodesulfurization activity. The catalytic activity shows a pronounced maximum at a Co/Mo ratio of about 1.0. The MES spectra reveal that cobalt may be present in three distinctly different phases: cobalt located in the alumina lattice (Co:Al/sub 2/O/sub 3/), cobalt in Co/sub 9/S/sub 8/, and cobalt located in the Co-Mo-S surface phase discussed in the preceeding paper. It is found that the relative amounts of the three phases depend strongly on the Co/Mo ratio. The Co:Al/sub 2/O/sub 3/ phase and the Co-Mo-S phase are observed in all catalysts studied, whereas Co/sub 9/S/sub 8/ is observed only in catalysts with Co/Mo > 0.4. It is shown that the presence of Co/sub 9/S/sub 8/ cannot explain the promoting role of cobalt in the Co-Mo/Al/sub 2/O/sub 3/ catalysts. However, a linear relation between the catalytic activity and the amount of Co in the Co-Mo-S phase leads to the conclusion that the promoting effect of cobalt is associated with the presence of this phase.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/6414535},
  journal      = {J. Catal.; (United States)},
number       = ,

  volume       = 68:2,

  place        = {United States},

  year         = {Wed Apr 01 00:00:00 EST 1981},

  month        = {Wed Apr 01 00:00:00 EST 1981}

}

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