Source:http://linkedlifedata.com/resource/pubmed/id/16851015
Switch to
| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
1
|
| pubmed:dateCreated |
2006-7-20
|
| pubmed:abstractText |
The elucidation of a molecular structure of the active sites (i.e., the Co-Mo-S phase) of Co-Mo hydrodesulfurization catalysts has received extensive attention. In the present study, we unambiguously determined, for the first time, the NO adsorption behavior and magnetic property of the Co-Mo-S phase by preparing unique Co-Mo/Al(2)O(3) catalysts (CVD-Co/MoS(2)/Al(2)O(3)), in which all the Co atoms are present as the Co-Mo-S phase. The catalysts were characterized by NO adsorption (pulse technique and FTIR), Co K-edge XANES, and the magnetic susceptibility and effective magnetic moment of Co. Nitric oxide molecules were adsorbed on 33% of the Co atoms in CVD-Co/MoS(2)/Al(2)O(3) after sulfidation and on only half of the Co atoms even after an H(2)-treatment of the sulfided catalyst at 573-673 K. The Co atoms in CVD-Co/MoS(2)/Al(2)O(3) exclusively exhibited an antiferromagnetic property, indicating that even-numbered Co atoms are interacting with each other in the Co-Mo-S phase. A Co-Mo/Al(2)O(3) catalyst, prepared by a conventional impregnation technique, was composed of the antiferromagnetic Co sulfide species as observed in CVD-Co/MoS(2)/Al(2)O(3) in addition to Co(9)S(8). On the basis of the NO adsorption behavior and magnetic property, it is empirically proposed that the structure of the Co-Mo-S phase is represented as a Co sulfide dinuclear cluster located on the edge of MoS(2) particles. The magnetic property of Co/Al(2)O(3) sulfide catalysts depended on the preparation method.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:status |
PubMed-not-MEDLINE
|
| pubmed:month |
Jan
|
| pubmed:issn |
1520-6106
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:day |
13
|
| pubmed:volume |
109
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
288-96
|
| pubmed:year |
2005
|
| pubmed:articleTitle |
Structure of the active sites of Co-Mo Hydrodesulfurization catalysts as studied by magnetic susceptibility measurement and NO adsorption.
|
| pubmed:affiliation |
Department of Material Science, Shimane University, Matsue 690-8504, Japan. yokamoto@riko.shimane-u.ac.jp
|
| pubmed:publicationType |
Journal Article
|