EXAFS identification of the active species in supported niobium sulfide hydrotreatment catalysts

被引:22
作者
Allali, N
Prouzet, E
Michalowicz, A
Gaborit, V
Nadiri, A
Danot, M
机构
[1] UNIV NANTES,CNRS,UMR 6501,IMN,LAB CHIM SOLIDES,F-44322 NANTES 3,FRANCE
[2] UNIV PARIS 12,FAC SCI & TECHNOL,LAB PHYS MILIEUX DESORDONNES,F-94000 CRETEIL,FRANCE
[3] UNIV PARIS 11,LURE,CNRS,F-91405 ORSAY,FRANCE
[4] UNIV MOULAY ISMAIL,FAC SCI,LAB CHIM MINERALE APPL,BENI MHAMED,MEKNES,MOROCCO
关键词
niobium sulfides; carbon support; alumina support; EXAFS; hydrotreatment;
D O I
10.1016/S0926-860X(97)00069-0
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
We present a Nb K-edge EXAFS study of carbon-and alumina-supported niobium sulfide hydrotreatment catalysts. NbS2 and NbS3 entities have been evidenced on the carbon support, and NbS2 and Nb1-yS ones on the alumina Support. EXAFS spectra of carbon-supported species, which are highly disordered, were analyzed through an asymmetric distance distribution model. Considering their poor dispersion, Nb1-yS species can be thought to be intrinsically highly active. Their activity, and that of NbS3 entities as well, can possibly be related to cation clustering. Niobium sulfides appear as very sensitive to support effects.
引用
收藏
页码:333 / 354
页数:22
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