Abstract
| Original language | Undefined |
|---|---|
| Pages (from-to) | 434-442 |
| Number of pages | 9 |
| Journal | Journal of catalysis |
| Volume | 203 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - 2001 |
Keywords
- Sulfur tolerance
- IR-74567
- Benzene hydrogenation
- METIS-204815
Cite this
}
Sulfur-tolerant Pt-supported catalysts for benzene hydrogenation. II. Influence of cation exchange level for Pt/MOR-based catalysts. / Simon, L.; van Ommen, J.G.; Jentys, A.; Lercher, J.A.
In: Journal of catalysis, Vol. 203, No. 2, 2001, p. 434-442.Research output: Contribution to journal › Article › Academic › peer-review
TY - JOUR
T1 - Sulfur-tolerant Pt-supported catalysts for benzene hydrogenation. II. Influence of cation exchange level for Pt/MOR-based catalysts
AU - Simon, L.
AU - van Ommen, J.G.
AU - Jentys, A.
AU - Lercher, J.A.
PY - 2001
Y1 - 2001
N2 - Two reaction pathways are described for the hydrogenation of benzene over Pt/MOR, i.e., (i) on the metal particles and (ii) on Brønsted acid sites of MOR at the boundary to the metal, with atomic hydrogen being dissociated on the metal. The ratio between the two pathways depends on the zeolite acid site concentration and on the available metal surface sites. The deactivation of fully H+ ion exchanged zeolites and the markedly slower intrinsic rate on Na+ ion exchanged samples led to a pronounced maximum in the steady-state activity for benzene hydrogenation with partly H+ exchanged samples. At high pressure and in the presence of thiophene, the benzene hydrogenation activity of Pt/MOR was higher via the pathway involving Brønsted acid sites than via the pathway involving only Pt. Therefore, in the presence of thiophene the type of alkali cation exchanged did not significantly influence activity, whereas Brønsted acid site concentration did. The relative sulfur tolerance of Pt/MOR during benzene hydrogenation was shown to depend on (i) the acid site concentration, which increases both the benzene conversion and the rate of C–C bond breaking leading to coke formation, and (ii) the partial pressure of hydrogen, which increases the concentration of hydrogen atoms available for hydrogenating benzene molecules activated via both pathways.
AB - Two reaction pathways are described for the hydrogenation of benzene over Pt/MOR, i.e., (i) on the metal particles and (ii) on Brønsted acid sites of MOR at the boundary to the metal, with atomic hydrogen being dissociated on the metal. The ratio between the two pathways depends on the zeolite acid site concentration and on the available metal surface sites. The deactivation of fully H+ ion exchanged zeolites and the markedly slower intrinsic rate on Na+ ion exchanged samples led to a pronounced maximum in the steady-state activity for benzene hydrogenation with partly H+ exchanged samples. At high pressure and in the presence of thiophene, the benzene hydrogenation activity of Pt/MOR was higher via the pathway involving Brønsted acid sites than via the pathway involving only Pt. Therefore, in the presence of thiophene the type of alkali cation exchanged did not significantly influence activity, whereas Brønsted acid site concentration did. The relative sulfur tolerance of Pt/MOR during benzene hydrogenation was shown to depend on (i) the acid site concentration, which increases both the benzene conversion and the rate of C–C bond breaking leading to coke formation, and (ii) the partial pressure of hydrogen, which increases the concentration of hydrogen atoms available for hydrogenating benzene molecules activated via both pathways.
KW - Sulfur tolerance
KW - IR-74567
KW - Benzene hydrogenation
KW - METIS-204815
U2 - 10.1006/jcat.2001.3339
DO - 10.1006/jcat.2001.3339
M3 - Article
VL - 203
SP - 434
EP - 442
JO - Journal of catalysis
JF - Journal of catalysis
SN - 0021-9517
IS - 2
ER -