Abstract
The competitive hydroconversion of heptane and nonane molecules in their mixture was studied in a continuous flow, fixed-bed reactor filled with Pt/HY zeolite catalyst. Liquid-phase reaction conditions were established at reaction temperatures of 230, 250, and 270°C by pressurizing the reactor at 100 bar. Hydrogen was supplied in an absorbed state with the liquid hydrocarbon feed. Under these liquid-phase reaction conditions, the apparent reaction rates of heptane and nonane were almost identical. In a similar experiment under vapor-phase conditions, nonane was much more reactive than heptane. The conversion data under liquid-phase conditions were analyzed with an adsorption-reaction model based on intrinsic kinetic parameters obtained from vapor-phase experiments. The model revealed that the enhanced reactivity of heptane in the liquid phase was due to its preferential adsorption. Simulation of the adsorption of the heptane/nonane mixture in the pores of zeolite Y with the configurational-bias Monte Carlo method confirmed the preferential adsorption of heptane in zeolite Y at high pressure. Under such conditions, in zeolite Y supercages the packing of the smaller heptane molecules is more favorable than that of the larger nonane molecules.
Original language | English |
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Pages (from-to) | 66-73 |
Number of pages | 8 |
Journal | Journal of Catalysis |
Volume | 220 |
Issue number | 1 |
DOIs | |
Publication status | Published - 15 Nov 2003 |
Externally published | Yes |
Funding
This research was financially supported by FWO Vlaanderen (G.0127.99). J. Denayer is grateful to the F.W.O.-Vlaanderen, for a fellowship as postdoctoral researcher. W.H. acknowledges the Flemish I.W.T. for a PhD fellowship. S.C., R.K., and B.S. thank the Netherlands Research Council for Chemical Sciences (CW) for partial support and the European Commission for a Marie Curie Individual Research Fellowship (to S.C.). The CHIS and COK teams participate in the IAP-PAI programme on Supramolecular Chemistry and Catalysis, sponsored by the Belgian government. The team from K.U. Leuven acknowledges the Flemish Government for a G.O.A. grant.
Keywords
- Alkane mixtures
- CBMC simulation
- High pressure
- Hydrocracking
- Liquid phase
- Molecular competition
- Pt/HY zeolite