Kinetics and selectivity of reactions of 1‐alkenes on HY zeolite: The influence of chain length

Abstract

Catalytic reactions of 1‐alkenes on HY have been studied at 400°C. Skeletal isomerization to the corresponding rnonornethylalkene is the dominant initial process. Cracking and coke formation are also observed as initial processes. Initial cracking selectivity can be accounted for by monomolecular β‐scission processes involving a carbenium ion intermediate. However, the initial cracking product distribution for l‐hexene must be explained by assuming some contribution from a dimerization‐cracking mechanism. The kinetics of these processes have been fitted by a model previously used to describe the reactions of n‐alkanes. It is found that the rate constants for both skeletal isomerization and cracking increase with chain length of the feed alkene.

Catalytic Cycles and Selectivity of Hydrocarbon Cracking on Y-Zeolite-Based Catalysts

“…14 belong to family 5; steps 7 and 10 belong to family 6; step 12 belongs to family 7; and steps 5 and 8 belong to family 9. Our experimental data (Yaluris et al, 1994a) and results presented by other workers (Abbot and Wojciechowski, 1988b;Corma et al, 1985;Kramer et al, 1985;McVicker et al, 1983;Ono and Kanae, 1991;Shertukde et al, 1992;Shigeishi et al, 1991) indicate that isomerization and desorption processes are equilibrated at the reaction conditions employed here. Therefore, we set the Evans-Polanyi constants of families 4 and 5 to zero.…”

Quantum chemistry of the Fischer–Tropsch reaction catalysed by a stepped ruthenium surface

“…12,13 Experimentally, it is usually found that the C 1 and C 2 product selectivities deviate from the ASF distribution. 12,[14][15][16][17][18][19][20] Two important schools of thought exist about the nature of the catalytically active surface. On the one hand, it is assumed that the close-packed surfaces (terraces) are the active sites.…”

Kinetic modeling of C2–C7 olefins interconversion over ZSM-5 catalyst

“…The detailed route depends on the catalyst 41 acidity and molecular size of the carbenium ion [9,[13][14][15][16]. Most of 42 the research interests involving olefins interconversion kinetics 43 focus on two separate fields: one is the transformation of light 44 olefins (C 2 -C 4 ) [17][18][19] for the Methanol-to-Olefins (MTO) process, 45 where C 2 -C 3 are the dominant products [20][21][22][23][24]; the other is the 46 conversion of higher olefins [25,26] for the Fluidized Catalytic 47 Cracking (FCC) process, where C 5 -C 8 olefins are produced and 48 undergo further cracking. Neither covers full C 2 -C 7 range of the 49 MTP process.…”