Kinetics of reactions of C/sub 8/ olefins on HY zeolite
Reactions of two C/sub 8/ olefins (n-octene and 2,4,4-trimethylpentene) have been studied on HY at 300/sup 0/C. Skeletal isomerization is the dominant reaction of n-octene (initial selectivity 0.98), while cracking is the dominant reaction of 2,4,4-trimethylpentene (initial selectivity 0.80). Conversion rates of both olefins can be fitted by a kinetic expression previously applied to the cracking of n-paraffins on HY at 400/sup 0/C. The kinetic rate constants for reaction of these olefins, independent of adsorption parameters, have been calculated, and show that the sum of the rate constants for cracking 2,4,4-trimethylpentene is approx. 160 times greater than that for skeletal isomerization of n-octene. The parameters obtained show that adsorption of olefins on HY decreases with an increased degree of branching. Methylheptenes are less strongly adsorbed than linear octenes. Trimethylpentenes are less strongly adsorbed than isobutene. This trend is also observed by comparing initial coke formation on HY from the two olefin feedstocks, which shows that n-octenes are adsorbed to a significantly higher extent than 2,4,4-trimethylpentene. The decay parameters show that aging occurs much more rapidly for 2,4,4-trimethylpentene than for n-octene. There appears to be no simple relationship between total coke deposited and catalyst deactivation.
- Research Organization:
- Queen's Univ., Kingston, Ontario (Canada)
- OSTI ID:
- 5204528
- Journal Information:
- J. Catal.; (United States), Journal Name: J. Catal.; (United States) Vol. 108:2; ISSN JCTLA
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
020400* -- Petroleum-- Processing
ADSORPTION
ALKENES
CATALYSTS
CATALYTIC CRACKING
CATALYTIC EFFECTS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COKE
CRACKING
DEACTIVATION
DECOMPOSITION
DEPOSITION
HYDROCARBONS
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
ISOMERIZATION
KINETICS
MATERIALS
MINERALS
OCTENES
ORGANIC COMPOUNDS
PENTENES
PYROLYSIS
REACTION KINETICS
SORPTION
THERMOCHEMICAL PROCESSES
ZEOLITES