Catalytic reactions of n-dodecane on aluminosilicates

Journal Article · Wed Feb 01 00:00:00 EST 1989 · Journal of Catalysis; (USA)

DOI:https://doi.org/10.1016/0021-9517(89)90054-7· OSTI ID:6843779

Abbot, J; Wojciechowski, B W ^[1]

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1. Queens's Univ., Kingston, Ontario (Canada)

Catalytic reactions of n-dodecane at 400 C have been studied on HY, LaY, amorphous silica-alumina, HZSM-5, and H-mordenite. The molar distributions of initial products are almost identical on HY and LaY, while the distributions are shifted toward lower molecular weight products on the other catalysts. This the authors associate with initiation of cracking at Bronsted sites, which have higher acidities on amorphous silica-alumina, H-mordenite, and HZSM-5 than those present on HY and LaY. With the exception of HZSM-5, initial ratios of branched/linear paraffins are similar on all catalysts and show a preference for the branched isomer in the range C{sub 4}-C{sub 8}. On HZSM-5 the linear isomer is formed preferentially. This is attributed to restriction in the rearrangement of the carbonium ion in the narrower pores of the pentasil. The kinetic model previously applied to the cracking of linear paraffins on HY can also be applied to the cracking of n-dodecane on other aluminosilicate catalysts. The consequent kinetic parameters show that inhibition of the cracking reaction is greater on HY and LaY than on amorphous silica-alumina, H-mordenite, and HZSM-5. This is attributed to the stronger Lewis acidity of the carbenium ions formed by adsorption of product olefins at the stronger Bronsted sites on the later group of catalysts.

• OSTI ID: 6843779
• Journal Information: Journal of Catalysis; (USA), Vol. 115:2; ISSN 0021-9517
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
DODECANE
CATALYTIC CRACKING
MORDENITE
CATALYTIC EFFECTS
ZEOLITES
ALKANES
ALUMINIUM OXIDES
AMORPHOUS STATE
CHEMICAL REACTION KINETICS
COMPARATIVE EVALUATIONS
ISOMERIZATION
MATHEMATICAL MODELS
MOLECULAR STRUCTURE
SILICON OXIDES
SURFACE PROPERTIES
TEMPERATURE DEPENDENCE
ALUMINIUM COMPOUNDS
CHALCOGENIDES
CHEMICAL REACTIONS
CRACKING
DECOMPOSITION
HYDROCARBONS
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
KINETICS
MATERIALS
MINERALS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PYROLYSIS
REACTION KINETICS
SILICATE MINERALS
SILICON COMPOUNDS
THERMOCHEMICAL PROCESSES
020400* - Petroleum- Processing