Catalytic reactions of branched paraffins on HY zeolite

Journal Article · Sat Oct 01 00:00:00 EDT 1988 · Journal of Catalysis; (USA)

DOI:https://doi.org/10.1016/0021-9517(88)90264-3· OSTI ID:6829424

Abbot, J; Wojciechowski, B W ^[1]

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

Catalytic reactions on HY zeolite have been studied for 2,2,4-trimethylpentane at 300 and 400{degree}C and for 2-methylpentane at 500{degree}C. Initial selectivity values were obtained for all reaction products. Molecular hydrogen was formed as an initial product from reaction of 2-methylpentane, although this was not previously observed for reaction of n-hexane on HY. This shows that hydrogen can be formed as a primary product when the structure of feed molecule contains a hydrogen atom bonded to a tertiary carbon. In this respect reactions of paraffins on solid acid catalysts are analogous to those in liquid superacid media. In general, there are three distinct processes which can lead to evolution of molecular hydrogen during cracking processes: (a) thermal reactions, (b) hydrogen production in association with the formation of coke and aromatics, and (c) dehydrogenation resulting from interaction of a Bronsted proton with a tertiary hydrogen atom in a branched molecule. The tendency to liberate hydrogen increases with temperature for each process. Formation of unsaturated coke deposits from reaction of 2,2,4-trimethylpentane was found to be significantly greater at 300{degree}C than at 400{degree}C. Coke formation was, however, not accompanied by the production of volatile aromatic species, showing that coke and aromatics may be produced by independent pathways.

• OSTI ID: 6829424
• Journal Information: Journal of Catalysis; (USA), Vol. 113:2; ISSN 0021-9517
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
08 HYDROGEN
ALKANES
CATALYTIC CRACKING
ZEOLITES
CATALYTIC EFFECTS
AROMATICS
CHEMICAL REACTION KINETICS
COKE
DEHYDROGENATION
HEXANE
HYDROGEN PRODUCTION
SYNTHESIS
TEMPERATURE DEPENDENCE
CHEMICAL REACTIONS
CRACKING
DECOMPOSITION
HYDROCARBONS
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
KINETICS
MATERIALS
MINERALS
ORGANIC COMPOUNDS
PYROLYSIS
REACTION KINETICS
THERMOCHEMICAL PROCESSES
020400* - Petroleum- Processing
080100 - Hydrogen- Production