Synergism of Pt/[gamma]-Al[sub 2]O[sub 3] and Pt/[beta] zeolite in the reforming of naphthenes

Journal Article · Tue Mar 01 04:00:00 EST 1994 · Industrial and Engineering Chemistry Research; (United States)

DOI:https://doi.org/10.1021/ie00027a004· OSTI ID:7074632

Smirniotis, P G; Ruckenstein, E ^[1]

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1. State Univ. of New York, Buffalo, NY (United States). Dept. of Chemical Engineering

Composite catalysts of Pt supported on both zeolite [beta] and [gamma]-Al[sub 2]O[sub 3] are employed for the reforming of methylcyclopentane and methylcyclohexane. Due to its relatively high Pt dispersion, Pt/[gamma]-Al[sub 2]O[sub 3] is responsible for dehydrogenation reactions leading to methylcycloolefins. Pt/[beta] zeolite, which has a much higher Bronsted acidity than [gamma]-Al[sub 2]O[sub 3],is responsible for the bimolecular alkylation reactions leading to aromatics, the transalkylation reactions of aromatics, and the isomerization reactions of methylcycloolefins to C[sub 6] cycloolefins which further via dehydrogenation lead to benzene. The residence time plays an important role because the dehydroisomerization reactions are much slower than the bimolecular alkylation reactions. At a high residence time and with methylcyclopentane as feed, the composites generate a synergistic effect which leads to a maximum in the benzene yield at about 40 wt % Pt/[beta] zeolite. With methylcyclohexane as feed, high aromatic (mainly toluene) yields are obtained for zeolite contents below 30 wt %. Bimolecular alkylation reactions, which are stimulated by the zeolite pore structure and the high Bronsted acidity of zeolite [beta], also occur and lead to aromatics with a larger number of carbon atoms than the feed naphthene and to a better utilization Of C[sub <6] olefins and paraffins generated by cracking. Beneficial effects can be achieved by balancing the acidic with the dehydrogenation functions of a reforming catalyst through the incorporation of Pt/[beta] zeolite into Pt/[gamma]-Al[sub 2]O[sub 3].

• OSTI ID: 7074632
• Journal Information: Industrial and Engineering Chemistry Research; (United States), Journal Name: Industrial and Engineering Chemistry Research; (United States) Vol. 33:3; ISSN IECRED; ISSN 0888-5885
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020400* -- Petroleum-- Processing
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CATALYTIC EFFECTS
CATALYTIC REFORMING
CHALCOGENIDES
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
ELEMENTS
HYDROAROMATICS
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
MATERIALS
METALS
MINERALS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PLATINUM
PLATINUM METALS
REFORMER PROCESSES
SILICATE MINERALS
TRANSITION ELEMENTS
YIELDS
ZEOLITES