Catalytic cracking studies and characterization of steamed Y and LZ-210 zeolites

Journal Article · Tue Nov 01 04:00:00 EST 1988 · Journal of Catalysis; (USA)

DOI:https://doi.org/10.1016/0021-9517(88)90010-3· OSTI ID:7128651

Pellet, R J; Blackwell, C S; Rabo, J A ^[1]

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1. Union Carbide Corporation, Tarrytown, NY (USA)

Catalytic cracking catalysts prepared using Y zeolite crystals which have been silicon enriched by treatment with ammonium fluorosilicate solution show substantially superior crystal retention upon exposure to severe hydrothermal treatments, relative to similarly treated Y-zeolite-based catalysts. The silicon-enriched Y-based catalysts, following hydrothermal pretreatment, also show superior activity retention and higher gasoline selectivity relative to Y-zeolite-based catalysts. The study of steamed Y and the silicon-enriched Y product by solid-state MAS NMR shows that upon steaming the silicon-enriched zeolite displays superior retention of the framework structure relative to Y, and that the Y product shows not only aluminum loss but also significant silicon loss from the crystal framework, contributing to deterioration of the crystal framework, contributing to deterioration of the crystal. Thermometric titrations of Y zeolites, following exposure to steam treatments of increasing severity, indicates that upon severe steam treatment the strong acid character typical of stabilized Y is greatly reduced while a substantial concentration of milder acid sites is formed, similar in acid strength to amorphous silica-alumina gel. These data are interpreted on the basis that upon steaming amorphous alumina and silica-alumina phases are formed, occluded in the zeolite crystal, and that the occluded amorphous, acidic debris adversely affects cracking selectivity to produce gasoline.

• OSTI ID: 7128651
• Journal Information: Journal of Catalysis; (USA), Journal Name: Journal of Catalysis; (USA) Vol. 114:1; ISSN 0021-9517; ISSN JCTLA
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020400* -- Petroleum-- Processing
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
AMORPHOUS STATE
ANTIKNOCK RATINGS
CATALYTIC CRACKING
CATALYTIC EFFECTS
CHALCOGENIDES
CHEMICAL REACTIONS
CRACKING
CRYSTAL STRUCTURE
DECOMPOSITION
ELEMENTS
ENERGY SOURCES
ENRICHMENT
FOSSIL FUELS
FUELS
GASOLINE
HEAT TREATMENTS
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
LIQUID FUELS
MAGNETIC RESONANCE
MATERIALS
MINERALS
NUCLEAR MAGNETIC RESONANCE
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PETROLEUM
PETROLEUM PRODUCTS
PYROLYSIS
RESONANCE
SAMPLE PREPARATION
SEMIMETALS
SILICA
SILICON
SILICON COMPOUNDS
SILICON OXIDES
STEAM
THERMOCHEMICAL PROCESSES
ZEOLITES