Electron spin resonance studies of ethylene dimerization catalyzed by nickel species on Y zeolites

• Published in: Journal of physical chemistry (1952) Vol. 94; no. 7; pp. 3117 - 3121
• Main Authors: Ghosh, Ashim K, Kevan, Larry
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 05.04.1990
• Subjects: ALKENES; CATALYSTS; CHEMICAL REACTIONS; Chemistry; DATA; DATA ANALYSIS; DIMERIZATION; ELECTRON SPIN RESONANCE; ETHYLENE; Exact sciences and technology; EXPERIMENTAL DATA; General and physical chemistry; HYDROCARBONS; INFORMATION; INORGANIC ION EXCHANGERS; INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ION EXCHANGE MATERIALS; Ion-exchange; MAGNETIC RESONANCE; MATERIALS; MEASURING INSTRUMENTS; MEASURING METHODS; MINERALS; NUMERICAL DATA; ORGANIC COMPOUNDS; POLYMERIZATION; RESONANCE 400201 > Chemical & Physicochemical Properties; Surface physical chemistry; ZEOLITES; Catalytic reaction; Hydrocarbon; Ethylene; EPR spectrometry; Nickel Ions; Zeolite; Calcium Ions; Experimental study; Supported catalyst; Molecular sieve; Ion exchange; Catalyst activity; Dimerization; Modified material
• ISSN: 0022-3654; 1541-5740
• DOI: 10.1021/j100370a068

Electron spin resonance studies of CaNi-Y zeolites reduced thermally in H{sub 2} indicate the formation of species A and C assigned to Ni{sup +} ions in the {beta}-cage and the {alpha}-cage, respectively, complexed with H{sub 2}. Species C disappears completely and species A partially after evacuation of the sample at 100{degree}C for 10 min. Simultaneously, a new species, assigned to isolated Ni{sup +} ions in the {alpha}-cage, is seen and gives species E rapidly due to coordination with ethylene on exposure of the sample to ethylene or butenes, suggesting that the Ni{sup +} species migrate into the {alpha}-cage where the olefin molecules coordinate with them by replacing H{sub 2}.