Reaction Mechanism of Carbon-Carbon Bond Formation on Zeolite Catalyst

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IR studies were carried out to elucidate the reaction mechanism of the carbon-carbon bond formation that is one of the most important reactions of zeolite catalysis. Reactivity and adsorption structure of olefins on zeolites were also investigated.(1) Reactivity of methoxy species formed by the reaction of methanol on Zeolites :Three sorts of methoxy species were formed on zeolite by the reaction of methanol in the temperature range between 140 and 240℃. It was observed that dimethyl ether was formed by the reaction of these methoxy species and methanol,(2) Acid properties of hydroxyl groups on zeolites :Behavior of acidic OH groups on zeolites at higher temperature was examined by IR spectroscopy in situ. Adsorption structure of water on ferrierite that has small cages was also examined.(3) Adsorption of olefins on zeolites :It was observed that olefins were selectively adsorbed on active sites on ferrierite that has small cages. The change of the adsorption structure with the change of the adsorption temperature was also studied.(4) Double bond migration of olefins on zeolites :It was found that double bond of olefins migrated without forming protonated species in the low temperature range.(5) The structure and reactivity of the alkoxy species formed by the adsorption of olefins on zeolites :Dimerized alkoxy species were observed for the adsorption of isobutene on zeolites above 200 K.(6) H/D exchange reaction of olefins on zeolites :The H/D exchange reaction between olefins and hydroxy groups on zeolites was studied.