To industrially advantageously produce dimethyltetralin useful as a raw material for naphthalenedicarboxylic acid by the cyclization of tolylpentaene in the presence of a catalyst supporting sulfate ions.
This method is to perform the cyclization of 5-tolyl-penta-2-ene in the presence of a catalyst supporting sulfate ions (preferably derived from sulfuric acid and/or ammonium sulfate, or the like). A carrier for the catalyst is preferably zirconium oxide, titanium oxide, aluminum oxide, silica or a mixture of at least two of them. The cyclization temperature is preferably 50-400°C, more preferably 70-300°C. A fixed bed system, moving bed one and fluidized bed one, or the like, can all be employed as a reaction system and a fixed bed flow-through system is preferable in the case of continuous operation. The charge rate of a raw material per the unit volume of the catalyst is 0.01-5 h.-1 (preferably 0.1-1 h.-1) in terms of LHSV.
FUSHIMI NORIO
TAKAGAWA MINORU
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