| 摘要 |
PURPOSE:To obtain a dialkylnaphthalene useful as a raw material for naphthalenedicarboxylic acid, etc., suitable for production of polyester or polyamide in a prolonged life of catalyst by a method of readily separating by-products. CONSTITUTION:In producing a dialkylnaphthalene by reacting naphthalene or a 2-alkylnaphthalene with an alkylating agent in the presence of a porous solid acid catalyst, the reaction is effected in the presence of an aromatic solvent containing an aromatic ring in the skeleton such as toluene, xylene or mesitylene in a subcritical or a supercritical state prescribed by O.9Tc<T<2Tc (T is temperature; Tc critical temperature) and 0.9Pc<P<50Pc (P is pressure; Pc is critical pressure) based on the critical constant of the solvent to extremely prolong the life of the catalyst by a simple method. After the reaction is over, when the pressure of a high-pressure fluid is reduced, the pressure is dropped at multiple stage to readily separate the objective compound. |
