摘要 |
The present invention relates to a process for producing glycol esters by reacting lower aliphatic carboxylic acid and olefin in the presence of a catalyst containing (A) a palladium component, (B) a metal component selected from the metals of Periodic Table Groups IA, IB, IIA, IIB, VA, VIIB and VIII, (C) a halogen component and (D) a nitrogen-containing oxide, and oxygen. The first process is characterized in that a halogen ion source and/or a nitric acid ion source is added in the course of the reaction. Further, the second process is characterized by including: (1) a step in which after the reaction, hydrogen is introduced to reduce the palladium catalyst; (2) a step in which the reduced solution obtained is separated into reduced palladium and the reaction solution by filtration; (3) a step in which the reaction solution is distilled to separate the lower aliphatic carboxylic acid and the glycol esters; and (4) a step in which to the reduced palladium obtained in the step (2) above, a lower aliphatic carboxylic acid, the distillation residue obtained in the step (3), a halogen ion source and/or a nitric acid ion source are added to prepare a catalyst solution, and the catalyst solution is introduced in the reaction system. According to the present invention, the selectivity is increased and also the separation of the product from the reaction solvent is facilitated. Further, the process can be carried out continuously, and the catalyst can be used repeatedly. |