| 摘要 |
A method for preparing an aromatic carbonate is provided to avoid a need for a step for separating a heterogeneous catalyst, to increase the concentration of low-boiling point reactants, and to enable continuous removal of byproducts, thereby realizing excellent productivity and cost-efficiency. A method for preparing an aromatic carbonate by using a dialkyl carbonate or alkylaryl carbonate and aromatic hydroxyl compound as reactants comprises the steps of: (i) injecting the reactants to the top of a heterogeneous catalyst layer(1b) fixed to a reactor(1); (ii) passing a mixture containing the resultant product obtained after a part of the reactants undergoes a reaction in the catalyst and the remaining reactants through the catalyst layer; (iii) carrying out heat exchange between a part of the liquid reactants in the mixture and vaporous reactants in a column(1c) installed at the bottom of the catalyst layer and transferring the heat exchanged mixture back to the catalyst layer, and sending the remaining mixture to a heat exchanger(3) linked to the bottom of the reactor; (iv) heating the mixture transferred to the heat exchanger, introducing the vaporous reactants into the bottom of the column, discharging a part of the liquid mixture to the exterior of the reactor by controlling the level, and introducing the remaining liquid mixture to the top of the catalyst layer; (v) discharging the vaporous byproducts generated from the top of the catalyst layer and vaporous reactants forming an azeotropic mixture with the byproducts to the exterior of the reactor through a distillation tower(5) linked to the top of the reactor, followed by cooling; and (vi) partially refluxing the cooled liquid byproducts and the reactants to the top of the catalyst layer.
|
