Abstract: Disclosed is a method and an apparatus for manufacturing at least two esters. The method includes steps of: (a) reacting an acid and an alcohol mixture in a reactive distillation (RD) column to generate an alcohol-ester-water azeotrope, wherein the alcohol mixture includes at least two alcohols; (b) separating the alcohol-ester-water azeotrope as the organic mixture and water in a decanter; (c) purifying the organic mixture to generate the ester mixture in a stripper; and (d) performing the ester-ester separation on the ester mixture to generate at least two esters in a distillation column, wherein the number of at least two esters is the same with that of at least two alcohols. The unpurified ester mixture carrying heat can be refluxed into stripper for saving energy and enhancing the efficiency of purification.

Abstract: A method for preparing an ester is provided. The method includes steps of mixing an acid and an alcohol in a reactive distillation column to generate a first gas mixture; transporting the first gas mixture out of the reactive distillation column; cooling down the first gas mixture for a phase separation to obtain a first liquid mixture in an upper phase; transporting the first liquid mixture back to the reactive distillation column; obtaining a second liquid mixture at a middle section of the reactive distillation column; transporting the second liquid mixture to a separative distillation column; and obtaining the ester at a bottom section of the separative distillation column.

Abstract: The system and method for producing diester are provided. The system includes a first distillation unit reacting a dicarboxylic acid with an alcohol to produce a first gaseous mixture, a first cooling unit connected to the first distillation unit and cooling the first gaseous mixture into a first liquid mixture, a second distillation unit connected to the first cooling unit and separating the first liquid mixture into a second gaseous mixture and a second liquid mixture, and a liquid-liquid extraction unit connected to the second distillation unit and separating the second liquid mixture into an aqueous-rich mixture and an organic-rich mixture from which the diester is obtained.

Abstract: The method and apparatus for improving the esterification procedure, in particular for improving the esterification procedure to obtain an ester of low carbon number such as the ethyl acetate and the isopropyl acetate, are provided. By means of the provided method and apparatus, the conversion ratio of the esterification procedure is significantly increased and hence an ester product of a relatively high purity, up to the industrial specification, is obtained.