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An azeotropic distillation method is provided for distilling a mixture containing water, acetic acid, and methyl acetate using an azeotrope that is azeotropic with water. An azeotropic distillation method used to distill and separate water, acetic acid, and methyl acetate into individual components, comprising the following steps (1) to (5): (1) A step of distilling the mixture containing water, acetic acid, and methyl acetate to be distilled at a tower top pressure higher than atmospheric pressure in the presence of an azeotrope, thereby separating the mixture into a bottom product fraction containing acetic acid and a top vapor stream containing water, methyl acetate, and the azeotrope ； (2) The step of condensing the overhead distillate vapor obtained in step (1) ； (3) A step of evaporating methyl acetate from the condensate obtained in step (2) by reducing pressure, thereby recovering methyl acetate ； (4) The step of separating the residual liquid obtained in step (3) into an aqueous phase and an oily phase via liquid-liquid separation ； And (5) the step of providing the oil phase obtained in step (4) as an azeotrope to step (1). Abstract: An azeotropic distillation method that involves using an azeotic agent in an azeotropic distillation column to distill the solution to be distilled. The azeotic component containing the azeotic agent is recovered as the overhead distillate, while the solution with reduced content of this azeotic component is recovered as the bottom product ； The method is characterized in that it further includes presetting a target value for the amount of azeotrope retention so as to keep the azeotrope zone within the distillation column within a predetermined range, determining the actual amount of azeotrope retention, and controlling the operating conditions of the distillation column to make the actual amount consistent with said target value. Main claim 1: An azeotropic distillation method in which an azeotrope is used in an azeotropic distillation column to distill a solution to be distilled, the azeotic component containing said azeotrope being recovered in the form of a distillate, and a liquid with reduced content of the azeotic component being recovered as the bottom product of the column; characterized in that a target value for the residence time of the azeotrope is predetermined in order to create an azeotropic zone within a specified range of the azeotropic distillation column, the actual residence time of the azeotrope in the column is determined, and the operating conditions of the distillation column are controlled so that this actual residence time reaches the said target value. Inventor: W.D. Paten. Address: Delaware, United States. Overview: A stripping tower is used to treat the stream obtained from the azeotropic distillation tower and containing an azeotrope, hydrocarbons, and aliphatic acids (such as n-propyl acetate, xylene, and acetic acid respectively) in order to separate the azeotrope from the hydrocarbons, so that the azeotrope can be recycled back to the azeotropic distillation tower. Key point 1: An azeotropic distillation of a feed stream containing fatty carboxylic acids, hydrocarbons, and water is carried out to produce a distillate stream containing fewer amounts of these components and water, which is discharged from the azeotropic zone in the distillation column. The azeotrope is recovered and recycled to the azeotropic zone of the column, while the recovery is performed in a stripping column that generates a bottom product consisting mainly of hydrocarbons and a column product consisting mainly of the azeotrope.