Ethyl Acetate Production from Ethanol and Acetic Acid

The process under analysis comprises two major sections: (1) Reaction and (2) Purification.

Reaction. In the process under analysis, the reaction is conducted in two steps. Firstly, the reactants, acetic acid and ethanol, in slight excess, are mixed together in pre-esterification reactors along with sulfuric acid, that is used as a catalyst for the esterification. This first reaction is conducted until equilibrium is reached and then the reactors output is directed to an esterification column. There, two methods are used to shift the reaction equilibrium towards the production of ethyl acetate: water by-product removing and excess ethanol addition. Excess ethanol is added to reaction medium via an upstream recycle stream that is fed to the bottom of the column. Water is continuously removed from the reaction medium through column bottoms while the reactants, and ethyl acetate move upward in the column.

Purification. The top product from the esterification column still containing a large excess of ethanol is directed to a further distillation step. The top product of this column is a ternary azeotrope of Ethyl Acetate, ethanol and water. To further purify Ethyl Acetate in the ternary azeotrope mixture it is first required to break down the azeotrope. The ternary azeotrope mixture is mixed with water and then settled in a decanter in order to break down the azeotrope. The organic phase recovered from the decanter, more concentrated in Ethyl Acetate, can now be directed to a final distillation step to reach product specification.