Heating and adding catalyst can only accelerate the reaction speed, and has no effect on the composition of the balanced material. In order to increase the yield of esters, excessive carboxylic acids and alcohols are often added, or the resulting water is constantly removed from the reaction mixture. If the boiling point of the ester produced is very low, the ester can also be steamed out. In short, the equilibrium is destroyed to improve the yield of ester. For example, the industrial production of ethyl acetate is to use excessive acetic acid, the generated ethyl acetate and water azeotrope (water 8.6%, ethyl acetate 91.4%, constant boiling point 70.45℃) to steam out, so that the balance is destroyed, and then continue to add acetic acid and ethanol, continue to steam ethyl acetate and water, continuous production.