CONTINUOUS PRODUCTION OF THERMALLY UNSTABLE ACID ESTER

PROBLEM TO BE SOLVED: To provide a continuous ester-formation process for a thermally unstable acid by esterifying the acid with an alcohol, if necessary, in the presence of a catalyst. SOLUTION: The esterification reaction is carried out in substantially only one reaction zone at about 80-130 deg.C. The acid and an excessive amount of the alcohol are continuously fed to the reaction zone and the alcohol and the reaction water are continuously taken out in the form of vapor, while the reaction mixture rich in the ester component is removed in the liquid form, and the ester is obtained from the reaction mixture. This esterification process is suitable for production of an ester of 4-chlorobutyric acic with an alcohol of 1-3 carbon atoms.