PROCESS FOR THE PRODUCTION OF CARBOXYLIC ACID ESTERS EMPLOYING SUPERATMOSPHERIC PRESSURE

摘要

Conventionally volatile esters such as ethyl acetate are produced by continuously feeding an alcohol and an acid to an esterification reaction still containing an esterification catalyst, removing the ester and water so produced overhead by distillation and returning a proportion of the ester product as reflux to the distillation section in order to maintain the reaction mixture essentially anhydrous. In the process of the invention, instead of operating the esterification still at atmospheric pressure as in prior art processes, superatmospheric pressure, typically in the range 1.38 to 13.8 bar absolute, is employed. This results in higher ester production rates. Although the process is applicable to the production of esters from either ethanol, n-propanol or iso-propanol and acetic, propionic and butyric acids, ethanol and acetic acid comprise the preferred feedstock Typically the reaction temperature is in the range 110 to 160 DEG C. Esterification catalysts include sulphuric acid and toluene-para-sulphonic acid.