Application of reactive distillation for production of n-butyl acetate from n-butanol and dilute acetic acid

Abstract

In this research, the simulations of n-butyl acetate synthesis from n-butanol and dilute acetic acid via reactive distillation, in which chemical reactions and separations occur simultaneously, were studied by ASPEN PLUS program. n-butyl acetate esterification was catalyzed by Amberlyst 15. The objective of this work is to produce n-butyl acetate with a concentration not less than 98 mol%. he studies were divided into 2 main parts of pilot and industrial scales. In the pilot scale study, it was found that the reactive distillation equipped with a decanter with total recycle of the organic phase to the column at stage 2 is a suitable column configuration. For the single reactive distillation column, when the concentration of acetic acid is lowered, higher overall energy of the system is required. Considering the case with a pretreatment of acetic acid from 35 wt% to 65 wt%, the pervaporation-reactive distillation hybrid system requires lower energy than the distillation-reactive distillation hybrid system as well as the case with the single reactive distillation. In the industrial scale study, total energy consumptions of the systems follow similar trend of the pilot scale study. However, when considering the total annual cost for the case with 35 wt% acetic acid feed, it was revealed that the single reactive distillation consisting of 0 rectifying, 7 reaction, and 2 stripping stages offers the lowest total annual cost followed by the pervaporation-reactive distillation hybrid system and the distillation-reactive distillation hybrid system,respectively.