A novel ethyl acetate synthesis process with low energy consumption: Simulation optimization and experimental verification

In response to the problem of high energy consumption in the synthesis of ethyl acetate using excess ethanol, we propose novel low-energy technology for synthesizing ethyl acetate using a considerable excess of acetic acid which saves 80 % energy. Extreme excess of acetic acid ensures the complete conversion of ethanol. The main component at the top of reaction distillation column is only the azeotrope of ethyl acetate and water, which can be easily separated via direct stratification. This process was systematically investigated by combining experiments and simulations. The process simulation is conducted based on the kinetic equation obtained by experiments. The effects of excess acetic acid, liquid holdup in the reboiler, number of theoretical plates, and reflux ratio on product distribution and energy consumption of the reaction distillation column were studied. Furthermore, the main process parameters of the ester purification column and the water-treatment column were optimized. The simulation results were well validated by pilot-scale experiments. Using three distillation columns and under the optimized conditions, the proposed process with a 15-fold excess of acetic acid, and using molecular sieve membrane for water removal from ester, an ethyl acetate purity of 99.999 wt% was achieved with a total energy consumption of 1120 kJ/kg.