Multiscale simulation of separation process for low-concentration crotonaldehyde in vinyl acetate production

Abstract

In this paper, we focus on the separation of acetic acid and low-concentration crotonaldehyde in the production of vinyl acetate (VAc) from acetylene. Based on the established specific force field for acetic acid, the vapor–liquid equilibrium (VLE) data of the two substances were calculated using Gibbs ensemble Monte Carlo (GEMC) simulations, with the force field parameters for crotonaldehyde obtained through quantum chemistry. By fitting the VLE data, binary interaction parameters were acquired, and the accuracy of the force field parameters and the fitted thermodynamic model was verified. The fitted VLE data and binary interaction parameters were then applied to process simulation, enabling the construction of an azeotropic distillation column model for acetic acid–crotonaldehyde. The design parameters and operating conditions of the azeotropic distillation column were determined, facilitating the recovery of acetic acid and the separation of low-concentration crotonaldehyde. This study aims to provide VLE data for the separation of low-concentration crotonaldehyde and to achieve the separation of acetic acid–crotonaldehyde through process simulation, thereby promoting the industrialization process of the synthesis and separation sections in the production of vinyl acetate from acetylene.