Designing an extractive distillation process for separating a heterogeneous mixture of isopropyl alcohol, isopropyl acetate, and water

• A novel approach for separating complex ternary azeotropic mixtures was developed. • Two processes, D-CED and D-SSED, were designed using green solvent glycerol. • Advanced optimization was performed using a genetic algorithm. • D-SSED achieved significant cost and CO2 reductions over the conventional method. • An innovative heat exchanger design effectively minimized energy consumption. This study investigates the separation of the challenging ternary mixture of isopropyl acetate (IPAC), isopropyl alcohol (IPA), and water, which forms four azeotropes. Two extractive distillation processes are proposed and designed: conventional extractive distillation with double entrainer (D-CED) and side-stream extractive distillation with double entrainer (D-SSED), using glycerol as an eco-friendly solvent to enhance the relative volatility among the components. The innovation of this work is the systematic application and comparison of double-entrainer CED and an advanced side-stream configuration for this specific four-azeotrope system using glycerol as a green solvent. The processes were thermodynamically modeled using the NRTL model, simulated in Aspen Plus, and optimized using a genetic algorithm to reduce the total annual cost (TAC) and CO 2 emissions. Important parameters such as the number of trays, feed tray position, reflux ratio, and entrainer flow rate were optimized. A novel double-entrainer D-SSED configuration is proposed for this azeotropic system, which demonstrated superior economic and environmental performance, resulting in a 3.5% reduction in TAC and a 4.2% reduction in CO 2 emissions compared to the D-CED process. In addition, heat integration and solvent temperature effects are systematically investigated, and a heat exchanger is integrated to reduce energy consumption by minimizing reboiler and cooler duties. This study highlights the effectiveness of the proposed D-SSED configuration as a sustainable and cost-efficient approach for separating complex azeotropic mixtures.