Process Design And Optimization For Separating Diisopropyl Ether-Isopropanol-Water Azeotropes Of Extractive Distillation Coupled With Pervaporation

Extractive distillation（ED）technology is a special distillation clean production technology widely used in the separation of azeotropes in the chemical and pharmaceutical industries.This study proposes a rigorous process TAC model index（PECI）and LCA impact model index（LTEDI）for predicting and screening excellent green performance entrainers based on the system engineering thinking of chemical processes.The relative volatility of heavy components and entrainer is determined by the quantitative and qualitative prediction of the trend relationship betweenα_HC/SOL,the tray number NT of solvent recovery column and the green sustainability（AP,GWP）and ecotoxicity（FETP,HTP,TETP）characteristics of LTEDI model indexes,TAC,Q_R,PECI,LTEDI in the process.Screening the excellent green performance entrainer with economic,environmentally friendliness and green sustainability in the ED separation process.The novel process TAC model extends from a simple model of two-dimensional intersecting factors to a strict model of three-dimensional parallel factors in the ED separation process.It is suitable for different process optimization algorithms and has wide predictability and applicability.It not only saves a lot of computational workloads in the traditional comparative chemical process design,simulation and optimization,but also determines the optimal performance of green extraction entrainers quickly,accurately and efficiently based on the minimum model index.Based on the strict process economic model index（PECI）and LCA impact model index（LTEDI）prediction,ethylene glycol（EG）is selected as the optimal green performance entrainer for the separation of DIPE/IPA/H₂O ternary azeotropes by ED.Then,the feasibility design of the clean process for separating DIPE/IPA/H₂O ternary azeotropes using EG by ED and ED coupled pervaporation（PV）technology is simulated optimized and process enhanced by using the database of Aspen Plus V11and Gabi software.We have completed the process improvement from a three-column dual ED fine separation process to a three-column single ED coupled PV technology for separating DIPE/IPA/H₂O ternary azeotropes.DIPE is obtained through ED,and EG is recycled through conventional distillation.IPA and H₂O are separated through PV technology.The sequential iterative optimization algorithm was used to simulate the operating parameters and optimize the TAC and LCA of four processes,and the optimal process for configuring operating parameters was determined.Compared to the EG-EG+H₂O process,the TAC,GWP and HTP of the EG-IPA+H₂O process decreased by 20.76%,6.11%and 6.11%,respectively,demonstrating excellent energy-saving and emission reduction effects.The combination of novel strict process TAC model and LCA impact model is used to predict and screen excellent entrainer for separating complex azeotropic systems,overcoming the formation of new azeotropes or near boiling point systems between entrainers and heavy components,and avoiding new difficulties in solvent recovery.Clarified the relationship between PECI,LTEDI and the process economy,environmental friendliness and green sustainability of screening entrainer.Elaborated the new principle and mechanism of a model with precise predictive and universal applicability for screening green performance entrainer;It saves a lot of simulation and optimization workload in screening entrainers.The ED+PV coupled process explored in this study achieves the separation of azeotropes using pervaporation membrane separation technology,with the aim of recovering products from the chemical and pharmaceutical industries with higher purity and commercial added value.It has higher industrial application economic value and broad prospects,and more obvious comprehensive performance advantages.A new approach has been established for the separation and recovery of high-purity chemicals in heterogeneous ternary azeotropes of ether/alcohol/water,and even extended to multicomponent azeotropes containing alcohol/water azeotropes.This study provides important theoretical predictive guidance for the selection and application of organic solvents,low eutectic solvents,ionic liquids and their mixed solvents for the evaluation and application of ED separation of quaternary,pentagonal and even more ternary azeotropes.We will provide a competitive cost investigation basis for the improvement and strengthening of clean productive processes in the future chemical and pharmaceutical industries such as isopropyl ether,fine chemicals,isopropanol pharmaceuticals,and wine.It has superior comprehensive performance advantages and huge application prospects of saving comprehensive cost,saving energy and reducing gas emissions,which is conducive to achieving the development goal of carbon neutrality of energy conservation and emission reduction in the chemical and pharmaceutical industries.