Number Of Theoretical Stages Research Articles

Solvent extraction of La, Nd, and Eu using a newly designed solutions spray system

This research covers a new continuous solvent extraction “solutions spray system” technique to extract lanthanum (La), neodymium (Nd), and europium (Eu) from chloride solution using DEHPA. This setup enhanced the extraction kinetics and mass transfer compared to the conventional mixer-settler by generating micro-sized droplets of the feed streams in the mixing chamber, causing speedy and better mass transfer, and the special design of the settling column boosted the separation process with improved quality products. Variables like pH, DEHPA concentration, ionic strength, and aqueous/organic phase ratio were studied to determine the performance of this setup. At the optimum values of these variables (2.0 pH, 0.303 M DEHPA, and 1.54 mol/L ionic strength), the percent extraction of La, Nd, and Eu was 95.03 %, 99.36 %, and 99.98 %, and the distribution ratio was 19.14, 155.25 and 4165 respectively, which showed the extraction in a single stage. Furthermore, the values of separation factors, SFEu/La = 6.69, SFEu/Nd = 5.33, and SFNd/La = 1.26 at 0.50 pH, showed the selectivity of these elements. Later on, McCabe Thiele diagrams were plotted for extraction and stripping sections to see the minimum number of theoretical stages for the complete recovery of REEs and their selective separation from each other.

Development of a customized computer Program for the construction of ternary diagram for liquid-liquid extraction process

The Liquid-Liquid Extraction (LLE) is a liquid-liquid phase mass transfer process in which solute chemicals are transferred between two immiscible or partially miscible liquids due to difference in solubility of the solutes in the two liquids. The phase equilibrium relationships are generally inconvenient to handle algebraically, therefore, LLE computational analyses are usually made graphically. Manual construction of ternary diagram becomes cumbersome, tedious and time consuming when used for a process that requires large number of stages. Therefore, the aim of this work was to develop a customized computer package for the ternary diagram. The customized computer package for the ternary diagram construction was achieved with the use of fuzzy inference system toolbox and primitive line function in MATLAB. The computer program was test-run using data from literature to determine theoretical number of stages for a given LLE separation process. The result compared well with the existing literature result.

Process design and simulation of methyl isobutyl ketone (MIBK) dehydration by batch distillation: A study on unit configuration and operational policies

Heteroazeotropic batch distillation of methyl isobutyl ketone-water binary mixture is investigated, seeking a reliable operation for dehydration of methyl isobutyl ketone (MIBK). The dynamic batch distillation module (BatchSep) of the commercial package Aspen Plus V.12.1® is applied for simulations. An initially fed unit at atmospheric pressure is simulated from the heating-up step until it reaches the desired MIBK purity of 99.8 wt%. Three configurations, namely conventional batch distillation unit (Mode I), batch distillation unit with decanter (Mode II), and a simple distillation unit (Mode III), are compared in a wide range of operating conditions. The effects of condenser temperature and the number of theoretical stages are also examined. According to the results, applying a decanter (Mode II) with a return fraction of over 0.75 for the MIBK-rich phase and below 0.4 for the aqueous phase provides higher MIBK recovery than the maximum achievable value in a conventional unit (Mode I), with almost no increase in process time. A perfect decanter offers an almost complete MIBK recovery, which is about 5% over the maximum value by conventional units (Mode I). Moreover, cutting the reflux (Mode III) offers the fastest way to the desired product but provides the lowest MIBK recovery value. The aqueous phase return fraction does not significantly impact MIBK recovery, but if it exceeds 0.5, it remarkably affects the process time/energy cost. When maximum MIBK recovery rate/minimum energy cost is desired, applying a decanter (Mode II) with a return fraction above 0.5 for the MIBK-rich phase and below 0.55 for the aqueous phase yields a higher production rate and a lower energy cost per unit quantity of product compared to the best achievable values for a conventional unit (Mode I). A perfect decanter improvesproductionrateandenergyefficiencyby8 %overthe best case in a conventionalunit (ModeI). Also, operation without reflux (Mode III) is preferred over a conventional operation (Mode I) with a total return fraction over 0.7 due to its superior energy efficiency and production rate.

ИЗВЛЕЧЕНИЕ БУТАДИЕНА ТРЕБУЕМОЙ ЧИСТОТЫ ИЗ БУТЕН-ДИВИНИЛЬНОЙ ФРАКЦИИ С ПОМОЩЬЮ ЭКСТРАКТИВНОЙ РЕКТИФИКА-ЦИИ

The operating modes of a distillation column with a fixed number of theoretical stages, ensuring the required extraction of butadiene from the butene-divinyl fraction, are considered

Experimental investigation on nontoxic solvents for separation of vanillic acid

AbstractBACKGROUNDVanillic acid, an aromatic carboxylic acid and a derivative of vanillin, is used as an additive in consumer goods for its aroma. Previously, most vanillic acid was produced through a petrochemical route, but as a consequence of stringent environmental policies, it is now produced by the biotransformation of ferulic acid. Vanillic acid is also found in the wastewater streams of paper‐pulp industries and olive‐oil mills. So, recovering vanillic acid from fermentation broth, either during bioproduction or from a wastewater stream, while minimizing toxicity, is a difficult task. In order to reduce the toxicity substantially, bio‐based solvents such as sunflower, mustard and rice bran oils were employed as diluents along with tri‐n‐butyl phosphate (TBP) as extractant in order to recover vanillic acid by reactive extraction.RESULTSThe extraction performance was elucidated using terms such as distribution ratio, extraction efficiency, loading ratio and equilibrium complexation constant for different extractant–diluent combinations. The highest extraction efficiency and distribution ratio for the different solvents were in the following order: TBP + sunflower‐oil (72.02%–92.47%; 2.57–12.29) > TBP + rice bran‐oil (65.56%–90.55%; 1.90–9.58) > TBP + mustard‐oil(64.03%–89.87%; 1.78–8.87). The theoretical number of stages was determined as 4 to achieve a targeted extraction efficiency of 90%; these predictions were borne out experimentally.CONCLUSIONIn this study, vanillic acid was recovered from the aqueous phase using tri‐n‐butyl phosphate in sustainable, environmentally friendly, bio‐based solvents such as rice bran oil, sunflower oil and mustard oil. © 2024 Society of Chemical Industry (SCI).

Simulation study of reactive distillation process for synthesis of dimethyl maleate

Abstract Conventional dimethyl maleate (DMM) synthesis relies on the use of sulfuric acid as a catalyst which requires water washing and produces a large amount of wastewater that harms the environment. The use of this method is expensive since it involves numerous processes such as neutralization of sulfuric acid, washing with water, distillation etc. and the yield of dimethyl maleate is not very high. Reactive distillation integrates the two important industrial processes such as reaction and distillation into a single unit which shortens the overall process, reduces capital and operating costs, and maintains the reaction in a forward direction to enhance the conversion of maleic anhydride by continuously removing of the products. In this work, simulation study based on experimental investigation of reactive distillation process for the synthesis of dimethyl maleate was carried out using Aspen Plus V11. DZH strong cation exchange resin was used as catalyst for esterification reaction of maleic anhydride with methanol. A reactive section of column was packed with Katapak SP type packing loaded with DZH catalyst while non-reactive sections consist of wire gauze packing. In order to describe a reactive distillation process for synthesis of dimethyl maleate, RAD-FRAC equilibrium stage model was employed. The NRTL activity model and RK equation of state model were selected to describe vapor-liquid equilibrium of the system. The reliability of the developed simulated model was verified by validating the simulation results with the experimental ones. The effect of various design and operating parameters on the conversion of maleic anhydride and purity of dimethyl maleate has been studied. It was found that the optimal condition for RD, were as follow: total number of theoretical stages 17, rectifying stages 3, reactive stages 7, stripping stages 5, reflux ratio 0.25, operating pressure 0.1 MPa, reboiler duty 250 Cal/Sec, feed mole ratio 1:5. Under optimized condition the water formed as a results of esterification reaction was constantly removed from the reactive section of the column to maintain reaction balance, the conversion of maleic anhydride was 99.95 %, purity of dimethyl maleate achieved was 0.997 and the reactive distillation process was feasible to produce dimethyl maleate without any wastewater.

Preparation of refined phosphoric acid with recycling of raffinate acid by the extraction of metal impurities

Solvent extraction is the most effective method to remove impurities from wet-process phosphoric acid (WPA). However, the raffinate acid produced by this method cannot be effectively utilized because of a high impurity content and high viscosity, resulting in the waste of phosphorus resources. In this paper, a new process is proposed for extracting metal impurities and purifying the raffinate acid, and utilizing purified raffinate acid to prepare refined phosphoric acid. The effects of the extraction temperature, volumetric phase ratio (R), extraction time, and agitation speed on the metal-ion extraction were investigated. The MER (mass ratio of the sesquioxide content to the P2O5 content, MER = w(Fe2O3 + Al2O3 + MgO)/w(P2O5)) of the raffinate acid was reduced from 0.1516 to 0.1001 under the optimum conditions: temperature = 60 °C, R = 6, reaction time = 30 min, and agitation speed = 500 rpm. More than that, the MER value was reduced to 0.0357 through five-stage cross-current extraction. The theoretical number of stages to reduce the MER of the raffinate to 0.086 was obtained by the McCabe-Thiele method and found to be two stages. Finally, the purified raffinate acid obtained in the pilot experiment was used to prepare refined phosphoric acid, of which the product quality reached food-grade. In addition, the phosphorus yield of the whole process was 95.5%. The application of this new process will significantly improve the recovery ratio of phosphorus in refined phosphoric acid industry.

Flowsheets for hydroxyacetone–phenol binary mixture separation: The use of special distillation methods

Objectives. To study the possibility of hydroxyacetone–phenol binary mixture (a constituent of a mixture of phenol production by the cumene method) separation in flowsheets based on the use of distillation special methods. This is the addition of separating agents to increase the relative volatility of the components of the original mixture, and the variation of pressure in the columns.Methods. A computational simulation in Aspen Plus® was used as the research method. Mathematical modeling of the vapor–liquid equilibrium was carried out using a local compositions model Non-Random Two Liquid. The viability of the latter was confirmed by comparing experimental and calculated on phase equilibrium data, and azeotropic data. The average relative error does not exceed 3%.Results. The dependence of the composition and boiling point of the hydroxyacetone–phenol azeotrope on pressure was determined in a computational experiment (as the pressure increases, the azeotrope is enriched with phenol). The possibility of using a complex of columns operating under different pressures to separate the mixture was shown (the shift of the azeotrope is about 9%). The change in the relative volatility of components of the original mixture in the presence of a high(diethylene glycol) and a low-boiling (acetone) separating agent was investigated. Both solvents are selective agents used in extractive and re-extractive distillation processes. Three technological separation flowsheets containing two distillation columns were proposed.Conclusions. The study established the operation parameters of the columns (number of theoretical stages, feed stages of the original mixture and separating agent, and reflux ratio) and energy consumption (total heat supplied to the columns boiler) of three separation flowsheets ensuring the production of products of a given quality (not less than 0.99 mol fractions). The flowsheet with diethylene glycol is characterized by the lowest energy consumption. It is recommended that complexes of extractive and re-extractive distillation be further optimized. This enables the second product of cumulus production—acetone—to be involved in the technological cycle.

A mapping method for quick assessment of reactive distillation applicability to ternary reaction systems

Reactive distillation (RD) is a process intensification technology that offers opportunities in the chemical industry. However, designing RD columns remains a demanding task as reaction and separation phenomena occur simultaneously in the column. Moreover, in the early phase of conceptual process design, most of the physical and chemical properties information is unknown. Aiming to deal with that constraint, this paper presents the latest development of a mapping method, for the quick evaluation of the RD applicability. Initially, the approach was introduced in our previous work but limited to quaternary reaction systems. The extended method development performed in this work shows the general suitability of the method for ternary reaction systems, in spite of decreased degree of freedom of the systems. The method validation based on an industrial case study shows that the deviations for predicted number of theoretical stages and reflux ratio are less than 10%. Using only generic cases with fixed representative relative volatilities, chemical equilibrium constant and the Damköhler number, end users of the mapping method can quickly perform the RD applicability screening without doing any extensive rigorous simulations for real systems.

The Aptness of Organic Diluents with Tri‐n‐Butyl Phosphate for Liquid‐Liquid Equilibria of Acrylic Acid

AbstractSeparation of carboxylic acids from downstream is a bottleneck in the chemical industry since it takes nearly 30–50 % of the overall production cost. In view of this, an attempt was made for the extraction of acrylic acid from aqueous solution with tri‐n‐butyl phosphate dissolved in organic diluents like benzene, toluene, xylene, hexane, and petroleum ether. The results are explained in terms of distribution coefficient (σ), extraction efficacy (η%), equilibrium complexation constant (Kε), loading ratio (ϕ), and coextraction of water. At lower concentration of acrylic acid and higher concentration of tri‐n‐butyl phosphate for the acrylic acid‐tri‐n‐butyl phosphate system, maximum extraction efficacy and distribution coefficient for benzene was found as 88.60 % and 7.772, respectively. Coextraction of water in the extract phase and law of mass action were discussed, too. Diffusivity of acrylic acid to the interface of extract (organic) and raffinate (aqueous) phases was calculated using the Wilke‐Chang equation and Reddy‐Doraiswamy equation. In view of designing a continuous extraction column, the number of theoretical stages and minimum solvent‐to‐feed ratio were also determined.

Process design, simulation and experimental studies of heteroazeotropic batch distillation for phenol dehydration

Phenolic compounds are important groups of chemicals with many applications. Due to the strong affinity between phenols and water, the dehydration of phenolic compounds is often necessary and inevitable. The conventional method for phenol dehydration is the direct distillation without entrainers, leading to high phenol concentration (2–5 wt%) in wastewater and significant difficulty in subsequent wastewater treatment. In this work, heteroazeotropic batch distillation was studied by simulations and experiments to remove water from water-bearing phenols. By simulation, effects of entrainer type, operating pressure, number of theoretical stages, entrainer amount and decanter hold-up on dehydration efficiency were studied in detail. The results showed that the heteroazeotropic batch distillation using ethylbenzene as the entrainer yielded desirable dehydration results with many advantages. The wastewater generated in the dehydration process showed a much lower content of phenolic compounds than the direct distillation, greatly reducing the cost and difficulty of wastewater treatment. The energy consumption of heteroazeotropic distillation was also lower than the direct distillation. Batch distillation experiments were performed to validate the reliability of simulation results. The experimental results were in high agreement with simulations. The produced phenol products showed a water content of 470 ppm, and the content of phenolic compounds in wastewater was reduced to as low as 5.0 ppm. The heteroazeotropic batch distillation proposed in this study suggested an ideal strategy for phenol dehydration which is economically feasible and environmental-friendly.

Optimized conditions for the design and operation of a vacuum distillation column for the purification of crude glycerol from biodiesel production

AbstractDue to the growth in global demand for biodiesel, there is a tendency for the volume of its main by‐product, glycerol, available on the market to increase. This has led to a search for new uses for this by‐product and the development of new processes that use glycerol as a raw material because it has wide industrial applications. However, to be used in many of these processes, the glycerol must go through a purification stage before reaching the purity required for the application (which can reach 99.7% w/w). Taking this into account, the optimization of the parameters for the main glycerol purification stage (vacuum distillation) is essential to reduce the cost of this stage as much as possible. In this article, optimization of the vacuum distillation column was carried out using an artificial neural network (ANN) and a genetic algorithm (GA) together. With the optimization, it was found that four theoretical stages of equilibrium (separation) is the optimal value, in economics terms, for the distillation column on an industrial scale, leading to better performance (in terms of glycerol purity) than patents that used a smaller number of theoretical stages and an equal performance in relation to the patents that used a greater number of stages, which in this case reduces the cost with the size of the column. This result helps to increase the financially viability of using glycerol as a raw material, which can make several processes cheaper, thus generating greater added value to this sustainable by‐product. © 2023 Society of Industrial Chemistry and John Wiley & Sons Ltd.

Determining catalyst loading in reactive distillation column

The widespread industrial application of reactive distillation technology is inseparable from the development of catalytic packing. However, systematic research on the heterogeneous catalyst loading in the reactive distillation column is vacant, and existing studies about catalyst loading on each stage and their distribution ignore the physical structure of the reactive distillation column. In this work, Modular Catalytic Structured Packing combining catalyst bags and structured packing sheets is applied in the modeling and optimization of reactive distillation processes. The catalyst loading on each stage is obtained from three parameters: the catalyst volume fraction of catalytic packing, the catalytic distillation column diameter, and the height of the theoretical stage. Using the effective diffusivity method, a simplified non-equilibrium stage model is chosen to simulate the reactive distillation process, and the bubble-point method for solving the non-equilibrium stage model’s equation system is introduced. The genetic algorithm optimizes both catalyst volume fraction and the number of theoretical stages in the reactive section. Case studies of methyl acetate esterification and ethyl tert-butyl ether (ETBE) synthesis show that greater theoretical stages of the reactive section and enough reflux ratio will reduce the demand of catalysts. Redistribution of catalyst is implemented by dividing the reactive section into several. The non-uniform distribution of catalyst will reduce both energy consumption and catalyst amount for the methyl acetate system, but insignificant for ETBE synthesis, due to different interactions of reaction and separation.

Reaction-assisted separation of acetone from the azeotrope of methanol and acetone

The separation of methanol–acetone azeotrope has been a challenging issue. Methanol in the azeotrope was selectively transformed and removed in this paper. Under mild conditions, 95.5% of methanol was transformed into methyl phenylcarbonate (MPC), phenol and dimethyl carbonate (DMC), while acetone was not converted. The separation process of reaction products was simulated, and 99% of acetone with purity of 99.3 wt% was recovered. The byproducts phenol and DMC were also recovered with purity of 93 and 76 wt%, respectively. Compared to the typical pressure-swing and extractive-distillation schemes, the total number of theoretical stages and heat duty could be reduced by 27.7–38.3% and 48.6–58.4%, approximately. The results of thermodynamic experiments showed that the apparent equilibrium constant (124.4 at 23.1 °C) in the first step was much larger than that (12.9) in the second step, indicating that the intermediate MPC was very stable, and thermodynamic factors originating from the specific coplanar structure of substrate contributed to the high methanol conversion. The transesterification reactions were endothermic and spontaneous due to the positive ΔH and negative ΔG values. The spontaneity of reactions was attributed to the increase of entropy, for which the reason was the more possible spatial distributions of atoms in the products. This paper is beneficial for the separation of alcohols from various aprotic solvents.

Experimental, equilibrium modelling, and column design for the reactive separation of biomass‐derived 2‐furoic acid

AbstractElectrochemical conversion of biomass to value‐added chemicals has gained impetus in recent years. Herein, we present a methodology for recovering biomass‐derived 2‐furoic acid from the dilute aqueous stream by reactive extraction. The reactive extraction was performed using a chemical extractant, trioctylamine (TOA), with diluents (octanol, chloroform, and diethyl ether). Equilibrium parameters influencing the recovery of 2‐furoic acid were evaluated. Using TOA in various diluents, the 2‐furoic acid was recovered with 85%–99% efficiency. A 1:1 complex of the 2‐furoic acid—TOA was formed in the organic phase, and the experimental equilibrium complexation constant was compared with that obtained from the relative basicity and Langmuir models. The equilibrium parameters were used for column design to estimate the solvent to feed ratio (S/F) and the number of theoretical stages (NTS). The NTS required is 12 to attain 99% recovery of 2‐furoic acid in counter‐current extraction. The present study sheds light on the reactive extraction process adopted for process intensification with electrochemical conversion, paving the way for the commercialization of valuable products obtained from biomass.

Performance of alcoholic solvents in the continuous countercurrent spent coffee grounds oil extraction

Ethanol and isopropanol, absolute (ET0, IPA0) and hydrated with 6 and 12 water mass% (ET6, IPA12), were evaluated as solvents in the oil extraction from spent coffee grounds (SCGO). Alcohols' performance evaluation was based on the SCGO partitioning between extract and raffinate phases and the extractor design. An SCGO concentration limit in systems containing ET indicates extract phase saturation. In this case, a Langmuir-type equation provided a satisfactory SCGO partitioning data mathematical description, while the IPA data presented a linear behavior. The increase in temperature from 60 to 80 °C did not affect SCGO partitioning when IPA0 was used as a solvent. ET6 required higher solvent proportions concerning SCG, leading to extractors with a higher number of theoretical stages. The minimum flow rates of ET6 were 1.9 times higher than those required by ET0 and IPA12 and up to 3.2 times higher than the IPA0 flow rate at 60 °C. At 80 °C, the SCGO extraction performance with ET0 and IPA0 was similar. A solvent-to-feed ratio of at least five must be used when an extractor with five theoretical stages operating at 80 °C is considered. In this case, extracts with about 5 mass% of SCGO are obtained.

Design and optimization of VOC control process for tail gas in Rectisol unit based on steady state and dynamic simulation

Rectisol wash process(RWP) is a common process in coal chemical purification unit. However, the CO2 product gas and tail gas in the RWP carries volatile organic methanol, which must be controlled to meet the environmental protection requirements. This work develops a steady and dynamic model for the process of water washing tower(WWT) by Aspen Plus, which is used in Rectisol wash tail gas treatment. The effects of the theoretical stage number(TSN) and desalting water flow rate(FRdw) of the washing tower on the methanol concentration in tail gas(cMET) are studied through sensitivity analysis. The optimized TSN and FRdw of WWT are 16 stages and 15 t/h, respectively. The cMET is 4.1 mg/Nm3 under the optimal condition. The internal structure of WWT is optimized. The design of the WWT is verified by the hydraulic results and dynamic process simulation. The results help to efficiently and conveniently implement the control of volatile organic methanol from RWP.

Mixed Ionic Liquids as Entrainers for Aromatic Extraction Processes: Energy, Economic, and Environmental Evaluations

Experimental measurements for the vapor–liquid equilibria (VLE) of benzene + 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][NTf2]), benzene + 1-ethyl-3-methylimidazolium ethylsulfate ([EMIM][EtSO4]), and benzene + mixed ionic liquids (ILs) (equimolar [EMIM][NTf2] + [EMIM][EtSO4] mixture) are performed. The non-random two liquid (NRTL) model binary interaction parameters are then obtained by fitting the new VLE data and the liquid–liquid equilibrium data previously reported. The interactions between chemical species are analyzed using quantum chemical calculations and the COSMO-SAC method, and it is found that the interactions between benzene and ILs are strongly attractive. Taking as a reference the industrial process that uses sulfolane as the entrainer, several novel industrial processes are proposed, which involve either pure ionic liquids [EMIM][NTf2] and [EMIM][EtSO4] or their mixtures as the extractant for separating aromatic hydrocarbons (benzene) and paraffins (n-hexane). The optimal operating parameters, such as the number of theoretical stages, the extractant-to-hydrocarbon feed ratio, the reflux ratio, and the feed stage, are determined for the different processes. Steady-state process simulations are performed to evaluate the total annual cost (TAC) and the environmental impact (carbon dioxide emissions). It is shown that significant savings in energy consumption (reduction of 19.6–48.7%), TAC (reduction of 6.3–27.1%), and CO2 emissions (reduction of 17.8–47.6%) can be achieved for the processes that use IL extractants, compared to the process based on sulfolane extractant. The proposed IL extractant and the corresponding process are promising alternatives to conventional solvents and processes for aromatic extraction.

Recovery of nicotinic acid (Niacin) using hydrophobic deep eutectic solvent: Ultrasonication facilitated extraction

Hydrophobic deep eutectic solvents (DES) have emerged as alternative environment friendly solvents. Here, DES was prepared using menthol (M) and trioctylphosphine-oxide (TOPO) in the molar ratio of 1:1 and 2:1 to extract nicotinic acid from its aqueous solution ultrasonically. At a molar ratio of 1:1, DES solidified whereas 2:1 remained in the liquid form at room temperature. Physical properties of DES (density, refractive index, and surface tension) were determined. TGA and FTIR analysis were also performed. The highest extraction efficiency (88.33%) and distribution coefficient (7.8) were observed with 0.01 M acid concentration. The used DES was used for 5 successive cycles without regeneration and was further regenerated using 1 N NaOH. The parameters of the extraction column like number of theoretical stages, minimum solvent to feed ratio, diameter and height were proposed for the extraction of nicotinic acid.

Transesterification reactive extractive distillation process using ionic liquids as entrainers: From molecular insights to process integration

In this work, the transesterification reactive distillation coupled with extractive distillation process for n-propanol (PROH) and methyl acetate (MEAC) was developed based on pseudo homogeneous kinetic parameter model using ionic liquids (ILs) as entrainers. The COSMO-RS model was used for screening ILs entrainers. Here, 1-ethyl-3-methylimidazolium acetate [EMIM][AC] was selected as a potential entrainer due to its excellent solvent capacity and selectivity. Further, the COSMO-RS model was performed to calculate the polarization charge density (σ-profile) of methanol (MEOH), methyl acetate and [EMIM][AC], and to explore the molecular polarity. Based on quantum chemistry (QC) theory, the interaction energy between different molecular pairs is calculated. Independent gradient model (IGM) analysis identifies the interaction types of molecular pairs from the perspective of visualization. Owing to the strong hydrogen bond between anion [AC]− and MEOH, the extractive distillation process performance was significantly improved. Based on Aspen Plus platform, the effects of the theoretical stage number, reflux ratio, feed position and entrainer dosage on the cost and energy consumption of the new process was investigated. Based on the sensitivity analysis method, the operating conditions were optimized. Compared to the conventional process, the new reactive distillation coupled with extraction distillation process has higher energy efficiency and lower economic cost. The new process can save the total annual cost of about 3.42 × 105 $/year.