Regeneration Of Ionic Liquids Research Articles

Desulfurization of Diesel Using Ionic Liquids: Process Design and Optimization Using COSMO-Based Models and Aspen Plus.

Sulfur dioxide emissions from fossil fuel combustion have been known to cause detrimental health and environmental effects. The currently used hydrodesulfurization (HDS) method employed by refineries has several drawbacks, such as excessive hydrogen consumption, high energy demand, and inability to remove complex organosulfur compounds, which have limited its ability to produce ultralow sulfur diesel (ULSD) at reasonable operating and capital costs. Ionic liquids (ILs) have been widely studied for their potential to replace conventional HDS. However, while their success has been demonstrated at the laboratory level, studies on industrial-scale feasibility and their integration into process simulators such as Aspen Plus are limited. In this work, 26 commercially available ILs have been screened using COSMO-based models and Aspen Plus for the desulfurization of diesel fuel and several possible process configurations have been examined. In particular, the challenge of ionic liquid regeneration, which has largely been ignored in the literature, has also been addressed and several potential regeneration methods have been proposed including extractive regeneration (E-RE) and stripping regeneration using nitrogen and air as stripping media (S-RE). The results indicate that, among the 26 ILs studied, 1-butyl-3-methylimidazolium thiocyanate is the most promising as a solvent for extractive desulfurization (EDS), E-RE, and S-RE. E-RE was found to be more effective for the removal of dibenzothiophene (DBT), while S-RE is more suited to the removal of thiophene and benzothiophene (BT). As a result, an optimized diesel desulfurization process using 1-butyl-3-methylimidazolium thiocyanate has been proposed that achieves ULSD with <10 ppm total sulfur in simulation studies, with complete recycling of the IL and minimal loss of the model diesel.

Separation of polysaccharide and protein by ionic liquid-based extraction techniques

Biopolymers are natural macromolecules obtained from animal, plant and microbial sources, with the potential to be used in a wide range of applications. A key process step, which is still underdeveloped, is the downstream processing. In this work, water immiscible and water miscible ionic liquids (ILs) were investigated regarding their ability to fractionate a mixture of polysaccharide and proteins. Alginate and bovine serum albumin (BSA) were used as model compounds to mimic natural polymer crude extract. Phosphonium ILs composed of different anions (bromide, dicyanamide and phosphinate) were used as water immiscible ILs while imidazolium ILs, combined with phosphate salts to form biphasic system, were selected as water miscible ILs. In water immiscible IL systems, the partitioning behavior of biopolymers depended on IL's anions and there was formation of insoluble precipitate. The insolubility of precipitate in diverse aqueous and organic solvents hindered the processibility of water immiscible phosphonium IL for fractionation of biopolymers. The partitioning of biopolymers in water miscible ILs systems also depended on the IL's anion, as well the concentration of IL. Separation of alginate (yield = 90% and purity = 99%) from BSA (yield = 89% and purity = 99%) was best achieved by the [C4mim]Cl-based extraction system. After fractionation, regeneration of IL and salt used was carried out by ultrafiltration, with recovery yields up to 100%. The high extraction yields and recyclability of phase-forming compounds confirm the potential of water miscible ILs systems to fractionate polysaccharide and protein.

Wood microchannels with multi-carboxyl groups for selective adsorption of Fe3+ from ionic liquids aqueous solution: Experimental and DFT study

Heavy metal contamination is widely present in the spinning field. Some heavy metal ions such as Fe3+ may accumulate in the coagulation bath using ionic liquids (ILs) as green solvents to prepare regenerated cellulose fibers (RCFs), which seriously affect the performance of RCFs and the subsequent regeneration of ILs. This study proposed a new strategy to selectively adsorb Fe3+ from ILs aqueous solution using carboxyl-functionalized wood microchannel (CW). The CW was optimized by citric acid concentration, reaction time, and temperature using carboxyl group contents as an indicator. The physic-chemical properties of CW were characterized, and its adsorption performance for Fe3+ was also evaluated in a water system. Furthermore, the adsorption selectivity of CW for Fe3+ and ILs was investigated. The results demonstrate that the CW had a high adsorption ratio for Fe3+ (94.73%), while that for ILs was 4.20%. The selective adsorption mechanism, in which the Fe3+ is mainly separated from ILs aqueous solution by complexation with carboxyl group, was confirmed by FTIR, XPS, MIP, and DFT calculation. Accordingly, this paper may provide a new strategy to selectively adsorb Fe3+ from ILs aqueous solution, thus offering an economical and efficient method for ILs recovery and water purification.

A Novel Dissolution and Synchronous Extraction of Rare Earth Elements from Bastnaesite by a Functionalized Ionic Liquid [Hbet][Tf2N

Rare earth elements (REEs) are widely used in high-tech industries and are important basic raw materials. Bastnaesite is one of the most important minerals used in the rare earth extraction industry, and the efficient development of it is the key guarantee for the safe supply of rare earth raw materials. In this study, a novel method for dissolving bastnaesite using a carboxyl-functionalized ionic liquid ([Hbet][Tf2N]) is proposed. This innovative method provides a collaborative model with the dissolution and synchronous extraction of rare earth elements during the heating and cooling of the [Hbet][Tf2N]–H2O system. In the heating process, rare earth elements can be dissolved in a weakly acidic environment of ionic liquid without the trouble of HF escaping, and the leaching efficiencies of rare earth elements are above 95%. During the cooling of the leaching system, the rare earth ions in the dissolved state are extracted into the ionic liquid phase due to the two-phase stratification of [Hbet][Tf2N] and aqueous solution. It has been proved that rare earth ions recovery and ionic liquid regeneration can be achieved by back extraction using oxalic acid for the REEs-loaded ionic liquid.

Efficient Biomass Pretreatment Process Based on the Simple Reuse of a Low-Viscosity Ionic-Liquid Solvent System

Ionic liquids (ILs) are expensive, so it is necessary to reuse ILs; however, the reuse process is cumbersome as antisolvents are added and evaporated to regenerate ILs after each biomass pretreatment. Increasing the treatment capacity of biomass before regenerating ILs is desired; however, the high treatment capacity of biomass before IL regeneration and high lignin removal rate are a contradiction in terms. In this paper, a solution was proposed that includes pretreating biomass with a binary system composed of low-viscosity IL 1-ethyl-3-methylimidazole tetrafluoroborate ([Emim][BF4]) and l-arginine (Arg). It was shown that Arg could promote lignin dissolution and inhibit cellulose degradation in [Emim][BF4]. The system could be reused just by vacuum filtration after pretreatment without using antisolvents. After using [Emim][BF4]–Arg five times, the cumulative treatment capacity of corn straw reached 20.55%, while the total removal rate of lignin (84.94%) and the total yield of cellulose (93.23%) remained high. This method is of great significance for the industrial application of biomass pretreatment using ILs.

Dissolution and electrolysis of lunar regolith in ionic liquids

Oxygen extraction from lunar regolith is one of the key in-situ resource utilization methods required for a permanent human presence on the moon. In this work an electrolysis-based extraction method was investigated, which works with innocuous chemicals and at moderate temperatures. EAC-1 was utilized as lunar regolith simulant and the ionic liquid 1-ethyl-3-methylimidazolium hydrogen sulfate was used as electrolyte. The working principle of this method, which was pioneered by Paley et al.2009, is envisaged as a three step process. First, water is generated by the dissolution of regolith in the Brønsted acidic ionic liquid. This water is electrolyzed, yielding oxygen and hydrogen as an intermediate product. Finally, the ionic liquid is regenerated by anodic oxidation of hydrogen and cathodic reduction of the dissolved metal ions. A gravimetric investigation showed that approximately 30 ​wt% of EAC-1 can be solubilized, if at least 6 ​g of ionic liquid are used per gram of EAC-1. Phosphorous oxide was found to be the most soluble compound with 82.0 ± 3.1% of the total amount in solution, followed by MgO, Na 2 O, K 2 O, Al 2 O 3 , iron oxides, TiO 2 and CaO in decreasing order as determined by inductively coupled plasma optical emission spectrometry (ICP-OES). Cyclic voltammetry of the neat ionic liquid revealed that reduction of H + is the dominant cathodic reaction of the electrolyte. The cyclic voltammogram of the EAC-1 solution showed a Fe 2+ /Fe 3+ redox peak pair, yet no distinct current, which could be attributed to further reduction of metal ions and electrodeposition. An investigation of the electrode surfaces with SEM and EDX after potential controlled electrolysis experiments at strongly negative cathodic potentials did not reveal any signs of metal deposition and ionic liquid regeneration. Hence, more work is required to enable the ionic liquid regeneration of this oxygen extraction method by either inhibiting the hydrogen evolution reaction in the ionic liquid electrolyte or facilitating metal deposition. • Investigation of an oxygen extraction method from lunar regolith with electrolysis. • Ionic liquid 1-ethyl-3-methylimidazolium hydrogen sulfate is used as electrolyte. • Approximately 30 ​wt% of the lunar regolith simulant EAC-1 can be solubilized. • ICP-OES analysis revealed P, Mg, Na, K, Al, Fe, Ti and Ca ions in solution. • Hydrogen evolution reaction limits cathodic stability of the ionic liquid.

Removal of Trace Aluminum Impurity for High-Purity GdCl3 Preparation using an Amine-Group-Functionalized Ionic Liquid

Aluminum, as an associated metal with rare-earth resources, is a common impurity in rare-earth separation products. In the traditional P507-kerosene-HCl system, tremendous aluminum impurity (8875 mg/L herein) is often enriched in GdCl3 solutions because of the similar extraction sequence during rare-earth separation. In this work, a new amine-group-functionalized ionic liquid (IL) was developed to remove trace aluminum impurity from high-purity GdCl3 solutions, overcoming the drawbacks of strong hydrophilicity and complicated compositions of the organic phase, as well as other impurities introduced and tremendous saline wastewater produced inevitably. Methyltrioctylammonium hydroxide (N1888OH), instead of the water soluble ammonium hydroxide (NH4OH), was used to dissociate the dimer of sec-octylphenoxy acetic acid (CA12) and synthesize cation- and anion-bifunctionalized IL [N1888][CA12]. The separation factor of Al/Gd was as high as 36. The influences of pH, salting-out agent, extraction time, temperature, and stripping efficiency on the extraction efficiency were evaluated. The result showed that high-purity GdCl3 solution was obtained with low aluminum impurity of 10 ppm after five-stage countercurrent extraction. Due to the weak interaction between the metal and IL, very dilute HCl solution (0.07 mol/L) and NaOH solution (0.07 mol/L) were in favor of metal stripping and IL regeneration.

Hydrodynamics numerical simulation of a vertical falling film evaporator for ionic liquid systems

With a series of advantages, falling film evaporator is potentially appropriate for the purification and regeneration of ionic liquids (ILs). Due to the unique molecular structure of ILs, the IL film in falling film evaporator exhibits special hydrodynamic behaviors compare with organic solvents. The Nusselt method exhibits large deviations in predicting the film thickness and film velocity of ILs, which can be ascribed to the neglect of surface tension. In consideration of surface tension and wall adhesion, a novel simulation model was developed for quantitatively predicting the hydrodynamics of falling film flow. With the proposed model, the film flow distribution, film velocity and thickness were investigated. The predicted film thickness data are in general agreement with the experimental results. A novel empirical film thickness correlation considering surface tension is proposed, with deviations less than ±10%. The hydrodynamic models will provide fundamentals for designing the falling film evaporator of IL systems.

A comparative study between ionic liquid coating and counterparts in bulk for toluene absorption

The structure-activity relationship (SAR) for toluene absorption and desorption in ionic liquids (ILs) has been investigated for seven commercial ILs in bulk and thin liquid layer. ILs with imidazolium cations of different alkyl chain lengths and a Hofmeister series of anions including [CH3COO], [I], [BF4], [HSO4], and [PF6] were included. Absorption capacity for toluene increases with increasing kosmotropicity of the cation and anion, while the absorption rate in bulk ILs is governed by viscosity and that in thin ILs layer by the oil-water partition coefficient (Kow). A regenerability coefficient (Rp) measures toluene desorption and IL regeneration. The release rate as measured by dRp/dt correlates well with the Kow and viscosity of the ILs and tx, the time required to completely desorb toluene is related to its ionic strength as measured from v(C2H) of the imidazolium cation. These properties are in turn governed by the kosmotropicity of the cation and anion pair forming the IL.

Regeneration of [Bmim]BF4 ionic liquid by ozonation: hydrogen bond roles, synergistic effect, and DFT calculation.

Ionic liquids (ILs) are a kind of promising extractants for removing undesirable organics from industrial wastewater and crude oil, etc. Herein, IL regeneration by ozonation was proposed for its recycling. 1-Butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF4) and phenol were used as the representative IL and organic matter, respectively. The regeneration performance, stability of [Bmim]BF4, and roles of hydrogen bonds between O3 and [Bmim]BF4 in the phenol removal were studied. The experimental results showed that 90.2% of phenol was degraded in [Bmim]BF4 after ozonation treatment for 30 min with the O3 concentration of 1.2 mg/L. The nonvolatility of [Bmim]BF4-made phenol was adequately degraded, while the concentration of phenol increased during ozone treatment in the conventional extractants (ethanol, ethyl acetate, and dichloromethane) due to their high volatility. The reuse experiments, spectra of Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance spectroscopy indicated that [Bmim]BF4 was steady under the ozonation process. Density functional theory simulation confirmed that hydrogen bonds between [Bmim]+ and O3 could be formed, and calculational results of Hirshfeld charges indicated that the nucleophilicity of O3 was enhanced by the hydrogen bonds. The enhanced nucleophilicity resulted in the increase of phenol degradation efficiency by ozonation, and the synergistic effect between O3 and ILs was proportional to the hydrogen bond donor ability of ILs.

Accurately-controlled recovery and regeneration of protic ionic liquid after Ionosolv pretreatment via bipolar membrane electrodialysis with ultrafiltration

Efficient recovery and regeneration of ionic liquid is significant for industrial Ionosolv pretreatment. Complicated electrolyte composition restricts the scale-up recovery and application of protic ionic liquid such as triethylammonium hydrogen sulfate [TEA][HSO4] in biomass-related research. Recovery of [TEA][HSO4] after Ionosolv pretreatment for miscanthus powder was studied using bipolar membrane electrodialysis (BMED) assisted with ultrafiltration (UF) by the divisional recovery of TEA+ as TEA and recovery of SO42− as H2SO4 in different BMED compartments. Hence accurately-controlled regeneration of [TEA][HSO4] could be realized. Influence of current density and feed concentration of BMED module was studied in detail. In this study, the highest recovery ratio for TEA+ and SO42− reached 93.7% and 96.4%. The lowest energy consumption of specific [TEA][HSO4] recovery was about 6.2 kwh/kg. Insight gained from this study suggests a potentially industrial methodology for complicated protic ionic liquid recovery after biomass processing.

Effect of regenerated ionic liquid pretreatment on the thermogravimetric analysis of spent coffee ground

ABSTRACT Ionic liquids are regarded as green solvents and found very effective in the pretreatment of biomass and spent wastes. However, the high cost of ionic liquids is a major worry. In this concern, regeneration could be a feasible solution. In this study, the pretreatment performance of fresh and regenerated ionic liquid (tributyl methylammonium chloride) ([N1444] [Cl])) with respect to their thermal behavior was investigated. It was found that fresh and regenerated ionic liquids improved the volatility of Spent coffee ground from 8.53 to 10.69 and 10.62, respectively, and heating values from 17.53 MJ/kg to 17.62 MJ/Kg and 17.71 MJ/kg, respectively. The reactivity for untreated Spent coffee ground (0.024% min−1°C−1) was improved significantly after ionic liquid treatment (0.047% min−1°C−1). The results suggest that the regeneration of ionic liquids could favor the pretreatment of spent wastes that will ultimately lead to an economical industrial operation.

Stripping Columns to Regenerate Ionic Liquids and Selectively Recover Hydrocarbons Avoiding Vacuum Conditions

There is a large number of liquid-liquid extraction processes where ionic liquids (ILs) are proposed as solvents. However, the development of the purification and IL regeneration units still represents a challenge. Several effective separation trains were proposed to regenerate ILs, but extreme vacuum is needed to achieve commercial standards, which demands extra energy and extra solvent consumptions due to recycling streams. In this proposal, the use of stripping columns stands as a promising IL regeneration technology to avoid vacuum conditions and to enhance the separation of the compounds that form the extract stream, explored in the aromatic-aliphatic separation. COSMO-based/Aspen Plus methodology is applied to extensively evaluate the role of the IL nature and easily evaluate the influence of the main operating variables, namely temperature feed, column pressure, reboiler heat, number of stages on the separation efficiency. A critical comparison between current proposal and the benchmark IL regenera...

Energy Analysis of Physical Absorption and Chemical Absorption of CO2 in Ionic Liquids

CO2 solubility in ionic liquids (ILs) is measured extensively to develop IL‐based technology for CO2 capture. Herein, the choline‐ and acetate‐based ILs are selected as the studied physical and chemical absorbents for CO2 capture, respectively. The CO2 solubilities in choline‐ and acetate‐based ILs are thermodynamically modeled. The ILs consumed for CO2 absorption and the energy demands for the ILs regeneration are calculated and compared with those of the conventional imidazolium‐based ILs. The results show that the three choline‐based ILs are not energy saving in the pressure‐swing process. In the temperature‐swing process, the energy demand for CO2 absorption by using acetate‐based ILs reveals that the chemical absorption‐based ILs are the absorbent with lower energy demands compared with the physical absorption‐based ILs.

Demonstrating the key role of kinetics over thermodynamics in the selection of ionic liquids for CO2 physical absorption

A comprehensive study of over 50 ionic liquids (ILs) -integrating molecular simulation, gravimetric experiments and process analysis- has been conducted to evaluate the role of thermodynamics and kinetics on the physical absorption of CO2 by these widely researched solvents. Despite the common view, CO2 molar gas solubility is found as a misleading criterion to select the adequate IL for being used as CO2 absorbent in commercial separation columns, due to the strong kinetic control of the operation. In contrast, low viscosity and molar weight are demonstrated to be key parameters to minimize solvent consumption, energy duty and equipment size. Short-chain imidazolium-based ILs with tetracyanoborate, tricyanomethanide, and dicyanamide anions are proposed as adequate CO2 absorbents with favorable transport and thermodynamic properties. Current results indicate that ILs do not exhibit better absorbent performance in the CO2 capture unit than conventional organic solvents (such as glymes, components of Selexol) already used in the industry. IL regeneration stage need to be considered in future studies in order to state the promising advantages of IL absorbents in terms of thermal stability, energy consume and economy.

Petron to use Honeywell UOP technologies to increase Limay aromatics production

The ionic liquids (ILs) have been widely studied as potential replacements of conventional solvents in the extraction of aromatic hydrocarbons from alkanes. However, most of the literature is focused in obtaining liquid-liquid equilibria experimental data without studying the complete extraction and IL regeneration process. In this paper, a computer-aided methodology combining COSMO-based molecular simulations and Aspen Plus process simulations has been used to study the extraction process of aromatic hydrocarbons from pyrolysis gasoline employing a binary mixture of 1-ethyl-4-methylpyridinium bis(trifluoromethylsulfonyl)imide ([4empy][NTf2]) and the 1-ethyl-3-methylimidazolium dicyanamide ([emim][DCA]) ILs as solvent. An extensive comparison (more than 600 points) between experimental data and the predictions obtained by the COSMO-based thermodynamic model of liquid–liquid and vapor–liquid equilibria and ILs physical properties was made for validation purposes. Process simulations were performed in three system configurations: with one, two, or three flash distillations in the IL recovery section. The potential advantage of using binary IL-IL mixture as extracting solvent was studied in the whole range of composition. The configuration with three flash distillations and the binary IL-IL mixture with a 75% of [4empy][NTf2] were selected as the optimal conditions to increase aromatic recovery and purity, improving the separation performance respect to the neat ILs.

Extractive Distillation of Acetone – Methanol Mixture using 1-Ethyl-3-methylimidazolium Trifluoromethanesulfonate

Acetone and methanol are organic solvents widely used in industry. Acetone with methanol forms a homogeneous minimum-boiling azeotrope which is not separable by conventional distillation processes. A common method for its separation is the extractive distillation in the presence of a selective solvent (such as water). In this paper, the use of an ionic liquid (1-ethyl-3-methylimidazolium trifluoro methanesulfonate [Emim][triflate]) for acetone–methanol separation by extractive distillation was designed. The aim of the design calculation was to obtain acetone with the purity of 99.5 mol % and methanol with the purity of above 99.0 mol %. Calculations were carried out in a proprietary program constructed in Matlab® by solving a set of material balances at individual theoretical stages of the distillation column combined with the vapor–liquid equilibrium (VLE) of the ternary system acetone–methanol–[Emim][triflate]. For the description of VLE of the above mentioned system, the NRTL equation was used. Several optimization cycles were done resulting in optimal parameters of the extractive distillation column (number of theoretical stages, solvent consumption, reflux ratio and position of the feed stage) in regard to the required purity of products (acetone and methanol). Regeneration of ionic liquid was provided by evaporation at the low pressure of 20 kPa. The heat and cooling consumption duties of the designed separation process were analyzed. Regeneration of the ionic liquid is energy-demanding compared to the separation of acetone–methanol in an extractive distillation column. The heat consumption is only 11 % of the heat used up by the whole separation process.

A combination desulfurization method for diesel fuel: Oxidation by ionic liquid with extraction by solvent

Ionic liquids (ILs) are intensively studied in the oxidative desulfurization of diesel fuel, where ILs act as both extractants and catalysts with adding another oxidant such as H2O2 solution. Some thiophenic sulfur compounds can be effectively removed from some model diesel fuels with this method, while it is hard to reduce the sulfur content to a desirable level like less than 10 ppm with this method when people investigated the real diesel fuels. In this work, we developed a new combination desulfurization method, first oxidative desulfurization by ILs as both extractants and catalysts with 30 w% H2O2 as oxidant, then followed by desulfurization by solvent extraction. Four ILs and ten solvents were investigated for real diesel fuels. The effects of different factors on desulfurization performance were systematically studied, e.g., ILs species, solvents species, temperature, time, IL/oil mass ratio, extractant/oil mass ratio, multiple desulfurization, regeneration of ILs and solvents. The results show such a combination method is effective to reduce the sulfur content in real diesel fuels to a desirable level, e.g., the sulfur content in FCC diesel fuel was reduced to 8.1 ppm from original 150 ppm after one step oxidation by [(CH2)4SO3HMIm][Tos] (ILs/oil mass ratio of 1/2; 3 h, 348.15 K, O/S molar ratio of 40/1) and two-step extraction by DMF (extractant/oil mass ratio 1/2, 30 min, 298.15 K). ILs and solvents can be regenerated and recycled with negligible activity loss.

Energetic aspects of imidazolium-based ionic liquid regeneration from aqueous solutions

Separation processes are common in chemical industry. Higher prices of energies and environmental threats led to increased interest in the design of new and the optimization of real technologies. As an example, the effort to replace conventional solvents in extractive distillation and liquid extraction can be used. In the last years, ionic liquids have emerged as suitable alternative solvents. The presented work deals with the separation of a tert-butyl alcohol–water mixture by extractive distillation using a methylimidazolium-based ionic liquid (1-ethyl-3-methylimidazolium bromide, [EMim]Br). For the ionic liquid regeneration from its aqueous solution (bottom product from the extractive distillation column working at atmospheric pressure), an alternative separation method, evaporation at reduced pressure, was assumed. Two case studies of ionic liquid (IL) regeneration were evaluated. In the first case, pressure of the liquid bottom stream was reduced by passing through a throttle valve and the created vapor–liquid stream entered an evaporator in which the extraction solvent is pre-concentrated to be re-used in the extractive distillation column. In the second case, after the pressure reduction in the throttle valve, the vapor phase (pure water steam) was separated in a phase separator, and the stream entering the evaporator was the concentrated liquid mixture of [EMim]Br with water. Both regeneration procedures were analyzed for the heat and cooling consumption duty and compared to that corresponding to IL regeneration by distillation.

Separation of methyl acetate methanol azeotropic mixture using 1-ethyl-3-methylimidazolium trifluoromethanesulfonate

In this work, potential use of ionic liquid 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([Emim][triflate]) in the extractive distillation of a methyl acetate–methanol mixture forming an azeotrope was studied. The primary objective was to design the separation process for the production of highly concentrated methyl acetate. The process is proposed to be run in two distillation columns, an extractive distillation column and a regeneration column for the ionic liquid (IL) solvent recovery. Within the design calculation of the extractive distillation column, column parameters such as the number of theoretical plates, position of the feed input plate, solvent consumption, and reflux ratio for the required content of methyl acetate (MA) in the distillate (99.5 mole % of MA) were optimized. The objective of the IL regeneration was to obtain highly concentrated IL (more than 99 mole % of IL). For IL regeneration, a distillation column was proposed. Operating conditions of the regeneration column such as pressure and thermal conditions of feed (temperature and vapor-to-liquid mole ratio) were optimized. For the regeneration column, the number of theoretical plates, reflux ratio, and position of the feed input plate were determined. To represent the vapor–liquid equilibrium (VLE) of the ternary system at the atmospheric pressure and binary VLE at reduced pressures, the original NRTL model was used; its parameters were evaluated from the VLE data of the corresponding binaries taken from literature. Based on the results of columns simulation, heat consumption required in the extractive and regeneration column reboilers and condensers was evaluated. In conclusion, energy-saving alternatives are proposed.