scholarly journals SELECTION OF EXTRACTIVE AGENTS FOR THE SEPARATION OF CHLOROFORM - METHANOL - TETRAHYDROFURAN MIXTURE

2018 ◽  
Vol 13 (3) ◽  
pp. 30-40 ◽  
Author(s):  
V. M. Raeva ◽  
D. I. Sukhov
Keyword(s):  
Energy Consumption ◽  
Extractive Distillation ◽  
Industrial Test ◽  
Ideal Behavior ◽  
Component Mixture ◽  
Distillation Columns ◽  
Boiling Points ◽  
Derivative System ◽  
Separating Agents ◽  
Chloroform Methanol

Variants of the extractive distillation of chloroform - methanol - tetrahydrofuran equimolar mixture with industrial separating agents are considered. The basic system shows opposite deviations from the ideal behavior, because it contains binary azeotropes with minimum and maximum boiling points (3.3.1-4 system according to Serafimov’s classification). The choice of selective substances for extractive distillation was carried out taking into account the concentration dependences of the excess molar Gibbs energy of the binary constituents of the derivative system “chloroform - methanol - tetrahydrofuran - industrial test agent (ethylene glycol (EG), dimethyl sulfoxide (DMSO), N-methylpyrrolidone (N-MP))” at 101.32 kPa. Based on the results of the evaluation of the thermodynamic criterion, DMSO and N-MP are recommended. Both agents show selective effect when separating two binary constituents. EG is selective only with respect to chloroform-tetrahydrofuran mixture. Since the tested agents show different selective effects, the final agent choice determines the qualitative composition of the product flows in the column for the extractive distillation of the three-component mixture (the first column of the flowsheet) and, accordingly, the structure of the total flowsheet. The schemes consist of two two-column complexes for extractive distillation (for the basic three-component mixture and for the binary mixture). The maximum contribution to the total reboiler energy consumption of the distillation columns is made by the first extractive distillation column: 65% (EG), 53% (N-MP) and 24% (DMSO). The use of the most selective agent reduces the energy consumption of this column: the reboiler load is maximal in the case of EG, in comparison with which the load is 47% lower in the case of N-MP and 76% lower in the case of DMSO.

scholarly journals High-Throughput Computational Screening of Ionic Liquids for Butadiene and Butene Separation

Processes ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 165
Author(s):  
Hao Qin ◽  
Zihao Wang ◽  
Zhen Song ◽  
Xiang Zhang ◽  
Teng Zhou
Keyword(s):  
Ionic Liquids ◽  
Energy Consumption ◽  
High Throughput ◽  
Physical Property ◽  
Extractive Distillation ◽  
High Energy ◽  
Molecular Structures ◽  
Boiling Points ◽  
Computational Screening ◽  
Potential Alternative

The separation of 1,3-butadiene (1,3-C4H6) and 1-butene (n-C4H8) is quite challenging due to their close boiling points and similar molecular structures. Extractive distillation (ED) is widely regarded as a promising approach for such a separation task. For ED processes, the selection of suitable entrainer is of central importance. Traditional ED processes using organic solvents suffer from high energy consumption. To tackle this issue, the utilization of ionic liquids (ILs) can serve as a potential alternative. In this work, a high-throughput computational screening of ILs is performed to find proper entrainers, where 36,260 IL candidates comprising of 370 cations and 98 anions are involved. COSMO-RS is employed to calculate the infinite dilution extractive capacity and selectivity of the 36,260 ILs. In doing so, the ILs that satisfy the prespecified thermodynamic criteria and physical property constraints are identified. After the screening, the resulting IL candidates are sent for rigorous process simulation and design. 1,2,3,4,5-pentamethylimidazolium methylcarbonate is found to be the optimal IL solvent. Compared with the benchmark ED process where the organic solvent N-methyl-2-pyrrolidone is adopted, the energy consumption is reduced by 26%. As a result, this work offers a new IL-based ED process for efficient 1,3-C4H6 production.

scholarly journals Comparison of extractive distillation flowsheets for methanol–tetrahydrofuran–water mixtures

2020 ◽  
Vol 15 (3) ◽  
pp. 21-30
Author(s):  
V. M. Raeva ◽  
A. M. Dubrovsky
Keyword(s):  
Energy Consumption ◽  
Software Package ◽  
Extractive Distillation ◽  
Ternary Mixtures ◽  
Extractive Agent ◽  
Water Separation ◽  
Distillation Columns ◽  
Distillation Flowsheets ◽  
Pharmaceutical Industries ◽  
Vapor Liquid

Objectives. Synthesis and comparative analysis of the extractive distillation flowsheets for aqueous mixtures of solvents utilized in pharmaceutical industries using the example of a methanol−tetrahydrofuran−water system with various compositions. The ternary system contains two minimally boiling azeotropes that exist in a vapor–liquid phase equilibrium. To evaluate the selective effect of glycerol, the phase equilibria of the methanol–tetrahydrofuran–water and methanol–tetrahydrofuran–water–glycerol systems at 101.32 kPa were studied.Methods. The calculations were carried out in the Aspen Plus V.9.0 software package. The vapor–liquid equilibria were simulated using the non-random two-liquid (NRTL) equation with the binary interaction parameters of the software package database. To account for the non-ideal behavior of the vapor phase, the Redlich–Kwong equation of state was used. The calculations of the extractive distillation schemes were carried out at 101.32 kPa.Results. The conceptual flowsheets of extractive distillation are proposed. The flowsheets consist of three (schemes I–III) or four (scheme IV) distillation columns operating at atmospheric pressure. In schemes I and II, the extractive distillation of the mixtures is carried out with tetrahydrofuran isolation occurring in the distillate stream. Further separation in the schemes differs in the order of glycerol isolation: in the third column for scheme I (traditional extractive distillation complex) or in the second column for scheme II (two-column extractive distillation complex + methanol/water separation column). Sсheme III caters to the complete dehydration of the basic ternary mixtures, followed by the extractive distillation of the azeotropic methanol–tetrahydrofuran system, also with glycerol. Sсheme IV includes a preconcentration column (for the partial removal of water) and a traditional extractive distillation complex.Conclusions. According to the criterion of least energy consumption for separation (the total load of the reboilers of distillation columns), sсheme I (a traditional complex of extractive distillation) is recommended. Additionally, the energy expended for the separation of the basic equimolar mixture using glycerol as the extractive agent was compared with that expended using another selective agent: 1,2-ethanediol. Glycerol is an effective extractive agent because it reduces energy consumption, in comparison with 1,2-ethanediol, by more than 5%.

Effect of Solvent Content on the Separation and the Energy Consumption of Extractive Distillation Columns

2014 ◽  
Vol 202 (9) ◽  
pp. 1191-1199 ◽  
Author(s):  
Marcella Feitosa De Figueiredo ◽  
Karoline Dantas Brito ◽  
Wagner Brandão Ramos ◽  
Luís Gonzaga Sales Vasconcelos ◽  
Romildo Pereira Brito
Keyword(s):  
Energy Consumption ◽  
Extractive Distillation ◽  
Distillation Columns ◽  
Solvent Content ◽  
Effect Of Solvent

scholarly journals Systematic design of separation process for bioethanol production from corn stover

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Suksun Amornraksa ◽  
Ittipat Subsaipin ◽  
Lida Simasatitkul ◽  
Suttichai Assabumrungrat
Keyword(s):  
Energy Consumption ◽  
Corn Stover ◽  
Process Design ◽  
Extractive Distillation ◽  
Separation Process ◽  
Production Costs ◽  
Bioethanol Production ◽  
Systematic Design ◽  
Separation Processes ◽  
Process Economics

Abstract Separation process is very crucial in bioethanol production as it consumes the highest energy in the process. Unlike other works, this research systematically designed a suitable separation process for bioethanol production from corn stover by using thermodynamic insight. Two separation processes, i.e., extractive distillation (case 2) and pervaporation (case 3), were developed and compared with conventional molecular sieve (case 1). Process design and simulation were done by using Aspen Plus program. The process evaluation was done not only in terms of energy consumption and process economics but also in terms of environmental impacts. It was revealed that pervaporation is the best process in all aspects. Its energy consumption and carbon footprint are 60.8 and 68.34% lower than case 1, respectively. Its capital and production costs are also the lowest, 37.0 and 9.88% lower than case 1.

Benzene purification from thiophene using dimethylformamide as an entrainer in thermally coupled extractive distillation columns

2019 ◽  
Vol 146 ◽  
pp. 391-403 ◽  
Author(s):  
Elena A. Anokhina ◽  
Andrey V. Timoshenko ◽  
Alexander Yu. Akishin ◽  
Anna V. Remizova
Keyword(s):  
Extractive Distillation ◽  
Distillation Columns

Optimal fuzzy control to reduce energy consumption in distillation columns

2005 ◽  
Vol 66 (2) ◽  
pp. 200-208 ◽  
Author(s):  
C. Bouyahiaoui ◽  
L. I. Grigoriev ◽  
F. Laaouad ◽  
A. Khelassi
Keyword(s):  
Energy Consumption ◽  
Fuzzy Control ◽  
Distillation Columns ◽  
Reduce Energy Consumption

scholarly journals Comparative Study of Fluid Package on Extractive Distillation of Ethanol-water Mixture Using Pure Glycerol and Ethylene Glycol as Extracting Solvents

2018 ◽  
pp. 1-12
Author(s):  
O. J. Odejobi ◽  
O. R. Oladokun ◽  
F. J. Ajeigbe
Keyword(s):  
Ethylene Glycol ◽  
Comparative Study ◽  
Feed Rate ◽  
Extractive Distillation ◽  
Base Case ◽  
Water Mixture ◽  
Pure Glycerol ◽  
The Comparative Study ◽  
Separating Agents ◽  
Alternative Designs

The comparative study of Peng Robinson Strygek Vera (PRSV) and Non-Random Two Liquid (NRTL) fluid packages on the extractive distillation of ethanol-water mixture was done using pure glycerol and ethylene glycol as extracting agents. The process was simulated using HYSYS V. 8.4. Pure glycerol and ethylene glycol-glycerol mixture were used as separating agents. The results showed the highest molar composition of ethanol in the distillate at the solvent feed rate of 80 kmol/hr when pure glycerol was used with NRTL fluid package. With the PRSV fluid package the highest ethanol in the distillate was obtained at pure glycerol feed rate of 50 kmol/hr. The ethanol fraction in the distillate was decreasing with increasing ethylene glycol and decreasing glycerol in the ethylene glycol-glycerol mixture. The comparative study of the base case and alternative designs showed high ethanol composition in distillate in the range of 99.46 - 99.96% and 99.96 - 99.67% for NRTL and PRSV fluid package, respectively. It was concluded from the study that the PRSV fluid package could save cost of operation because of lower solvent requirement and energy consumption in the reboiler for both the base case and alternative designs.

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