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Hydrogen is a key raw material for many chemical processes and a clean fuel for various power generation strategies. Coal-to-hydrogen (CTH) conversion is an alternative way to produce hydrogen that is applicable to the abundant coal reserves in China. The use of fossil energy has contributed to severe environmental problems, which drives the development of potential hydrogen production processes. Biomass is a promising renewable energy as well as an attractive resource for producing hydrogen, and it may address some of these environmental problems. In this paper, the simulation results of the biomass-to-hydrogen (BTH) and CTH processes were validated using available experimental data from the literature. Based on the simulation results, a techno-economic analysis was conducted from the viewpoints of the first and second laws of thermodynamics. The techno-economic analysis included determination of the energy efficiency, material consumption, total capital investment, production cost and carbon tax. The energy efficiencies of BTH and CTH were 37.88% and 37.82%, respectively. The BTH process had a larger raw material consumption and total capital investment (TCI) than the CTH process. However, the BTH process had a lower production cost and GHG emissions than the CTH process. The results of energy analyses of the BTH and CTH processes showed that the energy efficiency can be improved from a thermodynamic perspective. The combination of thermodynamic analysis and techno-economic performance evaluation provides insights into the improvement and operation of clean hydrogen production. • Biomass-to-hydrogen (BTH) shows better performances on production cost. • Coal-to-hydrogen (CTH) shows better performances on raw material consumption and TCI. • Techno-economic performance of CTH and BTH is conducted and compared. • BTH has a superior performance in terms of its resistance to price risk than CTH process. [ABSTRACT FROM AUTHOR]

• The proposed control structure can achieve effective control and product yield. • Energy and exergy analysis are implemented to determine the passages of exergy loss. • Reactor operating conditions are optimized by sensitivity analysis. • The maximum C 6 H 11 NO yield is 99.86% and the minimum TAC is 5.988 × 107 $ per year. Cyclohexanone ammoximation is widely used as an efficient method to synthesize cyclohexanone oxime in industrial production. In this study, the cyclohexanone ammoximation production process was explored based on reaction kinetics in order to reduce its energy consumption and total annual cost. The effects of the reaction temperature, space time, and raw material ratios on the cyclohexanone oxime yield were analyzed. Under the optimized operating conditions, the maximum C 6 H 11 NO yield was 99.86%, and the minimum total annual cost was 5.988 × 107 $ per year. Dynamic control of the cyclohexanone ammoximation production process was further explored under the optimized conditions. The proposed control structure could achieve effective control and maintain the desired product yield when flow rate and composition disturbances were introduced. The energy and exergy analyses of the cyclohexanone ammoximation process show that its energy efficiency can be improved from a thermodynamic perspective. The combination of a steady state simulation and dynamic control, thermodynamic analysis, and economic performance evaluation provide insight into the improvement and operation of the cyclohexanone oxime production process. [ABSTRACT FROM AUTHOR]

Using new green solvents to effectively capture volatile organic compounds (VOCs) is considered as an attractive green sustainable chemical development route. In this work, benzene, toluene, ethylbenzene and p-xylene (BTEX) were selected as typical aromatic VOCs. The gas absorption performance of proton [MIM][NTF 2 ] and aprotic [EMIM][NTF 2 ] ionic liquids (ILs) for BTEX were studied by computational thermodynamics combined with gas absorption experiments. Absorption experiments of BTEX and regeneration experiments of ILs were carried out at different temperatures, and ILs had good stability. The interaction type and intensity were determined by Interaction Region Indicator (IRI) analysis of IL-BTEX blend systems. The C-H···π and π-π interaction between imidazole ring and BTEX were the direct reason why ILs can efficiently absorb BTEX. Molecular dynamics simulations were performed to explore the diffusion behavior of gas in ILs. The increase of methyl group increases the interaction strength of the system, and the fractional free volume of IL-BTEX blend systems decreases gradually, which limits the diffusion of BTEX. Non-bond interaction analysis shows that van der Waals interaction was the main driving force of BTEX absorption in ILs. • Protic [MIM][NTF 2 ] and aprotic [EMIM][NTF 2 ] ILs were proposed to enhance the capture of BTEX. • PIL and AIL still maintained good absorption effect after 5 adsorption-desorption cycles. • The C-H···π and π-π interaction is the main interaction between ILs and BTEX. • The diffusion behavior of gas in ILs was revealed by MD simulations and FFV theory. • van der Waals interaction is the main driving force of BTEX absorption in ILs. [ABSTRACT FROM AUTHOR]

Biogas, as a cheap and easily available clean biomass energy, has attracted extensive attention. In this work, the simultaneous decarburization, desulfurization and dehydration of biogas with ionic liquids (ILs) was proposed. Based on the COSMO-RS model, the separation performance of 400 ILs composed of 20 cations and 20 anions was screened by using Henry's law constant (HLC) and selectivity coefficient as separation performance indexes. Among them, 1,3-dimethylimidazolium methylsulfate [C 1 MIM][MeSO 4 ] was considered to be the most promising candidate absorbent. Furthermore, the HLC and selectivity of CH 4 , CO 2 and H 2 S in [C 1 MIM][MeSO 4 ] were predicted by COSMO-RS at different temperatures and pressures. The results show that the selected [C 1 MIM][MeSO 4 ] has excellent selective absorption performance for CO 2 and H 2 S. The regeneration experiment of [C 1 MIM][MeSO 4 ] showed that the absorption effect of CH 4 , CO 2 and H 2 S was almost unchanged (i.e., HLC was almost unchanged) after 6 absorption-desorption cycles. Molecular surface electrostatic potential (ESP) analysis was performed to obtain the binding sites of intermolecular interactions to reveal the separation mechanism of simultaneous decarbonization, desulfurization and dehydration of ILs. Interaction region indicator (IRI) analysis showed that IL [C 1 MIM][MeSO 4 ] mainly interacted with the components to be separated in the form of hydrogen bonds. The spatial distribution function (SDF) reveals the spatial distribution of different gases around [C 1 MIM][MeSO 4 ] from the perspective of cluster macromolecules. This provides theoretical insights into molecular thermodynamics and dynamics for the development of new ILs for biogas purification. • Simultaneous decarburization, desulfurization and dehydration of biogas with ILs was proposed. • COSMO-RS model was implemented to screen 400 kinds of ionic liquids for biogas absorption. • The CO 2 , CH 4 and H 2 S have lower Henry's law constant and higher selectivity in [C 1 MIM][MeSO 4 ]. • The absorption mechanism by the [C 1 MIM][MeSO 4 ] has been revealed by QC calculation and MD simulation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Diesel model consisted of 1-methylnaphthalene, n-hexadecane and 1-tetradecene. • IL [EMIM][NTF 2 ] shows higher selectivity among the selected extractants. • Thermodynamic consistency test shows that LLE data obtained from the experiment is reliable. • The essence and discipline of weak interactions between extractants and aromatics/aliphatic hydrocarbons was probed. The high content of aromatics in fluid catalytic cracking (FCC) diesel, especially bicyclic aromatics, seriously hindered the quality upgrading of FCC diesel. Liquid-Liquid extraction is an effectively method to reduce the content of aromatics in FCC diesel and improve oil quality. In this work, [EMIM][NTF 2 ] (1-Ethyl-3-methylimidazolium Bis(trifluoromethylsulfony)imide) was selected as the most appropriate extractant from 44 ILs candidates, the common organic solvents (i.e., sulfolane (SUF), 1-Methyl-2-pyrrolidinone (NMP)) and [EMIM][NTF 2 ] were used to separate 1-Methylnaphthalene from the model oil of 1-Tetradecene + n-Hexadecane + 1-Methylnaphthalene mixtures. The quaternary liquid–liquid equilibrium experiment was carried out at 303.15 K, and the results indicate that IL [EMIM][NTF 2 ] show the higher selectivity than the common solvents. After recycling for 6 times, the extraction efficiency of [EMIM][NTF 2 ] has hardly decreased. Quantum chemical (QC) calculation were performed to study the interaction mechanism between three different extractants and mixtures at the molecular level. Molecular polarity index (MPI) analysis indicated that 1-Methylnaphthalene was more soluble in extractants because its MPI values was closer to that of the extractants. The common results of energy decomposed, independent gradient model and atoms in molecules analysis showed that the interaction energy between 1-Methylnaphthalene and extractants is dominated by weak hydrogen bond and dispersion (e.g., van der Waals). Compared to aliphatic hydrocarbons (i.e. 1-Hetradecene and n-Texadecane), the interaction energy between extractants and 1-Methylnaphthalene systems are larger because of the existence of C-H⋅⋅⋅π and hydrogen bond interaction. [ABSTRACT FROM AUTHOR]

Owing to the negative environmental impact and safety problems of fossil fuel resources, chemical processes based on renewable energy have been extensively studied for further development. In this study, the thermodynamic, economic, and environmental performances of biomass-to-hydrogen (BTH) conversion were assessed using corn straw as a raw material. Further, the process used to achieve BTH conversion with/without carbon capture and storage (CCS) was evaluated and analyzed in this study. According to the simulation results, the economic and environmental properties of BTH processes using different CO 2 capture rates were evaluated via thermodynamics and life cycle assessment. Compared with the biomass hydrogen production process without CCS, the EC of the BTH process with CCS decreased by 17%. However, the total investment and production cost of biomass hydrogen production with CCS increased by 1.3% and 14.6–19.4%, respectively. The energy efficiency of BTH conversion with CCS was 17% lower than that of BTH conversion without CCS. Further, the payback period of the BTH process performed with CCS was approximately 5–6 years. According to the energy consumption and the economic and environmental performances, BTH conversion with a CO 2 capture rate of 80% is a appropriate CCS system for CO 2 capture. The life cycle assessment of BTH conversion demonstrates that the BTH system with CCS can result in negative greenhouse gas emissions. The development of the BTH process using CCS is thus of great significance for achieving carbon neutralization. [Display omitted] • Cradle-to-grave life cycle analysis is carried out for BTH with or without CCS. • Techno-economic performances of the BTH processes with different carbon capture rates are compared. • BTH process with CCS can realize negative emissions of greenhouse gases. • BTH with a carbon capture rate of 80% is a more appropriate CCS system for CO 2 capture. [ABSTRACT FROM AUTHOR]

To further reduce the energy consumption, investment and operation cost of the distillation process, DWC-B and FTCDC are used to strengthen the separation process of ibuprofen sodium mother liquor. Based on the process simulation results, thermodynamic efficiency, economic and environmental impact assessment were carried out and compared with the benchmarked CTCD process. DWC-B and FTCDC have obvious advantages in economy, energy saving and environmental impact. Compared with the benchmarked CTCD process, the FTCDC process is more attractive economically, and its total annual cost is reduced by about 7.83%. The thermodynamic efficiency of DWC-B is 17.62%, and the CO 2 emission is reduced by 11.39%. Compared with the benchmarked CTCD process, DWC-B and FTCDC have the advantages of high thermodynamic efficiency, low economic cost and low CO 2 emission with a great industrial application prospect. [Display omitted] • DWC-B and FTCDC have significant advantages in reducing energy consumption and saving TAC. • The FTCDC was more attractive on TAC saving with the value of 7.81%. • The thermodynamic efficiency of DWC-B is 17.62% and the CO 2 emissions is reduced by 11.39%. [ABSTRACT FROM AUTHOR]

An assessment method that combines thermodynamic, techno-economic, and life cycle environmental analyses was applied to estimate the theoretical production of ketone ammoximation. Based on the reaction kinetics of ketone ammoximation, the effects of operating conditions on the conversion and selectivity were explored. The maximum acetone conversion and acetone oxime selectivity were 95% and 98%, respectively. The total annual cost was 1.29 × 107 $/year. The exergy efficiency was found to be more than 19.9%. The product-refining unit was considered as the unit with the largest exergy loss contribution, and the exergy loss rate was 68.5%. The thermodynamic analysis of the acetone oxime production process showed that its exergy loss could be reduced. The environmental performance of the acetone ammoximation process was determined by life cycle analysis. The results of environmental indicators showed that the GWP, AP, and ODP of the ketone ammoximation are 84815.4 kg·eq. CO 2 , 91.58 kg·eq. SO 2 , and 1.6 × 10−10 kg·eq. R11, respectively. This combination of life cycle environment, thermodynamic and techno-economic evaluation provides a basis for the improvement and sustainable development of the production process of ketoxime. • GWP as the main index of life cycle analysis, the result is 84815.4 kg·eq. CO 2. • Product refining unit is the main contribution unit of exergy damage and exergy loss rate is 68.5%. • The maximum DMKO conversion and selectivity are 95% and 98%, and the minimum TAC is 1.29 × 107 $/year. [ABSTRACT FROM AUTHOR]

Methanol is an important basic industrial chemical. At present, coal-to-methanol (CTM) production is the main mode of production used in China, but the mining of coal has almost irreversible environmental impacts. Thus, producing methanol by replacing coal with abundant biomass resources has been identified as a promising alternative approach. Before large-scale application, it is necessary to study the environmental impacts and energy consumption of biomass-to-methanol (BTM) methods to evaluate their capacity to replace CTM production. In this work, CTM and BTM processes are modeled and simulated. Life cycle energy consumption, global warming potential, acidification potential and human toxicity potential are studied for the two processes from a life cycle assessment perspective. The results show that methanol synthesis and purification units constitute the most energy intensive facets of methanol production. Under the same production capacity, the life cycle energy consumption of BTM processes is lower than that of CTM processes and offers great advantages in terms of environmental impacts, especially in reducing greenhouse gas emissions. A sensitivity analysis identifies pipeline transport as an energy efficient and clean mode of long-distance methanol transport. From comparative results, using biomass resources instead of coal to produce methanol is identified as a feasible alternative. • A comparative life cycle assessment of CTM process and BTM process. • The subunits of methanol production are analyzed from the perspective of life cycle assessment. • Sensitivity analysis is used to evaluate the mode of methanol transportation. • BTM process has high GHG abatement potential. [ABSTRACT FROM AUTHOR]

In this study, the techno-economic, energy consumption (EC), and environmental performances of biomass-to-hydrogen (BTH) production with/without methane tri-reforming (MTR) from corn straw were studied. The techno-economic analysis includes an assessment of the energy efficiency, MTR operating conditions, total capital investment (TCI), production cost (PC), and payback period. The BTH energy efficiency with MTR is 17.08% higher than that without MTR. The Claus unit is the largest contribution unit of energy loss. The reaction temperature and operating pressure of one MTR unit are 800 °C and 0.1 MPa, respectively. Compared with BTH without MTR, the TCI of BTH with MTR increased by 10.97%, and the PC decreased by 10.12%. The static payback period of BTH with MTR is approximately 4.72 yr. BTH without MTR exhibits 3.09% less EC and 7.85% greenhouse gas emissions than that of BTH with MTR. The life cycle analysis of the BTH process illustrates that the BTH with MTR can realize negative carbon dioxide (CO 2) emissions when considering the natural carbon cycle. The evaluation method combines a thermodynamic analysis with a life cycle assessment, which is significant for the development of clean hydrogen production technology with low carbon and high energy savings. • Cradle-to-grave life cycle analysis is carried out to BTH with/without MTR process. • Techno-economic performance of BTH with/without MTR process is compared. • BTH with MTR process can realize negative emission of greenhouse gases. • The MTR unit realizes internal self-heating and reduces energy consumption. [ABSTRACT FROM AUTHOR]

• The influence of methyl group in amide extractants on olefin extraction was studied by LLE and quantum chemical calculations. • The olefin selectivity is determined by the difference in electrostatic interaction. • Dispersive and electrostatic interactions both contribute to the olefin distribution coefficients. • The amount and intensity of C-H⋯O interactions and N/C-H⋯π interactions are all affected by methyl groups in extractants. • The existence of the C–H⋯O and N–H⋯π interactions were verified by the infrared spectroscopy. In this work, the influence mechanism of methyl group in the structure of amide solvent on the extraction and separation of alkene (1-hexene or 1-octene) from n-heptane has been studied by a combination of liquid–liquid equilibrium (LLE) experiments and quantum chemical calculations. For LLE experiments, as the number of methyl groups in the extractant structure increases, its selectivity for alkene (1-hexene or 1-octene) gradually decreases, and the distribution coefficients of alkene (1-hexene or 1-octene) and n-heptane gradually increase. In the interaction between 1-hexene and extractant, the amount and intensity of C-H⋯O interactions, as well as the presence or absence of N/C-H⋯π interactions and their intensities, are all affected by the amount (0,1,2,3) of methyl group introduced into the amide solvent. The existence of the C-H⋯O and N-H⋯π interactions were verified by the infrared spectroscopy. With increasing methyl group amounts in the extractant structure, the dispersion interaction strengthens, while the contribution percentage of electrostatic interaction and Δ E elst /Δ E declines, leading to the increase of distribution coefficient and decrease of selectivity for alkene (1-hexene or 1-octene) respectively. [ABSTRACT FROM AUTHOR]

Developing coal-to-hydrogen (CTH) process is a major way to relieve the conflict between hydrogen supply and demand. The environmental problems caused by the utilization of fossil energy have driven the progress of alternative hydrogen production processes. Biomass energy, as an attractive renewable hydrogen resource, can solve some environmental problems. In this study, CTH and biomass-to-hydrogen (BTH) processes are modeled and studied. Based on the simulation results, the life cycle analysis energy consumption (EC) and greenhouse gas (GHG) emissions of CTH and BTH processes are performed. The system life cycle boundary includes raw material production (or collection); transportation; synthesis gas generation; hydrogen purification; hydrogen transportation and application. The results show that the EC of the BTH process is 75.4% lower than the corresponding value of CTH process. GHG emissions of BTH process are 89.6% lower than corresponding values of CTH process. In addition, sensitivity analysis shows that pipeline transport is the most environmentally friendly transport mode. Gasification temperature is in the range of 1400–1500 °C, the system achieves the highest energy efficiency and the lowest GHG emissions. Suggestions were proposed for the policy formulation of the sustainable development of the hydrogen industry, which is of great significance to reduce GHG emissions and improve energy efficiency. • Cradle-to-grave life cycle analysis is carried out to the CTH and BTH processes. • The optimal gasification temperature and hydrogen transport model are obtained. • Compared with CTH, BTH shows better performances on life cycle EC and GHG emissions. • Lower LCEs demonstrate the promising of the BTH process. • Suggestions are given to reduce energy consumption and environmental impact. [ABSTRACT FROM AUTHOR]

A correlation model was explored and established for the first time, linking the properties of entrainers to the process economics of extractive distillation separation for ternary azeotropes. Firstly, the extraction process of ternary azeotrope (methyl tert-butyl ether/ethanol (EtOH)/water) with common entrainers was optimized using a multi-objective optimization method based on a genetic algorithm. The optimal process parameters were obtained, and dimethyl sulfolone emerged as the best entrainer for the system. An economic correlation model was developed using machine learning to link the properties of entrainers and total annual cost (TAC). The model exhibited a determination coefficient of 0.993 and a single percentage error of less than 2% for each data set, indicating a significant fitting degree and prediction accuracy. The feasibility of selecting the optimal entrainer and calculating the economic benefit of the model was verified through another ternary azeotrope system (i.e., tetrahydrofuran/EtOH/water). The model provides valuable insights into energy savings and entrainer screening in extractive distillation. Additionally, the influence of the heat integration process with different entrainers on the economic benefit was analyzed, and the optimum entrainer changed to glycerol after the heat integration process. This finding suggests that determining the optimum entrainer should consider the possible heat integration process design. Finally, the relationship between the intermolecular interaction mechanism and separation effect was revealed through quantum chemical calculations. [ABSTRACT FROM AUTHOR]

• A control test was carried out based on the prediction results of COSMO-RS model. • Extraction efficiency of TP and BTP by TEAC:PrA were 98.06 % and 98.53 %, respectively. • The structure–activity relationship between DES and TP or BTP was studied by molecular simulation. • The interaction types and site distribution of extractive desulphurization were revealed at the atomic level. The improvement of fuel quality requires the reduction of sulfur content. The main challenge of catalytic cracking diesel extraction desulfurization is to find low-price and good-performance extractants. Based on experimental research, this work further explores the separation mechanism of DES for thiophene (TP) and benzothiophene (BTP). First, the COSMOS-RS model was used to predict the separation performance of 10 HBAs and 10 HBDs for TP and BTP. The results showed that the low-cost carboxylic acid based DES had excellent separation performance. Secondly, the effect of experimental conditions on the separation performance of three carboxylic acid based DESs was investigated. When the molar ratio of DES to TP and BTP was 3:1, after three stage extraction, the extraction rates of TP and BTP by TEAC: PrA(1:3) were 98.06 % and 98.53 %, respectively. Finally, the structure–activity relationship was studied by using quantum chemistry and molecular dynamics simulation. It was found that E vdW plays a dominant role in the desulfurization process and does not include H-bond interactions. TEA+ was distributed parallel to the aromatic ring and has a CH···π interaction with thiophene. TP and BTP were distributed in the voids of DES and do not affect the regeneration performance of DES. [ABSTRACT FROM AUTHOR]

To efficiently recover dipropyl ether/isopropanol from wastewater, realizing resource recycling and clean production, a viable solution for extractive distillation with mixed solvent (Glycerin: [EMIM][SCN] = 0.254: 0.746) was proposed. Quantitative and qualitative methods were used to screen solvents. Based on COSMO-RS, the selectivity of species in 352 ILs was calculated. The interaction relationship between the microscopic molecular structure and separation performance was researched, and the process mechanism of solvents separating the ether-containing ternary azeotropes was revealed. The use of genetic algorithms for multi-objective optimization determined the splendid process parameters. The scheme was evaluated in terms of economic benefits, environmental impact, and exergy losses. Compared with the pressure swing extractive distillation of a single solvent, the total annual cost and gas emission of the technology using mixed entrainers decreased sharply. Combined with Heat-integrated can realize the low-cost recovery of dipropyl ether/isopropanol from wastewater, which has a guiding role in the industrial separation of ternary azeotrope. • Separation dipropyl ether/isopropanol from wastewater used mixed entrainer based on ionic liquids. • Quantitative and qualitative methods were used to screen ionic liquids and organic entrainers. • Revealed the separation mechanism of ether containing ternary azeotropes. • The scheme was evaluated in terms of multiple performance. • Researched process intensification to save energy and reduce consumption. [ABSTRACT FROM AUTHOR]

• An innovative technique for efficiently treating pyridine and phenol in coal gasification wastewater has been proposed. • The optimal entrainer was determined from various angles using VLE, COSMO-SAC and quantum chemical calculations. • The relationship between separation sequence and energy consumption is explored. • The HI-DWC-EPSDP-SE process demonstrates optimal economic, environmental, and thermodynamic efficiency performance. The phenol and pyridine of coal gasification wastewater (CGW) are extremely toxic pollutants. Thus, there is an urgent need to develop a new process for the effective treatment of phenol and pyridine in CGW. Vapor-liquid equilibrium (VLE) and COSMO-SAC model analysis were used to select the entrainer, and interaction region indicator analysis was applied to elucidate the separation mechanism. Aiming to minimize total annual cost (TAC), the optimal process parameters were established through a sequential iterative procedure; extractive pressure-swing distillation process: separation sequence E (EPSDP-SE) process exhibiting the best performance. Heat integrated extractive pressure-swing distillation with dividing wall column process: separation sequence E (HI-DWC-EPSDP-SE) was developed by integrating a thermal process and dividing wall distillation technology. In comparison to EPSDP-SE, HI-DWC-EPSDP-SE achieved reductions of 26.97% in TAC, 38.89% in total operation cost, and 6.21% in total capital cost. Additionally, it lowered total acid gas emissions and energy consumption by 39.98% and enhanced thermodynamic efficiency by 54.72%. The HI-DWC-EPSDP-SE process showcases exceptional separation performance in terms of economy, energy consumption, and environmental impact. [ABSTRACT FROM AUTHOR]

• The first time to explore the effect of ILs and DESs in separating diisopropyl ether-ethanol azeotrope system. • Combined with molecular simulation, the mechanism of extraction and separation was clarified. • Designed the extraction and separation process of diisopropyl ether-ethanol-ILs for the first time. • For the extraction process, the impact on human health and the environment was evaluated using life cycle assessment. • Considering the high cost of ILs, recycling experiments are carried out. Ionic liquids (ILs) and deep eutectic solvents (DESs) were first proposed as green solvents to study and compare their azeotropic separation effects in diisopropyl ether (DIPE) and ethanol (EA). The COSMO-RS model was used to screen ILs/DESs, and the feasibility of the extractants were comprehensively analyzed in terms of viscosity, thermal stability, and toxicity. Experiments were carried out on selected ILs and DESs, and the results showed that the separation effect of ILs was significantly stronger than that of DESs. Quantum chemical calculations and molecular dynamics simulations were combined to comprehensively analyze and compare the microscopic mechanisms of extraction separation. Based on the experimental data, a DIPE-EA extraction-coupled separation process was designed. For the first time, life cycle analysis was used to comprehensively evaluate the impact of this process on human health and the environment from multiple perspectives, providing theoretical guidance for the separation of alcohol ethers in the industry. [ABSTRACT FROM AUTHOR]

A clean and sustainable process for separating n-heptanol/n-hexanol/water industrial mixing system by extractive distillation via mixing organic solvent with ionic liquid as an entrainer was proposed. The mechanism of intermolecular microscopic interaction was explored by quantum chemistry calculation. By using multi-objective optimization, the optimal operating parameters of the process were obtained. In addition, process intensification technology was introduced, which improved the problems of high cost and high energy consumption in the conventional extractive distillation process. Finally, multiple performances were evaluated and analyzed for different processes. It was found that the coupled heat integration and heat pump technology to assist the extractive distillation process saved 10.45% in terms of economy, reduced gas emissions by 49.00%, and reduced energy consumption by 48.99% compared to the basic extractive distillation process. This confirmed the reliability and feasibility of implementing the process intensification technology. This work demonstrates the application of organic solvent mixed with ionic liquid as entrainer and process intensification technology in the extractive distillation process, providing guidance and reference for the design of the extractive distillation process. [ABSTRACT FROM AUTHOR]

• Azeotropic coupling pressure-swing distillation is proposed to separate cresol isomers. • Quantum chemical calculations reveal the rationality of solvent screening. • Heat integration technology is further used to improve the process benefits. In this work, an azeotropic coupling pressure-swing distillation separation technology was proposed for the first time to achieve efficient separation of near-boiling complex separation systems in coal chemical wastewater, namely cresol isomers (m-cresol and p-cresol), and achieves process intensification by introducing heat-integration technology. Vapor-liquid equilibrium data and relative volatility analysis were used to screen suitable entrainer. Quinoline is considered to be the most potential entrainer. Quantum chemical calculations were performed to reveal the separation mechanism of the entrainer and the system to be separated at the molecular scale to demonstrate the feasibility of quinoline as an entrainer for the separation of cresol isomers. Based on the Aspen Plus V11 platform, two processes of APSDP and HI-APSDP were built. HI-APSDP can save 31.31% in TAC, reduce 39.50% in total energy consumption and gas emissions, and increase 26.01% in thermodynamic efficiency compared with APSDP. HI-APSDP process is an economical, energy-saving, and environmentally friendly production scheme superior to the APSDP process, which will have essential development prospects in coal chemical wastewater (cresol isomers) treatment. [ABSTRACT FROM AUTHOR]

Batch operation is commonly used for the Claisen ester condensation reaction, resulting in relatively high energy consumption. For the industrial production of diethyl 2-ethyl-2-phenylmalonate, the key productivity-limiting factor is the Claisen ester condensation reaction via batch operation, which requires ＞ 22 h. In this study, the optimum reaction conditions were determined experimentally and a novel reactor and process to produce diethyl 2-ethyl-2-phenylmalonate are proposed, enabling continuous operation. The time required to produce a single output unit was reduced from 34 h to 5 h, while the process energy consumption was reduced by approximately 80%. All solutions used during the production process can be recycled and modeling and simulation of the process were extensively performed to determine the economic, energy, exergy, and environmental costs of the new process according to the principles of green chemistry. The analysis showed that the exergy loss of separation and purification unit is the largest, accounting for 48.1% of the entire process. The operating cost of the newly developed process with an annual output of 1400 t of product is $1.389 × 107 per year. The consumption per unit of output products was significantly lower than those of existing processes. The environmental emissions of the new production process provide a reliable basis for further optimization. The realization of continuous process operation provides a useful reference for other synthetic reactions currently achieved using batch reactors. Image 1 • The optimum reaction conditions are optimized by experiment. • A continuous production process of diethyl 2-ethyl-2-phenylmalonate is proposed. • The time required of producing per unit output product is reduced from 34 h to 5 h. • The process energy consumption is reduced by about 80%. • Exergy, energy, economic and environmental analyses of the new process are studied. [ABSTRACT FROM AUTHOR]

• The application of DESs in MTBE production is proposed for the first. • An extraction coupled distillation process based on DESs was developed. • The separation mechanism of DESs was elucidated at molecular scale. • DESs was determined by quantum chemistry and molecular dynamics simulation. Deep eutectic solvents (DESs) were first applied in the azeotrope separation process for the production of methyl tert -butyl ether (MTBE). Quantum chemistry and molecular dynamics simulations were used to explore the interaction mechanism of ChCl-based DESs in the liquid–liquid extraction of the MTBE–methanol (MeOH) system. The results showed that the extraction of MeOH by DESs mainly depended on the Van der Waals interactions between Cl atoms in ChCl and H atoms in the MeOH hydroxyl group. Hydrogen bond donors also enhanced the extraction effect to a certain extent. Liquid-liquid equilibrium experiments were carried out for the three selected DESs, and the ideal separation effect was obtained. The complete separation process of the MTBE-MeOH system was developed based on experimental data. This work demonstrates the application of DESs in the MTBE-MEOH system and provides guidance for the selecting and analysis of other DES extractants for the separation of low-carbon alcohol systems. [ABSTRACT FROM AUTHOR]

• Reactive with partial reflux and extractive distillation using ionic liquid-base mixed solvent combined with dividing wall column is a beneficial energy-saving strategy. • REDWC with partial reflux ionic liquid-base mixed solvent could achieve 28.38% TAC savings. • REDWC with partial reflux using ionic liquid mixed solvent could energy-saving 28.81%. The "double carbon" goal puts forward new requirements for the low-carbon development of industrial parks. This work focuses on the process intensification by the combination of reactive and extractive distillation (RED) with ionic liquids-based mixed solvents (ILMS) for ester hydrolysis to alcohol process to improve the distillation process performance. The relative volatility is used as an indicator for the screening of traditional organic solvents. Based on solubility and selectivity, COSMO-RS model is performed for the screening of ionic liquid entrainers. The process performances were compared with the benchmarked RED using dimethyl sulfoxide as entrainer process according to simulation results. RED with partial reflux using ILMS process could reduce energy consumption and TAC by 26.44% and 24.66%, respectively. Further, the combination of reactive distillation column with partial reflux and dividing wall column extractive distillation process (REDWC) using ILMS can reduce energy consumption and TAC by 28.81% and 28.38%, respectively. Compared with the benchmark process, the novel RDWCED process has excellent energy, economic and environmental performance, and has broad industrial application prospects. [ABSTRACT FROM AUTHOR]

[Display omitted] • The IL ([EMIM][DEP]) can efficiently capture the higher alcohols from CO 2 gas mixture; • Interaction mechanisms were identified at the molecular level; • The relationship between VLE behaviors and HB interactions was explored; • Capturing higher alcohols from CO 2 gas with ILs is a process intensification technology. Ionic liquids (ILs) as green solvents were first proposed to capture low-carbon alcohols (e.g., methanol, ethanol and 1-propanol) from the syngas tail gas. The vapor–liquid equilibrium (VLE) data for the binary mixtures of low-carbon alcohols with 1-ethyl-3-methyl-imidazolium diethyl phosphate ([EMIM][DEP]) were experimentally measured. The UNIFAC-Lei model demonstrated the best performance in predicting VLE data among all the investigated predictive molecular thermodynamic models. However, the COSMO-SAC-UNIFAC model could reproduce the low-carbon alcohols gas absorption characteristics without any experimental data input, and was more accurate than the original UNIFAC and COSMO-SAC models in this case. Using quantum chemistry calculations and wave function analysis, the separation mechanism was revealed on a molecular level. The relationship between thermodynamic behaviors and hydrogen bond interactions in CO 2 –low-carbon alcohols–[EMIM][DEP] systems was systematically explored. Additionally, theoretical guidance for the design and screening of task-specific ILs in condensable gas separation processes was provided. [ABSTRACT FROM AUTHOR]