Fluid Phase Equilibria最新文献_第4页

A robust setup for efficient characterization of multicomponent vapor-liquid equilibria using Raman spectroscopy

IF 2.8 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-01-19 DOI: 10.1016/j.fluid.2025.114344

Marvin Kasterke, Leo Bahr, Hans-Jürgen Koß, Thorsten Brands

Vapor-liquid equilibrium (VLE), a crucial thermodynamic property in diverse industrial processes, assumes paramount significance in the development, optimization, and operation of separation processes and various applications. Despite their central role, large sample volumes, long measurement times and the handling of the apparatus are a challenge for the precise determination of VLE data. In response to these challenges, we present an innovative Raman spectroscopy-based measurement setup that enables fast, accurate and user-friendly characterization of VLE. The application of Raman spectroscopy enables non-invasive analysis of vapor and liquid-phases in small sample volumes (<3 ml) for multiple VLE data points. The usage of a compact isothermal VLE measurement cell ensures rapid and reliable VLE control. The combination of the equilibrium cell with a highly confocal fiber-coupled Raman probe in backscattering configuration and a high-throughput spectrometer establishes an efficient setup for quantifying VLE data in a broad range of conditions. The setup has been validated for vapor pressure curves of methyl tert‑butyl ether (MTBE), isooctane (2,2,4-trimethylpentane) and cyclohexane for a temperature range of 283.15 K to 333.15 K and the measurement of the binary VLE MTBE-isooctane at 318 .15K. the setup allows a highly efficient access to VLE data of industrial relevance.

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引用次数: 0

Measurement for the critical temperatures, pressures, and thermal diffusivities of monoethanolamine, diethanolamine, and 2-amino-2-methyl-1-propanol

IF 2.8 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-01-18 DOI: 10.1016/j.fluid.2025.114343

Nataliya S. Bogatishcheva, Alexander P. Popov, Dmitriy A. Galkin, Eugene D. Nikitin

The critical pressures, critical temperatures, and thermal diffusivities have been measured for monoethanolamine (MEA), diethanolamine (DEA), and 2-amino-2-methyl-1-propanol (AMP). These compounds are the components of mixtures used for the capture of various greenhouse gases, mainly CO₂. The pulse-heating method applicable to highly thermally unstable compounds has been used to measure the critical properties. The combined relative expanded uncertainties at 0.95 level of confidence are 0.015 for the critical temperatures and from 0.036 to 0.047 for the critical pressures. The acentric factors of the alkanolamines under study have been calculated. The critical properties of the alkanolamines measured in this work have been compared with the literature data as well as with the values estimated by the group contribution methods of Wilson and Jasperson, Nannoolal et al., and Hukkerikar et al. All the group-contribution methods underestimate both the critical temperatures and pressures of the alkanolamines with one exception: the critical pressure of DEA estimated by the method of Nannoolal et al. is higher than the experimental value. In addition, such a comparison has been made with the critical properties of alkanolamines obtained using three versions of the SAFT equation of state (PρT-SAFT-HR, PC-SAFT, and SAFT-HR). These models of the SAFT EoS overestimate the critical temperature of the MEA and AMP and the critical pressure of the MEA but underestimate the critical pressure of the AMP.

The thermal diffusivities of MEA, DEA and AMP have been measured by the laser flash method using a LFA 457 MicroFlash system (Netzsch, Germany) at atmospheric pressure; the temperature range covered has been from 303.15 to 373.15 K. Linear polynomials have been used to describe the dependences of the thermal diffusivity on temperature. The thermal conductivities of the alkanolamines have been calculated from the experimental data on thermal diffusivity and the literature data on density and heat capacity. The combined relative expanded uncertainties are 0.05 and 0.06 for thermal diffusivity and thermal conductivity, respectively. The equations for calculating the thermal conductivities of MEA, DEA, and AMP have been obtained using the experimental data obtained in this work and taken from the literature. The comparison of the experimental values of thermal conductivity and those calculated by the method of Govender et al. has been performed. The technique of Govender and co-workers significantly overestimates the thermal conductivity of the alkanolamines.

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引用次数: 0

Thermophysical properties and isobaric vapor-liquid equilibria for 3,4-difluoronitrobenzene and 2,5-difluoronitrobenzene

IF 2.8 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-01-17 DOI: 10.1016/j.fluid.2025.114341

Xueqiang Shao , Shucui Han , Lin Lin , Jinyi Chen , Jinbei Yang

3,4-Difluoronitrobenzene and 2,5-difluoronitrobenzene are significant fine chemical intermediates, widely applied in the fields of medicine, pesticides, and liquid crystal materials, particularly in pharmaceutical production. The available literature on their thermodynamic properties is scarce. Thermophysical property measurements for pure 3,4-difluoronitrobenzene and 2,5-difluoronitrobenzene liquids were performed in relation to temperature: density (293.15 to 353.15) K, viscosity (293.15 to 353.15) K, saturated vapor pressure (366 to 478) K. Isobaric vapor-liquid equilibria (VLE) data for the 3,4-difluoronitrobenzene and 2,5-difluoronitrobenzene binary system were experimentally determined at 101.2 kPa. The correspondence between density and temperature was successfully modeled utilizing the DIPPR equation. Meanwhile, viscosity data were analyzed using four selected equations, with VFT equation yielding the most precise results. Furthermore, the correlation between saturated vapor pressure and temperature can be precisely established using Antoine and Riedel equations. The binary VLE data were modeled using NRTL and Wilson equations, yielding binary interaction parameters. These parameter-derived predictions closely aligned with experimental findings, revealing the absence of azeotropic behavior in the binary system. The thermophysical properties of these pure components, along with VLE data provided, are significant for the separation process of 3,4-difluoronitrobenzene and 2,5-difluoronitrobenzene.

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引用次数: 0

Contributions to ionic activity coefficients: A review and comparison of equations of state with molecular simulations

IF 2.8 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-01-16 DOI: 10.1016/j.fluid.2025.114339

Nefeli Novak , Fufang Yang , Martin Due Olsen , Xiaodong Liang , Nicolas von Solms , Ioannis G. Economou , Marcelo Castier , Jean-Charles de Hemptinne , Athanassios Z. Panagiotopoulos , Georgios M. Kontogeorgis

Advanced Equations of State for electrolyte solutions (e-EoS) consist of many contributions stemming from different intermolecular forces, e.g. repulsion, dispersion, hydrogen bonding, as well as ionic interactions between ions, ion solvation and possibly others. It is difficult to establish a priori which is the correct balance of the various contributions, and different parameter estimation strategies may result in similar performance of models having entirely different trends with respect to the contribution of the various terms. The first part of this work is a literature review on the balance of forces exhibited by existing electrolyte models, both activity coefficient models and e-EoS. In the second part of this work, the activity coefficients and the contributions of the various terms calculated by molecular simulation (MS) based on the recent studies by Saravi and Panagiotopoulos are analyzed and compared to their e-EoS counterparts at 25 °C and 1 bar. We have considered three e-EoS from literature, namely the eSAFT-VR Mie, ePPC-SAFT and e-CPA. MS studies have been presented in literature both using the so-called implicit and explicit simulations, but only the latter are considered here where water is treated as a molecule, as these are in closer agreement to experimental data. Although correspondence between MS contributions and e-EoS terms is not fully established, some conclusions related to the performance of e-EoS are obtained.

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引用次数: 0

Prediction of gas hydrates phase equilibrium in porous media – Pore size effect and thermodynamics approach

IF 2.8 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-01-16 DOI: 10.1016/j.fluid.2025.114330

Sara Kishan Roodbari, Vahid Mohebbi, Reza Mosayebi Behbahani

Rapid growth in conventional energy consumption has drawn attention to renewable resources and unconventional fossil energy sources, such as Natural Gas Hydrates (NGHs). Comprehensive knowledge of the NGH accumulation conditions is the basis of exploration and exploitation. The mechanisms and factors, related with sediments and their matrix characteristics, and thermodynamic conditions affect the formation and dissociation of NGHs in sediments. Thermodynamic data on hydrate formation in porous media is limited due to the time-consuming and complex nature of obtaining experimental data. The use of thermodynamic models capable of predicting hydrate formation conditions is highly beneficial for studying gas extraction from hydrate reservoirs. In this research, previously published experimental data and modeling were analyzed. The impact of pore size on the formation of natural gas hydrates (NGHs) was modeled using two different thermodynamic approaches (fugacity and activity models), and their adaptation to experimental data was studied. The outcomes of the thermodynamic models revealed that the fugacity and activity model exhibited overall average absolute percent deviation (AAD%) 2.89 and 4.6 %, respectively. Minimum and maximum percentages of the average absolute deviation (AAD%) in fugacity model at 1.05 % and 5.5 %, respectively. Meanwhile, the activity model showed a minimum deviation of 1.67 % and a maximum deviation of 9.22 %. Additionally, it was observed that as the pore size diameter approaches approximately 100 nm, the equilibrium hydrate pressure in porous media and the equilibrium pressure in pure water become close. The surface tension of 0.039(J/m²) proposed by Uchida et al. leads to accurate modeling of methane hydrate in porous media.

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引用次数: 0

An NMR study of hydrofluorocarbon mixed-gas solubility and self-diffusivity in the ionic liquid 1-ethyl-3-methylimidazolium dicyanamide

IF 2.8 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-01-16 DOI: 10.1016/j.fluid.2025.114340

Miguel Viar , Fernando Pardo , Gabriel Zarca , Leoncio Garrido , Ane Urtiaga

To date, the design of advanced separation processes, such as the extractive distillation with ionic liquids (ILs), for the separation of common close-boiling refrigerant blends relies almost exclusively on binary equilibrium data obtained for single-gas/solvent systems, thus neglecting the influence of possible mixture effects. In this work, Nuclear Magnetic Resonance (NMR) spectroscopy and pulsed gradient spin echo (PGSE) NMR are proposed for the sequential assessment of the single and mixed-gas vapor-liquid equilibrium and self-diffusivity of two fluorinated refrigerants, difluoromethane (R-32) and pentafluoroethane (R-125), in the IL 1-ethyl-3-methylimidazolium dicyanamide at 303.1 K and pressures up to 4 bar, either as pure R-32 or using the commercial refrigerant blend R-410A. The results confirmed that the mixed-gas solubility and self-diffusivities were essentially equal to those obtained with pure feed gas, thus significant mixing effects were not observed for this particular system. However, an increase in the self-diffusion coefficients was observed with the concentration of absorbed gas, which was more significant for the smallest hydrofluorocarbon (R-32) than for R-125. This technique also allowed evaluating the mobility of the IL moieties, which was slightly higher for the IL anion. Moreover, the self-diffusion coefficients of the IL ions also increased with the amount of gas absorbed, yet less markedly than for the refrigerants. Overall, the NMR technique proved to be an accurate method for the rapid screening of possible mixture effects in equilibrium and transport properties of refrigerant and IL systems, thus providing essential information for designing novel advanced separation processes.

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引用次数: 0

Hydrophobic interactions described using hetero-segmented PC-SAFT: 2. Surfactants and their aqueous solutions

IF 2.8 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-01-16 DOI: 10.1016/j.fluid.2025.114342

Marius Rother, Gabriele Sadowski

Despite their importance for industry and pharmaceuticals applications, description of aqueous solutions that contain surfactants is still a challenging task in thermodynamic modeling. As a first step towards a holistic modeling approach, which is also applicable for concentrated surfactant solutions, this work aimed to model the intrinsic behavior of surfactant molecules. For this purpose, we applied hetero-segmented PC-SAFT as a group contribution method to build surfactant molecules from different groups, which separately characterize the hydrophobic tail and the hydrophilic head of the surfactant. While the hydrophobic tail is modeled by the parameterization developed in the first part of this paper series (M. Rother, G. Sadowski, Fluid Phase Equilibria 582 (2024)), this work focuses on extending the parameter matrix to model the hydrophilic head. We considered the surfactant classes C_iG₁, C_iE_j and MEGA-i. The parameters for the surfactant head groups were adjusted to sorption data of surfactant/alcohol systems and to partition coefficients of the surfactants in n-alkane/water systems and n-alcohol/water systems. As a benchmark of the new parameterization, we modeled the critical micelle concentration as a function of temperature for these three surfactant classes using a newly developed, explicit equation for calculating this quantity. The results are in even quantitative agreement with the experimental data.

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引用次数: 0

Study of surface tension of CO2+water and CO2+ethanol solutions from combined CPA and PC-SAFT EoSs with gradient theory and artificial neural network

IF 2.8 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-01-13 DOI: 10.1016/j.fluid.2025.114338

Parisa Tabarzadi , Mohammad Niksirat , Fatemeh Aeenjan , Ariel Hernandez , Shahin Khosharay

The gradient theory of the interface was combined with the cubic plus association and perturbed chain statistical association fluid theory equations of state to describe the surface tension of (CO₂+ethanol) and (CO₂+water) systems. Two methods of phase equilibrium and two forms of influence parameters were applied to these systems. A novel influence parameter was also suggested for the gradient theory. The results of this study showed that the new proposed influence parameter results in the accuracy of the surface tension model. The lowest %AADs of surface tension were 2.37 and 6.02, for (CO₂+ethanol) and (CO₂+water) systems, respectively. Therefore, the accurate results of the surface tension were obtained for both systems. Then an artificial neural network model was developed to model the surface tension of the applied mixtures. The best results were obtained with 5 layers and 4 layers and using “trainlm” and “tansig” functions.

{"title":"Study of surface tension of CO2+water and CO2+ethanol solutions from combined CPA and PC-SAFT EoSs with gradient theory and artificial neural network","authors":"Parisa Tabarzadi , Mohammad Niksirat , Fatemeh Aeenjan , Ariel Hernandez , Shahin Khosharay","doi":"10.1016/j.fluid.2025.114338","DOIUrl":"10.1016/j.fluid.2025.114338","url":null,"abstract":"<div><div>The gradient theory of the interface was combined with the cubic plus association and perturbed chain statistical association fluid theory equations of state to describe the surface tension of (CO<sub>2</sub>+ethanol) and (CO<sub>2</sub>+water) systems. Two methods of phase equilibrium and two forms of influence parameters were applied to these systems. A novel influence parameter was also suggested for the gradient theory. The results of this study showed that the new proposed influence parameter results in the accuracy of the surface tension model. The lowest %AADs of surface tension were 2.37 and 6.02, for (CO<sub>2</sub>+ethanol) and (CO<sub>2</sub>+water) systems, respectively. Therefore, the accurate results of the surface tension were obtained for both systems. Then an artificial neural network model was developed to model the surface tension of the applied mixtures. The best results were obtained with 5 layers and 4 layers and using “trainlm” and “tansig” functions.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"593 ","pages":"Article 114338"},"PeriodicalIF":2.8,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143138299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thermodynamic perturbation coefficients for confined alkanes via Monte Carlo simulations

IF 2.8 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-01-13 DOI: 10.1016/j.fluid.2025.114333

Rodolfo José Amancio, Luís Fernando Mercier Franco

Modeling adsorption has been a challenge for more than a century. Different approaches within different scales have been proposed: from empirical models to equations of state, from classical Density Functional Theory to molecular simulations. Particularly equations of state are of interest for industrial applications. They are usually based on the assumption that the confinement effect can be simply added as a Helmholtz free energy contribution to the fluid–fluid Helmholtz energy. To verify this hypothesis, we propose a new conceptual framework to model the solid–fluid adsorption process, in which the reference fluid is a confined hard-chain, and the perturbation system contains the dispersion interactions among the fluid segments. Two strategies are employed: Barker–Henderson and Weeks–Chandler–Andersen. The solid material is conceived as an implicit wall imposing an external potential, a 10-4-3 Steele potential, on the fluid within a slit pore. The fluid–fluid interactions are described by a Mie potential. Applying Configurational-Bias Monte Carlo (CBMC) simulations, we compute the first- and second-order perturbation coefficients. Our findings show minimal confinement influence on the first perturbation coefficient. The second perturbation coefficient exhibits more complex behaviors, with divergences for short chains at high densities and long chains at low densities. These differences are due to preferred orientations and density peaks near confinement walls.

{"title":"Thermodynamic perturbation coefficients for confined alkanes via Monte Carlo simulations","authors":"Rodolfo José Amancio, Luís Fernando Mercier Franco","doi":"10.1016/j.fluid.2025.114333","DOIUrl":"10.1016/j.fluid.2025.114333","url":null,"abstract":"<div><div>Modeling adsorption has been a challenge for more than a century. Different approaches within different scales have been proposed: from empirical models to equations of state, from classical Density Functional Theory to molecular simulations. Particularly equations of state are of interest for industrial applications. They are usually based on the assumption that the confinement effect can be simply added as a Helmholtz free energy contribution to the fluid–fluid Helmholtz energy. To verify this hypothesis, we propose a new conceptual framework to model the solid–fluid adsorption process, in which the reference fluid is a confined hard-chain, and the perturbation system contains the dispersion interactions among the fluid segments. Two strategies are employed: Barker–Henderson and Weeks–Chandler–Andersen. The solid material is conceived as an implicit wall imposing an external potential, a 10-4-3 Steele potential, on the fluid within a slit pore. The fluid–fluid interactions are described by a Mie potential. Applying Configurational-Bias Monte Carlo (CBMC) simulations, we compute the first- and second-order perturbation coefficients. Our findings show minimal confinement influence on the first perturbation coefficient. The second perturbation coefficient exhibits more complex behaviors, with divergences for short chains at high densities and long chains at low densities. These differences are due to preferred orientations and density peaks near confinement walls.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"593 ","pages":"Article 114333"},"PeriodicalIF":2.8,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143138821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Acidic deep eutectic systems and their capacity to increase drug bioavailability

IF 2.8 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-01-11 DOI: 10.1016/j.fluid.2025.114332

Inês J. Ferreira, Cláudio C. Fernandes, Ana Rita C. Duarte

The pharmaceutical industry faces several challenges concerning the bioavailability of novel medications mainly because of their limited permeability and/or solubility. These are two crucial features that influence how well a medication is absorbed. The biopharmaceutics categorization system is a crucial instrument for the classification of active pharmaceutical ingredients (API) based on their permeability and solubility. In this work we explored the possibility of deep eutectic systems (DES) to be used as solubility and permeability enhancers of four different drugs supplied by Boeringher Ingelheim. In this investigation, the API's were dissolved in various DES and their solubility measured in PBS at 37 °C. Our findings suggest that CA: Gly: W (1:1:1) was able to increase the solubility of all four drugs in PBS, as well as their permeability. In summary, BI0001 and BI0002 following pre-solubilization in that system drugs shifted from class III to from class I included, whereas BI0005 still kept its class III classification although having higher solubility and permeability. The encouraging outcomes highlight DES's potential as a technique to boost drug's bioavailability.

{"title":"Acidic deep eutectic systems and their capacity to increase drug bioavailability","authors":"Inês J. Ferreira, Cláudio C. Fernandes, Ana Rita C. Duarte","doi":"10.1016/j.fluid.2025.114332","DOIUrl":"10.1016/j.fluid.2025.114332","url":null,"abstract":"<div><div>The pharmaceutical industry faces several challenges concerning the bioavailability of novel medications mainly because of their limited permeability and/or solubility. These are two crucial features that influence how well a medication is absorbed. The biopharmaceutics categorization system is a crucial instrument for the classification of active pharmaceutical ingredients (API) based on their permeability and solubility. In this work we explored the possibility of deep eutectic systems (DES) to be used as solubility and permeability enhancers of four different drugs supplied by Boeringher Ingelheim. In this investigation, the API's were dissolved in various DES and their solubility measured in PBS at 37 °C. Our findings suggest that CA: Gly: W (1:1:1) was able to increase the solubility of all four drugs in PBS, as well as their permeability. In summary, BI0001 and BI0002 following pre-solubilization in that system drugs shifted from class III to from class I included, whereas BI0005 still kept its class III classification although having higher solubility and permeability. The encouraging outcomes highlight DES's potential as a technique to boost drug's bioavailability.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"593 ","pages":"Article 114332"},"PeriodicalIF":2.8,"publicationDate":"2025-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143138876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0