Fluid Phase Equilibria最新文献_第9页

Impact of nanostructuration on the transport properties of ionic liquids 纳米结构对离子液体输运性质的影响

IF 2.8 3区工程技术

Fluid Phase Equilibria Pub Date : 2025-04-26 DOI: 10.1016/j.fluid.2025.114458

Carlos F.P. Miranda, Luís M.N.B.F. Santos

{"title":"Impact of nanostructuration on the transport properties of ionic liquids","authors":"Carlos F.P. Miranda, Luís M.N.B.F. Santos","doi":"10.1016/j.fluid.2025.114458","DOIUrl":"10.1016/j.fluid.2025.114458","url":null,"abstract":"<div><div>The impact of nanostructuration on the transport properties of ionic liquids (ILs) was explored by a systematic and high-resolution study of the temperature dependence of the viscosity and electrical conductivity of seven ILs homolog series: [C<em><sub>n</sub></em>C<sub>1</sub>im]BF<sub>4</sub>, [C<em><sub>n</sub></em>C<sub>1</sub>im]PF<sub>6</sub>, [C<em><sub>n</sub></em>C<sub>1</sub>im][OTf], [C<em><sub>n</sub></em>C<sub>1</sub>im][FAP], [C<em><sub>n</sub></em>C<sub>1</sub>im][NTf<sub>2</sub>], [C<em><sub>n</sub></em>C<sub>1</sub>pyr][NTf<sub>2</sub>], [C<em><sub>n</sub></em>py][NTf<sub>2</sub>]. The increase of the alkyl chain length was found to increase the viscosity and decrease the molar conductivity due to a reduction of the overall mobility of the liquid and enhancement of the van der Waals interactions. The temperature dependency of transport properties was fitted to the Vogel-Fulcher-Tammann equation (VFT), and the energy barrier and pre-exponential coefficients were derived. The obtained results highlight the trendshift (<em>n</em> = 6–7) in the profile of the transport properties, which is a reflection of the intensification of nanostructuration and describes the transition from a liquid with a strong ionic character to a nanostructured liquid dominated by the hydrophobic domain. The derived energy barriers were found to correspond to around 0.2–0.35 of the cohesive interactions of the ionic liquids, with the spherical anions BF<sub>4</sub><sup>−</sup> and PF<sub>6</sub><sup>−</sup> showing a higher fraction than the more stretched and larger anions, such as NTf<sub>2</sub>. This fraction was found to not be affected by the alkyl chain length. The increase of the nonpolar region was also reflected in a more pronounced deviation from the ideal Walden relation. This highlights the increased complexity of the electric conductivity when compared with viscosity due to the heterogeneity of charge distribution, revealing the impact of ionic surface-volume ratio and anion-cation size ratio.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"597 ","pages":"Article 114458"},"PeriodicalIF":2.8,"publicationDate":"2025-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143916309","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

Investigation of the molecular architecture influence on the solid-liquid transition of ethylene/1-octene copolymers in butylal 丁醛中乙烯/1-辛烯共聚物固液转变的分子结构影响研究

IF 2.8 3区工程技术

Fluid Phase Equilibria Pub Date : 2025-04-26 DOI: 10.1016/j.fluid.2025.114457

Jana Zimmermann, Zengxuan Fan, Matti Jänicke, Michael Fischlschweiger

{"title":"Investigation of the molecular architecture influence on the solid-liquid transition of ethylene/1-octene copolymers in butylal","authors":"Jana Zimmermann, Zengxuan Fan, Matti Jänicke, Michael Fischlschweiger","doi":"10.1016/j.fluid.2025.114457","DOIUrl":"10.1016/j.fluid.2025.114457","url":null,"abstract":"<div><div>The molecular architecture, in terms of molecular weight and branching, linked with the semi-crystallinity of the polymer, plays a key role in solid-liquid equilibria in polyethylene-solvent systems. Lattice Cluster Theory, in combination with continuous thermodynamics, captures these molecular features and has been successfully applied in the past to predict solid-liquid equilibria of polymer solvent systems. While the solubility of linear low-density polyethylenes in chlorinated solvents has been studied in depth in the past, few investigations have addressed their solubility in less toxic and environmentally more friendly solvents, particularly in relation to the influence of molecular architecture. This study aims to fill this gap by investigating the relationship between molecular architecture of ethylene/1-octene copolymers, covering a wide range of branching levels from 3.5 to 54.6 CH/1000 C, and their solid-liquid phase transitions in butylal. By combining cross-fractionation chromatography, preparative crystallisation fractionation and Lattice Cluster Theory, the solid-liquid transitions of these material systems are elucidated and an architecture-solubility relationship is established. This approach provides detailed insights into how molecular architecture influences crystallisation behaviour, provides a basis for the design of ethylene/1-octene copolymer fractions with tailored microstructural features, and demonstrates the predictive power of Lattice Cluster Theory.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"597 ","pages":"Article 114457"},"PeriodicalIF":2.8,"publicationDate":"2025-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143895131","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

Freezing transitions in colloidal nanoparticles: Interplay of dispersive and electrostatic interactions in confined two-dimensional systems 胶体纳米颗粒中的冻结转变：在受限的二维系统中色散和静电相互作用的相互作用

IF 2.8 3区工程技术

Fluid Phase Equilibria Pub Date : 2025-04-25 DOI: 10.1016/j.fluid.2025.114448

Moushila Bayen, Anupam Kumar, Pankaj Mishra

引用次数: 0

Thermodynamic modeling of poorly specified mixtures using NMR fingerprinting and group-contribution equations of state 使用核磁共振指纹和群体贡献状态方程的不良指定混合物的热力学建模

IF 2.8 3区工程技术

Fluid Phase Equilibria Pub Date : 2025-04-24 DOI: 10.1016/j.fluid.2025.114446

Jens Wagner, Zeno Romero, Kerstin Münnemann, Thomas Specht, Fabian Jirasek, Hans Hasse

{"title":"Thermodynamic modeling of poorly specified mixtures using NMR fingerprinting and group-contribution equations of state","authors":"Jens Wagner, Zeno Romero, Kerstin Münnemann, Thomas Specht, Fabian Jirasek, Hans Hasse","doi":"10.1016/j.fluid.2025.114446","DOIUrl":"10.1016/j.fluid.2025.114446","url":null,"abstract":"<div><div>Mixtures of which the composition is only partially known are ubiquitous in chemical and biotechnological processes and pose a significant challenge for process design and optimization since classical thermodynamic models require complete speciation, which cannot be obtained with reasonable effort in many situations. In prior work, we have introduced a framework combining standard nuclear magnetic resonance (NMR) experiments and machine-learning (ML) algorithms for the automated elucidation of the group composition of unknown mixtures and the rational definition of pseudo-components and have applied the results together with group-contribution (GC) models of the Gibbs excess energy. In the present work, we extend this approach to the application of group-contribution equations of state (GC-EOS), enabling the predictive modeling of basically all thermodynamic properties of such mixtures. As an example, we discuss the application of the SAFT-<span><math><mi>γ</mi></math></span> Mie GC-EOS for predicting the CO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> solubility in several test mixtures of known composition. However, the information on their composition was not used in applying our method; it was only used to generate reference results with the SAFT-<span><math><mi>γ</mi></math></span> Mie EOS that were compared to the predictions from our method. In addition, the CO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> solubility in the test mixtures was also determined experimentally by NMR spectroscopy. The results demonstrate that the new approach for modeling poorly specified mixtures also works with GC-EOS, which further extends its applicability in process design and optimization.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"596 ","pages":"Article 114446"},"PeriodicalIF":2.8,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143873745","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

High-pressure phase equilibria of liquid CO2 with ethanol - water mixtures 液态CO2与乙醇-水混合物的高压相平衡

IF 2.8 3区工程技术

Fluid Phase Equilibria Pub Date : 2025-04-24 DOI: 10.1016/j.fluid.2025.114450

Masato Urabe , Masaki Ota , Richard Lee Smith Jr. , Masaru Watanabe

{"title":"High-pressure phase equilibria of liquid CO2 with ethanol - water mixtures","authors":"Masato Urabe , Masaki Ota , Richard Lee Smith Jr. , Masaru Watanabe","doi":"10.1016/j.fluid.2025.114450","DOIUrl":"10.1016/j.fluid.2025.114450","url":null,"abstract":"<div><div>Although many data have been reported for the CO<sub>2</sub> (1) - ethanol (2) - water (3) system, gaps in the literature exist for liquid CO<sub>2</sub> at conditions where stripping of ethanol for flavor fractionation has been suggested. In this work, a flow-type device was used to measure the phase equilibria of CO<sub>2</sub> - ethanol - water mixtures at (278 to 298) K and (8 to 20) MPa. Ethanol/water feed ratios were varied from 0.22 to 1.7 which gave corresponding equilibrium ratios (=<em>y</em><sub>i</sub>/<em>x</em><sub>i</sub>) of <em>K</em><sub>1</sub> (39 to 4), <em>K</em><sub>2</sub> (0.12 to 0.21) and <em>K</em><sub>3</sub> (0.006 to 0.04) giving ethanol/water selectivities, <em>β</em> (=<em>K</em><sub>2</sub>/<em>K</em><sub>3</sub>), that ranged from 27.9 to 5. While the <em>K</em><sub>2</sub> values tended to be invariant with ethanol/water feed ratio, the <em>K</em><sub>1</sub> and <em>K</em><sub>3</sub> values varied greatly. Among the equations of state evaluated in this work, the Peng-Robinson equation of state with the Wong-Sandler mixing rule model based on the NRTL activity coefficient expression gave the lowest deviations and could correlate <em>K</em> values for CO<sub>2</sub>, ethanol and water with an average relative deviation of 6.9 %, 22.3 % and 28.1 %, respectively.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"597 ","pages":"Article 114450"},"PeriodicalIF":2.8,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143895130","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

Vapor–liquid and liquid–liquid equilibrium in mixtures of water + isobutanol/n-butanol + isobutylal/n-butylal 水+异丁醇/正丁醇+异丁醛/正丁醛混合物的汽液平衡和液液平衡

IF 2.8 3区工程技术

Fluid Phase Equilibria Pub Date : 2025-04-22 DOI: 10.1016/j.fluid.2025.114440

Lukas Winklbauer, Jieyu Qian, Jakob Burger

引用次数: 0

Effect of MgCl2 and pressure on vapor-liquid equilibrium in separation of water in water + ethylene glycol system MgCl2和压力对水+乙二醇体系中水分离汽液平衡的影响

IF 2.8 3区工程技术

Fluid Phase Equilibria Pub Date : 2025-04-22 DOI: 10.1016/j.fluid.2025.114451

Weichao Tang , Mengjie Luo , Hang Chen , Xingfu Song

{"title":"Effect of MgCl2 and pressure on vapor-liquid equilibrium in separation of water in water + ethylene glycol system","authors":"Weichao Tang , Mengjie Luo , Hang Chen , Xingfu Song","doi":"10.1016/j.fluid.2025.114451","DOIUrl":"10.1016/j.fluid.2025.114451","url":null,"abstract":"<div><div>In the process of preparing anhydrous magnesium chloride by the alcohol-ammonia method using ethylene glycol (EG) as the solvent, the dehydration process of the water + EG + magnesium chloride (MgCl<sub>2</sub>) system is crucial. Therefore, this work analyzed the effect of MgCl<sub>2</sub> and pressure on vapor-liquid equilibrium in separation of water in water + ethylene glycol system. The isobaric vapor-liquid equilibrium (VLE) data for the water + EG + MgCl<sub>2</sub> system were measured at 101.3 kPa with MgCl<sub>2</sub> mass fractions of 0, 0.05, 0.07, and 0.10. It was found that the addition of MgCl<sub>2</sub> raised the phase equilibrium temperature of the water + EG system and decreased the relative volatility of water relative to EG. Additionally, the VLE data for the water + EG + MgCl<sub>2</sub> system at 71.3, 41.3 and 11.3 kPa were measured with the MgCl<sub>2</sub> mass fraction of 0.10. The equilibrium temperature was effectively lowered, and the relative volatility was significantly increased by reducing the system pressure. The experimental data obtained in this work was consistent in thermodynamics test through Van Ness method. Moreover, the NRTL model was used to correlate experimental data. The root - mean - square deviations between the measured and calculated values of temperature (T) and vapor phase mole fraction (y<sub>1</sub>) were less than 0.53 K and 0.006 respectively. The NRTL model prediction with the regressed parameters was found in agreement with the experimental data.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"596 ","pages":"Article 114451"},"PeriodicalIF":2.8,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143882862","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 properties of some aqueous ionic liquid solutions using ion-SAFT-VR EOS 离子液体水溶液热力学性质的离子- saft - vr EOS研究

IF 2.8 3区工程技术

Fluid Phase Equilibria Pub Date : 2025-04-18 DOI: 10.1016/j.fluid.2025.114447

Ayeh Emrani, Ali Maghari

{"title":"Thermodynamic properties of some aqueous ionic liquid solutions using ion-SAFT-VR EOS","authors":"Ayeh Emrani, Ali Maghari","doi":"10.1016/j.fluid.2025.114447","DOIUrl":"10.1016/j.fluid.2025.114447","url":null,"abstract":"<div><div>The statistical association fluid theory (SAFT) approach for attractive potentials of variable range combined with interionic interactions, to describe some aqueous solutions of imidazolium ionic liquids (ILs) with different anion structures. The anions analyzed encompass [SCN]<sup>-</sup>, [DCA]<sup>–</sup>, [BF4]<sup>-</sup>, [NTF<sub>2</sub>]<sup>-</sup> and [PF<sub>6</sub>]<sup>-</sup> which show the effect of systematically change of the substituents on the anion. The proposed equation of state is a combination of a square-well variable range and a mean spherical approximation (MSA) corresponding to the restrictive primitive model to describe the long-range interactions of ILs. Water is characterized as a bipolar associating liquid combining the four-site model and a square-well potential with a constant dielectric continuum. The accurate predictions of volumetric properties for pure ILs and <span><math><mrow><mi>p</mi><mi>ρ</mi><mi>T</mi></mrow></math></span> of water as well as the thermodynamic properties of binary aqueous IL solutions are significant evidence of the capability and excellent performance of the ion-SAFT-VR model. Parameters of the new version of the model have been reported and the model tested for an impressively large number of data sets. For binary mixtures of ILs and water, binary interaction coefficients were obtained by fitting experimental data at constant pressure and phase concentrations. The results show the satisfactory predictability of the ion-SAFT-VR EOS in modeling the thermodynamic properties of bulk systems, which indicates the reliability of the employed EOS. Due to the excellent results obtained for pure IL densities and the satisfactory results observed for aqueous solution of ILs, we can confidently conclude that the approach provides an overall commendable description of most IL systems.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"596 ","pages":"Article 114447"},"PeriodicalIF":2.8,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143863664","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

Adsorption-based separation of refrigerant blends using ZIF-7 and ZIF-8: Isothermal high-pressure gravimetric sorption measurements 基于吸附的分离制冷剂混合物使用ZIF-7和ZIF-8：等温高压重力吸附测量

IF 2.8 3区工程技术

Fluid Phase Equilibria Pub Date : 2025-04-17 DOI: 10.1016/j.fluid.2025.114449

Gensheng Lin , Xiaoxian Yang , Ehsan Sadeghi Pouya , Eric F. May , Markus Richter

{"title":"Adsorption-based separation of refrigerant blends using ZIF-7 and ZIF-8: Isothermal high-pressure gravimetric sorption measurements","authors":"Gensheng Lin , Xiaoxian Yang , Ehsan Sadeghi Pouya , Eric F. May , Markus Richter","doi":"10.1016/j.fluid.2025.114449","DOIUrl":"10.1016/j.fluid.2025.114449","url":null,"abstract":"<div><div>A high-pressure gravimetric sorption analyzer incorporating a magnetic suspension balance was set up for simultaneous density and sorption measurements in the temperature range of (273.15–368.15) K and pressures up to 15 MPa. The reliability of the apparatus was first examined by density measurements of four pure gases (nitrogen, carbon dioxide, argon, and methane) at temperatures of (283.15–333.15) K with pressures up to 12 MPa. The expanded uncertainties (<em>k</em> = 2) were estimated to be 60 mK for temperature, 0.2 or 3.0 kPa for pressure, and 0.1 % for pure fluid density determination. The density data measured with the newly commissioned apparatus were compared to values calculated with reference equations of state as implemented in the NIST REFPROP database version 10.0, with relative deviations mostly within 0.1 % after calibration. The apparatus was further validated through methane sorption measurements on ZIF-7, showing excellent agreement with data obtained from another well-calibrated gravimetric adsorption analyzer that has been extensively used for accurate measurements. Following this validation, the adsorption of six pure refrigerant gases (R-32, R-125, R-1234yf, R-134a, R-1234ze(E), and R-290) on ZIF-7 and ZIF-8 was studied to explore their potential for refrigerant blend separation (e.g., R-410A and R-513A). The results indicate that ZIF-8 could effectively separate R-32 from R-410A, while ZIF-7 has the potential to separate both R-32 from R-410A and R-1234yf from R-513A.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"597 ","pages":"Article 114449"},"PeriodicalIF":2.8,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143937331","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

Solubility of water in bitumen 水在沥青中的溶解度

IF 2.8 3区工程技术

Fluid Phase Equilibria Pub Date : 2025-04-15 DOI: 10.1016/j.fluid.2025.114442

B. Zuluaga, F.F. Schoeggl, H.W. Yarranton

{"title":"Solubility of water in bitumen","authors":"B. Zuluaga, F.F. Schoeggl, H.W. Yarranton","doi":"10.1016/j.fluid.2025.114442","DOIUrl":"10.1016/j.fluid.2025.114442","url":null,"abstract":"<div><div>Liquid/liquid-vapor (L/LV) and aqueous-liquid/aqueous-liquid-vapor (AL/ALV) boundaries of pseudo-binary mixtures of bitumen and water were measured using the isothermal stepwise volume expansion method at conditions relevant to <em>in situ</em> heavy oil operations (temperatures from 180 to 280 °C and pressures from 1.5 to 5 MPa). The L/AL boundary was determined from the intersection of the L/LV and AL/ALV boundaries. An activity coefficient model of the pseudo-binary system was used to check the self-consistency of the L/LV measurements. The Advanced Peng Robinson equation of state, which has a distinct alpha function for water, was used to model the VLE and VLLE data. For this model, the oil was characterized into pseudo-components based on a SimDist assay and the specific gravity and asphaltene content of the oil. Temperature dependent binary interaction parameters between bitumen pseudo-components and water were tuned such that the model fit the measurements to within the experimental error. Isothermal pressure-composition phase diagrams were generated for the pseudo-binary mixtures at each temperature. Finally, a straightforward correlation for the solubility limit of water in bitumen as a function of temperature was developed using the data in this study and from the literature. The average deviation of the correlation was 0.5 wt % below 340 °C.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"596 ","pages":"Article 114442"},"PeriodicalIF":2.8,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143834442","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