Fluid Phase Equilibria最新文献

{"title":"A hybrid strategy for solving cubic equations of state based on a novel root discriminant method","authors":"Jun Zhao ,&nbsp;Luoyu Zhang ,&nbsp;Lili Wang ,&nbsp;Yushi Chen ,&nbsp;Wenying Zhao ,&nbsp;Shaohui Tao ,&nbsp;Shuguang Xiang","doi":"10.1016/j.fluid.2025.114466","DOIUrl":"10.1016/j.fluid.2025.114466","url":null,"abstract":"<div><div>The cubic equations of state (CEoS) is one of the most fundamental and popular models in chemical process simulation. This study aims to explore the impact of CEoS solution methods on the speed of process simulation and propose a simple and fast method to determine the single real root of CEoS at a single-phase state. Utilizing the advantages of this method, a hybrid CEoS solution strategy based on Cardano-Tartáglia’s formula and Newton-Raphson method (HCTNR) was developed. The average computation time is approximately 37 % of that of the Cardano-Tartáglia’s formula. The calculation speed of the new method is faster than that of the well-known Halley's method. Extensive examples of chemical process simulation were used to verify the speed and robustness of this method, and the results indicate that HCTNR can effectively improve the speed of process simulation while ensuring the accuracy of the calculation results.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"597 ","pages":"Article 114466"},"PeriodicalIF":2.8,"publicationDate":"2025-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143943098","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}

{"title":"Preface to the Special Issue on the XII Brazilian Conference on Applied Thermodynamics (CBTermo)","authors":"Lucio Cardozo-Filho ,&nbsp;Marcos L. Corazza ,&nbsp;Marcos R. Mafra ,&nbsp;Frederico W. Tavares","doi":"10.1016/j.fluid.2025.114464","DOIUrl":"10.1016/j.fluid.2025.114464","url":null,"abstract":"","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"596 ","pages":"Article 114464"},"PeriodicalIF":2.8,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144203646","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}

{"title":"Co-Oriented Fluid Functional Equation for Electrostatic interactions (COFFEE) for Mixtures: Phase Equilibria","authors":"Joshua Marx ,&nbsp;Kai Langenbach","doi":"10.1016/j.fluid.2025.114453","DOIUrl":"10.1016/j.fluid.2025.114453","url":null,"abstract":"<div><div>Predicting the phase equilibria of mixtures with thermodynamic equations of state (EOS) based on the perturbation theory approach is often challenging. In particular, when combining pure components with different polar properties, state-dependent parameters are often required to achieve a satisfactory description of the phase behavior. A likely reason for this is that EOS typically do not take the changes in the intermolecular fluid structure that result from the polar interactions into account. Instead it is assumed that the fluid retains the structure of a simpler reference fluid, e.g. a hard sphere fluid. The Co-Oriented Fluid Functional Equation for Electrostatic interactions (COFFEE) was developed to address this challenge. Within the framework of COFFEE the dipolar contribution to the free energy is separated into a near field and a far field contribution. Within the near field, which corresponds roughly to the first coordination shell around a central particle, the free energy is expanded around the fully perturbed state which makes it possible to consider the preferential orientations between neighboring particles directly. For this purpose, the free energy is formulated as a functional of the orientation distribution function (ODF), which describes mutual orientations in a statistical way. The far field is handled as in classic perturbation theories. COFFEE is based on the Stockmayer (ST) model fluid which consists of a Lennard Jones (LJ) fluid with a superimposed point dipole. COFFEE has been used to describe and predict the ODF in pure ST fluids and mixtures containing ST fluids with both central and decentral dipoles. Furthermore, COFFEE can accurately describe the phase behavior of these fluids as well as simple real fluids like hydrogen chloride while showing improvements over comparable approaches. In this contribution, the far field contribution of COFFEE is newly parametrized. This is necessary because the near field contribution was adjusted in previous work. COFFEE is then employed to predict the vapor-liquid equilibria (VLE) of mixtures containing ST, shifted ST (sST, decentral dipole) and LJ fluids. Results are compared to molecular simulation data and show improvements over a comparable EOS in several cases. Finally, the VLE for the three binary mixtures of acetone, acetonitrile, and methanol is calculated and compared to experimental results and results obtained with PCP-SAFT. COFFEE predicts the VLE of mixtures containing methanol more accurately than PCP-SAFT while being slightly less accurate for the acetone-acetonitrile mixture.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"597 ","pages":"Article 114453"},"PeriodicalIF":2.8,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144105932","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}

{"title":"A semi-theoretical phase equilibrium equation for methane hydrate accounting for physicochemical properties and inter-grain arrangement of sediment","authors":"Xudong Zhang ,&nbsp;Mingjing Jiang ,&nbsp;Huaning Wang","doi":"10.1016/j.fluid.2025.114463","DOIUrl":"10.1016/j.fluid.2025.114463","url":null,"abstract":"<div><div>The phase equilibrium equation for methane hydrate (MH) is influenced by the pore size within soils and the physicochemical properties of the soil minerals. Therefore, we presented a semi-theoretical phase equilibrium equation for MH in sediments that accounts for both pore size and physicochemical characteristics. First, we examined the relationship between pore size and sample porosity, interparticle angles, and the shape of interparticle cementation. Subsequently, we characterized the relationships among pore size, water content, and the new phase equilibrium equation, considering capillary pressure and bound water content. Finally, we validated the phase equilibrium equation with experimental data available in the literature. Our findings indicate that low water content inhibits hydrate formation, while greater pore sizes enhance MH formation. Additionally, a simultaneous reduction in both pore size and water content significantly inhibits hydrate formation.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"597 ","pages":"Article 114463"},"PeriodicalIF":2.8,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143928703","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}

{"title":"Enhancing swelling kinetics of pNIPAM lyogels: The role of crosslinking, copolymerization, and solvent","authors":"Kathrin Marina Eckert ,&nbsp;Jelisa Bonsen ,&nbsp;Anja Hajnal ,&nbsp;Johannes Gmeiner ,&nbsp;Jonah Hasse ,&nbsp;Muhammad Adrian ,&nbsp;Julian Karsten ,&nbsp;Patrick A. Kißling ,&nbsp;Alexander Penn ,&nbsp;Bodo Fiedler ,&nbsp;Gerrit A. Luinstra ,&nbsp;Irina Smirnova","doi":"10.1016/j.fluid.2025.114462","DOIUrl":"10.1016/j.fluid.2025.114462","url":null,"abstract":"<div><div>Stimuli-responsive lyogels are known for their ability to undergo significant macroscopic changes when exposed to external stimuli. While thermo-responsive gels, such as poly-N-isopropylacrylamide (pNIPAM), have been extensively studied across various applications, solvent-induced swelling has predominantly been investigated in aqueous solutions. This study explores the tailoring of lyogel formulations for future applications by controlling their solvent-induced swelling behavior, comparing both homopolymeric and semi-interpenetrating polymer networks (semi-IPNs). It is structured in two parts: the first focuses on characterization techniques, including NMR relaxometry, swelling degree measurements, mechanical testing, and SEM analysis, while the second part delves into swelling kinetic analysis, applying solvent exchange as a stimulus for varying gel formulations and solvents. In contrast to most previous studies, the impact of chemical and physical crosslinking, as well as copolymer inclusion, on the swelling behavior and mechanical properties of lyogels in organic solvents is examined and compared with solvent-induced swelling kinetics measurements. The results demonstrate that increasing chemically crosslinking in homopolymers and physically crosslinking in semi-IPNs enhances mechanical stability, while improving mass transport properties and solvent exchange kinetics. However, increases degree of crosslinking results in a prolonged response time to the solvent exchange stimulus and a reduction in the overall swelling capacity of the lyogels. Furthermore, variations in solvent properties, including molecular size and diffusion rates, significantly influence the swelling kinetics, whereas smaller, faster-diffusing solvents leading to more pronounced solvent spillage effects. Our findings highlight the complex interplay between gel formulation, network structure, and solvent nature in determining the solvent-induced swelling kinetics of lyogels, providing insights into how these materials can be tailored for specific applications especially those requiring short response times and optimized mechanical properties.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"597 ","pages":"Article 114462"},"PeriodicalIF":2.8,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143922164","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}

{"title":"Thermodynamic perturbation theory for associating fluids with coupling to isotropic attractions","authors":"Bennett D. Marshall","doi":"10.1016/j.fluid.2025.114461","DOIUrl":"10.1016/j.fluid.2025.114461","url":null,"abstract":"<div><div>The coupling between dispersion and hydrogen bonding attractions is mostly ignored in the development of equations of state for hydrogen bonding fluids. While a reasonable approximation in the development of semi-empirical equations of state, the independence of hydrogen bonding and dispersion attractions is not rigorously justifiable. Both hydrogen bonding and dispersion attractions result from the interaction of electrons between two molecules, hence they emerge from the same underlying phenomena. In the pursuit of more accurate equations of state, including the coupling between hydrogen bonding and dispersion attractions in a self-consistent manner should be explored. In this work the coupling of dispersion and hydrogen bonding attractions is incorporated in the development of Wertheim’s thermodynamic perturbation theory for hydrogen bonding molecules. The developed theory is general for pure hydrogen bonding fluids with any number of association sites. The theory is applied to the case of hard spheres with isotropic square well attractions and a single association site. The theory gives counter intuitive predictions.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"597 ","pages":"Article 114461"},"PeriodicalIF":2.8,"publicationDate":"2025-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143916310","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}

{"title":"A theoretical model of gas-liquid phase transition near the critical point","authors":"Wenbin Liu ,&nbsp;Jing Liu","doi":"10.1016/j.fluid.2025.114456","DOIUrl":"10.1016/j.fluid.2025.114456","url":null,"abstract":"<div><div>In this study, the internal pressure strength term in the Van der Waals multiphase interface equation has been adjusted to better fit the interface region. By applying the principle of normal isopressure, we can ascertain the thickness of the gas-liquid interface and the material's density distribution along the normal direction. At the gas-liquid interface, molecules experience both an attractive force pulling them into the liquid and a repulsive force from collisions with the gas. By considering the combined effect of these two forces, we can derive an expression for the latent heat of evaporation that includes the molecular volume parameter b, using the normal path integral. This expression is capable of predicting the latent heat of evaporation for substances like water, ranging from the boiling point to the critical point. The maximum deviation for conventional substances is under 30 %, while the prediction error using the Boltzmann distribution ranges from 40 % to 60 %. After introducing the dimensionless parameter τ_c, the maximum prediction deviation for H₂O drops to below 8 %, significantly enhancing the prediction accuracy for other substances as well. For subcritical temperatures (T_c-3 <em>K</em> &lt; <em>T</em>&lt; T_c), the new expression successfully predicts the latent heat of evaporation for over 30 substances, with an error margin of no &gt;1 %. Additionally, it predicts the critical volume of a substance with a deviation of no &gt;2.4 %. Thus, the latent heat of evaporation expression that incorporates molecular volume parameters demonstrates excellent predictive capability in the gas-liquid phase transition process near critical temperatures, providing a foundation for advancing the average field theory of gas-liquid phase transitions for various substances at near-critical temperatures.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"597 ","pages":"Article 114456"},"PeriodicalIF":2.8,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143922165","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}

{"title":"Thermodynamic description of aqueous solutions of silver nitrate: Experimental and modeling","authors":"Mouad Arrad ,&nbsp;Mehriban Aliyeva ,&nbsp;Mónia A.R. Martins ,&nbsp;Kaj Thomsen ,&nbsp;Simão P. Pinho","doi":"10.1016/j.fluid.2025.114459","DOIUrl":"10.1016/j.fluid.2025.114459","url":null,"abstract":"<div><div>The water activity of silver nitrate solutions was measured at 298.2 K and 313.2 K using a humidity sensor instrument. Concentrations of silver nitrate up to almost saturation were included. The thermodynamic properties of the system were described by the Pitzer model, the specific interaction theory (SIT), and the Extended UNIQUAC model. The interaction parameters for the models were estimated using experimental freezing points, osmotic coefficients, and solubility for silver nitrate aqueous solutions collected from the open literature, as well as the water activity data measured in this work. Pitzer and SIT parameters were applied by introducing a temperature dependency, enabling these models to cover a more comprehensive temperature range and extrapolate the calculation to higher molalities. Both approaches represent the data satisfactorily up to moderate molalities. The Extended UNIQUAC model, with its built-in temperature dependence, provides the best thermodynamic description of this binary system. It has a very satisfactory solubility diagram and a good description of the osmotic and activity coefficients.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"597 ","pages":"Article 114459"},"PeriodicalIF":2.8,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143906003","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}

{"title":"Corrigendum to “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” [Fluid Phase Equilibria, volume 593C, FLUID 114338]","authors":"Parisa Tabarzadi ,&nbsp;Mohammad Niksirat ,&nbsp;Fatemeh Aeenjan ,&nbsp;Ariel Hernandez ,&nbsp;Shahin Khosharay","doi":"10.1016/j.fluid.2025.114452","DOIUrl":"10.1016/j.fluid.2025.114452","url":null,"abstract":"","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"595 ","pages":"Article 114452"},"PeriodicalIF":2.8,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144148018","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}

{"title":"Let us rethink advanced mixing rules for cubic equations of state","authors":"Romain Privat ,&nbsp;Jean-Noël Jaubert ,&nbsp;Georgios M. Kontogeorgis","doi":"10.1016/j.fluid.2025.114455","DOIUrl":"10.1016/j.fluid.2025.114455","url":null,"abstract":"&lt;div&gt;&lt;div&gt;One of the most challenging aspects of using a Van der Waals type equation of state for mixtures is determining the appropriate expressions for the coefficients &lt;span&gt;&lt;math&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt; (attractive parameter) and &lt;span&gt;&lt;math&gt;&lt;mi&gt;b&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt; (covolume) involved in this equation. It has been 45 years since Huron and Vidal first proposed the “EoS/&lt;span&gt;&lt;math&gt;&lt;msup&gt;&lt;mi&gt;g&lt;/mi&gt;&lt;mi&gt;E&lt;/mi&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt;” advanced mixing rules. By equating under infinite reference pressure, the mathematical expression of the excess Gibbs energy &lt;span&gt;&lt;math&gt;&lt;msup&gt;&lt;mi&gt;g&lt;/mi&gt;&lt;mi&gt;E&lt;/mi&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt; derived from an equation of state, to the same quantity issued from an explicit activity coefficient model, they deduced an expression for the ratio &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;mo&gt;/&lt;/mo&gt;&lt;mi&gt;b&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;. A decade after Huron and Vidal’s initial proposal, building upon the original proposal, Michelsen subsequently derived the “zero reference pressure” (ZRP) approach and proposed the approximate ZRP mixing rules MHV1 and MHV2. Throughout the 1990′s and 2000′s, the Huron-Vidal and ZRP approaches were subject, often empirically, to multiple revisions in order to remedy some of their well identified shortcomings. It would appear that the debates surrounding advanced mixing rules are now over, with the latest conclusions proposed in the 2000s enjoying a degree of consensus.&lt;/div&gt;&lt;div&gt;The objective of this article is to reopen the debate in light of the scientific insights gained from our recent research on advanced mixing rules for cubic equations of state. The concept of deriving mixing rules by equating the excess Gibbs energy expressed from an equation of state to the same quantity expressed from an activity coefficient model (this equality is called a “&lt;em&gt;matching equation”&lt;/em&gt;) was undoubtedly an appealing one. However, experience has shown that such a matching equation is not without its limitations, particularly due to the lack of sufficient constraints. We have reached the conclusion that the only way to derive advanced mixing rules that are free from shortcomings is to ensure that not only are the complete expressions of &lt;span&gt;&lt;math&gt;&lt;msup&gt;&lt;mi&gt;g&lt;/mi&gt;&lt;mi&gt;E&lt;/mi&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt; from an equation of state and from an activity coefficient model equal but also that the three separate contributions that make it up (i.e., combinatorial, residual and the product of the pressure by the excess volume &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;P&lt;/mi&gt;&lt;mo&gt;·&lt;/mo&gt;&lt;msup&gt;&lt;mi&gt;v&lt;/mi&gt;&lt;mi&gt;E&lt;/mi&gt;&lt;/msup&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;) are equal. As discussed in this paper, achieving this objective is challenging and we conclude that the best and unique solution for developing safe mixing rules is to modify the matching equation proposed by Huron-Vidal and Michelsen and to only equate the residual contributions.&lt;/div&gt;&lt;div&gt;Based on this observation, we demonstrate how the demonstrations of the ZRP and HV mixing rules can be reworked to arrive at a unique and univers","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"596 ","pages":"Article 114455"},"PeriodicalIF":2.8,"publicationDate":"2025-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144203648","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}