Fluid Phase Equilibria最新文献_第6页

Solubility behavior of diosmetin in pure and binary solvents: Thermodynamic evaluation and molecular-level interpretation 薯蓣皂苷在纯溶剂和二元溶剂中的溶解度行为：热力学评价和分子水平解释

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-11-01 DOI: 10.1016/j.fluid.2025.114611

Yanni Li , Yuyang Zhang , Mengqing Qi , Lihui Yi , Yiyang Yu , Wenge Yang , Yonghong Hu

Diosmetin, a natural flavonoid compound, has been demonstrated to exhibit significant neuroprotective effects by inhibiting neuroinflammation and oxidative stress, thereby ameliorating the pathological progression of Alzheimer's disease. However, its current industrial production primarily relies on chemical synthesis, where solvent selection critically impacts reaction efficiency and product purity, consequently limiting its large-scale pharmaceutical applications. This study systematically investigated the solubility behavior of diosmetin in ten pure solvents and three binary solvent systems within a temperature range of 278.15 to 323.15 K. The solubility data were accurately determined using the static equilibrium-high performance liquid chromatography method, while the solvent effects were mechanistically elucidated through an innovative combination of Hansen solubility parameters and the KAT-LSER model. By establishing a multidimensional thermodynamic correlation framework including the modified Apelblat model, λh model, CNIBS/R-K model, Jouyban-Acree model, and SUN model, the study revealed that solubility exhibited a positive correlation with temperature, with N,N-dimethylformamide demonstrating the optimal dissolution performance. Thermodynamic analysis revealed the dissolution process to be endothermic, entropy-driven and non-spontaneous, with hydrogen-bond basicity/polarity enhancing solubility while cohesion energy inhibited it. The modified Apelblat and CNIBS/R-K models exhibited optimal predictive accuracy for pure and binary systems respectively. These findings provide a crucial theoretical foundation for solvent screening and process optimization in the industrial production of diosmetin.

薯蓣皂苷是一种天然类黄酮化合物，已被证明具有显著的神经保护作用，通过抑制神经炎症和氧化应激，从而改善阿尔茨海默病的病理进展。然而，其目前的工业生产主要依赖于化学合成，其中溶剂选择严重影响反应效率和产品纯度，从而限制了其大规模的制药应用。本研究系统地研究了薯蓣皂苷在10种纯溶剂和3种二元溶剂体系中的溶解度，温度范围为278.15 ~ 323.15 K。溶解度数据采用静态平衡-高效液相色谱法精确测定，溶剂效应通过Hansen溶解度参数和KAT-LSER模型的创新组合进行机理分析。通过建立包括修正Apelblat模型、λh模型、CNIBS/R-K模型、Jouyban-Acree模型和SUN模型在内的多维热力学关联框架，研究发现，N，N-二甲基甲酰胺溶解度与温度呈正相关，其中N，N-二甲基甲酰胺溶出性能最佳。热力学分析表明，溶解过程是吸热的、熵驱动的非自发的，氢键的碱性/极性增强了溶解度，而内聚能抑制了溶解度。改进的Apelblat模型和CNIBS/R-K模型分别对纯体系和二元体系具有最佳的预测精度。这些研究结果为薯蓣皂苷工业生产中的溶剂筛选和工艺优化提供了重要的理论依据。

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引用次数: 0

Water/polyethylene glycol/sodium citrate: from the aqueous two-phase system to the complete phase diagram 水/聚乙二醇/柠檬酸钠：从水两相体系到完整的相图

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-11-01 DOI: 10.1016/j.fluid.2025.114612

René Gómez-Pineda , Ana Soto , Oscar Rodríguez , María del Mar Olaya , Antonio Marcilla

Polyethylene glycol (PEG) 6000, 10,000, or 20,000/sodium citrate Aqueous Two-Phase Systems (ATPS) were characterized at 283.2, 298.2, and 313.2 K. The compositions of the equilibrium phases were determined using an analysis procedure based on density and refractive index measurements. The complete liquid-liquid equilibrium region was obtained up to the point of solid phase precipitation, and the binodal curve was constructed from the endpoints of the experimental tie-lines. The effects of both temperature and polymer molecular weight were analyzed. Furthermore, the entire phase diagram was established using the analysis procedure based on physical property measurements, enabling experimental determination of all singular points that define the solid-liquid, solid-liquid-liquid, and solid-solid-liquid regions. Data correlation for all equilibrium compositions was carried out individually at 283.2 K, where the solid salt was present as a pentahydrate, and simultaneously at 298.2 and 313.2 K, where the salt was dihydrated, using the classical NRTL equation. The model successfully correlated all phase diagrams with standard deviations between experimental and correlated data below 1.6 wt% in all cases.

聚乙二醇（PEG） 6000、10,000或20,000/柠檬酸钠双水相体系（ATPS）在283.2、298.2和313.2 K下进行表征。利用基于密度和折射率测量的分析程序来确定平衡相的组成。在固相析出点处得到了完整的液-液平衡区，并从实验系线端点处构造了双节曲线。分析了温度和聚合物分子量的影响。此外，利用基于物性测量的分析程序建立了整个相图，使实验能够确定定义固-液、固-液-液和固-固-液区域的所有奇异点。所有平衡成分的数据分别在283.2 K时进行了相关性分析，其中固体盐以五水化合物的形式存在，同时在298.2和313.2 K时，盐以二水化合物的形式存在，使用经典NRTL方程。在所有情况下，该模型成功地将所有相图与实验数据和相关数据之间的标准差小于1.6 wt%关联起来。

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引用次数: 0

Phase behavior analysis of multi-component hydrocarbon in shale reservoir multi-scale pore systems using a modified Gibbs ensemble Monte Carlo molecular simulation 基于改进Gibbs系综蒙特卡罗分子模拟的页岩储层多尺度孔隙体系多组分烃相行为分析

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-10-27 DOI: 10.1016/j.fluid.2025.114610

Ran Bi , Zhengdong Lei , Mingqiang Hao , Yong Qin , Fangxuan Chen , Yuewei Pan , Gang Li

Shale resources have been crucial in the production of oil and gas. Over the past few years, the extraction of tight oil and gas has emerged as a major energy source. Shale reservoirs are complex, and understanding hydrocarbon phase behavior is essential for reserve estimation, reservoir simulation, production forecasting, and enhanced oil recovery. In this work, we build a multi-scale system using molecular simulation incorporating nano-scale pores with macro-scale pores to investigate the confinement effect on the phase behavior of reservoir fluids in shale rocks. Comparing with traditional single-scale models, the multi-scale model better mimics the feature (macropores + nanopores) of shale rocks. We simulate the constant composition expansion (CCE) experiment for multi-component hydrocarbon mixtures using the Gibbs ensemble Monte Carlo at imposed pressures (NPT-GEMC) technique to quantify the confinement effect on the saturation pressure and composition alterations of fluids in confined and bulk regions of the multi-scale systems. Our results indicate that due to adsorption in nanopores, there is a notable difference between the compositions of fluids in the bulk region and those in the confined region of the system. For the bubble-point pressure calculations of a methane-ethane binary mixture fluid, the first bubble in the bulk region appears at a higher pressure comparing to the bubble-point pressure of the same initial reservoir fluid in a conventional reservoir. The bubble-point pressure of the methane-ethane mixture increased by 5.8–12.4 % depending on confined volume fraction. For the dew-point pressure calculation of an Eagle Ford gas condensate reservoir fluid, there may exist a reservoir fluid type shift, which can lead to a disappearance of the saturation pressure due to progressive shrinkage of the two-phase envelope.

页岩资源在油气生产中起着至关重要的作用。在过去的几年里，致密油和天然气的开采已经成为一种主要的能源。页岩储层非常复杂，了解油气相行为对于储量估算、储层模拟、产量预测和提高采收率至关重要。本文采用分子模拟的方法，建立了纳米尺度孔隙与宏观尺度孔隙相结合的多尺度系统，研究了页岩储层流体相行为的约束效应。与传统的单尺度模型相比，多尺度模型能更好地模拟页岩的特征（大孔隙+纳米孔隙）。利用Gibbs系综Monte Carlo at强加压力（NPT-GEMC）技术模拟了多组分烃类混合物的恒定组分膨胀（CCE）实验，量化了多尺度体系中约束区和体积区流体的饱和压力和组分变化的约束效应。结果表明，由于纳米孔的吸附作用，体系体积区和密闭区流体的组成存在显著差异。对于甲烷-乙烷二元混合流体的泡点压力计算，与常规储层中相同初始储层流体的泡点压力相比，体积区域的第一个气泡出现的压力更高。随着限制体积分数的增加，甲烷-乙烷混合物的气泡点压力增加了5.8 ~ 12.4%。Eagle Ford凝析气藏流体露点压力计算中，可能存在储层流体类型变化，由于两相包线的递进收缩，导致饱和压力消失。

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引用次数: 0

Phase equilibria and excess enthalpy for tetrahydrofuran + 2-methylpyrazine, tetrahydrofuran + 2-methylpyridine and 2-methylpyridine + 2-methylpyrazine: Experimental measurement and predictive modeling 四氢呋喃+ 2-甲基吡嗪，四氢呋喃+ 2-甲基吡啶和2-甲基吡啶+ 2-甲基吡嗪的相平衡和过量焓：实验测量和预测建模

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-10-21 DOI: 10.1016/j.fluid.2025.114609

Ehsan Asadi, Agung Ari Wibowo, Muhammad Ossama, Petri Uusi-Kyyny, Juha-Pekka Pokki, Ville Alopaeus

Knowledge about the vapor–liquid equilibrium (VLE) behavior of systems containing 2-methylpyridine or 2-methylpyrazine is limited in the literature, despite their industrial importance. In this study, consistent VLE data for mixtures of tetrahydrofuran + 2-methylpyrazine and 2-methylpyridine + 2-methylpyrazine at 50 and 75 kPa, as well as the system of tetrahydrofuran + 2-methylpyridine at 50, 75, and 101 kPa are presented. The excess molar enthalpy (H^E) of these binaries has been measured using an isothermal flow calorimeter at 298.15 K and 101 kPa. The vapor pressure data of the pure components were measured and correlated over the temperature range between 294 and 405 K. The measured VLE and H^E data were successfully correlated with NRTL, UNIQUAC, and Wilson activity coefficient models. In addition, the acquired VLE and H^E were compared with those predicted by COSMO-RS and different predictive group contribution (GC) based models, including the original UNIFAC, UNIFAC-Dortmund, Volume Translated Peng-Robinson (VTPR) and Predictive Soave–Redlich–Kwong (PSRK). A satisfactory agreement was observed between the calculated results and experimental VLE data for all predictive methods; however, these models exhibited lower accuracy in predicting H^E compared to VLE. Attained phase equilibria were checked for thermodynamic consistency using Wisniak’s l-W and Van Ness methods. All binaries exhibit nearly ideal behavior.

关于含有2-甲基吡啶或2-甲基吡嗪的体系的气液平衡（VLE）行为的知识在文献中是有限的，尽管它们在工业上很重要。在本研究中，四氢呋喃+ 2-甲基吡嗪和2-甲基吡啶+ 2-甲基吡嗪在50和75 kPa下的混合物，以及四氢呋喃+ 2-甲基吡啶在50、75和101 kPa下的体系，给出了一致的VLE数据。在298.15 K和101 kPa条件下，用等温流量热计测量了这些二元化合物的过量摩尔焓（HE）。在294 ~ 405 K的温度范围内测量了纯组分的蒸气压数据，并进行了相关分析。测量的VLE和HE数据成功地与NRTL、UNIQUAC和Wilson活度系数模型相关。此外，将获得的VLE和HE与cosmos - rs和不同基于预测组贡献（GC）的模型（包括原始UNIFAC、unifacd - dortmund、Volume translations Peng-Robinson （VTPR）和predictive Soave-Redlich-Kwong (PSRK)）预测的VLE和HE进行比较。所有预测方法的计算结果与实验结果吻合较好；然而，与VLE相比，这些模型在预测HE方面的准确性较低。使用Wisniak的l-W和Van Ness方法检查了所获得的相平衡的热力学一致性。所有二进制都表现出近乎理想的行为。

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引用次数: 0

Modeling liquid-liquid equilibria and aggregate formation in aqueous surfactant solutions 模拟水表面活性剂溶液中的液-液平衡和聚集形成

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-10-21 DOI: 10.1016/j.fluid.2025.114608

Milan Völkel , Gabriele Sadowski

Surfactants exhibit amphiphilic properties that make them particularly interesting for diverse applications in oil recovery, pharmaceutical development and membrane science. Above a critical micelle concentration (CMC), surfactants form aggregates, which is a key feature that allows for the solubilization of hydrophobic molecules in aqueous solutions. This study introduces a novel framework that integrates PC-SAFT into an Aggregate Formation Model (AFM) to describe and predict aggregation phenomena and liquid-liquid equilibria (LLE) in both diluted and concentrated aqueous surfactant solutions. We simultaneously consider the equilibrium between surfactant monomers and their aggregates on the one hand and the equilibrium between two coexisting aqueous micellar phases on the other hand. Unlike most previous models which are limited to diluted concentrations, our approach explicitly also accounts for both aggregate-aggregate interactions and aggregate-solvent interactions. This is achieved by treating surfactant aggregates as distinct species differing from their corresponding monomers. For that purpose, we employed a polymer-like representation of surfactant aggregates allowing for their characterization by aggregate repeat units. This methodology was successfully validated across 12 surfactants from the polyoxyethylene alkyl ether (C_iE_j) class. Our approach provides almost quantitative modeling results of CMCs, LLE curves, as well as average aggregation numbers in the two coexisting phases.

表面活性剂具有两亲性，这使得它们在石油开采、药物开发和膜科学等领域的应用特别有趣。在临界胶束浓度（CMC）以上，表面活性剂形成聚集体，这是允许疏水分子在水溶液中增溶的关键特征。本研究引入了一个新的框架，将PC-SAFT集成到聚集体形成模型（AFM）中，以描述和预测稀释和浓缩水表面活性剂溶液中的聚集现象和液-液平衡（LLE）。我们同时考虑了表面活性剂单体及其聚集体之间的平衡和两种共存的水胶束相之间的平衡。不像大多数以前的模型仅限于稀释浓度，我们的方法也明确地说明了集合体-集合体相互作用和集合体-溶剂相互作用。这是通过将表面活性剂聚集体视为不同于其相应单体的不同物种来实现的。为此，我们采用了表面活性剂聚集体的聚合物样表示，允许通过聚集体重复单元对其进行表征。该方法在聚氧乙烯烷基醚（CiEj）类的12种表面活性剂上成功验证。我们的方法提供了几乎定量的cmc、LLE曲线的建模结果，以及两个共存阶段的平均聚集数。

{"title":"Modeling liquid-liquid equilibria and aggregate formation in aqueous surfactant solutions","authors":"Milan Völkel , Gabriele Sadowski","doi":"10.1016/j.fluid.2025.114608","DOIUrl":"10.1016/j.fluid.2025.114608","url":null,"abstract":"<div><div>Surfactants exhibit amphiphilic properties that make them particularly interesting for diverse applications in oil recovery, pharmaceutical development and membrane science. Above a critical micelle concentration (CMC), surfactants form aggregates, which is a key feature that allows for the solubilization of hydrophobic molecules in aqueous solutions. This study introduces a novel framework that integrates PC-SAFT into an Aggregate Formation Model (AFM) to describe and predict aggregation phenomena and liquid-liquid equilibria (LLE) in both diluted and concentrated aqueous surfactant solutions. We simultaneously consider the equilibrium between surfactant monomers and their aggregates on the one hand and the equilibrium between two coexisting aqueous micellar phases on the other hand. Unlike most previous models which are limited to diluted concentrations, our approach explicitly also accounts for both aggregate-aggregate interactions and aggregate-solvent interactions. This is achieved by treating surfactant aggregates as distinct species differing from their corresponding monomers. For that purpose, we employed a polymer-like representation of surfactant aggregates allowing for their characterization by aggregate repeat units. This methodology was successfully validated across 12 surfactants from the polyoxyethylene alkyl ether (C<sub>i</sub>E<sub>j</sub>) class. Our approach provides almost quantitative modeling results of CMCs, LLE curves, as well as average aggregation numbers in the two coexisting phases.</div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"602 ","pages":"Article 114608"},"PeriodicalIF":2.7,"publicationDate":"2025-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145569110","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

Volumetric and viscosity data of 1-iodonaphthalene + n-alkane mixtures at (288.15-308.15) K 1-碘萘+正构烷烃混合物在（288.15-308.15）K下的体积和粘度数据

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-10-15 DOI: 10.1016/j.fluid.2025.114607

Luis Felipe Sanz, Juan Antonio González, Fernando Hevia, Daniel Lozano-Martín, João Victor Alves-Laurentino, Fatemeh Pazoki, Isaías. García de la Fuente, José Carlos Cobos

Density and viscosity measurements have been performed for the systems 1-iodonaphthalene + heptane, or + decane, or + dodecane, or + tetradecane over the temperature range (288.15-308.15) K and at 94 kPa. At this end, a densitometer Anton-Paar DMA 602 and a Ubbelohde viscosimeter were used. Excess molar volumes (

V_{m}^{E}

) are large and negative and decrease when the temperature is increased, which reveals that the main contribution to

V_{m}^{E}

arises from structural effects. The values of the deviations of dynamic viscosity from linear dependence on mole fraction are also large and negative, indicating that n-alkanes are good breakers of the interactions between 1-iodonaphthalene molecules. Different models were applied for describing viscosity data. The McAllister’s equation correlates well kinematic viscosities. Results are similar when dynamic viscosities (

η

) are correlated with the Grunberg-Nissan or Fang-He equations. This means that size effects are not relevant on the mentioned data. The adjustable parameter of the Grunberg-Nissan equation is negative for all the systems at any temperature, a typical feature of systems where dispersive interactions are dominant. This is in agreement with findings obtained in previous studies on similar n-alkane mixtures involving C₆H₅X (X = Cl, Br, I) or 1,2,4-trichlorobenzene or 1-chloronaphthalene. Free volume effects have little influence on the present

η

results, well represented by the absolute rate model using residual molar Gibbs energies obtained from the DISQUAC model.

在温度范围（288.15-308.15）K和94 kPa下，对1-碘萘+庚烷、+癸烷、+十二烷或+十四烷体系进行了密度和粘度测量。为此，使用了密度计Anton-Paar DMA 602和Ubbelohde粘度计。过量摩尔体积（VmE）较大且为负值，随着温度的升高而减小，这表明VmE的主要贡献来自于结构效应。动态粘度与摩尔分数线性关系的偏差值也较大且为负值，表明正构烷烃是1-碘萘分子间相互作用的良好破坏者。采用不同的模型来描述粘度数据。麦卡利斯特方程与运动粘度关系良好。当动态粘度（η）与Grunberg-Nissan或Fang-He方程相关时，结果相似。这意味着大小效应与上述数据无关。在任何温度下，Grunberg-Nissan方程的可调参数对所有系统都是负的，这是色散相互作用占主导地位的系统的典型特征。这与先前对含有C6H5X （X = Cl, Br， I）或1,2,4-三氯苯或1-氯萘的类似正构烷烃混合物的研究结果一致。自由体积效应对η结果的影响不大，用DISQUAC模型得到的残余摩尔吉布斯能的绝对速率模型很好地表示了自由体积效应。

{"title":"Volumetric and viscosity data of 1-iodonaphthalene + n-alkane mixtures at (288.15-308.15) K","authors":"Luis Felipe Sanz, Juan Antonio González, Fernando Hevia, Daniel Lozano-Martín, João Victor Alves-Laurentino, Fatemeh Pazoki, Isaías. García de la Fuente, José Carlos Cobos","doi":"10.1016/j.fluid.2025.114607","DOIUrl":"10.1016/j.fluid.2025.114607","url":null,"abstract":"<div><div>Density and viscosity measurements have been performed for the systems 1-iodonaphthalene + heptane, or + decane, or + dodecane, or + tetradecane over the temperature range (288.15-308.15) K and at 94 kPa. At this end, a densitometer Anton-Paar DMA 602 and a Ubbelohde viscosimeter were used. Excess molar volumes (<span><math><msubsup><mi>V</mi><mrow><mi>m</mi></mrow><mi>E</mi></msubsup></math></span>) are large and negative and decrease when the temperature is increased, which reveals that the main contribution to <span><math><msubsup><mi>V</mi><mrow><mi>m</mi></mrow><mi>E</mi></msubsup></math></span>arises from structural effects. The values of the deviations of dynamic viscosity from linear dependence on mole fraction are also large and negative, indicating that <em>n</em>-alkanes are good breakers of the interactions between 1-iodonaphthalene molecules. Different models were applied for describing viscosity data. The McAllister’s equation correlates well kinematic viscosities. Results are similar when dynamic viscosities (<span><math><mi>η</mi></math></span>) are correlated with the Grunberg-Nissan or Fang-He equations. This means that size effects are not relevant on the mentioned data. The adjustable parameter of the Grunberg-Nissan equation is negative for all the systems at any temperature, a typical feature of systems where dispersive interactions are dominant. This is in agreement with findings obtained in previous studies on similar <em>n</em>-alkane mixtures involving C<sub>6</sub>H<sub>5</sub>X (X = Cl, Br, I) or 1,2,4-trichlorobenzene or 1-chloronaphthalene. Free volume effects have little influence on the present <span><math><mi>η</mi></math></span>results, well represented by the absolute rate model using residual molar Gibbs energies obtained from the DISQUAC model<strong>.</strong></div></div>","PeriodicalId":12170,"journal":{"name":"Fluid Phase Equilibria","volume":"602 ","pages":"Article 114607"},"PeriodicalIF":2.7,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145340697","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

Application of COSMO screening to extractive distillation of true lavender essential oil using ionic liquids: An experimental and quantum chemical study COSMO筛选在离子液体萃取蒸馏真薰衣草精油中的应用：实验和量子化学研究

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-10-11 DOI: 10.1016/j.fluid.2025.114606

Xinyue Lin , Dezhi Cao , Jian Hong, Dingkai Hu, Biao Liu, Xinpeng Bi, Qiang Wang

Separating heat-sensitive components such as Linalool in lavender essential oil is difficult. Traditional techniques have high energy consumption and are prone to component degradation. This paper presents an efficient method of separating the main components (Linalool, Linalyl Acetate and α-Terpineol) of lavender essential oil using decompression distillation combined with ionic liquids (ILs) extraction. Optimising the parameters of decompression distillation (pressure 5.5 kPa, full reflux for 0.5 h, reflux ratio 6) resulted in Linalool and Linalyl Acetate purities of 75.21 % and 59.39 %, respectively—wherein the purity and yield of Linalool were measured in the distillate stream, while those of Linalyl Acetate were determined in the bottoms stream. Using the conductor-like screening model for segment activity coefficient (COSMO-SAC), 1‑butyl‑4-methylpyridinium bis (trifluoromethanesulfonyl) imide ([BMPY][NTf₂]) was identified as the optimal extractant. Adding 1 wt% of this compound increased the purity of Linalyl Acetate to 81%. Adding 1 wt% increased the purity of Linalyl Acetate to 81.34 %, with a yield of 61.89 %. Quantum chemical analysis showed that [BMPY][NTf₂] bound to α-Terpineol via strong hydrogen bonding and that Linalyl Acetate could be more easily separated from the top of the column due to its low polarity. This study provides a green, feasible technical solution for efficiently separating thermosensitive essential oils, and establishes a theoretical foundation for applying ILs to separate complex mixtures.

分离薰衣草精油中的热敏感成分如芳樟醇是困难的。传统技术能耗高，且容易导致部件退化。本文提出了减压蒸馏结合离子液体萃取分离薰衣草精油中主要成分（芳樟醇、醋酸芳樟醇和α-松油醇）的有效方法。优化减压蒸馏参数（压力5.5 kPa，全回流0.5 h，回流比6），得到的芳樟醇和乙酸芳樟醇的纯度分别为75.21%和59.39%，其中芳樟醇的纯度和得率在蒸馏流中测定，乙酸芳樟醇的纯度和得率在底流中测定。采用类导体筛选段活度系数模型（cosmoo - sac），确定1 -丁基- 4-甲基吡啶双（三氟甲磺酰基）亚胺（[BMPY][NTf2]）为最佳萃取剂。添加1 wt%的该化合物可使乙酸芳樟醇的纯度提高到81%。添加1 wt%可使乙酸芳樟醇纯度达到81.34%，收率为61.89%。量子化学分析表明，[BMPY][NTf2]通过强氢键与α-松油醇结合，而乙酸芳樟醇的极性较低，更容易从色谱柱顶部分离。本研究为高效分离热敏性精油提供了一种绿色可行的技术方案，为热敏性精油在复杂混合物分离中的应用奠定了理论基础。

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引用次数: 0

Experimental study and MD simulation of neutral choline–based deep eutectic solvents regulated by ethanol 乙醇调节的中性胆碱基深共晶溶剂的实验研究及MD模拟

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-10-08 DOI: 10.1016/j.fluid.2025.114605

Huanhuan Hu , Linyun Luo , Zhongyuan Liu , Lin Tian , Guanjia Zhao

This study focuses on deep eutectic solvent (DES) systems composed of choline chloride and four alcohol-based hydrogen bond donors (glycerol, 1,3-propylene glycol, 1,2-propylene glycol, and 2,3-butylene glycol), with ethanol added at mole fractions ranging from 0 to 1. Experimental measurements of density and viscosity were conducted, and the results were validated using molecular dynamics (MD) simulations based on the GAFF force field and RESP2 charge model. The simulation results closely matched the experimental data, confirming the accuracy of the modeling approach. Radial distribution function and hydrogen bond analyses revealed that ethanol disrupts hydrogen bonds formed between the choline cation (CHO⁺) and the anion (Cl⁻), between the anion (Cl⁻) and the hydrogen bond donor (HBD), and among HBD molecules themselves. Instead, ethanol forms weaker new bonds with CHO⁺, Cl⁻, and HBD. Consequently, at ethanol mass fractions of 49 %, 53 %, 43 %, and 40 % in the four systems, viscosity decreased by 96 %, 88 %, 93 %, and 93 %, respectively. Despite these changes, the overall DES hydrogen bond network remained largely intact. These findings demonstrate that ethanol effectively tunes the microstructure and viscosity of DESs, enhancing their potential for practical applications.

本研究的重点是由氯化胆碱和四种醇基氢键供体（甘油、1,3-丙二醇、1,2-丙二醇和2,3-丁二醇）组成的深共晶溶剂（DES）体系，并以摩尔分数0到1加入乙醇。实验测量了密度和粘度，并利用基于GAFF力场和RESP2电荷模型的分子动力学（MD）模拟验证了结果。仿真结果与实验数据吻合较好，验证了建模方法的准确性。径向分布函数和氢键分析表明，乙醇破坏了胆碱阳离子（CHO+）与阴离子（Cl−）、阴离子（Cl−）与氢键供体（HBD）以及HBD分子之间形成的氢键。相反，乙醇与CHO+、Cl−和HBD形成较弱的新键。因此，在四种体系中，当乙醇质量分数分别为49%、53%、43%和40%时，粘度分别降低了96%、88%、93%和93%。尽管有这些变化，整个DES氢键网络基本保持不变。这些发现表明，乙醇有效地调节了DESs的微观结构和粘度，增强了它们的实际应用潜力。

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引用次数: 0

Hydrate equilibrium of carbon dioxide in aqueous solutions of 1,4-cyclohexanedione as a thermodynamic inhibitor 作为热力学抑制剂的1,4-环己二酮水溶液中二氧化碳的水合物平衡

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-10-06 DOI: 10.1016/j.fluid.2025.114604

Xinrui Hou, Zhigao Sun

In oil and gas transportation pipelines, hydrate formation brings serious pipeline blockage risk. Injecting thermodynamic hydrate inhibitors will prohibit hydrate formation. The effect of 1,4-cyclohexanedione as a thermodynamic inhibitor on hydrate equilibrium conditions of CO₂ was studied using isochoric stepwise heating method. The experimental results show that 1,4-cyclohexanedione can inhibit hydrate formation of CO₂. Aqueous solutions with 1,4-cyclohexanedione effectively moves the equilibrium boundary to the direction of lower temperatures and higher pressures. The testing data also show that CO₂ hydrate equilibrium pressures increased more when the concentration of 1,4-cyclohexanedione increased. The temperature shift reaches 2.05 K at 2.57 MPa by adding 15 wt % CHD. The inhibitory effect of CHD on carbon dioxide hydrate formation is similar to that of n-ethyl-n-methylmorpholinium bromide and tetramethyl ammonium chloride.

在油气输送管道中，水合物的形成带来了严重的管道堵塞风险。注入热力学水合物抑制剂将阻止水合物的形成。采用等共阶加热法研究了1,4-环己二酮作为热力学抑制剂对CO2水合物平衡条件的影响。实验结果表明，1,4-环己二酮能抑制CO2的水合物生成。含有1,4-环己二酮的水溶液有效地将平衡边界向低温高压方向移动。测试数据还表明，随着1,4-环己二酮浓度的增加，CO2水合物平衡压力增加更多。加入15%的CHD，在2.57 MPa下，温度变化达到2.05 K。CHD对二氧化碳水合物形成的抑制作用类似于n-乙基-n-甲基溴化铵和四甲基氯化铵。

引用次数: 0

Corrigendum to “Enhancing swelling kinetics of pNIPAM lyogels: The role of crosslinking, copolymerization, and solvent” [Fluid Phase Equilibria 597 (2025) 114462] “增强pNIPAM凝胶的溶胀动力学：交联、共聚和溶剂的作用”[流体相平衡597(2025)114462]的勘误

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-10-06 DOI: 10.1016/j.fluid.2025.114593

Kathrin Marina Eckert , Jelisa Bonsen , Anja Hajnal , Johannes Gmeiner , Jonah Hasse , Muhammad Adrian , Julian Karsten , Patrick A. Kißling , Alexander Penn , Bodo Fiedler , Gerrit A. Luinstra , Irina Smirnova

引用次数: 0