Fluid Phase Equilibria最新文献_第7页

A guideline on determining Langmuir constants in van der Waals-Platteeuw model for gas hydrate equilibrium calculations 天然气水合物平衡计算中范德华-普拉提模型中Langmuir常数的确定指南

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.2025.114603

Xin Chen , Benbiao Li

The van der Waals-Platteeuw (vdW-P) model employs the Langmuir constants to distinguish the ability of guest gases for forming hydrates. The selections of the equations of states (EOSs) and Kihara potential theories play critical roles in the determinations of Langmuir constants. Hence, this study would combine the Soave-Redlich-Kwong (S-R-K), Peng-Robinson (P-R) and perturbed-chain statistical associating fluid theory (PC-SAFT) EOSs with the single-shell, triple-shell and multi-layered potential theories, respectively, and investigate their effects on the vdW-P model parameter optimizations and hydrate equilibrium calculations. Based on the results for reproducing the gas-mixture and pure-gas hydrate equilibria, the P-R EOS and single-shell potential theory are more recommended to be used in the vdW-P model. Besides, the sensitive analyses revealed that the wrong combinations of vdW-P model parameters with incompatible EOSs and Kihara potential theories led to high calculation errors or even non-convergence issues for predicting hydrate equilibria. Finally, a series of simplified correlations for calculating Langmuir constants have been updated. It is hoped that this study works as a guideline on the proper usage of vdW-P model and the precise predictions of the gas hydrate equilibria.

范德华-普拉特（vdW-P）模型采用朗缪尔常数来区分客体气体形成水合物的能力。状态方程（eos）和Kihara势理论的选择在确定Langmuir常数中起着至关重要的作用。因此，本研究将sove - redlich - kwong （S-R-K）、Peng-Robinson （P-R）和微动链统计关联流体理论（PC-SAFT） eos分别与单壳层、三壳层和多层势理论相结合，研究它们对vdW-P模型参数优化和水合物平衡计算的影响。基于混合气和纯气水合物平衡的再现结果，建议在vdW-P模型中使用P-R方程和单壳势理论。此外，敏感性分析表明，vdW-P模型参数与不相容的eos和Kihara势理论的错误组合导致水合物平衡预测的计算误差很大，甚至出现不收敛问题。最后，更新了计算朗缪尔常数的一系列简化关系式。希望本研究对正确使用vdW-P模型和准确预测天然气水合物平衡具有指导意义。

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引用次数: 0

Experimental measurement and thermodynamic modeling for the methane + methanol binary system: volumetric behavior and Joule-Thomson coefficient modeling 甲烷+甲醇二元体系的实验测量和热力学建模：体积行为和焦耳-汤姆逊系数建模

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-10-03 DOI: 10.1016/j.fluid.2025.114600

Moacir Frutuoso Leal da Costa, Lucas Henrique Gomes de Medeiros, Davi Cezar do Nascimento, Vinicius de Oliveira Souza, Filipe Xavier Feitosa, Hosiberto Batista de Sant’Ana

To address the critical role of the Joule-Thomson (JT) effect in flow assurance for the oil and gas industry, this work presents experimental density data for methane + methanol mixtures at temperatures ranging from 313.15 K to 413.15 K and pressures up to 100 MPa. Using this data, derivative properties such as isothermal compressibility, isobaric expansivity, and Joule-Thomson coefficient were calculated via a correlative Tammann-Tait Eq. and compared against predictions using the PC-SAFT Eq. of state. The results showed that

μ_{J T}

was negative under these conditions, indicating a warming effect upon expansion. The use of the PC-SAFT Eq. was satisfactory, given the system’s complexity, for density data and for properties that did not rely on the isobaric heat capacity. Additionally, a new binary interaction parameter for the methane/methanol pair was obtained and evaluated using the PC-SAFT Eq. of state.

为了解决焦耳-汤姆逊（JT）效应在油气行业流动保障中的关键作用，本研究提供了甲烷+甲醇混合物在温度范围为313.15 K至413.15 K，压力高达100 MPa时的实验密度数据。利用这些数据，通过相关的Tammann-Tait方程计算了等温压缩率、等压膨胀率和焦耳-汤姆森系数等导数性质，并与PC-SAFT状态方程的预测结果进行了比较。结果表明，在此条件下μJT为负，说明膨胀过程中存在升温效应。考虑到系统的复杂性，对于密度数据和不依赖于等压热容的性质，PC-SAFT方程的使用令人满意。此外，利用PC-SAFT状态方程，得到了甲烷/甲醇二元相互作用的新参数。

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引用次数: 0

Bubble point pressures of mixtures containing dimethyl ether or propane, chloroform, and ethanol: Experimental data and modelling 含有二甲醚或丙烷、氯仿和乙醇的混合物的泡点压力：实验数据和模型

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-10-01 DOI: 10.1016/j.fluid.2025.114601

Tomoya Tsuji , Daigo Yokoi , Hiroaki Matsukawa , Taka-aki Hoshina , Hiroyuki Matsuda , Katsumi Tochigi

Chloroform - alcohol mixtures are used as extraction solvents for lipids. In this study, a novel highly volatile solvent was proposed based on pressurizing a chloroform–alcohol mixture using either dimethyl ether or propane. A static apparatus was used to measure the bubble point pressures of three binaries: dimethyl ether–chloroform and dimethyl ether–ethanol at (283.15–313.15) K and propane – chloroform at 313.15 K. Equimolar chloroform–ethanol mixtures were used to measure the bubble point pressures of two ternary systems at 313.15 K: dimethyl ether–chloroform–ethanol and propane–chloroform–ethanol. The data for the aforementioned binaries and the other constituent binaries of the ternaries, propane–ethanol at (293.15–313.2) K and chloroform–ethanol at (308–328) K, were correlated with four activity coefficient models: Wilson, T-K-Wilson, NRTL and UNIQUAC. The best reproducibility among the four models was obtained for the NRTL equation. The experimental ternary data were compared with NRTL predictions obtained using only binary parameters. The average values of the absolute relative deviations for the pressure were 5.37 % for dimethyl ether – chloroform – ethanol and 3.09 % for propane – chloroform – ethanol. The predicted VLE diagram was used to estimate the mole fractions of dimethyl ether or propane needed to pressurize an equimolar liquid mixture of chloroform–ethanol such that rapid vaporization would occur upon exposure to atmospheric pressure.

氯仿-酒精混合物被用作提取脂质的溶剂。在这项研究中，提出了一种新的高挥发性溶剂，该溶剂基于二甲醚或丙烷加压氯仿-酒精混合物。用静态仪器测量了二甲醚-氯仿和二甲醚-乙醇在（283.15 ~ 313.15）K和丙烷-氯仿在313.15 K下的泡点压力。采用等摩尔氯仿-乙醇混合物测定了313.15 K时二甲醚-氯仿-乙醇和丙烷-氯仿-乙醇两种三元体系的泡点压力。上述二元化合物以及三元化合物的其他组成二元化合物（293.15-313.2）K丙烷-乙醇和（308-328）K氯仿-乙醇的数据均与威尔森、t -K-威尔森、NRTL和UNIQUAC四种活度系数模型相关。4种模型中NRTL方程的重现性最好。将实验三元数据与仅使用二元参数得到的NRTL预测结果进行了比较。二甲醚-氯仿-乙醇的压力绝对相对偏差平均值为5.37%，丙烷-氯仿-乙醇的压力绝对相对偏差平均值为3.09%。预测的VLE图用于估计二甲醚或丙烷的摩尔分数，以加压等摩尔氯仿-乙醇液体混合物，使其在暴露于大气压下会发生快速汽化。

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引用次数: 0

Corrigendum to “Exploring pNIPAM lyogels: Experimental study on swelling equilibria in various organic solvents and mixtures, supported by COSMO-RS analysis” [Fluid Phase Equilibria 586 (2024) 114182] “探索pNIPAM lyogels：在各种有机溶剂和混合物中膨胀平衡的实验研究，由cosmos - rs分析支持”的勘勘表[流体相平衡586 (2024)114182]

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-10-01 DOI: 10.1016/j.fluid.2025.114594

Kathrin Marina Eckert , Simon Müller , Gerrit A. Luinstra , Irina Smirnova

引用次数: 0

Redistribution of hydrocarbon and water within graphene mesopores under an external electric field: Evidences from molecular dynamics simulations 外电场下石墨烯介孔内碳氢化合物和水的再分配：来自分子动力学模拟的证据

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-09-30 DOI: 10.1016/j.fluid.2025.114596

Flávia N. Braga, Felipe M. Coelho, Loreena Y. Pinotti, Gustavo Doubek, Luís F.M. Franco

The behavior of confined fluids under external electric fields is central to the development of field-responsive technologies in catalysis and separations. Here, we use Molecular Dynamics simulations to explore the structural response of water–hydrocarbon mixtures (methane,

n

-butane, and

n

-pentane) confined within graphene slit pores, subjected to electric field strengths ranging from 1.5 to 7.5 V

{nm}^{- 1}

. In the absence of an electric field, the system exhibits clear phase separation along the confinement axis, with hydrocarbons preferentially adsorbed near the graphene walls and water localized at the center. As the electric field increases, this organization becomes disrupted, with a lateral redistribution of water molecules and reduced interfacial definition. The spatial rearrangement is confirmed through density profiles along multiple axes, while analysis of the order parameter indicates negligible dipolar alignment of water molecules. Dielectric permittivity calculations reveal anisotropic polarization responses, supporting a mechanism dominated by positional, rather than orientational, field effects. The observed redistribution is significant above 3.0 V

{nm}^{- 1}

and intensifies with stronger fields. These results provide molecular-level insights into the design of nanoconfined systems where electric fields are used to modulate fluid organization. Implications are far-reaching: in electric swing adsorption (ESA), field-induced redistribution offers new levers for controlling selectivity and regeneration; in electrostatic catalysis, particularly Fischer–Tropsch synthesis (FTS), dynamic positioning of polar intermediates such as CO and H₂O near catalytic surfaces could fine-tune reaction pathways and improve selectivity. Overall, this work provides a foundational framework for designing electric-field-responsive nanoconfined systems relevant to gas separations and catalytic processes.

外加电场作用下受限流体的行为是催化和分离领域场响应技术发展的核心。在这里，我们使用分子动力学模拟来研究限制在石墨烯狭缝孔内的水-烃混合物（甲烷、正丁烷和正戊烷）在1.5到7.5 Vnm−1的电场强度下的结构响应。在没有电场的情况下，该体系沿着约束轴表现出明显的相分离，碳氢化合物优先吸附在石墨烯壁附近，而水则集中在中心。随着电场的增加，这种组织被破坏，水分子的横向重新分配和界面清晰度降低。通过沿多轴的密度分布证实了空间重排，而序参量分析表明水分子的偶极排列可以忽略不计。介质介电常数计算揭示了各向异性极化响应，支持由位置而不是方向场效应主导的机制。在3.0 Vnm−1以上观测到的重分布是显著的，并且随着电场的增强而增强。这些结果为纳米限制系统的设计提供了分子水平的见解，其中电场用于调节流体组织。影响深远：在电振荡吸附（ESA）中，电场诱导的再分配为控制选择性和再生提供了新的杠杆；在静电催化，特别是费托合成（FTS）中，CO和H2O等极性中间体在催化表面附近的动态定位可以微调反应途径并提高选择性。总的来说，这项工作为设计与气体分离和催化过程相关的电场响应纳米限制系统提供了一个基础框架。

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引用次数: 0

The solubility of O-methylphenylacetic acid (OMPA) in different pure solvents, corrections and thermodynamic properties 邻甲基苯基乙酸（OMPA）在不同纯溶剂中的溶解度、修正和热力学性质

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-09-30 DOI: 10.1016/j.fluid.2025.114602

Rou Zhang , Fanfan Li , Yazhou Li , Xingchuan Yang , Chunmei Cao , Li Xu , Yi Yu

This study investigated the dissolution behavior of O-methylphenylacetic acid (OMPA) in twelve organic solvent systems (methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, acetone, acetonitrile, dichloromethane, 1,2-dichloroethane, methyl acetate, ethyl acetate) across eight temperature gradients. The solubility of all tested solvents increased with temperature, and acetone exhibited the highest solubility among them. A multidimensional research approach was employed to elucidate the mechanisms underlying the dissolution process. This approach integrated molecular electrostatic potential surface (MEPS) analysis, the interpretation of solvent physicochemical parameters, and density functional theory (DFT) calculations. Six thermodynamic models (λh, modified Apelblat, van't Hoff, Yaws, Wilson, and Jouyban models) were applied to correlate the regularity of solubility evolution. The validity of these models was evaluated through ARD and RMSD. Among these models examined, the Yaws model demonstrated optimal fitting performance with a 100ARD average of 0.8221. Additionally, thermodynamic analysis revealed patterns concerning changes in the apparent mixed Gibbs free energy (Δ_solG), the apparent mixing enthalpy change (Δ_solH), and the apparent mixing entropy change (Δ_solS) throughout the dissolution process. It was observed that the dissolution of OMPA is endothermic and driven by an increase in entropy.

研究了邻甲基苯基乙酸（OMPA）在12种有机溶剂体系（甲醇、乙醇、正丙醇、正丙醇、正丁醇、正丁醇、正丁醇、丙酮、乙腈、二氯甲烷、1,2-二氯乙烷、乙酸甲酯、乙酸乙酯）中8个温度梯度下的溶解行为。溶剂的溶解度随温度升高而升高，其中丙酮的溶解度最高。采用多维研究方法来阐明溶解过程的机制。该方法集成了分子静电电位表面（MEPS）分析、溶剂理化参数解释和密度泛函理论（DFT）计算。采用λh、修正Apelblat、van't Hoff、Yaws、Wilson和Jouyban模型分析了溶解度演化规律。通过ARD和RMSD评价模型的有效性。其中，雅司模型拟合效果最佳，100ARD平均值为0.8221。此外，热力学分析揭示了溶解过程中表观混合吉布斯自由能（ΔsolG）、表观混合焓变（ΔsolH）和表观混合熵变（ΔsolS）的变化规律。观察到OMPA的溶解是吸热的，由熵的增加驱动。

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引用次数: 0

Data-driven extended corresponding state approach for residual property prediction of hydrofluoroolefins 数据驱动的扩展对应态法用于氢氟烯烃剩余物性预测

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-09-27 DOI: 10.1016/j.fluid.2025.114599

Gang Wang, Peng Hu

Hydrofluoroolefins are considered the most promising next-generation refrigerants due to their extremely low global warming potential values, which can effectively mitigate the global warming effect. However, the lack of reliable thermodynamic data hinders the discovery and application of newer and superior hydrofluoroolefin refrigerants. In this work, integrating the strengths of theoretical method and data-driven method, we proposed a neural network extended corresponding state model to predict the residual thermodynamic properties of hydrofluoroolefin refrigerants. The innovation is that the fluids are characterized through their microscopic molecular structures by the inclusion of graph neural network module and the specialized design of model architecture to enhance its generalization ability. The proposed model is trained using the highly accurate data of available known fluids, and evaluated via the leave-one-out cross-validation method. Compared to conventional extended corresponding state models or cubic equation of state, the proposed model shows significantly improved accuracy for density and energy properties in liquid and supercritical regions, with average absolute deviation of 1.49 % (liquid) and 2.42 % (supercritical) for density, 3.37 % and 2.50 % for residual entropy, 1.85 % and 1.34 % for residual enthalpy. These results demonstrate the effectiveness of embedding physics knowledge into the machine learning model. The proposed neural network extended corresponding state model is expected to significantly accelerate the discovery of novel hydrofluoroolefin refrigerants.

氢氟烯烃因其极低的全球变暖潜能值而被认为是最有前途的下一代制冷剂，可以有效地缓解全球变暖效应。然而，缺乏可靠的热力学数据阻碍了更新和更好的氢氟烯烃制冷剂的发现和应用。本文结合理论方法和数据驱动方法的优势，提出了一种神经网络扩展的对应状态模型来预测氢氟烯烃制冷剂的剩余热力学性质。创新之处在于，通过引入图神经网络模块和模型架构的专业化设计，通过微观分子结构来表征流体，增强了模型的泛化能力。该模型使用已知流体的高精度数据进行训练，并通过留一交叉验证方法进行评估。与传统的扩展对应状态模型或三次状态方程相比，该模型对液体和超临界区域的密度和能量特性的平均绝对偏差显著提高，密度（液体）和能量特性的平均绝对偏差为1.49%（液体）和2.42%（超临界），剩余熵的平均绝对偏差为3.37%和2.50%，剩余焓的平均绝对偏差为1.85%和1.34%。这些结果证明了将物理知识嵌入到机器学习模型中的有效性。所提出的神经网络扩展对应状态模型有望显著加快新型氢氟烯烃制冷剂的发现。

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引用次数: 0

Partial molar properties for the viscous flow of binary aqueous amine mixtures 二元水胺混合物粘性流动的部分摩尔性质

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-09-25 DOI: 10.1016/j.fluid.2025.114597

Sumudu Karunarathne , Parham Bakhtavar , Lars Erik Øi

Previously reported measured density and viscosities of Monoethanolamine (MEA) + H₂O, N-methyldiethanolamine (MDEA) + H₂O, Dimethylethanolamine (DMEA) +H₂O, and Diethylethanolamine (DEEA) +H₂O mixtures were used to calculate different properties of free energy of activation for viscous flow

Δ G^{*}

, excess free energy of activation for viscous flow

Δ G^{* E}

and partial molar free energy of activation for viscous flow of the components in the mixture

Δ {\bar{G}}_{i}^{*}

from Eyring’s viscosity model. Redlich-Kister polynomial equations were used to represent

Δ G^{* E}

and calculate

Δ {\bar{G}}_{i}^{*}

at different temperatures and amine mole fractions. The behaviour of calculated

Δ {\bar{G}}_{i}^{*}

for amines and H₂O in different mixtures was discussed. The behaviour of reported partial molar volumes

Δ {\bar{V}}_{i}

from our previous work was compared with

Δ {\bar{G}}_{i}^{*}

to identify any similarities for these particular mixtures.

利用先前报道的单乙醇胺(MEA) +H2O、n -甲基二乙醇胺(MDEA) +H2O、二甲基乙醇胺(DMEA) +H2O和二乙基乙醇胺(DEEA) +H2O混合物的密度和粘度，从Eyring的粘度模型中计算黏性流动自由活化能ΔG*、黏性流动多余自由活化能ΔG*E和混合物中各组分黏性流动部分摩尔自由活化能ΔG¯i*的不同性质。用Redlich-Kister多项式方程表示ΔG*E，计算不同温度和胺摩尔分数下的ΔG¯i*。讨论了计算得到的ΔG¯i*对胺和水在不同混合物中的行为。我们将先前工作中报告的偏摩尔体积ΔV¯i的行为与ΔG¯i*进行比较，以确定这些特定混合物的相似性。

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引用次数: 0

A MD simulation study on the influence of pressure on sodium crystal melting 压力对钠晶体熔化影响的MD模拟研究

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-09-25 DOI: 10.1016/j.fluid.2025.114598

Tingting Ma , Tongtong Liu , Yang Li , Baiheng Jing , Panrong Wu , Qinglin Cheng

The molecular dynamics (MD) method and EAM/FS potential are used to study the influence of pressure (1 kPa ∼ 500 MPa) on the non-equilibrium melting process of alkali metal sodium crystals. The changes in macroscopic physical parameters such as potential energy, volume, and heat capacity (C_p) with pressure are obtained, and the evolutions of atomic clusters during the melting process are analyzed by RDF and PTM methods. The non-equilibrium melting temperature (T'_m) and melting time (Δt_m) under different pressures are gotten by macroscopic physical parameters analysis. The pressure has a significant impact on the melting behavior of sodium, particularly at pressures below 150 MPa. The T'_m increases with the increase of pressure, ranging from 423 K to 464 K within the pressure range of 1 kPa to 500 MPa, which is consistent with the experimental data. Besides, the Δt_m first decreases and then increases with increasing pressure, and the shortest melting time is 7.6 ps at 90 MPa. Both RDF analysis and PTM analysis can describe the phase transition process of sodium melting, and also indicate that T'_m increases with increasing pressure. The PTM analysis method can effectively study the transformation of different sodium atom clusters (BCC, HCP, FCC, and Other clusters) during the sodium melting process. It is found that as the temperature increased, some BCC clusters directly transform into Other clusters, while the others first transform into intermediate FCC and HCP clusters, and then into Other clusters. The range of T'_m of sodium is determined to be 425 K ∼ 467 K using PTM analysis method, which is consistent with the results of C_p analysis. There is a good correspondence between the changes in macroscopic physical parameters and the evolution of the atomic clusters during the melting process of sodium crystals. Both of these changes can reveal the melting process of sodium. The thermodynamic parameters related to sodium melting obtained through the MD simulations can provide theoretical support for the applications and simulations of solid-liquid phase transition of sodium under relatively low-pressure conditions.

采用分子动力学（MD）方法和EAM/FS电位研究了压力（1 kPa ~ 500 MPa）对碱金属钠晶体非平衡熔融过程的影响。得到了宏观物理参数如势能、体积和热容（Cp）随压力的变化，并利用RDF和PTM方法分析了熔炼过程中原子团簇的演化。通过宏观物理参数分析，得到了不同压力下的非平衡熔化温度T m和熔化时间Δtm。压力对钠的熔化行为有显著的影响，特别是在压力低于150mpa时。T′m随压力的增大而增大，在1 kPa ~ 500 MPa压力范围内，T′m变化范围为423 ~ 464 K，与实验数据一致。随着压力的增加，Δtm先减小后增大，在90 MPa时熔化时间最短为7.6 ps。RDF分析和PTM分析都能很好地描述钠熔融的相变过程，也表明T′m随压力的增加而增大。PTM分析方法可以有效地研究不同钠原子团簇（BCC、HCP、FCC和其他团簇）在钠熔化过程中的转变。研究发现，随着温度的升高，一些BCC团簇直接转变为Other团簇，而另一些则先转变为中间FCC和HCP团簇，然后再转变为Other团簇。采用PTM分析方法测定钠的T′m范围为425 K ~ 467 K，与Cp分析结果一致。在钠晶体熔化过程中，宏观物理参数的变化与原子团簇的演化有很好的对应关系。这两种变化都能揭示钠的熔融过程。通过MD模拟得到的与钠熔融有关的热力学参数可以为相对低压条件下钠的固液相变的应用和模拟提供理论支持。

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引用次数: 0

Hydrate equilibrium conditions of a synthetic natural gas in the presence of methanol: Experimental study and thermodynamic modeling 甲醇存在下合成天然气水合物平衡条件：实验研究和热力学模型

IF 2.7 3区工程技术 Q3 CHEMISTRY, PHYSICAL

Fluid Phase Equilibria

Pub Date : 2025-09-24 DOI: 10.1016/j.fluid.2025.114595

Alireza Shariati , Ali Rasoolzadeh , Cor J. Peters

In this work, the hydrate equilibrium conditions of a synthetic natural gas (SNG) in the presence of pure water and three aqueous methanol solutions including 0.09570, 0.24805, and 0.50109 methanol mass fractions were measured in the pressure range of (5.06 to 12.56) MPa and temperature range of (256.74 to 291.41) K using the isochoric pressure-search method. Additionally, a modified van der Waals-Platteeuw (vdW-P) model was used to calculate the hydrate equilibrium conditions of the SNG hydrate. The UNIQUAC and Flory-Huggins (FH) activity coefficient models were applied to compute the water activity in the presence of methanol and the Peng-Robinson equation of state (PR EoS) was used for the vapor phase. It was determined that (vdW-P + PR + UNIQUAC) and (vdW-P + PR + FH) resulted in the average absolute deviations of 0.41 K and 0.25 K, respectively.

在压力（5.06 ~ 12.56）MPa、温度（256.74 ~ 291.41）K范围内，采用等时压力搜索法测定了合成天然气（SNG）在纯水、甲醇质量分数（0.09570、0.24805、0.50109）三种甲醇水溶液存在下的水合物平衡条件。此外，采用改进的van der Waals-Platteeuw （vdW-P）模型计算了天然气水合物的水合物平衡条件。采用UNIQUAC和Flory-Huggins （FH）活度系数模型计算甲醇存在时的水活度，采用Peng-Robinson状态方程（PR EoS）计算气相。结果表明，（vdW-P + PR + UNIQUAC）和（vdW-P + PR + FH）的平均绝对偏差分别为0.41 K和0.25 K。

引用次数: 0