Artigos de revistas: "Thermodynamic modelling using COSMO-RS"

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Roy, Sandra, Mounir Jaidann, Sophie Ringuette, Louis-Simon Lussier e Hakima Abou-Rachid. "Predictions of thermodynamic properties of energetic materials using COSMO-RS". Procedia Computer Science 1, n.º 1 (maio de 2010): 1203–11. http://dx.doi.org/10.1016/j.procs.2010.04.134.

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Kahlen, Jens, Kai Masuch e Kai Leonhard. "Modelling cellulose solubilities in ionic liquids using COSMO-RS". Green Chemistry 12, n.º 12 (2010): 2172. http://dx.doi.org/10.1039/c0gc00200c.

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Mechergui, Amal, Alsu I. Akhmetshina, Olga V. Kazarina, Maria E. Atlaskina, Anton N. Petukhov e Ilya V. Vorotyntsev. "Acidic Gases Solubility in Bis(2-Ethylhexyl) Sulfosuccinate Based Ionic Liquids Using the Predictive Thermodynamic Model". Membranes 10, n.º 12 (16 de dezembro de 2020): 429. http://dx.doi.org/10.3390/membranes10120429.

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To properly design ionic liquids (ILs) adopted for gases separation uses, a knowledge of ILs thermodynamic properties as well their solubilities with the gases is essential. In the present article, solubilities of CO2 and H2S in bis(2-Ethylhexyl)sulfosuccinate based ILs were predicted using the conductor like screening model for real solvents COSMO-RS. According to COSMO-RS calculations, the influence of the cation change was extensively analyzed. The obtained data are used for the prediction of adequate solvent candidates. Moreover, to understand the intrinsic behavior of gases solubility the free volume of the chosen ILs and their molecular interactions with respectively CO2 and H2S were computed. The results suggest that hydrogen bonding interactions in ILs and between ILs and the gases have a pivotal influence on the solubility.

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Dong, Shilong, Xiaoyan Sun, Lili Wang, Yanjing Li, Wenying Zhao, Li Xia e Shuguang Xiang. "Prediction, Application, and Mechanism Exploration of Liquid–Liquid Equilibrium Data in the Extraction of Aromatics Using Sulfolane". Processes 11, n.º 4 (16 de abril de 2023): 1228. http://dx.doi.org/10.3390/pr11041228.

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Liquid–liquid equilibrium (LLE) data are critical for the design and optimization of processes for extracting aromatics. Partial LLE data for the non-aromatic–aromatic–sulfolane ternary system were acquired at 313.15 K and 101.3 kPa. The LLE data for the extraction of aromatics using sulfolane were predicted using the COSMO-RS model. Correspondingly, the predicted and experimental data were analyzed using the root mean square deviation (RMSD), distribution coefficient (D), and separation factor (S). The COSMO-RS model could better predict the LLE data for the extraction of aromatics by sulfolane. The results of quantum chemical calculation show that hydrogen bonds and van der Waals interactions between sulfolane–benzene and sulfolane–toluene were responsible for the strong selectivity of sulfolane for benzene and toluene over alkanes. The LLE data predicted by the COSMO-RS method using the UNIQUAC thermodynamic model were subjected to correlation analysis. The calculated RMSD values were all less than 0.0180, and the relative deviation (δ) between the simulated value of the main process index for the extraction column and the actual data was less than 2.5%, indicating that the obtained binary interaction parameters can be reliably used in designing and optimizing the extraction of aromatics using sulfolane.

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Hyttinen, Noora, Reyhaneh Heshmatnezhad, Jonas Elm, Theo Kurtén e Nønne L. Prisle. "Technical note: Estimating aqueous solubilities and activity coefficients of mono- and α,ω-dicarboxylic acids using COSMOtherm". Atmospheric Chemistry and Physics 20, n.º 21 (9 de novembro de 2020): 13131–43. http://dx.doi.org/10.5194/acp-20-13131-2020.

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Abstract. We have used the COSMOtherm program to estimate activity coefficients and solubilities of mono- and α,ω-dicarboxylic acids and water in binary acid–water systems. The deviation from ideality was found to be larger in the systems containing larger acids than in the systems containing smaller acids. COnductor-like Screening MOdel for Real Solvents (COSMO-RS) underestimates experimental monocarboxylic acid activity coefficients by less than a factor of 2, but experimental water activity coefficients are underestimated more especially at high acid mole fractions. We found a better agreement between COSMOtherm-estimated and experimental activity coefficients of monocarboxylic acids when the water clustering with a carboxylic acid and itself was taken into account using the dimerization, aggregation, and reaction extension (COSMO-RS-DARE) of COSMOtherm. COSMO-RS-DARE is not fully predictive, but fit parameters found here for water–water and acid–water clustering interactions can be used to estimate thermodynamic properties of monocarboxylic acids in other aqueous solvents, such as salt solutions. For the dicarboxylic acids, COSMO-RS is sufficient for predicting aqueous solubility and activity coefficients, and no fitting to experimental values is needed. This is highly beneficial for applications to atmospheric systems, as these data are typically not available for a wide range of mixing states realized in the atmosphere, due to a lack of either feasibility of the experiments or sample availability. Based on effective equilibrium constants of different clustering reactions in the binary solutions, acid dimer formation is more dominant in systems containing larger dicarboxylic acids (C5–C8), while for monocarboxylic acids (C1–C6) and smaller dicarboxylic acids (C2–C4), hydrate formation is more favorable, especially in dilute solutions.

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Pilli, Santhi Raju, Tamal Banerjee e Kaustubha Mohanty. "Ionic Liquids as Green Solvents for the Extraction of Endosulfan from Aqueous Solution: A Quantum Chemical Approach". Chemical Product and Process Modeling 8, n.º 1 (8 de junho de 2013): 1–14. http://dx.doi.org/10.1515/cppm-2013-0001.

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Abstract This work presents a judicious screening of 986 possible ionic liquid (IL) combinations for the removal of Endosulfan using COSMO-RS (Conductor-like Screening Model for Real Solvents) model. Initially, benchmarking studies have been carried out for α-Endosulfan, β-Endosulfan, Endosulfan sulfate, Endosulfan-alcohol, Endosulfan lactone, and Endosulfan ether by comparing COSMO-RS experimental and predicted octanol–water partition coefficients. Thereafter, COSMO-RS selectivity predictions were done on 986 ionic liquid combinations at infinite dilution. The order of selectivity for the five cation groups were found to be as follows: [TBP] > [TIBMP] > [TBMP] > [C2DMIM] > [BEPYR] > [DPPYR] > [C4DMIM] > [C8MPY] > [BTNH] > [BETNH]. Highest selectivity was obtained for phosphonium based IL namely: [TBP][TOS] (212.5). Anions such as [C8H17SO4], [Br], [Sal], [TOS], [MDEGSO4], and [DEC] contributed high selectivities because of the absence of sterical shielding effect around their charge centers. Further capacity and the performance index (PI) values were calculated and predicted along with selectivity. The increasing order of performance index values were found to follow: [TBP][Sal] (1.71+E5) > [DPPYR][Br] (1.07+E6) > [C2DMIM] (1.01+E6) > [C8MPY][Cl] (1.6+E5) > [BETNH][DEC] (1.2+E5).

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Kurnia, Kiki Adi, Choo Jia How, Pranesh Matheswaran, Mohd Hilmi Noh e M. Amin Alamsjah. "Insight into the molecular mechanism that controls the solubility of CH4 in ionic liquids". New Journal of Chemistry 44, n.º 2 (2020): 354–60. http://dx.doi.org/10.1039/c9nj04973h.

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The electrostatic – misfit energy arise from repulsive interaction of CH₄ plays a dominant role in determining its solubility in ILs. Modelling using COSMO-RS shows that IL size and van der Walls forces only have marginal influences on CH₄ solubility.

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Qin, Yanmin, Xiaopeng Chen, Linlin Wang, Xiaojie Wei, Weijian Nong, Xuejuan Wei e Jiezhen Liang. "Experimental Determination and Computational Prediction of Dehydroabietic Acid Solubility in (−)-α-Pinene + (−)-β-Caryophyllene + P-Cymene System". Molecules 27, n.º 4 (11 de fevereiro de 2022): 1220. http://dx.doi.org/10.3390/molecules27041220.

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The solubility of dehydroabietic acid in (−)-α-pinene, p-cymene, (−)-β-caryophyllene, (−)-α-pinene + p-cymene, (−)-β-caryophyllene + p-cymene and (−)-α-pinene + (−)-β-caryophyllene were determined using the laser monitoring method at atmospheric pressure. The solubility of dehydroabietic acid was positively correlated with temperature from 295.15 to 339.46 K. (−)-α-pinene, p-cymene, and (−)-β-caryophyllene were found to be suitable for the solubilization of dehydroabietic acid. In addition, the non-random two liquid (NRTL), universal quasi-chemical (UNIQUAC), modified Apelblat, modified Wilson, modified Wilson–van’t Hoff, and λh models were applied to correlate the determined solubility data. The modified Apelblat model gave the minor deviation for dehydroabietic acid in monosolvents, while the λh equation showed the best result in the binary solvents. A comparative analysis of compatibility between solutes and solvents was carried out using Hansen solubility parameters. The thermodynamic functions of ΔsolH0, ΔsolS0, ΔsolG0 were calculated according to the van’t Hoff equation, indicating that the dissolution was an entropy-driven heat absorption process. The Conductor-like Screening Model for Real Solvents (COSMO-RS) combined with an experimental value was applied to predict the reasonable solubility data of dehydroabietic acid in the selected solvents systems. The interaction energy of the dehydroabietic acid with the solvent was analyzed by COSMO-RS.

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Bezold, Franziska, Maria E. Weinberger e Mirjana Minceva. "Assessing solute partitioning in deep eutectic solvent-based biphasic systems using the predictive thermodynamic model COSMO-RS". Fluid Phase Equilibria 437 (abril de 2017): 23–33. http://dx.doi.org/10.1016/j.fluid.2017.01.001.

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Jeliński, Tomasz, e Piotr Cysewski. "Quantification of Caffeine Interactions in Choline Chloride Natural Deep Eutectic Solvents: Solubility Measurements and COSMO-RS-DARE Interpretation". International Journal of Molecular Sciences 23, n.º 14 (15 de julho de 2022): 7832. http://dx.doi.org/10.3390/ijms23147832.

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Solubility of active pharmaceutical ingredients is an important aspect of drug processing and formulation. Although caffeine was a subject of many studies aiming to quantify saturated solutions, many applied solvents suffer from not being environmentally friendly. This work fills this gap by presenting the results of solubility measurements in choline chloride natural deep eutectic solvents, ccNADES, comprising one of seven of the following polyalcohols: glycerol, sorbitol, xylitol, glucose, sucrose, maltose and fructose. The ratio of ccNADES components was optimized for maximizing caffeine solubility at room temperature. Additionally, temperature dependent solubility was measured for the first four systems exhibiting the highest solubility potential, both in their neat forms and in mixtures with water. Results were used for intermolecular interactions assessments using the COSMO-RS-DARE approach, which led to a perfect match between experimental and computed solubility values. An important methodological discussion was provided for an appropriate definition of the systems. Surprising linear trends were observed between the values of fitting parameters and water-ccNADES composition. In addition, comments on selection of the values of the fusion thermodynamic parameters were provided, which led to the conclusion that COSMO-RS-DARE solubility computations can effectively compensate for the inaccuracies of these important physicochemical properties.

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Abdallah, Maha M., Simon Müller, Andrés González de Castilla, Pavel Gurikov, Ana A. Matias, Maria do Rosário Bronze e Naiara Fernández. "Physicochemical Characterization and Simulation of the Solid–Liquid Equilibrium Phase Diagram of Terpene-Based Eutectic Solvent Systems". Molecules 26, n.º 6 (23 de março de 2021): 1801. http://dx.doi.org/10.3390/molecules26061801.

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The characterization of terpene-based eutectic solvent systems is performed to describe their solid–liquid phase transitions. Physical properties are measured experimentally and compared to computed correlations for deep eutectic solvents (DES) and the percentage relative error er for the density, surface tension, and refractive index is obtained. The thermodynamic parameters, including the degradation, glass transition and crystallization temperatures, are measured using DSC and TGA. Based on these data, the solid–liquid equilibrium phase diagrams are calculated for the ideal case and predictions are made using the semi-predictive UNIFAC and the predictive COSMO RS models, the latter with two different parametrization levels. For each system, the ideal, experimental, and predicted eutectic points are obtained. The deviation from ideality is observed experimentally and using the thermodynamic models for Thymol:Borneol and Thymol:Camphor. In contrast, a negative deviation is observed only experimentally for Menthol:Borneol and Menthol:Camphor. Moreover, the chemical interactions are analyzed using FTIR and 1H-NMR to study the intermolecular hydrogen bonding in the systems.

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Cysewski, Piotr, Maciej Przybyłek e Tomasz Jeliński. "Intermolecular Interactions as a Measure of Dapsone Solubility in Neat Solvents and Binary Solvent Mixtures". Materials 16, n.º 18 (21 de setembro de 2023): 6336. http://dx.doi.org/10.3390/ma16186336.

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Dapsone is an effective antibacterial drug used to treat a variety of conditions. However, the aqueous solubility of this drug is limited, as is its permeability. This study expands the available solubility data pool for dapsone by measuring its solubility in several pure organic solvents: N-methyl-2-pyrrolidone (CAS: 872-50-4), dimethyl sulfoxide (CAS: 67-68-5), 4-formylmorpholine (CAS: 4394-85-8), tetraethylene pentamine (CAS: 112-57-2), and diethylene glycol bis(3-aminopropyl) ether (CAS: 4246-51-9). Furthermore, the study proposes the use of intermolecular interactions as molecular descriptors to predict the solubility of dapsone in neat solvents and binary mixtures using machine learning models. An ensemble of regressors was used, including support vector machines, random forests, gradient boosting, and neural networks. Affinities of dapsone to solvent molecules were calculated using COSMO-RS and used as input for model training. Due to the polymorphic nature of dapsone, fusion data are not available, which prohibits the direct use of COSMO-RS for solubility calculations. Therefore, a consonance solvent approach was tested, which allows an indirect estimation of the fusion properties. Unfortunately, the resulting accuracy is unsatisfactory. In contrast, the developed regressors showed high predictive potential. This work documents that intermolecular interactions characterized by solute–solvent contacts can be considered valuable molecular descriptors for solubility modeling and that the wealth of encoded information is sufficient for solubility predictions for new systems, including those for which experimental measurements of thermodynamic properties are unavailable.

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Królikowska, Marta, Michał Skonieczny, Kamil Paduszyński e Maciej Zawadzki. "Vapor Pressure and Physicochemical Properties of {LiBr + IL-Based Additive + Water} Mixtures: Experimental Data and COSMO-RS Predictions". Journal of Solution Chemistry 50, n.º 4 (abril de 2021): 473–502. http://dx.doi.org/10.1007/s10953-021-01071-w.

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AbstractIn recent years, many compounds have been proposed as additives to conventional working fluids to improve the performance of the absorption refrigeration system. The main aim of this research is to show the influence of ionic liquid based additives on thermodynamic and physicochemical properties of {LiBr + water} solutions. The following additives: 3-(1-methyl-morpholinium)propane-1-sulfonate, N,N-di(2-hydroxyethyl)-N,N-dimethylammonium bromide, and N,N,N-tri(2-hydroxy-ethyl)-N-methylammonium bromide have been added to aqueous lithium bromide solutions (IL to LiBr mass fraction, w2 = 0.3). The physicochemical and thermodynamic properties of {LiBr (1) + additive (2) + water (3)} and {LiBr + water} systems including (vapor + liquid) phase equilibria (VLE), density (ρ) and dynamic viscosity (η) were determined over wide temperature and composition ranges. The conductor-like screening model for real solvents (COSMO-RS) was used for the VLE data prediction. For the density and dynamic viscosity correlations, empirical equations were applied. A comparison of experimental data for {LiBr + additive + water} with those for {LiBr + water} systems shows the influence of using the additives proposed in this work. The data presented are complementary to the current state of knowledge in this area and provide directions for future research.

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Ferro, Víctor R., Sonia Merino, Rafael Lopez e José L. Valverde. "An Insight into the Molecular Electronic Structure of Graphene Oxides and Their Interactions with Molecules of Different Polarities Using Quantum Chemical and COSMO-RS Calculations". Molecules 29, n.º 16 (13 de agosto de 2024): 3839. http://dx.doi.org/10.3390/molecules29163839.

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A systematic theoretical study on the molecular electronic structure of graphene and its oxides, including their interactions with molecular species of different polarity, was carried out. The influence of the O/C atomic ratio in the graphene oxides was also evaluated. Quantum chemical and COSMO-based statistical-thermodynamic calculations were performed. Geometry optimizations demonstrated that graphene sheets are structurally distorted by oxygen substitution, although they show high resistance to deformation. Furthermore, under axial O-C bonding, proton-donor and proton-acceptor centers are created on the graphene oxide surface, which could acquire an amphoteric character. In low-oxidized graphene oxides, H-bonding centers coexist with neutral highly polarizable π electron clouds. Deep graphene oxidation is also related to the formation of a quasi-two-dimensional H-bond network. These two phenomena are responsible for the exceptional adsorption and catalytic properties and the potential proton conductivity of graphene oxides. The current calculations demonstrated that the interactions of polar molecular species with deep-oxidized graphene derivatives are thermodynamically favorable, but not with low-oxidized ones. The capacity of the quantum chemical and COSMO-RS calculations to model all these issues opens the possibility of selecting or designing graphene-based materials with optimized properties for specific applications. Also, they are valuable in selecting/designing solvents with good exfoliant properties with respect to certain graphene derivatives.

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Putra, Venansius G. P., Weni Chaniago, Nuzulia Izmi, Selma Mutiarahma, Kiki Adi Kurnia, Miguel Palma e Widiastuti Setyaningsih. "Assessment of Solvent Extraction using Sonication to Recover Tryptophan from Kappaphycus alvarezii (Doty) Doty ex Silva: Experimental and Modelling". Trends in Sciences 21 (24 de julho de 2024): Manuscript. http://dx.doi.org/10.48048/tis.2024.8197.

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The application of Kappaphycus alvarezii in the food system has attracted researchers due to its bioactive compounds, including tryptophan. The present study was conducted to extract tryptophan from K. alvarezii with the aid of sonication. A reduced multilevel factorial design was conducted to evaluate the effect of solvent, ultrasound power, duty-pulse cycle, time and temperature on the recovery of tryptophan. Analysis of variance suggested that the type of solvent and combination setting of power and duty-pulse cycle significantly influenced the extraction (p < 0.05). In contrast, extraction time and temperature did not alter the extraction (p > 0.05). The optimum was using ethanol, ultrasound power 80 %, pulse duty-cycle 0.8 s–1, extraction time 10 min, and temperature 25 °C and tryptophan concentration was 56.41 ± 2.42 mg L–1. Subsequently, a COnducto-like Screening MOdel for Real Solvent (COSMO-RS) was performed to clarify the impact of solvent affinity and polarity on the tryptophan extraction from K. alvarezii.

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Hazim Chan, Nurshakirin, Hanee Farzana Hizaddin, Ramalingam Anantharaj e Tamal Banerjee. "Ethylsulphate-Based Ionic Liquids in the Liquid–Liquid Extraction of Pyrrole and Pyridine from Isododecane at 298.15 K". Chemical Product and Process Modeling 10, n.º 3 (1 de setembro de 2015): 161–71. http://dx.doi.org/10.1515/cppm-2014-0027.

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Abstract Ternary liquid-liquid equilibria for four systems containing ionic liquids {1-ethyl-3-methylimidazolium ethylsulphate ([EMIM][EtSO4]) and 1-ethyl-3-methylpyridinium ethylsulphate ([EMPY][EtSO4])}(1)+pyrrole/pyridine(2)+isododecane (3) have been determined at 298.15 K. The solute distribution coefficient and selectivity were calculated from experimental LLE data. All systems showed high distribution coefficient and selectivity values at the entire range of pyrrole or pyridine in feed. The consistency of experimental data was ascertained by applying the Othmer-Tobias and hand equations. Furthermore, the experimental LLE data have been compared and correlated using COSMO-RS, NRTL and UNIQUAC models. The influence of aromatic structure without inside ring of cation has a significant role on denitrification process at 298.15 K.

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Słupek, Edyta, Patrycja Makoś e Jacek Gębicki. "Theoretical and Economic Evaluation of Low-Cost Deep Eutectic Solvents for Effective Biogas Upgrading to Bio-Methane". Energies 13, n.º 13 (1 de julho de 2020): 3379. http://dx.doi.org/10.3390/en13133379.

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This paper presents the theoretical screening of 23 low-cost deep eutectic solvents (DESs) as absorbents for effective removal of the main impurities from biogas streams using a conductor-like screening model for real solvents (COSMO-RS). Based on thermodynamic parameters, i.e., the activity coefficient, excess enthalpy, and Henry’s constant, two DESs composed of choline chloride: urea in a 1:2 molar ratio (ChCl:U 1:2), and choline chloride: oxalic acid in a 1:2 molar ratio (ChCl:OA 1:2) were selected as the most effective absorbents. The σ-profile and σ-potential were used in order to explain the mechanism of the absorptive removal of CO2, H2S, and siloxanes from a biogas stream. In addition, an economic analysis was prepared to demonstrate the competitiveness of new DESs in the sorbents market. The unit cost of 1 m3 of pure bio-methane was estimated to be in the range of 0.35–0.37 EUR, which is comparable to currently used technologies.

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Walker, Pierre J., Tianpu Zhao, Andrew J. Haslam e George Jackson. "Ab initio development of generalized Lennard-Jones (Mie) force fields for predictions of thermodynamic properties in advanced molecular-based SAFT equations of state". Journal of Chemical Physics 156, n.º 15 (21 de abril de 2022): 154106. http://dx.doi.org/10.1063/5.0087125.

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A methodology for obtaining molecular parameters of a modified statistical associating fluid theory for variable-range interactions of Mie form (SAFT-VR Mie) equation of state (EoS) from ab initio calculations is proposed for non-associative species that can be modeled as single spherical segments. The methodology provides a strategy to map interatomic or intermolecular potentials obtained from ab initio quantum-chemistry calculations to the corresponding Mie potentials that can be used within the SAFT-VR Mie EoS. The inclusion of corrections for quantum and many-body effects allows for an excellent, fully predictive description of the vapor–liquid envelope and other bulk thermodynamic properties of noble gases; this description is of similar or superior quality to that obtained using SAFT-VR Mie with parameters regressed in the traditional way using experimental thermodynamic-property data. The methodology is extended to an anisotropic species, methane, where similar levels of accuracy are obtained. The efficacy of using less-accurate quantum-chemistry methods in this methodology is explored, showing that these methods do not provide satisfactory results, although we note that the description is nevertheless substantially better than those obtained using the conductor-like screening model for describing real solvents (COSMO-RS), the only other fully predictive ab initio method currently available. Overall, the reliance on thermophysical data is completely dispensed with, providing the first extensible, wholly predictive SAFT-type EoSs.

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Lazović, Mila, Ilija Cvijetić, Milica Jankov, Dušanka Milojković-Opsenica, Jelena Trifković e Petar Ristivojević. "Efficiency of Natural Deep Eutectic Solvents to Extract Phenolic Compounds from Agrimonia eupatoria: Experimental Study and In Silico Modelling". Plants 11, n.º 18 (8 de setembro de 2022): 2346. http://dx.doi.org/10.3390/plants11182346.

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To replace common organic solvents that present inherent toxicity and have high volatility and to improve the extraction efficiency, a range of natural deep eutectic solvents (NADESs) were evaluated for the extraction of phenolic compounds from Agrimonia eupatoria. Screening of NADES efficiency was carried out based on the total phenolic and flavonoid content and radical-scavenging activity, determined by spectrophotometry, as well as phenolic compounds quantified, obtained using ultra-high-performance liquid chromatography with a diode array detector and a triple-quadrupole mass spectrometer. Increased extraction efficiency when compared with organic solvent was achieved using NADES mixtures choline chloride (ChCl):urea 1:2 and choline chloride:glycerol 1:1. Flavonol glycosides were the most abundant compounds in all extracts. The COSMO-RS model provided insights into the most important intermolecular interactions that drive the extraction process. Moreover, it could explain the extraction efficiency of flavonol glycosides using ChCl:glycerol NADES. The current article offers experimental evidence and mechanistic insights for the selection of optimal NADES to extract bioactive components from Agrimonia eupatoria.

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Alluri, Venkata Sai Priyatham Varma, William (Hoang Chi Hieu) Nguyen e Amr Henni. "Determination of the Dissociation Constants (pKa) of Eight Amines of Importance in Carbon Capture: Computational Chemistry Calculations, and Artificial Neural Network Models". Liquids 3, n.º 2 (20 de maio de 2023): 214–45. http://dx.doi.org/10.3390/liquids3020016.

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This work focuses on determining the dissociation constants (pKa) of eight amines, namely, 3-(Diethylamino) propylamine, 1,3-Diaminopentane, 3-Butoxypropylamine, 2-(Methylamino) ethanol, Bis(2-methoxyethyl) amine, α-Methylbenzylamine, 2-Aminoheptane, and 3-Amino-1-phenylbutane, within temperatures ranging from 293.15 K to 323.15 K. The thermodynamic properties of the protonated reactions were regressed from the pKa work. In addition, the protonated order of both 3-(Diethylamino) propylamine and 1,3-Diaminopentane were determined using computational chemistry methods owing to their unsymmetrical structures. In addition to the experimental methods, the dissociation constants at the standard temperature (298.15 K) were also estimated using group functional models (paper–pencil) and computational methods. The computational methods include COSMO-RS and computational chemistry calculations. An artificial neural network (ANN) method was employed to model the data by collecting and combining the experimental properties to estimate the missing pKa values. Although the ANN models can provide acceptable results, they depend on the availability of the data. Instead of using the experimental properties, they were generated using software such as Aspen Plus or CosmothermX. The simulated ANN model can also provide very good fits to the experimental constant values.

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Ortega, Juan, Elena Marrero e José Palomar. "Description of Thermodynamic Behavior of the Systems Formed by Alkyl Ethanoates with 1-Chloroalkanes Using the COSMO-RS Methodology Contributing with New Experimental Information". Industrial & Engineering Chemistry Research 47, n.º 9 (maio de 2008): 3253–64. http://dx.doi.org/10.1021/ie071467m.

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Elboughdiri, Noureddine, Hana Ferkous, Karima Rouibah, Abir Boublia, Amel Delimi, Krishna Kumar Yadav, Alessandro Erto et al. "Comprehensive Investigation of Cu2+ Adsorption from Wastewater Using Olive-Waste-Derived Adsorbents: Experimental and Molecular Insights". International Journal of Molecular Sciences 25, n.º 2 (14 de janeiro de 2024): 1028. http://dx.doi.org/10.3390/ijms25021028.

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This study investigates the efficacy of adsorbents from locally sourced olive waste—encompassing olive skins, leaves, and pits, recovered from the initial centrifugation of olives (OWP)—and a composite with sodium alginate (OWPSA) for the removal of Cu2+ ions from synthetic wastewater. Experimental analyses conducted at room temperature, with an initial Cu2+ concentration of 50 mg/L and a solid/liquid ratio of 1 g/L, showed that the removal efficiencies were approximately 79.54% and 94.54% for OWP and OWPSA, respectively, highlighting the positive impact of alginate on adsorption capacity. Utilizing statistical physics isotherm models, particularly the single-layer model coupled to real gas (SLMRG), allowed us to robustly fit the experimental data, providing insights into the adsorption mechanisms. Thermodynamic parameters affirmed the spontaneity and endothermic nature of the processes. Adsorption kinetics were interpreted effectively using the pseudo-second-order (PSO) model. Molecular modeling investigations, including the conductor-like screening model for real solvents (COSMO-RS), density functional theory (DFT), and atom-in-molecule (AIM) analysis, unveiled intricate molecular interactions among the adsorbent components—cellulose, hemicellulose, lignin, and alginate—and the pollutant Cu2+, confirming their physically interactive nature. These findings emphasize the synergistic application of experimental and theoretical approaches, providing a comprehensive understanding of copper adsorption dynamics at the molecular level. This methodology holds promise for unraveling intricate processes across various adsorbent materials in wastewater treatment applications.

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Cysewski, Piotr, Tomasz Jeliński e Maciej Przybyłek. "Intermolecular Interactions of Edaravone in Aqueous Solutions of Ethaline and Glyceline Inferred from Experiments and Quantum Chemistry Computations". Molecules 28, n.º 2 (7 de janeiro de 2023): 629. http://dx.doi.org/10.3390/molecules28020629.

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Edaravone, acting as a cerebral protective agent, is administered to treat acute brain infarction. Its poor solubility is addressed here by means of optimizing the composition of the aqueous choline chloride (ChCl)-based eutectic solvents prepared with ethylene glycol (EG) or glycerol (GL) in the three different designed solvents compositions. The slurry method was used for spectroscopic solubility determination in temperatures between 298.15 K and 313.15 K. Measurements confirmed that ethaline (ETA = ChCl:EG = 1:2) and glyceline (GLE = ChCl:GL = 1:2) are very effective solvents for edaravone. The solubility at 298.15 K in the optimal compositions was found to be equal xE = 0.158 (cE = 302.96 mg/mL) and xE = 0.105 (cE = 191.06 mg/mL) for glyceline and ethaline, respectively. In addition, it was documented that wetting of neat eutectic mixtures increases edaravone solubility which is a fortunate circumstance not only from the perspective of a solubility advantage but also addresses high hygroscopicity of eutectic mixtures. The aqueous mixture with 0.6 mole fraction of the optimal composition yielded solubility values at 298.15 K equal to xE = 0.193 (cE = 459.69 mg/mL) and xE = 0.145 (cE = 344.22 mg/mL) for glyceline and ethaline, respectively. Since GLE is a pharmaceutically acceptable solvent, it is possible to consider this as a potential new liquid form of this drug with a tunable dosage. In fact, the recommended amount of edaravone administered to patients can be easily achieved using the studied systems. The observed high solubility is interpreted in terms of intermolecular interactions computed using the Conductor-like Screening Model for Real Solvents (COSMO-RS) approach and corrected for accounting of electron correlation, zero-point vibrational energy and basis set superposition errors. Extensive conformational search allowed for identifying the most probable contacts, the thermodynamic and geometric features of which were collected and discussed. It was documented that edaravone can form stable dimers stabilized via stacking interactions between five-membered heterocyclic rings. In addition, edaravone can act as a hydrogen bond acceptor with all components of the studied systems with the highest affinities to ion pairs of ETA and GLE. Finally, the linear regression model was formulated, which can accurately estimate edaravone solubility utilizing molecular descriptors obtained from COSMO-RS computations. This enables the screening of new eutectic solvents for finding greener replacers of designed solvents. The theoretical analysis of tautomeric equilibria confirmed that keto-isomer edaravone is predominant in the bulk liquid phase of all considered deep eutectic solvents (DES).

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Rouibah, Karima, Hana Ferkous, Meniai Abdessalam-Hassan, Bencheikh Lehocine Mossab, Abir Boublia, Christel Pierlot, Amdjed Abdennouri et al. "Exploring the Efficiency of Algerian Kaolinite Clay in the Adsorption of Cr(III) from Aqueous Solutions: Experimental and Computational Insights". Molecules 29, n.º 9 (4 de maio de 2024): 2135. http://dx.doi.org/10.3390/molecules29092135.

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The current study comprehensively investigates the adsorption behavior of chromium (Cr(III)) in wastewater using Algerian kaolinite clay. The structural and textural properties of the kaolinite clay are extensively characterized through a range of analytical methods, including XRD, FTIR, SEM-EDS, XPS, laser granulometry, N2 adsorption isotherm, and TGA–DTA. The point of zero charge and zeta potential are also assessed. Chromium adsorption reached equilibrium within five minutes, achieving a maximum removal rate of 99% at pH 5. Adsorption equilibrium is modeled using the Langmuir, Freundlich, Temkin, Elovich, and Dubinin–Radushkevitch equations, with the Langmuir isotherm accurately describing the adsorption process and yielding a maximum adsorption capacity of 8.422 mg/g for Cr(III). Thermodynamic parameters suggest the spontaneous and endothermic nature of Cr(III) sorption, with an activation energy of 26.665 kJ/mol, indicating the importance of diffusion in the sorption process. Furthermore, advanced DFT computations, including COSMO-RS, molecular orbitals, IGM, RDG, and QTAIM analyses, are conducted to elucidate the nature of adsorption, revealing strong binding interactions between Cr(III) ions and the kaolinite surface. The integration of theoretical and experimental data not only enhances the understanding of Cr(III) removal using kaolinite but also demonstrates the effectiveness of this clay adsorbent for wastewater treatment. Furthermore, this study highlights the synergistic application of empirical research and computational modeling in elucidating complex adsorption processes.

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Kato, Ryo, e Jürgen Gmehling. "Systems with ionic liquids: Measurement of VLE and γ∞ data and prediction of their thermodynamic behavior using original UNIFAC, mod. UNIFAC(Do) and COSMO-RS(Ol)". Journal of Chemical Thermodynamics 37, n.º 6 (junho de 2005): 603–19. http://dx.doi.org/10.1016/j.jct.2005.04.010.

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Qin, Hao, Zihao Wang, Zhen Song, Xiang Zhang e Teng Zhou. "High-Throughput Computational Screening of Ionic Liquids for Butadiene and Butene Separation". Processes 10, n.º 1 (15 de janeiro de 2022): 165. http://dx.doi.org/10.3390/pr10010165.

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The separation of 1,3-butadiene (1,3-C4H6) and 1-butene (n-C4H8) is quite challenging due to their close boiling points and similar molecular structures. Extractive distillation (ED) is widely regarded as a promising approach for such a separation task. For ED processes, the selection of suitable entrainer is of central importance. Traditional ED processes using organic solvents suffer from high energy consumption. To tackle this issue, the utilization of ionic liquids (ILs) can serve as a potential alternative. In this work, a high-throughput computational screening of ILs is performed to find proper entrainers, where 36,260 IL candidates comprising of 370 cations and 98 anions are involved. COSMO-RS is employed to calculate the infinite dilution extractive capacity and selectivity of the 36,260 ILs. In doing so, the ILs that satisfy the prespecified thermodynamic criteria and physical property constraints are identified. After the screening, the resulting IL candidates are sent for rigorous process simulation and design. 1,2,3,4,5-pentamethylimidazolium methylcarbonate is found to be the optimal IL solvent. Compared with the benchmark ED process where the organic solvent N-methyl-2-pyrrolidone is adopted, the energy consumption is reduced by 26%. As a result, this work offers a new IL-based ED process for efficient 1,3-C4H6 production.

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Fernández, Luis, Juan Ortega, José Palomar, Francisco Toledo e Elena Marrero. "Description of the Behavior of Dichloroalkanes-Containing Solutions with Three [bXmpy][BF4] Isomers, Using the Experimental Information of Thermodynamic Properties, 1H NMR Spectral and the COSMO-RS-Methodology". Journal of Physical Chemistry B 119, n.º 8 (17 de fevereiro de 2015): 3527–34. http://dx.doi.org/10.1021/jp510884t.

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Tonelli, M., I. Wainer e E. Curchitser. "A modelling study of the hydrographic structure of the Ross Sea". Ocean Science Discussions 9, n.º 6 (6 de novembro de 2012): 3431–49. http://dx.doi.org/10.5194/osd-9-3431-2012.

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Abstract. Dense water formation around Antarctica is recognized as one of the most important processes to climate modulation, since that is where the linkage between the upper and lower limbs of Global Thermohaline Circulation takes place. Assessing whether these processes may be affected by rapid climate changes and all the related feedbacks may be crucial to fully understand the ocean heat transport and to provide future projections. Applying the Coordinated Ocean-Ice Reference (CORE) normal year forcing we have run a 100-yr simulation using Regional Ocean Model System (ROMS) with explicit sea-ice/ice-shelf thermodynamics. The normal year consists of single annual cycle of all the data that are representative of climatological conditions over decades and can be applied repeatedly for as many years of model integration as necessary. The experiment employed a circumpolar variable resolution (1/2° to 1/24°) grid reaching less than 5 km over the inner continental shelf. With Optimum Parameter Analysis (OMP) the main Ross Sea (RS) water masses are identified: Antarctic surface water (AASW), circumpolar deep water (CDW), shelf water (SW) and ice shelf water (ISW). Current configuration allows very realistic representation, where results compare extremely well to the observations.

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Navas, Ana, Juan Ortega, Tomás Martín e José Palomar. "Thermodynamic Analysis of Systems Formed by Alkyl Esters with α,ω-Alkyl Dibromides: New Experimental Information and the Use of a Dense Database to Describe Their Behavior Using the UNIFAC Group Contribution Method and the COSMO-RS Methodology". Industrial & Engineering Chemistry Research 49, n.º 24 (15 de dezembro de 2010): 12726–39. http://dx.doi.org/10.1021/ie101479v.

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Marrero, E., J. Ortega e J. Palomar. "Thermodynamic study of (alkyl esters+α,ω-alkyl dihalides) VII. and for 20 binary mixtures {xCu−1H2u−1CO2C3H7+(1−x)α,ω-ClCH2(CH2)v−2CH2Cl}, where u=1 to 4, α=1 and v=ω=2 to 6. An analysis of behavior using the COSMO-RS methodology". Journal of Chemical Thermodynamics 41, n.º 3 (março de 2009): 367–82. http://dx.doi.org/10.1016/j.jct.2008.10.007.

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Ramalingam, Anantharaj, e Tamal Banerjee. "Prediction and Validation of Carbon Dioxide Gas Solubility in Ionic Liquids at T=298K and Atmospheric Pressure using Quantum Chemical Approach". Chemical Product and Process Modeling 6, n.º 1 (7 de julho de 2011). http://dx.doi.org/10.2202/1934-2659.1576.

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Carbon dioxide (CO2) gas solubilities are predicted via quantum chemical calculations, which only requires molecular structure as initial information. The quantum chemical based Conductor like Screening Model for Real Solvents (COSMO-RS) has been adopted for this purpose. Predictions of gas solubility at temperatures ranging from (283.15 to 323.15 K) at 0.1 MPa were done for the IL:[EMIM][TFI]. The relative absolute deviation of around 30% shows that the quality of predictions is highly dependent on the infinite dilution activity coefficient of CO2 in [EMIM][TFI].Additionally thermodynamic parameters such as Gibb’s Energy of solvation, enthalpies and entropies have also been predicted and compared for the IL:[BMIM][BF4]. In addition, the carbon dioxide solubility in 16 ionic liquids comprising of imidazolium and pyridinium based cations was validated with reported values. The Root Mean Square Deviation (RMSD) obtained was: 3.09% [TFI], 6.5% [TFO] and 12% [PF6], respectively. Finally, the Henry’s constants of CO2 in 286 ionic liquids comprising of newer cations such as pyrrolidinium, piperidinium and morpholium were predicted at T=298.15 K. The saturated aromatic ring structure of pyrrolidinium, morpholinium and piperidinium based ionic liquids possessed low Henry’s constant values which indicates high solubility of CO2 in ionic liquids.

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Mgxadeni, Ncomeka, Bakusele Kabane, Indra Bahadur, Márcio L. L. Paredes, Rafael de P. Soares, Shailendra Kumar Singh, Faruq Mohammad e Ahmed Abdullah Soleiman. "Thermodynamic Properties, Activity Coefficients at Infinite Dilution and Cosmo‐SAC Modelling of Deep Eutectic Solvents at Different Temperatures". ChemistrySelect 8, n.º 30 (7 de agosto de 2023). http://dx.doi.org/10.1002/slct.202204192.

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AbstractA deep understanding of the solute‐ deep eutectic solvent (DESs) interactions is required for an appropriate selection of DESs as absorption media in the extraction of binary mixtures. As a result, these studies are done to evaluate the values of the activity coefficients at infinite dilution ( ), allowing us to define and understand the nature of these intermolecular interactions comprising DES mixtures with volatile organic solvents at different temperatures using gas liquid chromatography technique to determine the for 34 solutes in DESs [zinc chloride+acetic or phosphoric acid] prepared at 1 : 2 molar ratio for the temperature range (313.15–353.15) K. The thermal stability of the prepared DESs was determined by a thermogravimetric analyser. Excess thermodynamic parameters [partial molar excess enthalpies and Gibbs free energies ] were derived from the data. The selectivity and capacity values for the industrial separations were calculated and compared with the literature values of other DESs, ionic liquids, and sulfolane to assess the suitability of the investigated DESs for possible applications as extracting solvents. The selectivity and capacity values are high and therefore, [zinc chloride+acetic or phosphoric acid] can be used as a potential solvent to replace the currently used conventional solvents in the separation of the selected azeotropes. COSMO‐SAC predictions were qualitatively in very good agreement with the experimental data.

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Balchandani, Sweta, e Ramesh Singh. "Thermodynamic analysis using COSMO-RS studies of reversible ionic liquid 3-aminopropyl triethoxysilane blended with amine activators for CO2 absorption". Journal of Molecular Liquids, novembro de 2020, 114713. http://dx.doi.org/10.1016/j.molliq.2020.114713.

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Li, Youqi, Xiaopeng Chen, Linlin Wang, Xiaojie Wei, Minting Nong, Weijian Nong e Jiezhen Liang. "Measurement and Prediction of Isothermal Vapor–Liquid Equilibrium and Thermodynamic Properties of a Turpentine + Rosin System Using the COSMO-RS Model". ACS Omega, 4 de maio de 2022. http://dx.doi.org/10.1021/acsomega.1c05167.

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Arrad, Mouad, Kaj Thomsen, Simon Müller e Irina Smirnova. "Thermodynamic modeling using Extended UNIQUAC and COSMO-RS-ES models: Case study of the cesium nitrate - water system over a large range of temperatures". Fluid Phase Equilibria, janeiro de 2024, 114037. http://dx.doi.org/10.1016/j.fluid.2024.114037.

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Rahmanian, Nejat, Nejmi Söyler, Farai Munashe Wande e Hamed Hashemi. "An investigation on hydrate prediction and inhibition: An industrial case study". Canadian Journal of Chemical Engineering, 5 de junho de 2024. http://dx.doi.org/10.1002/cjce.25357.

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AbstractThis investigation reports the first study to predict natural gas hydrate formation using both Aspen HYSYS® and HydraFlash software for various gas compositions and thermodynamic inhibitors (monoethylene glycol [MEG] concentrations at 10, 20, 30, and 40 wt.% and methanol concentrations at 10 and 20 wt.%). The simulated predictions are compared with the results of the experimental data in the literature. It has been shown that HydraFlash software can accurately predict hydrate formation conditions for a given industrial case, without having to carry out costly experimental work. This work also evaluated the effect of inhibitors and it appears that inhibitor type and concentration are determined according to condition of gas composition. MEG is consequently selected as the most ideal hydrate inhibitor for the industrial case. This also was confirmed through COSMO‐RS studies in which the sigma profile and sigma potential of the considered inhibitors were obtained and presented using density functional (DFT) calculations to verify the hydrogen bonding affinities of the inhibitors to water molecules. HydraFlash was utilized to predict the dissociation conditions of hydrates under the influence of a high concentration of MEG inhibition, reaching up to 40 wt.% at 313 K and a pressure of 311.1 bar. Finally, it is shown that both software packages are quite accurate and useful tools for the prediction of hydrate for simple systems. However, HydraFlash can simulate more complex systems, including different types of salts at higher pressures. Investigation results indicate insightful guidance for accurately predicting hydrate dissociation under simulated conditions.

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Klimenko, Kyrylo, e Gonçalo V. S. M. Carrera. "QSPR modeling of selectivity at infinite dilution of ionic liquids". Journal of Cheminformatics 13, n.º 1 (26 de outubro de 2021). http://dx.doi.org/10.1186/s13321-021-00562-8.

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AbstractThe intelligent choice of extractants and entrainers can improve current mixture separation techniques allowing better efficiency and sustainability of chemical processes that are both used in industry and laboratory practice. The most promising approach is a straightforward comparison of selectivity at infinite dilution between potential candidates. However, selectivity at infinite dilution values are rarely available for most compounds so a theoretical estimation is highly desired. In this study, we suggest a Quantitative Structure–Property Relationship (QSPR) approach to the modelling of the selectivity at infinite dilution of ionic liquids. Additionally, auxiliary models were developed to overcome the potential bias from big activity coefficient at infinite dilution from the solute. Data from SelinfDB database was used as training and internal validation sets in QSPR model development. External validation was done with the data from literature. The selection of the best models was done using decision functions that aim to diminish bias in prediction of the data points associated with the underrepresented ionic liquids or extreme temperatures. The best models were used for the virtual screening for potential azeotrope breakers of aniline + n-dodecane mixture. The subject of screening was a combinatorial library of ionic liquids, created based on the previously unused combinations of cations and anions from SelinfDB and the test set extractants. Both selectivity at infinite dilution and auxiliary models show good performance in the validation. Our models’ predictions were compared to the ones of the COSMO-RS, where applicable, displaying smaller prediction error. The best ionic liquid to extract aniline from n-dodecane was suggested.

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