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Building on recent simulation work, it is demonstrated using molecular dynamics simulations of two-component fluid mixtures that the chemical contribution to the Soret effect in two-component nonideal fluid mixtures arises due to differences in how the partial pressures of the components respond to temperature and density gradients. Further insight is obtained by reviewing the connection between activity and deviations from Raoult's law in the measurement of the vapor pressure of a liquid mixture. A new parameter γ s S , defined in a manner similar to the activity coefficient, is used to characterize differences deviations from "ideal" behavior. It is then shown that the difference γ 2 S − γ 1 S is predictive of the sign of the Soret coefficient and is correlated to its magnitude. We hence connect the Soret effect to the relative volatility of the components of a fluid mixture, with the more volatile component enriched in the low-density, high-temperature region, and the less volatile component enriched in the high-density, low-temperature region. Because γ s S is closely connected to the activity coefficient, this suggests the possibility that measurement of partial vapor pressures might be used to indirectly determine the Soret coefficient. It is proposed that the insight obtained here is quite general and should be applicable to a wide range of materials systems. An attempt is made to understand how these results might apply to other materials systems including interstitials in solids and multicomponent solids with interdiffusion occurring via a vacancy mechanism. [ABSTRACT FROM AUTHOR]

A recurring misconception in some textbooks and research papers has led to an abandonment of fundamental physical laws when describing a subset of acid‐base equilibria, especially regarding the role of the solvent. In the specific case of the autoprotolysis of water, experiments and theoretical calculations prove that the Kw of water at 25 °C, 1.00×10−14, is identical to its acid ionization constant, Ka. Nevertheless, several articles have been published erroneously purporting to give theoretical proof that the Ka of water is 10−15.743 (1.81×10−16) and that the Ka of the aqueous proton (hydronium ion) is 55.3 rather than 1.00. Here we argue that using the incorrect numbers has pedagogical implications beyond those of a simple error. Arguments for the incorrect Ka and pKa values require a misapplication of Henry's law and violate long‐standing methods that use Raoult's law and the conservation of matter to describe the behavior of solutions. As a result, chemistry students may be asked to accept one set of physical principles in one course and another set in another course. Here we argue for adherence to fundamental physical laws governing solution equilibria as applied to the autoprotolysis of water and all aqueous acid base equilibria. [ABSTRACT FROM AUTHOR]

A new separation technology, three-phase crystallization (TPC), was utilized to purify acrylic acid (AA) from a binary liquid mixture comprising AA and propionic acid (PA). The solid–liquid equilibrium data of AA/PA mixture reported in the literature were adopted to recover the activity coefficients of the liquid mixture; and, subsequently, the vapor–liquid equilibrium conditions of AA/PA mixture were predicted using Raoult's law and the Wilson equations for the recovered activity coefficients. The reported solid–liquid equilibrium data and the predicted vapor–liquid equilibrium conditions were coupled to determine the three-phase transformation conditions of AA/PA mixture, which were employed to conduct the batch TPC experiments. Upon conclusion of the TPC, the yield and purity were measured to estimate the amount of the AA crystals and volume of the liquid mixture retained in the overall final product, respectively. [ABSTRACT FROM AUTHOR]

The molecular interaction volume model (MIVM) was employed to estimate the activity of each component in Zinc–Copper–Tin–Indium (Zn–Cu–Sn–In) quaternary liquid alloys at 1023 K, keeping indium content constant, i.e. xIn = 0.1, and varying molar ratios of Cu and Sn (xCu/xSn). Furthermore, the model has been used to determine the activity of each component of all sub-binary systems, namely Cu–Zn at 1200 K, Sn–Zn at 750 K, In–Zn at 700 K, Cu–Sn at 1400 K, Cu–In at 1073 K, In–Sn at 700 K, and Zn–Cu–In liquid ternary alloys at 1023 K for three molar ratios of Cu and In, i.e. xCu/xIn = 1:2, 1:1, and 2:1. We found that the activity deviations of Zn from Raoult's law transform from positive to negative as the xCu/xIn ratio changes from 1:2 to 2:1. The estimated values were analyzed with the correspondent experimental results in the case of ternary and all the binary liquid alloys. There is a notable agreement observed between theoretical forecasts and practical findings in both binary and ternary systems. This work provides a thorough thermodynamic study of the Zn, Cu, Sn, and In quaternary systems. [ABSTRACT FROM AUTHOR]

The expansion and extension of the liquid saturated vapor pressure measurement experiment involves determining the saturated vapor pressure of a liquid within a certain temperature range and using the Clausius-Clapeyron equation to obtain the molar evaporation enthalpy. Since the molar evaporation enthalpy is a function of temperature, its values differ in different temperature ranges, resulting in relatively large relative errors. The method of selecting temperature ranges based on the calculation of molar evaporation enthalpy to reduce experimental errors has not been applied in experimental teaching. In this experiment, pure water is chosen as the research object instead of organic reagents, and the average molar evaporation enthalpy of water in different temperature ranges is calculated using the method of Kirchhoff's law, which serves as a reference to determine the optimal temperature measurement range. Furthermore, the determination of the saturated vapor pressure of pure liquid is expanded to electrolyte and non-electrolyte solutions using Raoult's law, which can be linked to more theoretical teaching content. The experimental results show that the error in measuring the saturated vapor pressure of pure water within the range of 40-60 °C is small, and the molar evaporation enthalpy obtained using the experimental results is in good agreement with the calculated value, with an error of only 0.465%. Expanding this method to the determination of the saturated vapor pressure of sucrose and NaCl solutions can further verify the necessity of introducing activity coefficients in Raoult's law and the importance of studying non-ideal dilute solutions. In addition, using virtual simulation technology to demonstrate the flow of gas molecules and the change in system pressure in the static method can enhance visualization and make the experimental principle clear and easy to understand. [ABSTRACT FROM AUTHOR]

A differential scanning calorimetric technique has been used to obtain solid–liquid equilibrium temperatures for the mixtures naphthalene or biphenyl + 1-tetradecanol, or + 1-hexadecanol. All the systems show a simple eutectic point, whose final composition was determined by means of the Tamman's plots using the needed values of the eutectic heat and of the heat of melting, which are also reported. DISQUAC interaction parameters for the OH/aromatic contacts in the selected systems are given. The present experimental SLE phase diagrams are similarly described by DISQUAC and UNIFAC (Dortmund) models. However, the comparison of DISQUAC and UNIFAC results for systems involving naphthalene and shorter 1-alkanols (methanol + 1-octanol) reveals that the temperature dependence of the interaction parameters is more suitable in DISQUAC. The systems are also investigated in terms of the concentration-concentration structure factor. It is shown that the positive deviations from the Raoult's law of the studied solutions become weaker when the homocoordination decreases. [ABSTRACT FROM AUTHOR]

A novel method is introduced for estimating the degree of interactions occurring between two different compounds in a binary mixture resulting in deviations from ideality as predicted by Raoult's law. Metrics of chemical similarity between binary mixture components were used as descriptors and correlated with the Root-Mean Square Error (RMSE) associated with Raoult's law calculations of total vapour pressure prediction, including Abraham descriptors, sigma moments, and several chemical properties. The best correlation was for a quantitative structure-activity relationship (QSAR) equation using differences in Abraham parameters as descriptors (r2 = 0.7585), followed by a QSAR using differences in COSMO-RS sigma moment descriptors (r2 = 0.7461), and third by a QSAR using differences in the chemical properties of log KAW, melting point, and molecular weight as descriptors (r2 = 0.6878). Of these chemical properties, Δlog KAW had the strongest correlation with deviation from Raoult's law (RMSE) and this property alone resulted in an r2 of 0.6630. These correlations are useful for assessing the expected deviation in Raoult's law estimations of vapour pressures, a key property for estimating inhalation exposure. [ABSTRACT FROM AUTHOR]

Previous studies showed that electric fields could change the boiling point and vapor pressure of the vapor–liquid equilibrium (VLE) state of pure substances and mixtures. This is an important feature in controlling the separation of mixtures. In this paper, based on the principle of phase equilibrium, together with the formulas of chemical potential including the effect of electric field and the dielectric pressure, the Raoult's law was extended to include the effect of electric field to describe VLE of a mixture under an external electric field. The effects of electric field on VLE can be calculated by combining the extended Raoult's law and the Dalton's law of partial pressure, and then, the effect of electric field on the relative volatility can also be calculated. Numerical calculations showed that the effects of an electric field on VLE depend on both the magnitude and the direction of the electric field, and the effects become obvious until the field strength is greater than 10 7 V/m. When the direction of the electric field is parallel to the gas–liquid interface, the vapor pressure decreases; the equilibrium temperature, the mole fractions of the volatile component, and the relative volatility increase. While, when the direction of the electric field is perpendicular to the gas–liquid interface, the opposite changes in these properties appear. The shifting of the equilibrium curves caused by the electric field indicates that the electric field can cause the vapor–liquid phase transition and change the amount of the phase material. [ABSTRACT FROM AUTHOR]

At ambient pressure, MgO crystallizes in the rock salt (B1) structure, whereas ZnO crystallizes in the wurtzite structure (B4). The asymmetric miscibility gap between these two structures in the MgO–ZnO binary system narrows with increasing pressure, terminating at the wurtzite-to-rock-salt phase transition in pure ZnO, which occurs at approximately 5 GPa at 1000 ∘ C. Despite their essential simplicity, the pressure–temperature–composition (P – T – X) relations in the MgO–ZnO binary system have been sparsely studied experimentally, with disparate results that are inconsistent with available thermodynamic data. Here we report the experimental determination of the P – T – X relations of the miscibility gap from 940 to 1500 ∘ C and 0 to 3.5 GPa, which we combine with calorimetric and equation-of-state data from the literature and on the transition in endmember ZnO, to build a thermodynamic model that resolves many of the inconsistencies. The model treats the rock salt phase as an ideal solution (no excess Gibbs free energy of mixing), while in the wurtzite phase the MgO component follows Henry's law and the ZnO component Raoult's law in the range of compositions accessed experimentally. However, there is an inconsistency between the partial molar volume of wurtzite-structured MgO deduced from this model and that inferred from lattice parameter measurements by X-ray diffraction in the quenched samples. This discrepancy may be caused by unquenchable disordering of some significant fraction of the substituting Mg 2+ into normally vacant octahedral interstices of the wurtzite structure. [ABSTRACT FROM AUTHOR]

Distillation is a typical unit operation for separating liquid mixtures. The temperature-composition curve in the gas-liquid equilibrium phase diagram is important for guiding distillation operations. An ideal liquid mixture with two components was utilized as the study system in this work. We proved that the temperature-composition curve (T- x or T-y) of ideal liquid mixtures with two components is strictly monotonic, regardless of whether the saturated vapor pressure of liquid conforms to the Clausius-Clapeyron equation or Antoine equation. This means that the bubble point temperature and dew point temperature increase monotonously with the increase of lowly volatile substance content. [ABSTRACT FROM AUTHOR]

The vapor–liquid equilibrium of the fluorobenzene–polystyrene binary polymer solution at 303.15 K was measured using a static pressure device. The vapor–liquid equilibrium of the fluorobenzene–n-octane–polystyrene ternary solution in a partial concentration range under normal pressure was determined using an improved Othmer equilibrium still, in which the octane concentration was low. Three activity coefficient models, poly-NRTL, UNIQUAC, and M-UNIQUAC-LBY, were utilized to correlate the experimental data of binary and ternary solutions, and the component activities of the fluorobenzene–n-octane–polystyrene solution at 303.15 K were predicted. A mathematical model based on the Stefan flow was developed to simulate the evaporation process of composite spherical droplets. The activity predicted by the activity coefficient model was used for numerical simulations, and compared with simulations using the activity following Raoult's law. The comparative analysis revealed that simulations based on Raoult's law and activity coefficient models yielded similar results when the mass fraction of fluorobenzene exceeded 0.6. However, in the later stages of evaporation, the calculations based on Raoult's law predicted a 10% shorter drying time for fluorobenzene. The activity coefficient models provided a better approximation and exhibited similar droplet diameter shrinking behaviors to the actual evaporation process. [ABSTRACT FROM AUTHOR]

Fuel vapor concentration is a key parameter for assessing the flammability of aircraft fuel tanks. However, the current research on RP-3 (Rocket Propellant-3) fuel vapor concentration is inadequate. This study categorizes fuel components by the number of carbon atoms and utilizes Raoult's law to estimate the gas–liquid equilibrium relationship of each constituent element under equilibrium conditions. The equilibrium-state model is experimentally validated, and the differences in the constituents and fuel vapor concentrations of RP-3 and Jet-A (Jet Fuel-A) fuels are analyzed. In addition, an empirical correlation between the overall hydrocarbon concentration of RP-3 fuel vapor and the temperature and pressure in the equilibrium state is established, providing a theoretical basis for determining RP-3 fuel vapor concentration in related investigations. Furthermore, a transient prediction model of fuel vapor concentration is developed using the lumped parameter approach that considers the heat exchange among the fuel, gas, wall, and environment. The model's accuracy is confirmed by comparing it to existing literature. Then, the temperature and fuel vapor concentration variation patterns in the fuel tank are calculated and evaluated under two typical flight scenarios. The results show a significant difference between the calculated fuel vapor concentration values obtained through equilibrium-state and transient models. Therefore, in the design of fuel vapor catalytic inerting systems, it is crucial to consider both the equilibrium and transient fuel vapor concentration values rather than relying solely on the former. Throughout the flight envelope, gas phase and fuel phase temperatures in RP-3, Jet-A, and C10H22 fuel tanks exhibit minimal differences. However, significant variations in fuel vapor concentration exist depending on the flight state and envelope. Hence, regarding RP-3 as equivalent to C10H22 is inappropriate. Additionally, fuel vapor concentration is a more suitable metric than fuel temperature for assessing fuel tank flammability. [ABSTRACT FROM AUTHOR]

Although non‐aqueous phase liquids (NAPLs) are typically released to the environment as complex mixtures, most investigations of subsurface remediation focus on single contaminants and ignore the potential effects of co‐constituents on mass recovery and groundwater plume evolution. In this study, we investigate the dissolution and micellar solubilization of binary NAPL mixtures in completely mixed batch reactors and heterogeneous aquifer cells using a commercially‐available nonionic surfactant, Tween® 80. Micellar solubilization of trichloroethene (TCE), tetrachloroethene (PCE), decane, and dodecane measured in batch studies containing binary mixtures of TCE/PCE or decane/dodecane exhibited nonideal behavior that could not be predicted using Raoult's law. For a mixed PCE/decane NAPL, micellar solubilization of PCE was approximately 40% less than predicted, while decane was over 100% greater, which was attributed to expansion of the micelle core. In two aquifer cells containing different size fractions of quartz sand and low‐permeability lenses, the initial NAPL (1:1 TCE:PCE) saturation distributions resulted in "pool" fractions (PFs) of 0.88 and 0.36. During the initial water flood, the greater aqueous solubility of TCE relative to PCE resulted in preferential removal of TCE from the source zone. However, when a 4% (wt) solution of Tween® 80 was introduced, preferential micellar solubilization of PCE relative to TCE resulted in enhanced removal of PCE, with TCE mass discharge reduced from 97% and 90% and PCE mass discharge reduced from 79% and 53%. The observed relationships between mass discharge and mass removal indicating that plume evolution is strongly influenced by the initial NAPL saturation distribution, changes in the mole fraction of NAPL constituents, and regions of high NAPL saturation that persist over time. [ABSTRACT FROM AUTHOR]

In the current research, the binary solution containing ionic liquid (IL), 1-ethyl-1-methylmorpholinium dimethyl phosphate ([C1C2MOR][DMP]), 1-ethyl-1-methylpiperidinium dimethyl phosphate ([C1C2PIP][DMP]), or N,N,N-triethyl-N-methylammonium dimethyl phosphate ([N1,2,2,2][DMP]) with ethanol are investigated as new working fluids for absorption refrigeration technology. The IL was mixed with ethanol, which was considered as a refrigerant. Experimental (vapor + liquid) phase equilibria (VLE) of these binary systems were measured by an ebulliometric method within a temperature range from T = (328.15 to 348.15) K with an increment of 10 K and pressures up to 90 kPa. Experimental VLE data were correlated using non-random two-liquid (NRTL) within the maximum average relative deviation of 0.45%, which confirms the effectiveness of using such a model for calculations. Each of the proposed binary systems exhibit a negative deviation from Raoult's law, which is a very important characteristic for working pairs used in absorption heat pumps or absorption refrigerators. From a technological point of view, measurements of physicochemical properties play an important role. In this research, liquid density and dynamic viscosity were determined at temperatures from T = (293.15 to 338.15) K at ambient pressure over the whole concentration range. These properties were correlated using empirical equations. From experimental density data, the excess molar volumes were determined and correlated using the Redlich–Kister type equation. Ionic liquid: [C1C2MOR][DMP] and [C1C2PIP][DMP] were synthesized and characterized using NMR analysis. The thermophysical characterization of pure ILs, including glass transition temperature (Tg) and heat capacity at the glass transition temperature (ΔgCp), was determined using the differential scanning calorimetry technique (DSC) at atmospheric pressure. In this work, the combination of basic studies on the effect of the cation structure of an ionic liquid on the properties of their solutions with ethanol and the possibility of future application of the tested systems in a viable refrigeration system are presented. [ABSTRACT FROM AUTHOR]

In the reflow process, the thermal decomposition of flux with different thermal stability will lead to different residues on printed circuit board assemblies, which will affect the reliability of solder joints. As an essential part of the flux, the solvent is one of the main factors affecting the thermal stability of flux. This paper systematically investigated the effect of solvents on the thermal stability of flux and the corresponding paste. Thermogravimetric analysis and differential scanning calorimetry (TGA–DSC) curves of various solvents showed that the end temperature of weight loss of each solvent is significantly 80–90 °C lower than their boiling points. By mixing solvents and adding other additives, the thermal stability of mixed solvents and flux enhanced due to Raoult's law. Thus, TGA–DSC curves provided a clear indicator than the boiling point to guide the selection of solvents in the development of solder paste formulation. Also, TGA–DSC curves of flux showed two distinct thermal decomposition stages: solvent volatilization dominated weight loss and then thermal decomposition of rosin and other additives dominated weight loss. In addition, the real-time in situ hot plate soldering experiment and slump test of solder pastes showed that different thermal stability solvents in flux affect the reflow behaviors of solder paste, which is mainly reflected in collapse performance. [ABSTRACT FROM AUTHOR]

Dense non-aqueous phase liquids (DNAPLs) are considered as priority pollutants in groundwater systems due to their low solubility and high toxicity even at low concentrations. The impact of their accidental release is irreversible as they mix with groundwater through dissolution such that complete remediation of the aquifer is nearly impossible. In this paper, the current status of research and recent developments in the experimental, analytical and mathematical approaches to study the dissolution of multi-component DNAPL compounds in the saturated, homogeneous/heterogeneous porous media are summarised. It is observed that most of the earlier investigations have been confined to single-component dissolution either in lab-scale or in-situ studies. The existing mass transfer correlations are insufficient to estimate the dissolution rate of DNAPLs in a multi-component system where the velocity and non-aqueous phase liquids saturation are differently influenced by the aquifer heterogeneity. Considering the variability in the distribution pathways, a realistic quantification of the morphology and surface area of DNAPLs is quite challenging. Based on the insights from the recent literature, it is envisaged that a combination of solubility enhancement and remobilisation techniques can be further expanded to optimally remediate the contaminated sites. [ABSTRACT FROM AUTHOR]

Phase equilibrium K values are either estimated with empirical correlations or rigorously calculated based on fugacity values determined from an equation of state. There have been several empirical analytical equations such as Raoult's Law, the Hoffman Equations (Hoffman A, Crump J, Hocott C. Equilibrium constants for a gas condensate system. J Petrol Technol 1953;5:1–10) and their modifications and the well-known Wilson Equation (Wilson G. A modified Redlich–Kwong equation of state applicable to general physical data calculations. In: AIChE National Meeting Paper15C, May 4–7, Cleveland, OH; 1969). along with several modifications. This work presents a new modification of the Wilson Equation for estimating phase equilibrium K values, predominantly for light hydrocarbon mixtures. The modification is based on correlating a subset of a database of K values, established from convergence pressure data. Results show the method to accurately correlate and predict the K value data, within 10% on average. Moreover, the predicted K factors provide remarkable results for such a simple model when used in a variety of phase equilibrium calculations. The results also show that the new model compares favorably with existing empirical analytical methods. Such a model would provide excellent initial estimates for rigorous thermodynamic calculations. [ABSTRACT FROM AUTHOR]

The article presents materials science research study on how Aluminum formate, an earth-abundant material for CO2 capture. Topics include combination of gas adsorption and gas breakthrough measurements show that the metal-organic framework, Al(HCOO)3 (ALF), which can be made inexpensively from commodity chemicals; and preferential adsorption of CO2 is a size-selective separation that depends on the subtle difference between the kinetic diameters of CO2 and nitrogen gas (N2).

The impact of molecular level surface chemistry for aerosol water-uptake and droplet growth is not well understood. In this work, spherical, nonporous, monodisperse polystyrene latex (PSL) particles treated with different surface functional groups are exploited to isolate the effects of aerosol surface chemistry for droplet activation. PSL is effectively water insoluble and changes in the particle surface may be considered a critical factor in the initial water uptake of water-insoluble material. The droplet growth of two surface modified types of PSL (PSL-NH 2 and PSL-COOH) along with plain PSL was measured in a supersaturated environment with a Cloud Condensation Nuclei Counter (CCNC). Three droplet growth models – traditional Köhler (TK), Flory–Huggins Köhler (FHK) and the Frenkel–Halsey–Hill adsorption theory (FHH-AT) were compared with experimental data. The experimentally determined single hygroscopicity parameter, κ , was found within the range from 0.002 to 0.04. The traditional Köhler prediction assumes Raoult's law solute dissolution and underestimates the water-uptake ability of the PSL particles. FHK can be applied to polymeric aerosol; however, FHK assumes that the polymer is soluble and hydrophilic. Thus, the FHK model generates a negative result for hydrophobic PSL and predicts non-activation behavior that disagrees with the experimental observation. The FHH-AT model assumes that a particle is water insoluble and can be fit with two empirical parameters (AFHH and BFHH). The FHH-AT prediction agrees with the experimental data and can differentiate the water uptake behavior of the particles owing to surface modification of PSL surface. PSL-NH 2 exhibits slightly higher hygroscopicity than the PSL-COOH, whereas plain PSL is the least hygroscopic among the three. This result is consistent with the polarity of surface functional groups and their affinity to water molecules. Thus, changes in AFHH and BFHH can be quantified when surface modification is isolated for the study of water-uptake. The fitted AFHH for PSL-NH 2 , PSL-COOH, and plain PSL is 0.23, 0.21, and 0.18 when BFHH is unity. To simplify the use of FHH-AT for use in cloud activation models, we also present and test a new single parameter framework for insoluble compounds, κFHH. κFHH is within 5 % agreement of the experimental data and can be applied to describe a single-parameter hygroscopicity for water-insoluble aerosol with surface modified properties. [ABSTRACT FROM AUTHOR]

While phase equilibria at conditions on Pluto's surface have been studied, the fate of the equilibria in the lower atmosphere as the altitude increases has not. In this study, the gravitational effect is included in the thermodynamic modelling so that not only the deposition point can be located, but also the vertical pressure and density profiles below the deposition point can be determined, along with the corresponding compositional profiles in the equilibrium phases. The non-ideality of vapour-solid phase equilibria at low pressures and temperatures is also discussed for Pluto's applications to allow for more accurate calculations if a conventional method, such as modified Raoult's law, is used. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents (DES) are compounds of a hydrogen bond donor (HBD) and a hydrogen bond acceptor (HBA) that contain a depressed melting point compared to their individual constituents. DES have been studied for their use as carbon capture media and biogas upgrading. However, contaminants’ presence in biogas might affect the carbon capture by DES. In this study, conductor-like screening model for real solvents (COSMO-RS) was used to determine the effect of temperature, pressure, and selective contaminants on five DES’ namely, choline chloride-urea, choline chloride-ethylene glycol, tetra butyl ammonium chloride-ethylene glycol, tetra butyl ammonium bromide-decanoic acid, and tetra octyl ammonium chloride-decanoic acid. Impurities studied in this paper are hydrogen sulfide, ammonia, water, nitrogen, octamethyltrisiloxane, and decamethylcyclopentasiloxane. At infinite dilution, CO2 solubility dependence upon temperature in each DES was examined by means of Henry’s Law constants. Next, the systems were modeled from infinite dilution to equilibrium using the modified Raoults’ Law, where CO2 solubility dependence upon pressure was examined. Finally, solubility of CO2 and CH4 in the various DES were explored with the presence of varying mole percent of selective contaminants. Among the parameters studied, it was found that the HBD of the solvent is the most determinant factor for the effectiveness of CO2 solubility. Other factors affecting the solubility are alkyl chain length of the HBA, the associated halogen, and the resulting polarity of the DES. It was also found that choline chloride-urea is the most selective to CO2, but has the lowest CO2 solubility, and is the most polar among other solvents. On the other hand, tetraoctylammonium chloride-decanoic acid is the least selective, has the highest maximum CO2 solubility, is the least polar, and is the least affected by its environment.

The purpose of this work is to provide consistent experimental measurements on the vapor–liquid equilibria (VLE) at the isobaric conditions of 50.00, 75.00 and 94.00 kPa, as well as experimental determinations of the liquid mass densities, the surface tensions and the dynamic viscosities at 298.15 K and 101.3 kPa of the methyl butyrate + tert -butanol binary system within the whole composition range. For these goals, a Gillespie-type cell is used to carry out the VLE measurements, whereas an oscillating densimeter, a maximum differential bubble pressure tensiometer, and a rotating viscometer are used to quantify the remaining physical properties. The thermodynamical quality of the reported VLE data is validated by Fredenslund's consistency test. Based on the VLE results, this zeotropic binary mixture exhibits a positive deviation from Raoult's law. Furthermore, the validated data are correlated with three activity coefficient models (i.e. , Wilson, NRTL, and UNIQUAC), with the Wilson equation being the most accurate one. Excess volumes, surface tensions, and liquid viscosities data are correlated by Redlich–Kister-type expansions, and the Grunberg–Nissan equation is also applied to viscosity modeling. The calculated excess volumes display a positive deviation from the ideal solution model. Regarding surface tensions, this system showcases both negative and positive deviation, althouhg slight, from the linear behavior while exhibiting the linear trend at a molar fraction of methyl butyrate of 0.758. In addition, this bimodal deviation is adequately predicted by the Chunxi model with the Wilson parameters determined from the VLE data. Finally, the dynamic viscosities data obey a strictly monotonic mole dependence predicted by Eyring's theory, although without high accuracy. These results also reflect some interesting phenomena related to competitive association effects, which are discussed. [Display omitted] • Vapor-Liquid Equilibria for the methyl butyrate + tert -butanol binary system. • Liquid mass densities for the methyl butyrate + tert -butanol binary system. • Surface tensions and viscosities for the methyl butyrate + tert -butanol binary system. • A full predictive approach is applied for modeling surface tensions, and viscosities. [ABSTRACT FROM AUTHOR]

Modeling and simulation of a distillation column are very important in many chemical industries where ever it requires separation or purification of a liquid mixture into its pure components. Particularly in the context of improving efficiency, process scale-up, intensification and control it requires a validated model. In this work, both experimental results and simulation results are obtained. A batch distillation equipment that consists of a reboiler, a packed column, and a top condenser is used to distill a mixture of benzene and toluene with various heat inputs to the reboiler. The distillation process in the column is modeled by an evaporation rate-based approach using Raoult’s law for driving force. This particular feature is different from the stage-wise equilibrium model. The evaporation mass transfer coefficients are obtained for benzene and toluene in lab-scale apparatus. The material balance equations for the two components are solved using a finite difference method. The distillate compositions at total reflux obtained from experiments and the simulations are compared for validating of model proportionally. Further insights are obtained in regard to throughput and distillation efficiency.