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The aqueous solubilities, the octanol-water partition coefficients and the vapor pressures of two food contaminants (dimethyl phthalate-DMP and butyl benzyl phthalate-BBP) have been determined in this work. The aqueous solubility measured by the dynamic saturation method [298.15–328.15 K] were in the order of 10−4 mol fraction for DMP and 10−7 for BBP. The octanol-water partition coefficient is measured by using the ‘shake-flask’ method at 298.15 K. It is found that the BBP molecule is highly hydrophobic. The vapor pressure measurements carried out with the dynamic gas saturation method between 313.15 and 423.15 K, were validated with DMP vapor pressure measurements by using a static apparatus. The vapor pressures of DMP ranged from 1.4 to 1668 Pa for temperatures between 313.15 and 423.15 K, while BBP exhibits lower vapor pressures ranging from 0.014 Pa at 343.15 K to 24 Pa at 423.15 K. The experimental data determined in this work are compared with calculated properties issued from different thermodynamic models (UNIFAC, UNIQUAC, NRTL, COSMO-SAC dsp). It is found that the UNIQUAC and NRTL models can well describe the experimental aqueous solubility, while larger deviations were found for UNIFAC and COSMO-Sac dsp. The COSMO-SAC dsp model can better predict the octanol-water partition coefficient of the studied molecules than the UNIFAC model.

The vapour pressures of the pure components 3,3-diamino-N-methyldipropylamine (DNM) and N,N,N′,N′′,N′′-pentamethyldiethylenetriamine (PMDETA) along with the binary mixtures (DNM + water) and (PMDETA + water) were measured by means of a static apparatus at temperatures between (283 and 363) K. The data were correlated with the Antoine equation. From these data, excess Gibbs functions (GE) were calculated for several constant temperatures and fitted to four order Redlich-Kister equation using the Barker method. The binary system (DNM + water) exhibits negative deviations in GE values calculated from the vapour pressure data for all investigated temperatures and over the whole composition range. The (PMDETA + water) binary mixture shows a sinusoidal shape for GE at 283.15 K

Energy, fuel and chemical production like syngas from biomass is increasingly attracting interest in the world, with increasing potential to replace conventional fossil fuels in the energy market. Biomass gasification has been studied widely as an efficient and sustainable technology for the syngas production. Thus, raw syngas contains a significant quantities of undesirable impurities known as syngas contaminants, especially tar which can cause major problems to the gasification process; therefore it is crucial to eliminate the generated tar in this process by one of the most promising method “the tar scrubbing oil” using a suitable extracting solvent. With this aim, an experimental study of the liquid–liquid equilibrium of the ternary systems of water + solvent (methyl oleate-biodiesel solvent) + model mixtures of tar (naphthalene, phenanthrene and anthracene) that are presented in the raw syngas was conducted at 303.2 K, 323.2 K and 343.2 K. Due to the low solubility of the studied model molecule of tars in the aqueous phase, an extraction of these analytes (naphthalene, phenanthrene and anthracene) from the aqueous phase was performed by an auxiliary solvent (dichloromethane), in which was dissolved an internal standard (hexadecane) before analysis in the GC–MS using the internal standard technique. A control analysis was systematically performed in order to ensure that all of the solute was extracted from the aqueous phase. As for the analysis of the organic phase, it was carried out in the GC–MS using the internal standard technique without any prior extraction. Coulometric Karl Fischer (KF) titration was used to quantify water in the organic phase. Partition coefficient and selectivity of the biodiesel solvent were also discussed. This work is followed by a modeling study of the same systems using the nonrandom two-liquid (NRTL) and UNIQUAC (universal quasichemical) models.

The vapor pressures of two binary systems ethyl dodecanoate (1) + n-dodecane (2) and ethyl octanoate (1) + n-dodecane (2), were measured by means of a static apparatus at temperatures between 373.15 K and 453.15 K. The data were correlated with the Antoine equation. From these data, the molar excess Gibbs energies GE were obtained with Barker’s method and fitted to the Redlich-Kister equation. The binary mixture (ethyl octanoate (1) + n-dodecane (2)) exhibits maximum azeotropic behavior. Positive values of the excess Gibbs energy are obtained for all the investigated constant temperatures and over the whole composition range. The data were also correlated by using Wilson equation and good results were obtained in the prediction of the total pressure and thermodynamic excess properties; however deviations were observed with respect to the experimental and predicted GE, using modified UNIFAC (Dortmund) group contribution model. Additionally, the NRTL model was applied to regress the experimental GE. The investigated systems were successfully represented by the NRTL model.

In this work, we studied the aqueous solubility, vapor pressures of dibutylphthalate (DBP) and di-isobutylphthalate (DIBP) as a function of temperature between 298.15 and 328.15 K and between 313.15 and 423.15 K respectively. The octanol-water partition coefficient was measured at 298.15 K using shake-flask method. For aqueous solubility, measurements were carried out using the dynamic saturation method and values ranges in 10−7 mol fraction with a relative higher solubility for DIBP regarding DBP. Solubility results are in good agreement with the octanol-water partition coefficient measurement showing that DBP is more hydrophobic than its isomer DIBP. For vapor pressure, after an interlaboratory validation step using static method performed with DBP in a temperature range between 381 and 421 K, measurements for both compounds DBP and DIBP using the gas saturation method presented a standard relative deviation lower than 2% and values ranged from 10−2 and 102 Pa. By combining vapor pressure and solubility results, we calculated Henry's law constant and air-water partition coefficient and showed an important deviation between the two isomers even at low temperature.

International audience; The vapor pressures of the pure components 3-aminopropylmethylamine (MAPA), 3-aminopropyldimethylamine (DMAPA) and N,N-diethyl 1,3-propanediamine (DEAPA) along with the binary mixtures (MAPA + water), (DMAPA + water) and (DEAPA + water) were measured by means of a static apparatus at temperatures between (273 and 363) K. The data were correlated with the Antoine equation. From these data, excess Gibbs functions (GE) were calculated for several constant temperatures, and fitted to a three parameters Redlich–Kister equation using the Barker’s method. Additionally, the NRTL and UNIQUAC models have been used for the correlation of the total pressure.

International audience; New solubility data of binary and ternary systems involving ethylene glycol (or MEG), water and n-alkanes (hexane, heptane, octane, nonane, undecane, dodecane and hexadecane) under atmospheric pressure at three temperatures 283.15, 303.15 and 333.15 K are reported. The reported values are original except for binary systems where some points were found in the literature for comparison. The non-random two-liquid (NRTL) were used to correlate the experimental data of the binary mixtures. The interaction parameters obtained with the experimental binary systems were used to predict the ternary systems.

International audience; The vapor pressures of (1,3-pentanediamine + water), or (1,5-diamino-2-methylpentane + water) binary mixtures, and of pure 1,3-pentanediamine or 1,5-diamino-2-methylpentane components were measured by means of a static device at temperatures between (273 and 363) K. The data were correlated with the Antoine equation. From these data excess Gibbs functions (GE) were calculated for several constant temperatures and fitted to a three order Redlich–Kister equation using the Barker’s method. The (1,3-pentanediamine + water) or (1,5-diamino-2-methylpentane + water) binary systems exhibit negative deviations in GE for all investigated temperatures over the whole composition. Additionally, the NRTL UNIQUAC and Modified UNIFAC (Do) models have been used for the correlation or prediction of the total pressure.

To determine the octanol–water partition coefficient (log Kow or log D), a microfluidic method is developed to reduce time and coast of analyze. A double Y serpentine microfluidic chip is fabricated used soft lithography facilities. To generate a biphasic parallel flow, hydrophilic microchannels walls are generated by oxygen plasma treatment. Epifluorescence microscopy is used to measure the intensity of fluorescence molecules in microchannel. Using microfluidic parallel diluter this intensity show a strong linear correlation with molecule concentration in solution. The equilibrium between phases is reached in less than 5 s. To validate this microsystem, we have determined the log D of fluorescein natrium molecule. The obtained results compare well with previous measurements using traditional shake-flask or microfluidic drops flow methods, with a relative difference to the literature less than 3%. Rapid microfluidic partition coefficient determination is useful for studying liquid–liquid partition of organic pollutant.

International audience; In this work (vapour + liquid) equilibrium (VLE) measurements were performed on binary systems of the ionic liquid 1-ethyl-3-methylimidazolium thiocynate [EMIM][SCN] with thiophene or pyridine at pressures close to the atmospheric pressure using a static device at temperatures between 273 K and 363 K. Experimental data were correlated by the PC-SAFT EoS. The binary interaction parameters kij were optimised on experimental VLE data. The results obtained for the two binary mixtures studied in this paper indicate that the PC-SAFT EoS can be used to represent systems containing ionic liquids.

International audience; Solubility of carbon dioxide (CO2) acid gas in aqueous solutions in 2.5 mol/l tertiary amines, such as 2-(2-(dimethylamino) ethoxy) ethanol [DMAEOE], 3-dimethyl amino-1-propanol [DiMAP], 1,2-bis (dimethyl amino) ethane [TEMED], pyridine and methyl-4-morpholine has been measured at [313 and 353] K, and over the pressure range (0-200) kPa, using a specifically built apparatus based on the static method. The vapor pressures and the densities of these aqueous solutions, also, have been measured by a static method and picnometry, respectively. For validation of the experimental procedure, solubility of acid gas CO2 in 2.5 mol/l aqueous solutions of mono-ethanolamine (MEA) and 2-amino-2-methyl-1-propanol (AMP) has been measured at 313.15 K. The experimental solubility results are presented in the form of the partial pressure of CO2 versus the mole ratio α (mol CO2/mol amine), at each temperature. The solubility of gas CO2, in all the investigated aqueous amines, decreases with an increase of the temperature and increases with increasing partial pressure of CO2 gas at a given temperature. The values of the solubility of CO2 gas are in the following sequence: Pyridine < Methyl morpholine < DMAEOE < TEMED < DiMAP.

International audience; The vapor pressures of (4-ethylmorpholine + water), (1,2-dimethylisopropylamine + water), (N,N-dimetylethanolamine + water) binary mixtures, and of pure 4-ethylmorpholine, 1,2-dimethylisopropylamine and N,N-dimethylethanolamine components were measured by means of two static devices at temperatures between {273 (or 283) and 333 (or 363)} K. The data were correlated with the Antoine equation. From these data excess Gibbs functions (GE) were calculated for several constant temperatures and fitted to a fourth-order Redlich-Kister equation using the Barker's method. The (4-ethylmorpholine + water), and (1,2-dimethylisopropylamine + water) binary systems show positive azeotropic behavior. The aqueous solutions of 4-ethylmorpholine and 1,2-dimethylisopropylamine exhibit positive deviations in GE for all investigated temperatures over the whole composition, where the aqueous solution of N,N-dimetyhlethanolamine show a S shape for GE for (273.15 < T < 313.15) K. Additionally, the Wilson, NRTL or UNIQUAC models have been used and quite good results were obtained in the prediction of the total pressure.

International audience; The vapor-liquid equilibria of the pure components, 2,5-dimethyl furan (DMF), 1-butanol, 2-butanol, and 1-hexanol along with the binary mixtures (2,5-dimethyl furan + 1-butanol), (2,5-dimethyl furan + 2-butanol), and (2,5-dimethyl furan + 1-hexanol) were investigated experimentally by means of a static apparatus at temperatures between 313 and 393 K. The vapor pressures of the pure components were correlated with the Antoine equation. The experimental data of the mixtures were reduced by Barker method using a third-order Redlich-Kister equation. The calculated excess Gibbs functions, GE, exhibit positive deviations for all investigated temperatures and over the whole composition range. The NRTL and UNIQUAC models have also been used and good results were obtained in the prediction of the total pressure. Highlights Vapor pressures of 2,5-dimethyl furan + 1-butanol, + 2-butanol or +1-hexanol. The investigated temperatures are 313 K and 393 K. (2,5-dimethyl furan + 1-hexanol) system shows maximum azeotropic behavior. The three binary systems exhibit positive deviations in GE. The NRTL, UNIQUAC and UNIFAC models have been used.

International audience; The vapour pressures of (sec-butylamine + water), (cyclohexylamine + water) binary mixtures, and of pure sec-butylamine and cyclohexylamine components were measured by means of two static devices at temperatures between 293 (or 273) K and 363 K. The data were correlated with the Antoine equation. From these data, excess Gibbs functions (GE) were calculated for several constant temperatures and fitted to a fourth-order Redlich-Kister equation using the Barker's method. The (cyclohexylamine + water) system shows positive azeotropic behaviour for all investigated temperatures. The two binary mixtures exhibit positive deviations in GE for all investigated temperatures over the whole composition range. Highlights Vapour pressures of sec-butylamine or cyclohexylamine and their aqueous solutions. The investigated temperatures are 273 K and 363 K. The (cyclohexylamine + water) mixture shows positive azeotropic behaviour. The (sec-butylamine + water) or (cyclohexylamine + water) exhibit positive GE.

Post combustion Carbon Capture (PCC) and Storage technology is viewed as an efficient solution to reduce CO2 emissions. In PCC, an amine in aqueous solution can be used to selectively capture CO2 from a flue gas to usually achieve a targeted 90% CO2 removal. However, using a 30% wt solution of MonoEthanolAmine (MEA), 3.7 GJ/tCO2 is required to release the carbon dioxide from the solvent, which is not satisfactory either from the economical point of view, or from the environmental point of view. One alternative to improve the process is to tune the chemical properties of the solvent in order to obtain a higher cyclic capacity of absorption than the one of 30% wt MEA solution. This allows to reduce the total liquid flow rate in the CO2 capture plant, and thus the energy requirement for a given CO2 removal. Another alternative, which can be combined with the first alternative, is to tune the physical properties of the solvent in order to obtain a liquidliquid phase separation in the process. In this class of DMXTM solvents, the CO2 captured concentrates in one of the two phases and only a portion of the total flow rate has to be sent to the stripper and thus, the energy requirement for a given amount of CO2 captured is reduced. In this work, we present liquid-vapor and liquid-liquid equilibrium data obtained with different DMXTM solvents along with the corresponding estimations of the potential reduction of the liquid flow rate in the stripper.

The vapour pressures of (2-amino-2-methyl-1-propanol (AMP) + water), (N-benzylethanolamine + water), or (3-dimethylamino-1-propanol + water) binary mixtures, and of pure AMP and 3dimethylamino-1-propanol components were measured by means of two static devices at temperatures between 283 K and 363 K. The data were correlated with the Antoine equation. From these data, excess Gibbs functions (G(E)) were calculated for several constant temperatures and fitted to a fourth-order Redlich-Kister equation using the Barker's method. The (2-amino-2-methyl-1-propanol (AMP) + water) binary mixture exhibits negative deviations in G(E) (at T < 353.15 K) and a sinusoidal shape for G(E) for the higher temperatures over the whole composition range. For the aqueous N-benzylethanolamine solution, a S shape is observed for the G(E) for all investigated temperatures over the whole composition range. The (3-dimethylamino-1-Propanol + water) binary mixture exhibits negative deviations in G(E) (at T < 293.15 K), positive deviations in G(E) (for 293.15 K < T < 353.15 K) and a sinusoidal shape for G(E) for the higher temperatures over the whole composition range.

The vapour pressures of the binary systems 1,2-dichloroethane + diethyl ether, +diisopropyl ether or +methyl 1,1-dimethylethyl ether and of the four pure components are measured by a static method in the temperature range from 273 to 354 K. The isoplethal T–P data are reported and correlated with the Antoine equation. Interpolated data are also reported. Excess molar Gibbs energies, GE, are calculated for several constant temperatures, taking into account the vapour phase imperfection in terms of the second virial coefficients, and are fitted to the Redlich–Kister equation. The experimental VLE data are analysed in terms of the Modified UNIFAC (Do) model.

This paper mainly concerns the thermodynamic properties of dissolution for 1-naphtol N-methylcarbamate (or carbaryl), which will lead to the Heidman's thermodynamic equation application for this molecule dissolution in pure, mineral and Mediterranean sea water. In fact, the prediction of the transport and fate of hydrophobic organic chemicals in the environment requires the knowledge of their physical and chemical properties, the most important of which is their aqueous solubility. The aim of this work is to set the dynamic saturation method that enables us to measure the aqueous solubilities of organic compounds. Those suffer from lack of data due to solubility below 10−3 in mole fraction. The carbaryl aqueous solubility study, over a range of temperature between 273.15 K and 318.15 K, was carried out in three different aqueous solvents: pure, mineral, and Mediterranean sea water. An analytical procedure was set by means of GC–FID and optimized in order to quantify the carbaryl by an internal calibration method. The carbaryl showed an aqueous solubility ranging from 3 × 10−6 to 3.5 × 10−5 in mole fraction. A salting out effect was well observed and indicated in the solubility data obtained. The solubility values acquired form this method were then used to calculate thermodynamic properties such as Gibbs free energy (ΔsolG°), molar enthalpy of dissolution (ΔsolH°), molar entropy of dissolution (ΔsolS°).

Vapor pressures of four pure pentaerythritol esters, PE, pentaerythritol tetrapentanoate, pentaerythritol tetraheptanoate, pentaerythritol tetranonanoate and pentaerythritol tetra 2-ethylhexanoate were measured between 334 and 476 K in a recently developed gas saturation apparatus. The experimental vapor pressure values for the four polyolesters range from 5.6 × 10−5 Pa to 0.94 Pa. These data together with density values were used to determined SAFT and PC-SAFT characteristic parameters. The linearity of molecular parameters for both models with the molecular weight permits to interpolate and extrapolate these parameters for pentaerythritol ester with linear chains. For pentaerythritol esters with ethyl-alkanoic chains, the parameters of SAFT and PC-SAFT have been estimated assuming that the slope of these straight lines is the same for PEs with linear chains that for PE with branched chains. This procedure was used to predict density of commercial POEs, estimating the molecular weight when it is not available from the viscosity at 313.15 K. PC-SAFT gives better performances than SAFT to predict density data for these four compounds at high pressures and for other PEs at atmospheric pressure. Furthermore, characteristic parameters for Soave-Redlich-Kwong and Peng Robinson EoSs were also estimated from the experimental vapor pressures and literature density values.

Experimental vapor pressures were developed for alkylsulfides (di-butylsulfide, di-sec-butylsulfide, di-hexylsulfide, di-octylsulfide, di-tert-butylmethylsulfide) and arylsulfides (ethylphenylsulfide, di-phenylsulfide, di-benzylsulfide, benzylphenylsulfide) from 1 Pa to 63 kPa. The vapor pressures of these compounds were also calculated using a Peng-Robinson-type equation of state. Each component was characterized by three parameters: the normal boiling temperature, the pseudocovolume and the shape parameter which are calculated by a Bondi-like group contribution method. The proposed approach yield to a good representation of the vapor pressures of the different compounds.

The aim of this study was to determine experimentally the vapour pressures of aroma compounds at various temperatures, especially at negative ones. The aroma compounds were: acetone, 2-butanone, 2-hexanone, 2-octanone, ethyl acetate, ethyl butanoate, ethyl hexanoate, n-hexanal, n-hexanol and γ-hexalactone. The technique used was a static device where vapour pressure was measured at equilibrium. The temperatures of analysis varied from −40 to 25 °C. Volatility of a pure compound depends on characteristics such as length of the aliphatic chain, the functional group and temperature. Among an homologous series, volatility increases when the aliphatic chain decreases and when temperature increases. For aroma compounds which have the same number of carbon atoms in their structure, volatility depends not only on either temperature or molecular weight, but also on the functional group of the molecule. At a given temperature volatility of compounds which have the same number of carbon atoms in their structure, decreases as follows: ester> ketone> aldehyde> alcohol> lactone.

Experimental data are reported of excess molar volumes and excess molar enthalpies of binary mixtures of N , N , N ′, N ′-tetramethyl-1,3-butanediamine + n -heptane or + cyclohexane at 298.15 K. The vapour pressures of the same binaries were also measured by a static method between 273.15 and 363.15 K at 10 K intervals. The molar excess Gibbs energies, calculated from the vapour liquid equilibrium data, and the molar excess enthalpies are used to test the applicability of group-contribution (DISQUAC) model. In particular, the possibility is tested to analyse the intramolecular effects (proximity effect).

Vapor pressures above liquid and solid phases and enthalpies of vaporization and sublimation were established in a wide temperature range for three hydrocarbons that are among the model compounds for higher boiling petroleum fractions and coal liquids. The recommended values were obtained by combining the data from vapor pressure measurements with the calorimetric measurements of heat capacities and heats of fusion, and with additional data on ideal gas heat capacities. The recommended values are given for both the vapor–solid (v–s) and vapor–liquid (v–l) equilibria in terms of the parameters of the Cox vapor pressure equation allowing calculations from 223 to 623, 533 and 583 K for 1-phenyldodecane, adamantane and (5α)-cholestane, respectively.

In this work, the experimental vapor pressures of four amines 1,2-bis(dimethylamino)ethane, 1-methylmorpholine, 1,2-bis(2-aminoethoxy)ethane and N-benzylethanolamine using a static apparatus are reported. The temperature range is comprised between 273.18 and 364.97 K and the pressure range between 0.782 Pa and 333 kPa. The molar enthalpies of vaporization at 298.15 K were calculated from Clausius–Clapeyron equation fitted on the experimental results.

Vapour pressures were measured using the static method for thirteen secondary and tertiary alcohols over the pressure range of 0.2 to 2000 Pa. Antoine equations are given in addition to the experimental values. A modified Peng–Robinson equation of state in which the covolume and attractive term were calculated by a group-contribution method was developed for primary alcohols. The proposed model leads to good results and is applied to secondary and tertiary alcohols.

Recommended data on vapour pressures above liquid and solid phases and enthalpies of vaporisation and sublimation were developed for six basic polycyclic hydrocarbons and dibenzothiophene which are considered as model compounds for petroleum fractions and coal liquids. The recommended values are presented in the temperature range where reliable experimental data are available, mostly from about 220 K to about 550 K. The data are given in terms of parameters of the Cox vapour pressure correlation equation which has an identical form for the description of both vapour–solid and vapour–liquid equilibria. Equation parameters were developed by a simultaneous multi-property correlation of new experimental vapour pressures and liquid and solid heat capacities obtained in this work supplemented by critically selected literature values.

As an extension to our previous work carried out on the measurements of vapor pressures for cycloalkanes [I. Mokbel, E. Rauzy, H. Loiseleur, C. Berro, J. Jose, Fluid Phase Equilibria, 108 (1995) 103] and polycyclic aromatic hydrocarbons [I. Mokbel, T. Guetachew, J. Jose, Eldata, Int. Electron. J. Phys. Chem. Data (1995) 167] we have performed a similar study for 12 aromatic hydrocarbons in the range 1 Pa to 200 kPa. The experimental results correlated with Wagner's equation are in a good agreement with the available literature data. Experimental vapor pressures were then represented and predicted with a group contribution method.

Several improvements of the static device developed by the authors for measuring low vapor pressures are described: 1. a installation of a supplementary pressure gauge allowing the extension of the measurement range up to 200 kPa 2. b modification of the measurement cell in order to have a good degassing of the compounds (important step in low vapor pressure measurements). The apparatus was used to measure vapor pressure (0.5 Pa to 200 kPa) of 12 alkylcyclohexanes, cyclopentane, butylcyclopentane and trans-decahydronaphthalene. The experimental results correlated using Wagner's equation are in good agreement with the available literature data. Experimental vapor pressures were then represented and predicted satisfactorily with a modified version of the Peng-Robinson equation of state in which the different parameters were expressed in terms of a group contribution method.

Several improvements of a static device for measuring low vapor pressures are described by the authors : - Installation of a second pressure gauge allowing the extension of the measurement field. - More reliable checking of the whole apparatus temperature. - Improvement of the system in order to eliminate vapors after measurements. In the new version, the apparatus allows reliable measurements in the range : −30 The uncertainty on temperature measured with a thermocouple is ± 0.02°C. The apparatus was calibrated with naphtalene and checked with water. In the latter case the discrepancy between our values and the literature data is 0.4% in the range 5–280 torr and 2% for pressures lower than 5 torr. The device was used to measure vapor pressure of 11 alkylbenzenes. The results obtained are in agreement with the few available literature data. They were correlated with the ANTOINE equation and the CARRER-ROGALSKI-PENELOUX equation.

As an extension to our previous work carried out on the measurements of vapor pressures for heavy hydrocarbons we have performed a similar study for 11 primary alcohols. Our results are in good agreement with those published by Ambrose et al. in a fairly limited temperature range and, with a few small exceptions, with those reported by Smith and Srivastava. In all cases Antoine's equation leads to small deviations from measured values. Our motivation was twofold. Firstly the existence of an IUPAC project to study vapor-liquid equilibria for mixtures of primary alcohols with n -alkanes by correlating experimental determinations and group contribution methods; it is clear that the correlations require knowledge of the vapor pressures of pure substances. Secondly, the lack of data in the low vapor pressure field.