Showing papers in "Journal of Chemical & Engineering Data in 2010"
TL;DR: In this article, the Vogel−Fulcher−Tammann (VFT) equation was used for conductivity and viscosity data, and obtained data were analyzed with the help of the fractional Walden rule and the Walden plot.
Abstract: Temperature-dependent conductivity, viscosity, and density of four ionic liquids (ILs), 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM][BF4]), 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]), 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([EMIM][NTf2]), and 1-ethyl-3-methylimidazolium dicyanamide ([EMIM][DCA]), were measured with high precision from +80 °C down to −35 °C, if possible. Fitting parameters for the Vogel−Fulcher−Tammann (VFT) equation were obtained for conductivity and viscosity data, and obtained data were analyzed with the help of the fractional Walden rule and the Walden plot. Excellent linear behavior is observed for all ILs; however, the average slope is not unity as expected for the ideal Walden rule, but 0.92 ± 0.02. The so-called ideal KCl line that is used to compare ILs within the Walden plot is discussed, as literature data for aqueous KCl solutions show that its assumed ideality has to be modified.
409 citations
TL;DR: In this article, the melting temperature, density, viscosity, pH, conductivity, and dissolved oxygen content of the novel phosphonium-based DESs were measured as a function of temperature.
Abstract: New ionic liquids analogues, that is, deep eutectic solvents (DESs), have been successfully synthesized. These DESs have been synthesized by the reaction of phosphonium-based salts with different hydrogen bond donors. Many of these DESs have melting temperatures lower than 100 °C. Preliminary laboratory results showed that these DESs can be used in different applications, for example, electrochemical processes, separation of sugars, and so forth. Melting temperature, density, viscosity, pH, conductivity, and dissolved oxygen content of the novel phosphonium-based DESs were measured as a function of temperature. It was found that the type of the salt and hydrogen bond donor and the mole ratio of both compounds have a paramount effect on the studied properties.
339 citations
TL;DR: A review of the literature on the volatility of aprotic ionic liquids can be found in this article, with a discussion of the earliest successful study of thermal vaporization of ionic liquid and the earliest indirect measurements of their vapor pressure.
Abstract: Research on the volatility of aprotic ionic liquids is reviewed. This topic is limited to aprotic liquids since measurements have led to a generalization that this class of substances possesses extremely low vapor pressures. For research related to this topic, the period covered is 2003 to 2008. The review begins with a discussion of the earliest successful study of thermal vaporization of aprotic ionic liquids, the earliest indirect measurements of their vapor pressure, the first proof of conventional distillation of ionic liquids, and competition of vaporization with thermal decomposition seen at moderately high temperatures of (200 to 300) °C. The review then briefly discusses the nature of the vapor phase and proceeds to analyze the various approaches used to measure or predict the vapor−liquid equilibrium properties of ionic liquids, including their normal boiling point, vapor pressure, and enthalpy of vaporization. It is proposed that the most reliable thermodynamic data exist solely for the enthalp...
295 citations
TL;DR: The GCVOL group contribution method is shown to be able to predict densities for pure ethyl and methyl esters within 1 % as mentioned in this paper, and the methods of Ceriani and Meirelles (CM) and of Marreiro and Gani (MG) were applied to the viscosity data.
Abstract: To develop reliable models for the densities and viscosities of biodiesel fuel, reliable data for the pure fatty acid esters are required. Densities and viscosities were measured for seven ethyl esters and eight methyl esters, at atmospheric pressure and temperatures from (273.15 to 363.15) K. A critical assessment of the measured data against the data previously available in the literature was carried out. It is shown that the data here reported presents deviations of less than 0.15 % for densities and less than 5 % for viscosities. Correlations for the densities and viscosities with temperature are proposed. The densities and viscosities of the pure ethyl and methyl esters here reported were used to evaluate three predictive models. The GCVOL group contribution method is shown to be able to predict densities for these compounds within 1 %. The methods of Ceriani and Meirelles (CM) and of Marreiro and Gani (MG) were applied to the viscosity data. It is shown that only the first of these methods is able t...
281 citations
TL;DR: In this paper, the densities and viscosities of two imidazolium-based ionic liquids and their binaries with water, for mole fractions up to 0.6, at atmospheric pressure and temperatures from (278.15 to 363.15) K were determined.
Abstract: Despite the recent increase in the number of works addressing the effect of water on the thermophysical properties of ionic liquids (ILs), in particular densities and viscosities, the strong effect of the water content in the region of low water content on these properties requires further study for a deeper understanding of the phenomenon. Densities and viscosities of two imidazolium-based ionic liquids, 1-butyl-3-methylimidazolium dicyanamide [C4mim][N(CN)2] and 1-butyl-3-methylimidazolium tricyanomethane [C4mim][C(CN)3], and their binaries with water, for mole fractions up to 0.6, at atmospheric pressure and temperatures from (278.15 to 363.15) K were determined. The densities and viscosities of the pure ionic liquids and their binaries with water were described successfully by using several correlations. An extension to the Ye and Shreeve group contribution method shows a good agreement with the density data. An Orrick−Erbar-type approach and the Vogel−Tammann−Fulcher method were also applied to the e...
230 citations
TL;DR: In this paper, the authors reported data on the thermal conductivity of the ionic liquids 1-hexyl-3-methylimidazolium tetrafluoroborate (CAS Number, 244193-50-8), [C6mim...
Abstract: Complex systems based on nanomaterials and common solvents have been shown to have thermophysical properties that can revolutionize current utilization of heat transfer fluids and heat storage cycles. This has been made possible by the existence of thermal conductivity enhancements derived from the presence of additional mechanisms of heat transfer in comparison with the base solvent. Ionic liquids have been shown to have thermophysical properties that justify the replacement of several of the chemical processes now under exploitation, and some of the solvents used, because they can in certain conditions, be considered as green solvents. Dissolving (or mixing as a thermally stable suspension) nanoparticles in ionic liquids, forms “bucky gels”, or IoNanoFluids, which we have recently shown to have thermal conductivity enhancements ranging from (5 to 35) %. This paper reports data on the thermal conductivity of the ionic liquids 1-hexyl-3-methylimidazolium tetrafluoroborate (CAS Number, 244193-50-8), [C6mim...
209 citations
TL;DR: In this paper, the pendant drop method was implemented using a high-pressure apparatus consisting of a view cell, fitted with a high pressure capillary tube for creating pendant H2O drops in the CO2 bulk phase.
Abstract: Interfacial tension measurements are reported for the (H2O + CO2) system at pressures of (1 to 60) MPa and temperatures of (298 to 374) K. The pendant drop method was implemented using a high-pressure apparatus consisting of a view cell, fitted with a high-pressure capillary tube for creating pendant H2O drops in the CO2 bulk phase. The reported results have a relative standard deviation in most cases of less than 1.0 % and are in good agreement with literature values at low pressures. However, at higher pressures (up to 45 MPa), there is a significant scatter in the published data; the reasons for this are discussed. Measurements in the present work extend the pressure range of available data up to pressures of 60 MPa.
206 citations
TL;DR: Experimental and literature data concerning the solubility of individual light fullerenes (C60 and C70) in binary, ternary and multicomponent systems as well as the data on industrial fullerene mixture and derivatives in various organic solvents are presented and discussed as mentioned in this paper.
Abstract: Experimental and literature data concerning the solubility of individual light fullerenes (C60 and C70) in binary (individual fullerene + solvent), ternary (C60 + C70 fullerenes + solvent; C60 or C70 fullerenes + solvent 1 + solvent 2), and multicomponent (fullerenes + natural fats and oils) systems as well as the data on solubility of industrial fullerene mixtures and fullerene derivatives in various organic solvents are presented and discussed.
186 citations
TL;DR: In this paper, the solubility and diffusion coefficients of hydrogen sulfide and carbon dioxide gases in the ionic liquid (IL) 1-(2-hydroxyethyl)-3-methylimidazolium tetrafluoroborate ([hemim][BF4]), at temperatures ranging from (303.15 to 353.15) K and pressures up to 1.1 MPa, were determined.
Abstract: The solubilities and diffusion coefficients of hydrogen sulfide and carbon dioxide gases in the ionic liquid (IL) 1-(2-hydroxyethyl)-3-methylimidazolium tetrafluoroborate ([hemim][BF4]), at temperatures ranging from (303.15 to 353.15) K and pressures up to 1.1 MPa, were determined. The solubility data were correlated using the Krichevsky−Kasarnovsky equation, and Henry’s law constants at different temperatures were obtained. From the solubility data, the partial molar thermodynamic functions of solution such as Gibbs energy, enthalpy, and entropy were calculated. The diffusion coefficients were obtained for H2S and CO2 using a semi-infinite volume approach, and a correlation equation with temperature is presented for each gas. A comparison showed that the solubility of H2S was about three times its magnitude, and its diffusion coefficient is of the same order of magnitude as that of CO2 in the IL studied in this work.
184 citations
TL;DR: In this paper, an agro-waste, rice husk, was pyrolyzed in the presence of ZnCl2 and activated carbon displayed both microporous and mesoporous nature with a significant surface area of 18050 m2·g−1 Fourier transform infrared (FTIR) spectrograms of the activated carbon.
Abstract: We prepared activated carbon by pyrolyzing an agro-waste, rice husk, in the presence of ZnCl2 The activated carbon displayed both microporous and mesoporous nature with a significant surface area of 18050 m2·g−1 Fourier transform infrared (FTIR) spectrograms of the activated carbon were recorded to determine the number and positions of the functional groups available on its surface The adsorption of methylene blue (MB) from its aqueous solutions by rice husk activated carbon (RHAC) was studied The removal of dye increased from (8275 to 9320) % with decreasing initial concentration of MB from (100 to 60) mg·L−1 The time of equilibrium was found to be 100 min Higher removal was obtained at higher dose of adsorbent, and the removal increased from (8675 to 9983) % with increasing adsorbent dose from (040 to 060) g The removal of methylene blue increased from (9320 to 9916) % with increasing temperature from (30 to 50) °C at 60 mg·L−1 MB concentration, 150 rpm, and 100 μm particle size Isother
171 citations
TL;DR: In this article, an experimental study was conducted to examine the effects of salts, alkali, and surfactants on the rheological properties of partially hydrolyzed polyacrylamide (PHPAM) over a wide range of parameters.
Abstract: The rheological behavior of a polymer solution is very important for its application in enhanced oil recovery. An experimental study was conducted to examine the effects of salts, alkali, and surfactants on the rheological properties of partially hydrolyzed polyacrylamide (PHPAM) over a wide range of parameters. The experimental results show that addition of ionic species significantly reduces the polymer viscosity by reducing the hydrodynamic size of the polymer. The power-law model was used to describe the rheological properties of the solutions. The flow behavior index, n, of the samples was in the range from 0.232 to 0.275, while the consistency index, K, ranged from (1.45 to 5.76) Pa·sn. The variation of viscosity with temperature was also studied and found to satisfy the Arrhenius equation.
TL;DR: In this paper, the effect of the anion, namely dicyanamide, hexafluorophosphate, trifluoroacetate, or triffluoromethanesulfonate, on the conductivity of 1-N-butyl-3-Nethylimidazolium-based room-temperature ionic liquids (RTILs) was studied over the temperature range (248 to 468) K. The uncertainty in κ was estimated to be less than 0.5 %.
Abstract: The effect of the anion, namely dicyanamide, hexafluorophosphate, trifluoroacetate, or trifluoromethanesulfonate, on the conductivity (κ) of 1-N-butyl-3-N-methylimidazolium-based room-temperature ionic liquids (RTILs) was studied over the temperature range (248 to 468) K. The uncertainty in κ was estimated to be less than 0.5 %. The conductivity values obtained are well-described by the Vogel−Fulcher−Tammann equation. Additionally, densities (ρ) and the corresponding molar conductivities (Λ) are reported for the temperature range (278 to 338) K. The data for Λ and the associated viscosities (η) were found to fit fractional forms of the Walden relationship.
TL;DR: In this paper, the conductivity of the ionic liquids [emim][BF4], [bmim] and [hmim] from (−35 to 195) °C were reported.
Abstract: Data for the conductivity (κ) of the ionic liquids [emim][BF4], [bmim][BF4], [hmim][BF4], and [omim][BF4] from (−35 to 195) °C are reported The data can be well-fit with the Vogel−Fulcher−Tammann
TL;DR: In this article, the phase equilibrium data for the semiclathrate hydrates formed in three three-component systems, the CO2 + tetra-n-butyl ammonium bromide (TBAB) + water system, the Co2+ tetra nbutyl amine chloride (TBAC)+ water system and the CO 2 + tetric ammonium fluoride(TBAF) plus water system were measured in the pressure range of (0.40 to 3.77 MPa) and temperature range of 280.2 to 293.5
Abstract: Phase equilibrium data for the semiclathrate hydrates formed in three three-component systems, the CO2 + tetra-n-butyl ammonium bromide (TBAB) + water system, the CO2 + tetra-n-butyl ammonium chloride (TBAC) + water system, and the CO2 + tetra-n-butyl ammonium fluoride (TBAF) + water system, were measured in the pressure range of (0.40 to 3.77 MPa) and temperature range of (280.2 to 293.5 K) at (2.93·10−3 and 6.17·10−3) mole fraction of tetra-n-butyl ammonium halide. The experimental data were generated using an isochoric pressure-search method. The equilibrium data for the CO2 + TBAB + water system were compared with some experimental data from the literature. The effects of tetra-n-butyl ammonium halide concentration on the stability zone of the semiclathrate hydrates were studied. It was shown that TBAB, TBAC, and TBAF all can enlarge the hydrate stability zone, and as the tetra-n-butyl ammonium halide concentration increases, so does the hydrate stability zone. The three-phase equilibrium pressure of ...
TL;DR: In this article, the partition coefficients of 51 organic compounds in two ionic liquids (IL), 1-ethyl-3-methylimidazolium dicyanamide and trimethylhexylammonium bis((trifluoromethyl)sulfonyl)amide, were measured using inverse gas chromatography from (322.5 to 352.5) K.
Abstract: Partition coefficients of 51 organic compounds in two ionic liquids (IL), 1-ethyl-3-methylimidazolium dicyanamide and trimethylhexylammonium bis((trifluoromethyl)sulfonyl)amide, were measured using inverse gas chromatography from (322.5 to 352.5) K. These partition coefficients were converted into water-to-IL partition coefficients using the corresponding gas-to-water partition coefficients. Both sets of partition coefficients were analyzed using the Abraham solvation parameter model with cation-specific and anion-specific equation coefficients. The derived equations correlated the experimental gas-to-IL and water-to-IL partition coefficient data to within (0.12 and 0.14) log units, respectively.
TL;DR: Palm shell derived activated carbon was utilized as a potential adsorbent to remove rhodamine B (RB) from aqueous solution, and the ability of the prepared activated carbon for dye adsorption was examined in a series of batch experiments.
Abstract: Palm shell derived activated carbon was utilized as a potential adsorbent to remove rhodamine B (RB) from aqueous solution. Activated carbon was prepared from palm shell through a physiochemical activation process to yield a sample with a Brunauer−Emmett−Teller (BET) surface area of 476.8 m2·g−1. The ability of the prepared activated carbon for dye adsorption was examined in a series of batch experiments. The effect of various process parameters such as initial dye concentration [(41.8 to 208.8) μmol·L−1], solution pH (3 to 11), and temperature [(30 to 50) °C] on the adsorption capacity of the adsorbent was investigated. Various adsorption isotherms (Langmuir, Freundlich, and Temkin) were used to interpret the experimental data. The obtained sorption data were reasonably described by the Langmuir model. The Temkin isotherm confirmed the presence of a repulsive lateral interaction in the adsorbent surface. Pseudofirst- and second-order kinetic models were used to predict the kinetics of the adsorption proc...
TL;DR: In this paper, a volumetric apparatus was used for binary mixtures of carbon dioxide and water vapor on zeolites 5A and 13X with water loadings of (1.0, 3.4, and 9.4) mol·kg−1.
Abstract: Adsorption equilibria were measured for binary mixtures of carbon dioxide and water vapor on zeolites 5A and 13X using a volumetric apparatus. The experiments were conducted at (0, 25, and 50) °C with water loadings of (1.0, 3.4, and 9.4) mol·kg−1. With an increase in adsorbed water loadings, the loadings of weakly adsorbed CO2 decrease appreciably. Pure component data are described well by a multitemperature Toth isotherm. Binary data show a discrepancy with predictions of the ideal adsorbed solution theory (IAST) but are described well by a virial excess mixing coefficient (VEMC) model, which adds corrective terms to the IAST to account for nonidealities. Data measured at lower CO2 partial pressures and higher water loadings show indications of chemisorption and carbonate formation.
TL;DR: In this article, a complete set of thermodynamically consistent property data (vapor pressure, aqueous solubility, octanol-water partition coefficient and octanol−air partition coefficient) for 15 polycyclic aromatic hydrocarbons (PAHs) is derived from measured data reported in the literature.
Abstract: Accurate physical-chemical properties are of fundamental importance for interpreting and simulating the environmental fate and transport behavior of polycyclic aromatic hydrocarbons (PAHs). A complete set of thermodynamically consistent property data (vapor pressure, aqueous solubility, octanol solubility, octanol−water partition coefficient, octanol−air partition coefficient, and air−water partition coefficient) for 15 PAHs [naphthalene (Nap), acenaphthylene (Acy), acenaphthene (Ace), fluorene (Fluo), phenanthrene (Phe), anthracene (Ant), fluoranthene (Flu), pyrene (Pyr), chrysene (Chry), benzo[a]anthracene (BaA), benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF), benzo[a]pyrene (BaP), dibenzo[a,h]anthracene (DBA), indeno[1,2,3-c,d]pyrene (IP), and benzo[g,h,i]perylene (BghiP)] is derived from measured data reported in the literature. First, literature-derived values (LDVs) at 25 °C for each property and compound are obtained by averaging, regression, and extrapolation. Then the LDVs for each compou...
TL;DR: In this paper, the extraction of Zn2+, Cd2+, and Fe3+ from aqueous hydrochloride solutions using ionic liquids in the absence of chelating agents was analyzed.
Abstract: This work analyzed the extraction of Zn2+, Cd2+, and Fe3+ from aqueous hydrochloride solutions using ionic liquids in the absence of chelating agents. For this purpose, ionic liquids based on 1-(n-alkyl)-3-methylimidazolium and tetraalkylammonium cations and several anions (hexafluorophosphate, bis[(trifluoromethyl)sulfonyl]imide, tetrafluoroborate, and chloride) were tested. It was found that the ionic liquid methyltrioctylammonium chloride, [MTOA+][Cl−], allowed almost complete removal (extraction percentage > 94) of Zn2+, Cd2+, and Fe3+ from the aqueous solutions. Furthermore, efficient selective separation of Zn2+/Fe3+and Cd2+/Fe3+ was achieved using 1-methyl-3-octylimidazolium tetrafluoroborate, [omim+][BF4−], since high extraction percentages were reached for Zn2+ and Cd2+ (extraction percentage > 90) while this parameter was very low for Fe3+. These results indicate that the use of ionic liquids as an alternative to traditional extraction agents in liquid/liquid extraction of heavy metal ions is ve...
TL;DR: In this article, MgO(111) nanoplates with polar (111) surfaces were studied as adsorbents for dye pollutants removal from wastewater, and the experimental results indicated that the MgOs with polar surfaces exhibited much more favorable adsorption properties than a conventionally decomposition prepared Mg O powder (CP-MgO, SSA = 30 m2 ·g−1) and activated carbon (SSA = 1500 m2·g− 1) for Congo red solution with the initial concentration of 100 mg·L−1 in 30 min
Abstract: Nanoplates of MgO possessing the polar (111) facet as the primary surface were studied as adsorbents for dye pollutants removal from wastewater. The thickness of the MgO(111) nanoplates is (3 to 5) nm, with an average specific surface area (SSA) of 198 m2·g−1. Congo red and reactive brilliant red X3B are used as model azo dyes, and their adsorption is studied at different dye concentrations, solution pH, salt concentration, and temperatures in a batch reactor. The experimental results indicate that the MgO nanoplates with polar (111) surfaces exhibited much more favorable adsorption properties than a conventionally decomposition prepared MgO powder (CP-MgO, SSA = 30 m2·g−1) and activated carbon (SSA = 1500 m2·g−1) for Congo red solution with the initial concentration of 100 mg·L−1 in 30 min. The maximum adsorption capability of Congo red on MgO (111) nanosheets reached 131.3 mg·g−1 in 30 min, while the maximum adsorption capabilities of Congo red on CP-MgO and activated carbon were only (61.9 and 17.7) mg...
TL;DR: In this article, the self-association of three long-chain imidazolium ionic liquids (ILs), [C12mim]Br, [C14mim],Br, and [C16mim]-Br, in aqueous solution was studied by surface tension measurements over a temperature range from (278.15 to 328.15) K.
Abstract: Self-association of three long-chain imidazolium ionic liquids (ILs), [C12mim]Br, [C14mim]Br, and [C16mim]Br, in aqueous solution was studied by surface tension measurements over a temperature range from (278.15 to 328.15) K. Effects of temperature and hydrocarbon chain length of the three long-chain ILs on the critical micelle concentration (CMC) were examined. Thermodynamic parameters, ΔmicG, ΔmicH, and ΔmicS, of micellization were determined by applying a mass-action model equation. Isothermal titration microcalorimetry was used to obtain the enthalpy change upon micellization of the three long-chain ILs at 298.15 K. Moreover, the CMCs and the thermodynamic parameters (ΔmicG, ΔmicH, and ΔmicS) were determined based on the isothermal titration microcalorimetry results. These CMC values are approximately equal to the CMCs obtained by surface tension measurement.
TL;DR: In this article, the equilibrium hydrate formation conditions for the gas mixture of CO2 and H-2 with tetrabutyl ammonium bromide (TBAB) are measured.
Abstract: The equilibrium hydrate formation conditions for the gas mixture of CO2 and H-2 with tetrabutyl ammonium bromide (TBAB) are measured. The data show that TBAB can reduce the gas hydrate formation pressure as an additive with the mole fraction of (0.14, 0.21, 0.29, 0.50, 1.00, and 2.67) %. The experiments were carried out in the temperature range of (274.05 to 288.55) K and the pressure range of (0.25 to 7.26) MPa. The equilibrium hydrate formation pressure of the CO2 + H-2 + TBAB mixture is remarkably lower than that of the CO2 + H-2 mixture at the same temperature and decreases with the increase in the concentration of TBAB. In addition, to avoid the formation of pure TBAB hydrate, in which there are no CO2 or H-2, for the above gas mixture, the formation conditions of the pure TBAB hydrate with TBAB mole fraction from (0.14 to 2.67) % were also measured.
TL;DR: In this paper, the authors describe the synthesis of ionic liquids that incorporate the N-methyl-2-hydroxyethylammonium cation with various carboxylic acid anions and the study of some of their physical properties, including self-diffusion coefficients, density, speed of sound, viscosity, and refractive index.
Abstract: This report describes the synthesis of ionic liquids that incorporate the N-methyl-2-hydroxyethylammonium cation with various carboxylic acid anions and the study of some of their physical properties, including self-diffusion coefficients, density, speed of sound, viscosity, and refractive index. 1H and 13C NMR spectra were used to characterize the chemical structure of the species in concordance with FT-IR spectra. DOSY NMR spectra was used to determine the self-diffusion coefficients of the components, which were consistent with the formation of a lamellar or micellar liquid-crystal phase in samples containing an alkyl chain in the anion species. Thermoacoustic parameters showed that anion alkyl chain has an influence on the molecular packing of these ionic liquids. In addition, the effect of temperature on the properties seems to be related to the size and the type of aliphatic chain of the ionic liquid.
TL;DR: In this paper, a multi-walled carbon nanotubes (TiO2/MWCNTs) nanocomposites have been synthesized, characterized and used for the adsorption of Pb(II) from aqueous solution.
Abstract: In the present study, titanium dioxide/multiwalled carbon nanotubes (TiO2/MWCNTs) nanocomposites have been synthesized, characterized, and used for the adsorption of Pb(II) from aqueous solution. T...
TL;DR: In this paper, a series of novel ionic liquids, 2-aminoethanol tetrafluoroborate ([MEA][BF4]), 2-hydroxyethyl(methyl)amino] ethanol tetraflamboroborate (BF4), 2]-2-hydroxethyl(mino) amino) ethanol chloride (MDEA][Cl), 2-[2-methylimidazolium] ethanol phosphate (PO4), and 2]-methylmethylamino ethanol sulfate (SO4), were synthesized and characterized for carbon dioxide
Abstract: A series of novel ionic liquids, 2-aminoethanol tetrafluoroborate ([MEA][BF4]), 2-[2-hydroxyethyl(methyl)amino] ethanol tetrafluoroborate ([MDEA][BF4]), 2-[2-hydroxyethyl(methyl)amino] ethanol chloride ([MDEA][Cl]), 2-[2-hydroxyethyl(methyl)amino] ethanol phosphate ([MDEA][PO4]), and 2-[2-hydroxyethyl(methyl)amino] ethanol sulfate ([MDEA][SO4]), were synthesized and characterized for carbon dioxide capture in this work. Densities and viscosities of ionic liquids (1-butyl-3-methylimidazolium tetrafluoroborate, [MEA][BF4], [MDEA][BF4], [MDEA][Cl], [MDEA][PO4], and [MDEA][SO4]), amines + ionic liquids + H2O, ionic liquids + H2O, and amines + H2O were measured at temperatures ranging from (303.15 to 343.15) K at different mass fractions. These 16 different absorbents were prepared by mixing two or three compounds of 2-aminoethanol (MEA), 2-[2-hydroxyethyl(methyl)amino] ethanol (MDEA), 2-[bis(2-hydroxyethyl)amino] ethanol (TEA), ionic liquids, and water. The carbon dioxide capture rate and carbon dioxide captu...
TL;DR: In this article, the density and viscosity of synthesized 1-alkyl-3-methylimidazolium iodide ([Cnmim]I, n = 4, 6, 8) were measured in the wide range of temperature of (298 to 393) K.
Abstract: The density and viscosity of synthesized 1-alkyl-3-methylimidazolium iodide ([Cnmim]I, n = 4, 6, 8) were measured in the wide range of temperature of (298 to 393) K. Using a vacuum line, measurements of the viscosity were made under a water-vapor free atmosphere. The viscosity decreases sharply with temperature and increases as the alkyl chain length increases. The molecular dynamics simulation was performed for the densities of these ionic liquids to remedy the lack of literature experimental data. The results are quite in agreement with the experiments, with a maximum deviation of 3.00 % due to [C8mim]I at 358 K. The viscosities fit best in the modified Arrhenius, Vogel−Fulcher−Tammann (VFT), and Litovitz equations. The viscosities also fit in the simple linear equation we proposed recently with accuracies comparable with Litovitz and VFT.
TL;DR: Excess enthalpy measurements on four ionic liquid (1-ethyl-3methylimidazolium thiocyanate, 1-ethyl 3methyloridephosphate, ethyl(tributyl)phosphonium diethylphosphates, and 1-hexyl-3-methyleridephane trifluoromethanesulfonate) + water mixtures are reported in this paper.
Abstract: Excess enthalpy measurements on four ionic liquid (1-ethyl-3-methylimidazolium thiocyanate, 1-ethyl-3-methylimidazolium diethylphosphate, ethyl(tributyl)phosphonium diethylphosphate, and 1-hexyl-3-methylimidazolium trifluoromethanesulfonate) + water mixtures are reported. Heat capacities and densities of seven pure ionic liquids were measured. These measurements of imidazolium- and phosphonium-based ionic liquids are compared to our previous physical property measurements.
TL;DR: In this paper, the phase separation abilities of hydrophilic alcohols were compared by the effective excluded volume (EEV) of salt and the binodal curves plotted in molality, showing that the increase in the amount of phase-forming substance and the decrease in pH values are both advantageous to the formation of aqueous two-phase system.
Abstract: Binodal data for the ethanol/1-propanol/2-propanol + ammonium sulfate + water systems were determined at 29815 K On the basis of an empirical equation and lever rule, the liquid−liquid equilibrium compositions of the ethanol + ammonium sulfate + water system were directly calculated by Matlab The Othmer−Tobias equation and Bancroft equation proved the reliability of the calculation method and the corresponding tie-line data The phase-separation abilities of hydrophilic alcohols were compared by the effective excluded volume (EEV) of salt and the binodal curves plotted in molality The phase-separation abilities of the investigated alcohols are in the order of 1-propanol > 2-propanol > ethanol > methanol The mechanism of phase separation and the effects of alcohols, salts, and pH values are also discussed The results show that the increase in the amount of phase-forming substance and the decrease in pH values (from 903 to 358) are both advantageous to the formation of the aqueous two-phase system (
TL;DR: In this paper, the semi-empirical Sips equation was used to obtain parameters of interest for CO2 adsorption on a laboratory-synthesized polymeric copper(II) benzene-1,3,5-tricarboxylate (Cu-BTC) metal-organic framework.
Abstract: In this work, CO2 adsorption on a laboratory-synthesized polymeric copper(II) benzene-1,3,5-tricarboxylate (Cu-BTC) metal-organic framework was modeled by means of the semiempirical Sips equation in order to obtain parameters of engineering interest. Produced Cu-BTC samples were characterized by X-ray diffraction, thermogravimetry, and microporosimetric analysis; high crystallinity and very high specific surface area and pore volume were found. CO2 adsorption isotherms on Cu-BTC were evaluated at T ) (283, 293, 318, and 343) K for p e 1 bar by means of a volumetric technique. In order to establish a comparison, CO2 adsorption isotherms on samples of commercial 13X zeolite were determined under the same experimental conditions and then modeled in the same way as those for Cu-BTC. The modeling and experimental results indicated that relative to 13X zeolite, Cu-BTC showed higher CO2 adsorption capacities at near-ambient temperature and a lower heat release during the adsorption phase.
TL;DR: In this paper, the effect of the structure of the pyridinium-based cation, namely, its alkyl chain length and structural isomers, and the position of the second alkyls substitution on the measured properties was studied.
Abstract: Density and viscosity data for six pyridinium-based ionic liquids combined with the bis[(trifluoromethyl)sulfonyl]amide anion were measured at atmospheric pressure in the (278 to 363) K temperature range. The fundamental aim of this work is to study the effect of the structure of the pyridinium-based cation, namely, its alkyl chain length and structural isomers, and the position of the second alkyl substitution on the measured properties. Albeit many studies exist on the physical properties of ionic liquids in what concerns the nature of the anion and the length of the cation alkyl side chain, the effect of structural and positional isomerism on those properties is much less known. In addition—and since small amounts of water influence the phase equilibrium and thermophysical properties of ionic liquids—water-saturated ionic liquid samples were also studied in the (298 to 363) K temperature range. The Vogel−Tammann−Fulcher (VTF) method was applied to describe the viscosity data, and novel group contributi...