A mesoporous silica support was synthesized using the sol-gel method from trichlorosilane. There is a tendency for the specific surface area and the proportion of silica particles mesopores to ...increase during all stages of sol-gel synthesis. It has been shown that the insertion of hexane and toluene, as additional solvents, into the structure-forming polyethylene glycol, makes it possible to regulate the pore size and specific surface area of silica. Silica functionalization was carried out using SILP technology. The activities of the catalytic systems based on polymer and inorganic supports immobilized by imidazole-based ionic liquids during the trichlorosilane disproportionation reaction were compared. There is a tendency for the monosilane yield for catalytic systems based on an inorganic support to increase. We identified the most promising catalyst in terms of monosilane yield and proposed a bifunctional catalyst that exhibited activity in two parallel reactions: trichlorosilane disproportionation and silicon tetrachloride hydrogenation.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Herein, we report for the first time a study dedicated to acidic gases’ solubility in ionic liquids with sterically hindered bulky anion, namely bis(2-ethylhexyl) sulfosuccinate (doc), experimentally ...evaluated at low pressures. The effect of cation change (imidazolium, pyridinium, and pyrrolidinium) on the thermophysical properties and sorption capacities was also discussed. The densities and the activation energies of the tested ILs exhibited minor differences. Furthermore, the COSMO-RS model was used to predict the free volumes of ILs aiming to investigate its influence on gas solubilities. The conducted calculations have revealed an antibate correlation between the fractional free volume (FFV) and Henry’s law constant. In particular, the lowest FFV in 1-methylimidazolium doc corresponded to the minimal sorption and vice versa. In addition, it was shown that the presence of protic cation results in a significant reduction in CO2 and H2S solubilities. In general, the solubility measurement results of the synthesized ILs have shown their superiority compared to fluorinated ILs based on the physical absorption mechanism.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
This work explored the zinc nanoparticles obtained by the one-stage induction flow levitation method. A 10 kW tube generator with an operating frequency of 440 kHz was used. The process used 8 mm ...diameter zinc granules (2 g weight) with a purity of 99.9%. Zinc wire was fed to replace the evaporated metal from the granule surface. This method productivity was 30 g/h of nanoparticles. In addition, various methods were used to characterize the resulting nanoparticles: scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-Ray fluorescence analysis (XRF), dynamic light scattering (DLS), porosimetry and inductively coupled plasma atomic emission spectroscopy (ICP-MS). The resulting nanoparticle size, determined by SEM and porosimetry, was 350 nm, while the size of the primary crystallites was 21 nm. The amount of impurities in the resulting nanoparticles did not exceed 1000 ppm.
The present research provides data on the density (ρ), viscosity (η) and ability to absorb carbon dioxide of systems containing amine, molecular solvent (MS) and choline chloride (ChCl), with the ...investigation of the physical properties of both neat amine/MS/ChCl mixtures and their samples after complete CO2 saturation. The effect of the mixture composition was studied by varying amine from primary (monoethanolamine, MEA) to secondary (diethanolamine, DEA) and tertiary (triethanolamine, TEA) amine, and the degree of its substitution from a mono- (MEA, DEA and TEA) to a doubly-substituted (ethylenediamine, EDA) compound. The role of an MS was investigated via the exchange of ethylene glycol (EG) with water and dimethylsulfoxide (DMSO). In addition, the influence of the CO2 absorption promoters present in the ternary MEA/EG/ChCl mixture at an amount of 5 wt. % was also investigated. We show that an increase in ρ and η in the amine/EG/ChCl mixture affects the properties of neat amines. This suggests that in the studied ternary mixtures, the nature of the interspecies interactions is very similar to those in the previously studied MEA/EG/ChCl system. When EG was exchanged for H2O or DMSO, a decrease in ρ and an increase in η were observed. A comparison of the data with the corresponding properties of the systems composed of each pair of the mixture components indicates that the intensity and/or number of interspecies interactions in the present ternary mixtures were stronger than those in pure H2O, DMSO and MEA. While in the presence of promoters no significant changes in the studied properties were found, for the corresponding CO2-saturated samples, the ρ and η increased proportionally to the amount of absorbed gas. This was also the case for all the systems studied in the present research. The overall CO2 absorption of the EG-based mixtures decreased when going from primary to secondary and tertiary amines; it was 21% higher for the MEA/H2O/ChCl system compared to the mixtures containing EG and DMSO, which, in turn, showed similar absorption capacities. When the promoters were added to the MEA/EG/ChCl mixture, the highest capacity was found for the piperazine-containing system.
•Four novel DESs formed by chlorides of choline family and ethylene glycol in mole ratio 1: 2 were prepared.•Densities, viscosities, refractive indices and molar volumes of DESs were measured and ...obtained in a wide temperature range.•Solubilities of NH3 were found to calculate the Henry's law constants and thermodynamics of absorption process.•NH3 absorption capacity of DESs improved by 5–57% regarding to ethaline at same conditions if changing the HBA’s structure.•1H NMR and FTIR spectroscopy investigations found out the strong coupling between ammonia and hydroxyls of DESs.
The current study deals with four novel deep eutectic solvents (DES) formed by choline-like chlorides (ChCl), namely ammonium salts with 2-hydroxyethyl and 2-(2-hydroxyethoxy)ethyl substituents, and ethylene glycol (EG) in mole ratio 1 : 2. Their thermophysical properties such as density (ρ), viscosity (η), refractive index (nD) were carefully investigated in a broad range of temperatures. The ammonia solubilities in considered DESs at T = (303.2–333.2) K and p = (100–636) kPa were measured and considering the slight deviation from ideality Krichevsky − Kasarnovsky equation were used for fitting the experimental data. Based on this, the Henry's law constants (H), partial molar volumes at infinite dilution of NH3 in DESs (VNH3∞), and then the changes of enthalpy (ΔsolH°), Gibbs free energy (ΔsolG°) and entropy (ΔsolS°) during the NH3 absorption process were obtained. For the investigated DESs an improvement of ammonia absorption capacity at 313.2 K and 101 kPa was found to be by 33 % (3.640 mol · kg−1) if changing one methyl to 2-hydroxyethyl group, by 57 % (4.295 mol · kg−1) if changing two methyl to two 2-hydroxyethyl groups, by 5 % (2.861 mol · kg−1) if changing one methyl to 2-(2-hydroxyethoxy)ethyl group, by 13 % (3.081 mol · kg−1) if changing two methyl to 2-hydroxyethyl and 2-(2-hydroxyethoxy)ethyl groups in HBA structure compared to the ethaline (ChCl : EG = 1 : 2; 2.729 mol · kg−1). This assumes occurring the gas capture via – most likely – hydrogen bonds interactions between the ammonia molecule(s) and the hydroxyalkyl fragments, while the ether’s groups in HBA structure depress the positive effect of latter and hence decrease the general ammonia solubility in the considered DESs. Indeed, the strong linking emerging between hydroxyls of HBA and NH3 leads to the deformation of solvent intrinsic structure, which was proven by 1H NMR and FTIR spectroscopy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Two novel mixtures formed by chlorides of a choline family and urea were prepared.•Their thermophysical properties were obtained in a wide temperature range.•Solubilities of NH3 and CO2 were ...estimated.•Henry's law constants were found for the studied mixtures.•Replacement of ChCl improves the gas absorption capacity of its mixtures with urea.
In the current work, two novel systems formed by chlorides of choline family (ChCl), namely ammonium salts with 2-hydroxyethyl and 2-(2-hydroxyethoxy)ethyl substituents, and urea (U) in a molar ratio 1 : 1 were obtained. Their densities (ρ), viscosities (η), refractive indices (nD) and properties related to the carbon dioxide and ammonia absorption were carefully investigated in a wide temperature range. The solubilities of NH3 and CO2 in the prepared mixtures at T = (303.2–333.2) K and p = (100–639) kPa were measured and linear correlation were used for fitting the experimental data. Based on this, the Henry's law constants both in a molality (Hm) and in a molar fraction scales (Hx), and the changes of enthalpy (ΔsolH∘), Gibbs free energy (ΔsolG∘) and entropy (ΔsolS∘) during the absorption process were calculated. The absorption capacity at 313.2 K and 101 kPa of the mixtures comprising new OH-grafted hydrogen bond acceptors (HBA) were found to be higher by 60% for NH3 and 17% for CO2 when one methyl in choline cation is exchanged by a 2-hydroxyethyl group, by 103% for NH3 and 27% for CO2 when two methyls are exchanged by two 2-hydroxyethyl groups, by 9% for NH3 and 51% for CO2 when one methyl is exchanged by a 2-(2-hydroxyethoxy)ethyl group, and by 30% for NH3 and 73% for CO2 when two methyls are exchanged by one 2-hydroxyethyl and one 2-(2-hydroxyethoxy)ethyl groups compared to the referent deep eutectic solvent (ChCl : 1.5 U). This assumes occurring the ammonia capture via most likely H-bonding interactions between the NH3 molecule(s) and the hydroxyalkyl fragments, while the ether's groups in HBA structure depress the positive effect of latter and hence decrease the general ammonia's solubility in the considered mixtures. In case of carbon dioxide, the absorption capacity of the studied mixtures correlates well with the free volume of the fluid.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Herein, we report for the first time a study dedicated to acidic gases' solubility in ionic liquids with sterically hindered bulky anion, namely bis(2-ethylhexyl) sulfosuccinate (doc), experimentally ...evaluated at low pressures. The effect of cation change (imidazolium, pyridinium, and pyrrolidinium) on the thermophysical properties and sorption capacities was also discussed. The densities and the activation energies of the tested ILs exhibited minor differences. Furthermore, the COSMO-RS model was used to predict the free volumes of ILs aiming to investigate its influence on gas solubilities. The conducted calculations have revealed an antibate correlation between the fractional free volume (FFV) and Henry's law constant. In particular, the lowest FFV in 1-methylimidazolium doc corresponded to the minimal sorption and vice versa. In addition, it was shown that the presence of protic cation results in a significant reduction in CO
and H
S solubilities. In general, the solubility measurement results of the synthesized ILs have shown their superiority compared to fluorinated ILs based on the physical absorption mechanism.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Herein, we report for the first time a study dedicated to acidic gases' solubility in ionic liquids with sterically hindered bulky anion, namely bis(2-ethylhexyl) sulfosuccinate (doc), experimentally ...evaluated at low pressures. The effect of cation change (imidazolium, pyridinium, and pyrrolidinium) on the thermophysical properties and sorption capacities was also discussed. The densities and the activation energies of the tested ILs exhibited minor differences. Furthermore, the COSMO-RS model was used to predict the free volumes of ILs aiming to investigate its influence on gas solubilities. The conducted calculations have revealed an antibate correlation between the fractional free volume (FFV) and Henry's law constant. In particular, the lowest FFV in 1-methylimidazolium doc corresponded to the minimal sorption and vice versa. In addition, it was shown that the presence of protic cation results in a significant reduction in COsub.2 and Hsub.2S solubilities. In general, the solubility measurement results of the synthesized ILs have shown their superiority compared to fluorinated ILs based on the physical absorption mechanism.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The current investigation is focused on the development of composite membranes based on polymeric ionic liquids (PILs) containing imidazolium and pyridinium polycations with various counterions, ...including hexafluorophosphate, tetrafluoroborate, and bis(trifluoromethylsulfonyl)imide. A combination of spectroscopic methods was used to identify the synthesized PILs and characterize their interaction with carbon dioxide. The density and surface free energy of polymers were performed by wettability measurements, and the results are in good agreement with the permeability and selectivity obtained within the gas transport tests. It was shown that the membranes with a selective layer based on PILs exhibit relatively high permeability with CO
and high ideal selectivity CO
/CH
and CO
/N
. Additionally, it was found that the type of an anion significantly affects the performance of the obtained membranes, with the most pronounced effect from bis-triflimide-based polymers, showing the highest permeability coefficient. These results provide valuable insights into the design and optimization of PIL-based membranes for natural and flue gas treatment.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The current investigation is focused on the development of composite membranes based on polymeric ionic liquids (PILs) containing imidazolium and pyridinium polycations with various counterions, ...including hexafluorophosphate, tetrafluoroborate, and bis(trifluoromethylsulfonyl)imide. A combination of spectroscopic methods was used to identify the synthesized PILs and characterize their interaction with carbon dioxide. The density and surface free energy of polymers were performed by wettability measurements, and the results are in good agreement with the permeability and selectivity obtained within the gas transport tests. It was shown that the membranes with a selective layer based on PILs exhibit relatively high permeability with COsub.2 and high ideal selectivity COsub.2/CHsub.4 and COsub.2/Nsub.2. Additionally, it was found that the type of an anion significantly affects the performance of the obtained membranes, with the most pronounced effect from bis-triflimide-based polymers, showing the highest permeability coefficient. These results provide valuable insights into the design and optimization of PIL-based membranes for natural and flue gas treatment.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
