Mixture Of 2-propanol Research Articles

A laser monitoring technique for solubility study of ketoconazole in propylene glycol and 2-propanol mixtures at various temperatures

In the current study, ketoconazole solubility profile is determined in the mixtures of propylene glycol and 2-propanol at temperature range of 293.2–313.2 K by employing a laser-based monitoring setup followed by a gravimetric measurement. The generated solubility data for ketoconazole are correlated with various reported mathematical solubility models and the mean relative deviations of the back-calculated solubility data obtained from the mentioned models are calculated and used for the investigation of models' accuracies. Furthermore, the apparent thermodynamic properties of ketoconazole dissolution process are computed by using the van't Hoff and Gibbs equations. The automated monitoring of ketoconazole solubility in the mixed solvent can be a helpful method for the pharmaceutical industry and obtained solubility data extend the solubility database of ketoconazole.

Selective Volume Fraction Sensing Using Resonant- Based Microwave Sensor and its Harmonics

In this article, we propose a new technique for enabling multivariable volume fraction analysis by microwave resonator-based sensors. We address this issue using material dispersion and its nonlinear impact on the harmonic frequency shift. The concept is utilized to determine the volumetric fraction of multicomponent mixture selectively. Since the cutoff frequency of the permittivity spectrum is different in materials, by a proper selection of permittivity sampling frequencies, independent features are measured which consequently results in multivariable sensing capability. Debye model as a simplified presentation of the Cole-Cole relation plays a significant role in distinguishing the components in the mixture. For the proof of concept, mixtures of methanol, ethanol, and propanol are used as the material_under the test (MUT) and it is shown that the volume fraction of the components can be selectively distinguished. The concept in theory and experiment is verified and the formulation is explained in detail. The proposed concept paves the way toward the widespread use of microwave resonant sensors for selective real-time monitoring of chemical mixtures.

Study of the capability of 1-decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquid as solvent in the separation of water from 1-propanol or 2-propanol at different temperatures

After the good behavior of different 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquids (ILs) used as solvents in the separation of 1-propanol and 2-propanol from water, liquid-liquid equilibria data was measured from a system formed by a ternary mixture of water, 1-propanol or 2-propanol and 1-decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([dmim][Tf2N]) at 283.2, 303.2 and 323.2 K and atmospheric pressure. The non-random two-liquid (NRTL) and universal quasichemical (UNIQUAC) models were employed to obtain the thermodynamic parameters of both ternary mixtures, with good results in all cases. Finally, the capability of [dmim][Tf2N] to separate both azeotropic mixtures was studied through the distribution coefficient and selectivity and compared with the results obtained using different 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ILs.

Morphological characterization of water-based nanolime dispersions

This paper studies the morphological characteristics of calcium hydroxide nanoparticles in water based dispersions, produced following the main bottom-up (CaCl2/NaOH replacement reaction) and top-down methodologies. The work focuses on the effect of three different surfactants (TritonX-100, n-octylamine and amylamine) on the morphological characteristics of the resulting Ca(OH)2 nanoparticles and compares them with the ones produced in a mixture of water and 2-propanol. Moreover, in an attempt to approach the compatibility enhancement with siliceous stones, a calcium hydroxide—TEOS composite was also studied. The morphological, chemical and the mineralogical characterization of the nanoparticles produced were carried out by electron microscopy (SEM), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). It is shown that the modifications induced by the production methodologies limited the agglomeration phenomena and altered the morphological characteristics of nanoparticles, when compared to the results obtained by the original bottom-up method, resulting in the synthesis of hexagonal, plate-like, rounded and angular portlandite nanoparticles. The size range of the nanoparticles extended from 60 to 350 nm.

CO2 capture by quenched quaternary ammonium ionic liquid-propanol mixtures assessed by Raman spectroscopy

The hydrophobic quaternary ammonium ionic liquid (IL), N-trimethyl-N-butylammonium bis (trifluoromethanesulfonyl) imide [N4111][TFSI] with a 2-propanol additive captures significant normal CO2 (nCO2) at room temperature and ambient pressure. The 2-propanol-based mixture promotes conductivity under the nCO2 circumstance. To investigate the conformational changes induced by nCO2 important for its storage ability, Raman spectroscopy measurements on quenched quaternary ammonium IL-propanol mixtures are systematically conducted. Through liquid nitrogen quenching, the Raman intensities indicating the repulsive molecular interaction between 2-propanol and nCO2 are clearly observed, and exhibit distinct nCO2 mixing. The quenched [N4111][TFSI]-propanol mixtures highlighted that the cation-anion interaction was modified by the 2-propanol additive. Freezing sites of nCO2 correspond to amount of the nCO2 capture.

Intermolecular Interaction Studies of Brompheniramine with 1-Propanol at 303 K, 308 K and 313 K

A binary liquid mixture of brompheniramine and 1-propanol has been prepared. Various parameters such as viscosity (η), density (ρ), and ultrasonic velocity (U) are measured at 303 K, 308 K and 313 K. Using these experimental data, adiabatic compressibility (β), free length (Lf), free volume (Vf), viscous relaxation time (τ) and Gibbs free energy (ΔG) are calculated. Furthermore, excess molar volume (VmE), excess viscosity (ηE), excess sound velocity (UE), excess adiabatic compressibility (βE), excess free length (LfE), excess free volume (VfE), excess viscous relaxation time (τE) and excess Gibbs free energy (ΔGE) are also deduced. Deviations of these parameters from the ideal values are interpreted in terms of intermolecular interactions. The Redlich–Kister polynomial coefficients and standard deviations have been calculated by using those excess parameters. These observations confirm that the presence of intermolecular interactions in the liquid mixtures. Consequently, the strength of the interaction is found in the order of 303 K > 308 K > 313 K.

Ultrasound speed study of the ternary liquid mixture (water + ethanol + 1-propanol) at T = 293.15 K and P = 0.1 MPa

Sound speed measurements in 42 ternary aqueous mixtures of ethanol plus 1-propanol and new measurements in the three binary mixtures, composed by the three same components, were made at T = 293.15 K and P = 0.1 MPa. Following the volumetric study recently published, a compressibility analysis is now presented in order to complement our previous work, mainly based on derived properties such as excess partial molar isentropic compressions of the three components and their limiting values. As far as we know curves for limiting excess partial molar isentropic compressions of the i component in the ternary mixture were derived for the first time. Transfer functions of these limiting values when water and alcohol molecules are transferred from the aqueous binary to the ternary mixture, are presented and interpreted in terms of hydrophobic hydration and H-bonding effect.

Fuel Effects in Turbulent Premixed Pre-vaporised Alcohol/Air Jet Flames

To study combustion fundamentals of complex fuels under well-defined boundary conditions, a novel Temperature Controlled Jet Burner (TCJB) system is designed that can stabilise both gaseous or pre-vaporised liquid fuels. In a first experimental exploratory study, piloted turbulent jet flames of pre-vaporised methanol, ethanol, 2-propanol and 2-butanol mixtures are compared to methane/air as a reference fuel. Complementary one-dimensional laminar flame calculations are used to provide flame parameters for comparison. Blow-off and flame length as global flame characteristics are measured over a wide range of equivalence ratios. For fuel rich conditions, blow-off limits correlate well with extinction strain rate calculations. Differing flame lengths from lean to rich conditions are explained partly by different flame wrinkling that is assessed using planar laser-induced fluorescence imaging of the hydroxyl radical (OH-PLIF). A study of Lewis-number effects indicates that they have substantial influence on flame wrinkling. Lean alcohol/air flames, opposed to methane/air, have a Lewis-number greater than unity. This impedes curvature development, which promotes relatively large flame lengths. In contrast, across stoichiometric conditions, all alcohol/air mixture Lewis-numbers decrease significantly. At such conditions, alcohol/air flames show alike or even larger wrinkling compared to methane/air flames. However, quantitatively, the differences in flame length and wrinkling observed among the flames can neither be explained alone by Lewis-number differences, nor other global mixture parameters available from 1D laminar flame calculations. This study shall therefore emphasise the need for more detailed experimental analyses of the full thermochemical state of laminar and turbulent flames fuelled with complex fuels.

Solubility of codeine phosphate in carbitol + 2-propanol mixture at different temperatures

The solubility profile of codeine phosphate in the carbitol and 2-propanol mixtures at 293.2–313.2 K are determined and correlated with some developed cosolvency models. Moreover, the density values of codeine phosphate saturated solutions are also determined and fitted with the Jouyban–Acree model. The model accuracy is investigated by calculating the mean relative deviations (MRDs%). The thermodynamic parameters of codeine phosphate dissolution in the non-aqueous mixtures of carbitol and 2-propanol are also computed by using van’t Hoff and Gibbs equations.

Heterogeneous Solvent Dielectric Relaxation in Polymer Solutions of Water and Alcohols

The dynamics of polymer solutions are heterogeneous. The different molecule sizes and structures cause different mobilities of polymers and solvents. Recently, regarding the heterogeneity of water, two dielectric relaxation processes of water were argued in several supercooled polymer–water mixtures. To investigate whether this is unique to water, we performed broadband dielectric spectroscopy measurements of poly(vinylpyrrolidone)–water (PVP–water), PVP–propylene glycol, PVP–ethylene glycol, and PVP–propanol mixtures with 65 wt% PVP in a temperature range of 123–298 K. For the PVP–water mixture, α-relaxation of PVP and two distinct relaxation processes appeared simultaneously: one was the primary relaxation process of water (fast water process) and the other was the relatively small relaxation process (slow process), at a frequency between that of the α-process of PVP and the fast water process. The strength ratio of the large fast water and small slow processes remained nearly constant in all the temperatures measured. For the PVP–alcohol mixtures, in addition to the α-process of PVP, two or three relaxation processes of alcohol appeared. The primary relaxation process of alcohol above 240 K changed to the small fast secondary process. The small slow processes, which can be recognized below 240 K (the glass transition temperature of the α-process of PVP, Tg,PVP) appears at intermediate frequency between that of the PVP α-process and the primary process of alcohol. The small slow process changed to the primary larger process. The properties of the multiple relaxation processes of solvents below Tg,PVP in PVP–alcohol mixtures are completely different from those in PVP–water mixture.

Influence of transition metal based SCR catalyst on the NOx emissions of diesel engine at low exhaust gas temperatures

In this experimental study, silver nitrate (AgNO3) – tetraamin palladium (II) nitrate solution (Pd(NO3)2·4NH3) – titanium dioxide (TiO2) based catalyst was synthesized with the impregnation method for hydrocarbon-selective catalytic reduction (HC-SCR) system. In this system, 2-propanol and different mixtures of 2-propanol and adBlue were used as reducing agents and the effect of the synthesized catalyst on NOx conversion efficiency was investigated. The structural and chemical properties of the catalysts were performed by Scanning Electron Microscope (SEM), X-Ray Diffractometer (XRD) and Brunauer-Emmett-Teller (BET) instruments. Experiments were conducted using the prepared catalyst in a temperature ranging from 170 °C to 300 °C at intervals of 10 °C, and 1 space velocity (SV) of 30000 h−1 at the SCR exhaust test performance system. The tests were also performed using 2 cylinders, V-type diesel engine with constant speed of 3000 rpm and at four different engine loads (1, 2, 3 and 4 kW). In conclusion, the highest NOx conversion rate recorded in the tests was 68.1% at 4 kW engine load, 100% 2-propanol spraying condition. In addition to this, it was demonstrated that 2-propanol has positive effect on NOx conversion rate in comparison with abBlue reductant.

Flow patterns in microfluidic system of CO2 + 1-propanol, ethanol, methanol, and hexane binary mixtures at high pressures

This study focuses on the flow pattern characterization of pressurized CO2-solvent (1-propanol, ethanol, methanol, and hexane) binary mixtures in a microfluidic flow system. The flow patterns were experimentally visualized in a square cross-sectional microchannel connected to a micro swirl-mixer. The investigated flow patterns under various parameters (temperature, pressure, CO2 mole fraction, liquid solvent flow rate, and fluid Reynolds number) are compared with both vapor–liquid phase equilibriums (VLE) and CO2 phase diagrams. For all studied CO2-solvent binary systems, the tested parameters significantly affect the flow patterns, gas bubbles size formations, flow stability and fluid interfacial tension in VLE two-phase region, near VLE boundaries, and lower density region of CO2. The results of this work are useful for optimization of supercritical CO2 + co-solvent extraction processes and understanding flow patterns in microfluidic systems at high pressures.

Surface chemistry of 2-propanol and O2 mixtures on SnO2(110) studied with ambient-pressure x-ray photoelectron spectroscopy.

Tin dioxide (SnO2) has various applications due to its unique surface and electronic properties. These properties are strongly influenced by Sn oxidation states and associated defect chemistries. Recently, the oxidation of volatile organic compounds (VOCs) into less harmful molecules has been demonstrated using SnO2 catalysts. A common VOC, 2-propanol (isopropyl alcohol, IPA), has been used as a model compound to better understand SnO2 reaction kinetics. We have used ambient-pressure x-ray photoelectron spectroscopy (AP-XPS) to characterize the surface chemistry of IPA and O2 mixtures on stoichiometric, unreconstructed SnO2(110)-(1 × 1) surfaces. AP-XPS experiments were performed for IPA pressures ≤3 mbar, various IPA/O2 ratios, and several reaction temperatures. These measurements allowed us to determine the chemical states of adsorbed species on SnO2(110)-(1 × 1) under numerous experimental conditions. We found that both the IPA/O2 ratio and sample temperature strongly influence reaction chemistries. AP-XPS valence-band spectra indicate that the surface was partially reduced from Sn4+ to Sn2+ during reactions with IPA. In situ mass spectrometry and gas-phase AP-XPS results indicate that the main reaction product was acetone under these conditions. For O2 and IPA mixtures, the reaction kinetics substantially increased and the surface remained solely Sn4+. We believe that O2 replenished surface oxygen vacancies and that SnO2 bridging and in-plane oxygen are likely the active oxygen species. Moreover, addition of O2 to the reaction results in a reduction in formation of acetone and an increase in formation of CO2 and H2O. Based on these studies, we have developed a reaction model that describes the catalytic oxidation of IPA on stoichiometric SnO2(110)-(1 × 1) surfaces.

Thermophysical Properties Analysis of Poly (Ethylene Glycol) 600 + Methanol, Ethanol, 1-Propanol, and 2-Propanol Binary Liquid Mixtures

In this work, a series of thermophysical properties (apparent specific volume, excess molar volume, excess Gibbs energy of activation for viscous flow, coefficient of thermal expansion, excess coefficient of thermal expansion) of poly (ethylene glycol) 600 (PEG600) + methanol, ethanol, 1-propanol, and 2-propanol binary liquid mixtures were determined based on density and viscosity experimental measures at 293.15 K, 298.15 K, and 303.15 K and refractive indices at 298.15 K. After that, the obtained excess parameters were used to analyze the inter-intra molecular interactions in the liquid mixtures. In order to estimate the interaction parameters, the excess molar volume results were fitted to Redlich–Kister polynomial. Moreover, a set of semi-empirical relations were proposed to predict the viscosity of liquid mixtures.

Investigational explorations on operation and emission features of C.I engine supplemented by Methyl Propanol and CycloPentyl Ether mixtures

The exploration of present investigation effort is to probe the operation and emission features of Compression Ignition engine by means of oxygenated blends. The research was conducted on a single cylinder four stroke D.I Water cooled Compression Ignition engine supplied by Methyl Propanol and CycloPentyl Ether mixture in various proportions with pure Diesel. The study was accomplished by three dissimilar mixtures of Methyl Propanol (MP), Cyclo Pentyl Ether (CPE) and Diesel(D) in several ratios (MP10% + CPE5% + D85%), (MP10% + CPE10% + D80%) and (MP10% + CPE15% + D75%) in assessment with Diesel (D100%) to evaluate the influence of using Methyl Propanol-CycloPentyl Ether-Diesel blends on Compression Ignition engine performance. For the similar engine speed and compression ratio, different engine performance factors such as Brake Thermal Efficiency and Brake Specific Fuel Consumption, exhaust emissions such as Hydrocarbon, CO, and NOx, was deliberated. The outcomes designates that the fuel blends have higher BTE for all loading situations and the BTE rises with the escalation of CycloPentyl ether attentiveness. At full load, MP10% + CPE10% + D80% has reduced BSFC in contrast with Diesel. NOx emission and HC emission also reduced to great extent in fuel blends when compared to pure Diesel.

Evaluation of a modified method of extraction, purification, and characterization of lipopolysaccharide (O antigen) from Salmonella Typhimurium.

Background and Aim:Lipopolysaccharide (LPS) is an integral part of the outer cell membrane complex of Gram-negative bacteria. It plays an important role in the induction and stimulation of the immune system. Various LPS purification protocols have been developed. However, analysis of their efficacy is limited by contamination during downstream applications or the public health hazard of LPS. The aim of this study was to evaluate a modified method for extracting LPS as well as assess the purity of the extracted LPS by high-performance liquid chromatography (HPLC) analysis. Further, we evaluated its immunopotentiating function by measuring the relative RNA expression levels of splenic immune-related genes such as interleukin 1β (IL-1β) and interferon-γ (IFN-γ), after intramuscular injection of increasing concentrations of the extracted LPS in specific pathogen-free (SPF) chick.Materials and Methods:Isolation, identification, and serotyping of Salmonella Typhimurium were performed using chicken flocks. We then performed molecular typing of Salmonella isolates using conventional polymerase chain reaction (PCR). A new protocol for purification of LPS from Salmonella isolate (S. Typhimurium) was conducted. HPLC analysis of the extracted LPS in the current study was compared to existing methods. An in vivo study was performed to evaluate the ability of LPS to induce an immune response by measuring relative IFN-γ and IL-1β gene expression after injecting increasing concentrations of the extracted LPS into SPF chicks.Results:Isolation and serotyping revealed that Salmonella enterica was of the serovar Typhimurium. Confirmation was conducted by molecular typing through conventional PCR. Fractionation of the LPS extract by HPLC revealed a high degree of purity comparable with standard commercial LPS. These results demonstrate the high purity of extracted LPS based on our modified method using propanol and sodium hydroxide mixture. Intramuscular injection of the extracted LPS in 22 day-old SPF chicks, compared to the negative control, revealed significant upregulation of IFN-γ and slight downregulation of IL-1β.Conclusion:The new modified method can be used for high purity LPS extraction and demonstrates effective immunopotentiating activity.

Solubility of ketoconazole in the binary mixtures of 2-propanol and water at different temperatures

In the present study, the solubility of ketoconazole is measured by a shake – flask method in the binary solvent mixtures of 2-propanol + water at different temperatures. The experimental solubility data are correlated/back-calculated by some cosolvency models i.e. van't Hoff, Yalkowsky, Jouyban-Acree, Jouyban-Acree-van't Hoff, the mixture response surface and the modified Wilson models. Moreover, the density of ketoconazole saturated solutions is fitted by Jouyban-Acree model and the obtained equation is reported. The accuracy of these models is investigated by calculation of the corresponding MRD%. The apparent thermodynamic parameters including dissolution standard enthalpy change (ΔH∘), standard entropy change (ΔS∘), Gibbs free energy change (ΔG∘) for ketoconazole dissolution are calculated by using van't Hoff and Gibbs equations. Moreover, the preferential solvation analysis demonstrates that ketoconazole is preferentially solvated by water in water-rich and in 2-propanol-rich mixtures, but preferentially solvated by 2-propanol in mixtures of composition 0.19 < x1 < 0.58.

Green and low-cost preparation of CIGSe thin film by a nanocrystals ink based spin-coating method

An “ink” solution based process, using spin-coating technique, followed by annealing in selenium environment with different temperature programs was utilized to prepare CIGSe thin films. Herein, the CuIn0.7Ga0.3Se2 nanocrystals were synthesized using ethanol — a “green” solvent. Three different solvents: 2-propanol, 2-methoxyethanol, and their 2: 1 mixture (v/v ratio), were investigated as a dispersion medium for the as-synthesized CIGSe nanocrystals to form a stable ink solution. The last one- a mixture of 2-propanol: 2-methoxyethanol=2: 1 (v/v), was found to be the most suitable. Furthermore, the influences of various annealing modes on the CIGSe grain size and density in the resulting film were also studied. The as-prepared CIGSe thin film was around 1 µm thick and possessed a tetragonal structure. A newly developed cheaper and “greener” non-vacuum process was applied successfully from the synthesis of nanocrystals to the formation of ink solution, and produced high quality thin films; this opens a new route to the cost-competitive commercialization of CIGSe thin film solar cells.

Effect of solvent on thermal transitions and conductivity of poly (vinylidene fluoride) gel electrolytes

ABSTRACTThe melting (Tm) and crystallization (Tc) temperature increased with increasing solvent phenyl propanol (PhP) concentration in the mixture of solvent propylene carbonate and phenyl propanol (PC/PhP). It is also a little enhances of Tm and Tc with adding ethylene carbonate (EC) to propylene carbonate (PC). The melting (Tm) and softening temperature (Tsoft) follows the following order of solvents PC<EC:PC<PhP:PC. There was a small change of modulus was observed with the addition of PhP. The conductivity falls with increasing PhP concentration and viscosity and re-calculate free ion concentration. The adding EC to PC raises temperatures slightly, but conductivity much the same. The overall, adding poorer solvent PhP increases the melting and crystallization temperatures at the expense of conductivity, but a little changes was observed in storage modulus, much better gel network, thereby securing the continuity of the complex leads to more flexible ductile and crystalline phase serves better mechanical properties. The crystallinity of PVDF gel electrolyte is about 50%, which facilitate to changes gel network structure slightly with PhP concentration. The formation of fully interconnected three dimensional frame work structure uniformly distributed pores with large surface area can function as efficient channels for ion conduction.

Investigation of the Microstructure and Rheology of Iridium Oxide Catalyst Inks for Low-Temperature Polymer Electrolyte Membrane Water Electrolyzers.

We present an investigation of the structure and rheological behavior of catalyst inks for low-temperature polymer electrolyte membrane water electrolyzers. The ink consists of iridium oxide (IrO2) catalyst particles and a Nafion ionomer dispersed in a mixture of 1-propanol and water. The effects of ionomer concentration and catalyst concentration on the microstructure of the catalyst ink were studied. Studies on dilute inks (0.1 wt % IrO2) using zeta potential and dynamic light scattering measurements indicated a strong adsorption of the ionomer onto the catalyst particles which resulted in an increase in the ζ-potential and the z-average diameter. Steady-shear and dynamic-oscillatory-shear rheological measurements of concentrated IrO2 dispersions (35 wt % IrO2) indicated that the particles are strongly agglomerated in the absence of the ionomer. The addition of even a small amount of the ionomer (2.4 wt % with respect to total solids) caused the rheology to transition from shear thinning to Newtonian because of the reduction in agglomerated structure due to stabilization of the aggregates by the ionomer, consistent with the behavior of dilute inks. At intermediate ionomer loadings, between 2.4 and 9 wt %, the viscosity increased with increasing ionomer wt %, though remained Newtonian, predominantly due to the increasing ionomer volume fraction in the ink. For ionomer loadings greater than 9 wt %, the particles were found to be flocculated, likely induced by a dispersed ionomer. The flocculated inks exhibited strong shear-thinning and gel-like behaviors in steady-shear and oscillatory-shear rheology. The onset of flocculation was found to be sensitive to the catalyst concentration, where below 35 wt % of IrO2, flocculation was not observed. The rheological observations were further verified by ultra-small-angle X-ray scattering.