Ternary Solutions Research Articles

Phase equilibrium in binary La2O3-Dy2O3 and ternary CeO2-La2O3-Dy2O3 systems

Cerium oxide doped with oxides of rare earth elements is a multifunctional material, a wide range of uses which is associated with its unique physicochemical properties. Phase diagrams of multicomponent systems are the physicochemical basis for the creation of new materials with improved characteristics.In this work, phase equilibria in ternary CeO2–La2O3–Dy2O3 and binary La2O3–Dy2O3 systems in the whole concentration range were studied. No new phases have been identified in these systems. An isothermal section of the phase diagram of the CeO2–La2O3–Dy2O3 system at a temperature of 1500 °С is constructed. No new phases have been detected in the system. It was found that in the studied ternary system solid solutions are formed on the basis of (F) modification of CeO2 with structure of fluorite type, monoclinic (B), cubic (C) and hexagonal (A) modifications of Ln2O3.In the La2O3–Dy2O3 binary system (1500–1100 °С) three types of solid solutions are formed: based on hexagonal modification A-La2O3, monoclinic modification B-Dy2O3 and cubic modification C-Dy2O3 separated by two-phase fields (A+B) and (B+C), respectively. The boundaries of the regions of homogeneity of solid solutions based on A-La2O3 are determined by compositions containing 35–40, 20–25, 15–20 mol% Dy2O3 at 1500, 1250, 1100 °C, respectively. From the obtained data it follows that the solubility of Dy2O3 in the hexagonal modification of lanthanum oxide is 39 mol% at 1500 °C, 23 mol. % at 1250 °C and 16 mol% at 1100 °C. The limits of existence of solid solutions based on monoclinic B-modification are determined by compositions containing 30–35, 65–60 (1250 °С), 35–40, 55–60 (1100 °С) 40–45, 70–75 (1500 °C) mol% Dy2O3.In the studied system, with a decrease in temperature from 1500° to 1100°C, there is a decrease in the solubility of La2O3 in the crystal lattice of cubic solid solutions of C-type from 16 to 10 mol%.

In silico studies of the human IAPP in the presence of osmolytes

The human islet amyloid polypeptide or amylin is secreted along with insulin by pancreatic islets. Under the drastic environmental conditions, amylin can aggregate to form amyloid fibrils. This amyloid plaque of hIAPP in the pancreatic cells is the cause of type II diabetes. Early stages of amylin aggregates are more cytotoxic than the matured fibrils. Here, we have used the all-atom molecular dynamic simulation to see the effect of water, TMAO, urea and urea/TMAO having ratio 2:1 of different concentrations on the amylin protein. Our study suggest that the amylin protein forms β-sheets in its monomeric form and may cause the aggregation of protein through the residue 13-17 and the C-terminal region. α-Helical content of protein increases with an increase in TMAO concentration by decreasing the SASA value of protein, increase in intramolecular hydrogen bonds and on making the short-range hydrophobic interactions. Electrostatic potential surfaces show that hydrophobic groups are buried and normalised configurational entropy of backbone, and side-chain atoms is lesser in the presence of TMAO, whereas opposite behaviour is obtained in the case of urea. Counteraction effect of TMAO using Kast model towards urea is also observed in ternary solution of urea/TMAO.

Effectiveness of cranberry (Vaccinium macrocarpon, cv. Pilgrim) vacuum impregnation: The effect of sample pretreatment, pressure, and processing time

This study aimed to determine the effects of vacuum impregnation (VI) on the effectiveness of enrichment of cranberry fruit with ascorbic acid. During the research, different strategies of fruit preparation that might improve impregnation in a ternary solution containing ascorbic acid, citric acid, and sucrose were tested. The evaluation of the processes was based on an analysis of impregnation efficiency, selected quality parameters, and alterations of internal structure. The results confirm that VI proceeds efficiently with heat-treated or bisected cranberry. The pressure and length of the individual process stages also affect impregnation efficiency. The lower the pressure and/or the longer the impregnation time, the higher the ascorbic acid content in the fruit. It can be concluded that VI is an effective method for enriching difficult to process berries with valuable compounds.

Understanding butanol recovery and coupling effects in pervaporation of Acetone-Butanol-Ethanol (ABE) solutions: A modelling and experimental study

The sustainable downstream recovery of bio-butanol from multicomponent fermentation broths through organophilic pervaporation is still challenged, in part, by a limited knowledge on the effect of by-products ethanol and acetone on final butanol recovery. This study therefore involves an experimental and theoretical inquisition on extraction of butanol and coupling effects involved between the various components. A commercial polydimethylsiloxane membrane was used for pervaporation of binary and ternary model solutions. Modified solution-diffusion based models were then customized to emulate temperature and concentration dependence of permeation. Membrane performance and coupling were found to be functions of the concentration of both organic components involved as well as temperature of the feed. The membrane was observed to be most intrinsically selective towards butanol in all systems. In ternary mixtures, the presence of second organic component positively enhanced coupling effects in favor of butanol recovery but lead to a decreased membrane plasticization by butanol itself. Ultimately permeance based coupling factors revealed that membrane permselectivity towards butanol was best benefited by coupling at lower butanol to ethanol/acetone concentration ratios in feed. In contrast, minimal coupling was experienced at equimolar conditions and multicomponent pervaporation in such cases could be satisfactorily modelled as binary mixture separation.

Dissolution Behavior of Sodium Phosphate in a Na3PO4–Na2WO4–NaOH Solution System

Sodium hydroxide autoclaving is the main method for smelting scheelite in China. In this method, sodium phosphate is added as an additive to realize the highly efficient decomposition of scheelite, and a crude sodium tungstate solution containing sodium phosphate and sodium hydroxide is obtained. In the subsequent process of ion exchange, phosphorus ions in the solution compete with the resin adsorption of tungstate, which reduces the adsorption capacity of the resin and endangers the purity of the subsequent sodium tungstate solution. To remove the phosphorus from crude sodium tungstate solution, a chemical purification method is usually adopted. The principle of the chemical purification method is to use chemical reagents to react with impurities to form precipitates to achieve the purpose of impurity removal. Because of the advantages of simple industrial implementation and high impurity removal efficiency, it has been widely used in phosphorus removal from crude sodium tungstate solution. However, in the process of phosphate removal in a crude sodium phosphate solution, the chemical purification method has some disadvantages. First, the additional cost of chemical reagents is required, and other metal impurities from chemical reagents would be introduced to crude sodium tungstate solution. Second, phosphate impurity removed by the chemical precipitation method is usually sedimented in other forms but sodium phosphate, which makes the phosphate resource unable to be recycled for tungsten smelting. Therefore, a novel phosphorus removal method needs to be developed. The dissolution behavior of sodium phosphate in a Na3PO4–Na2WO4–NaOH system was investigated in this paper. The results showed that in binary or ternary solution systems of sodium phosphate, sodium tungstate, and sodium hydroxide, the common-ion effect and salt effect exist simultaneously. The common-ion effect decreases the solubility of sodium phosphate, while the salt effect increases the solubility of sodium phosphate. Increasing the concentration of sodium hydroxide or sodium tungstate and lowering the temperature of the solution can greatly reduce the phosphorus concentration in crude sodium tungstate solution, making the crude sodium tungstate solution meet industrial requirements of ion exchange. The results of the study lay a theoretical foundation for the development of new phosphorus removal methods.

Novel separation mode of HPLC based on phase-separation multiphase flow.

A novel separation mode for high-performance liquid chromatography (HPLC) is proposed based on phase-separation multiphase flow. A commercially available HPLC system was used with a packed-separation column of octadecyl-silica (ODS)-modified particles. Water/acetonitrile/ethyl acetate ternary mixed solutions, (a) 1:8:1, (b) 1:3:1, and (c) 16:3:1 (v/v/v), were delivered into the system as an eluent at 20 and 5°C. The ternary mixed solution acted as a two-phase separation solution leading to phase-separation multiphase flow. The solution flowed in the column homogeneously and heterogeneously at 20 and 5°C, respectively. 1-Naphthol (NA) and 2,6-naphthalenedisulfonic acid (NDS) were injected into the system as model analytes. At 20°C, the analyte mixture did not separate in solutions (a) and (b) while it separated in solution (c) with the elution order of NDS followed by NA. At 5°C, it did not separate in solution (a), while it separated in solution (b) with elution order of NA followed by NDS and solution (c) with elution order of NDS followed by NA more effectively than 20°C. The separation behavior and elution order are possibly caused by the phase-separation multiphase flow.

Surface properties of binary and ternary solutions studied through precision measurements

The paper deals with the surface properties of aqueous two- and three-component organic solutions (water-acetone; water-1,4-Dioxane; water-acetone-1,4-Dioxane). A modern installation, K-100 tensiometer, was used to measure equilibrium surface or interfacial tension, contact angle, etc. The du Noüy ring and the Wilhelmy plate methods were used to measure the surface tension. It shows that the surface tension isotherms for a ternary system do not contain any features uncharacteristic of the surface tension isotherms for lateral binaries. The findings made it easy to specify the adsorption of surface-active agents in water. It shows that the nature of the ternary adsorption isotherms qualitatively coincides with the binary adsorption isotherms, which leads to the conclusion that, once used together as surfactants, organic substances (acetone and 1,4-Dioxane) in water does not enhance the surface activity of each other.

Different Fuel-Adopted Combustion Syntheses of Nano-Structured NiCrFeO4: A Highly Recyclable and Versatile Catalyst for Reduction of Nitroarenes at Room Temperature and Photocatalytic Degradation of Various Organic Dyes in Unitary and Ternary Solutions.

As industrialization progresses, there is a large release of hazardous pollutants into the environment. These pollutants, which contain nitro compounds and organic dyes, are extremely dangerous due to their toxic and carcinogenic nature. An efficient, environmentally benign, and economical catalyst to degrade environmental pollutants or convert them into useful products has been of sustained interest in recent years. In this context, we report a simple and inexpensive combustion fabrication of NiCrFeO4 using different fuels such as glycine, polyvinyl alcohol (PVA), and urea, showing tremendous catalytic and photocatalytic functionalities. Rietveld refinement and X-ray diffraction studies confirmed the formation of single-phase ferrites, with crystallite sizes ranging from 3.9 to 43.31 nm. The values of optical band gap, obtained from the diffused reflectance spectroscopy technique, lie in the visible region range (1.50–1.60 eV), and hence, all the synthesized ferrites can act as good photocatalysts in the presence of visible light. All the NCF nanocatalysts were utilized for the reduction of nitroarenes and photocatalytic degradation of various cationic (RhB and MB) and anionic (MO) dyes and their mixture. NCFP displayed excellent activity for the reduction and oxidation reactions owing to its large surface area and low optical band gap. Furthermore, the photo-oxidative degradation by NCFP was also enhanced due to its low recombination of charge carriers as confirmed by the photoluminescence (PL) spectroscopy. NCFP efficiently reduces nitrobenzene to aminobenzene with 95% yield using sodium borohydride as the reducing agent in methanol medium at RT in 10 min. The results of photocatalytic activity have shown that the degradation efficiency of NCFP follows the order RhB > MB > MO in their unitary solution. Furthermore, in the case of the mixture of dyes, NCFP showed enhanced photocatalytic degradation for cationic dyes (RhB and MB) compared to that of anionic dye (MO). From the performance point of view, this catalyst can be useful in industrial application because of its high stability, greater catalytic efficiency, and cost-effectiveness.

Ce–Zr-Sm ternary oxides synthesized via a template free urea-hydrothermal method

Nano-crystalline Ce0.9Zr0.1-xSmxO2-δ (0 ≤ x ≤ 0.10) mixed oxides were synthesized for the first time by a urea-hydrothermal method without the use of template or structure directing agents. The use of a high molar ratio of urea to metal cations and temperature reaction ensures the formation of a single-phase homogeneous ternary solid solution. The (NH4)2Ce(NO3)6 precursor, in a greater proportion, together with urea acts as a structure directing agent towards the completion of a self-assembly shuttle to dumbbells to sphere sequence. The analysis of the obtained morphologies has demonstrated that the physicochemical nature of the doping precursor in solution has a strong influence on the final morphology without losing morphological control. Thus, the ZrO(NO3)2 precursor favors the formation of cauliflower-type particles whereas Sm(NO3)3 favors the formation of spheres. As a result, the morphology of the samples evolves from cauliflowers to spheres as Sm content increases in the mixed oxides, with a great effect on the high specific surface area (80–115 m2.g−1) and total pore volume (0.109–0.315 cm3.g−1) obtained in all cases. Solids reduce in three stages reaching high reduction percentages (≈50%).

Individual Dye Removal Efficiencies in a Ternary Dye Mixture by Electrocoagulation

The electrocoagulation (EC) of synthetic ternary dye mixture was investigated using sacrificial iron electrodes. Erionyl Red (ER), Isolan Bordeaux (IB), and Remazol Red (RR) textile dyes were used for preparing the ternary solution. Different operational parameters, including initial dye concentrations, salt amount, current density, EC time, and pH, were analyzed to optimize removal efficiency and energy consumption conditions. After EC treatment, the individual remaining dye concentrations were calculated by applying classical least squares (CLS). The fastest removed dye was RR and the obtained efficiency was 100% in 20 minutes at pH 6. The removal rates of IB and ER were 94% and 90% in 20 minutes and raised 98% and 95% in 60 minutes. These removal rates were obtained with 100 mg/L of each dye concentration at 293.15 K. The energy consumption was also investigated. The calculated value increased from 1.67 kWh/m3 to 5.00 kWh/m3 by raising the time from 20 minutes to 60 minutes when the current density was 2.33 mA/cm2 and the electrolyte (NaCl) amount was 3.0 g/L.

Free‐Energy Parameterization and Thermodynamics in Si–Ge–Sn Alloys

Different models are used to describe and parameterize enthalpy and free energy in GeSnSi alloys over the entire composition range from density‐functional theory calculations and are used to explore if concentrated alloys in the equiatomic concentration range are thermodynamically feasible. It is found that the energetics are very well behaved and follow the expressions of a ternary regular solution rather closely. While a small asymmetry is found in the ideal solution energetics for the three binaries, it is found that the assumption of a symmetric ideal solution as underlying the quasichemical model does not change the general findings. All free energy contributions within this work are parameterized in different approximations, providing a complete parameter set that can be used for further thermodynamic studies of the GeSnSi alloy system. In the obtained results, the enthalpy of mixing of the SiSn system has rather large values, which is maintained more or less unchanged in the ternary system, making a concentrated ternary alloy thermodynamically unfavorable. Calculating the full free energy from adding configurational and vibrational entropy contributions does not change the overall situation.

A Kinetic Monte Carlo Approach to Model Barite Dissolution: The Role of Reactive Site Geometry

Barite (Ba[SO4]) is one of the promising candidates for sequestration of radioactive waste. Barite can incorporate radium (Ra) and form ideal solid solutions, i.e., (Ba,Ra)[SO4]. Together with isostructural celestite (Sr[SO4]), ternary solid solutions, (Ba,Sr,Ra)[SO4], may exist in natural conditions. Our fundamental understanding of the dissolution kinetics of isostructural sulfates is critically important for a better risk assessment of nuclear waste repositories utilizing this mineral for sequestration. So far, the barite-water interface has been studied with experimental methods and atomistic computer simulations. The direct connection between the molecular scale details of the interface structure and experimental observations at the microscopic scale is not yet well understood. Here, we began to investigate this connection by using a kinetic Monte Carlo approach to simulate the barite dissolution process. We constructed a microkinetic model for the dissolution process and identified the reactive sites. Identification of these sites is important for an improved understanding of the dissolution, adsorption, and crystal growth mechanisms at the barite–water interface. We parameterized the molecular detachment rates by using the experimentally observed etch pit morphologies and atomic step velocities. Our parameterization attempts demonstrated that local lattice coordination is not sufficient to differentiate between the kinetically important sites and estimate their detachment rates. We suggest that the water structure and dynamics at identified sites should substantially influence the detachment rates. However, it will require more work to improve the parameterization of the model by means of Molecular Dynamics and ab initio calculations.

Thermodynamic calculation of activity interaction coefficients of Fe to P, Ti, Ni, Cu, Cr, and V in silicon-based solutions

Thermodynamic parameters of impurity components in silicon-based solution systems are of great significance to study the removal of impurities from silicon solutions. In this paper, the activity parameters of each component in Si-i (i: P, Ni, Cu, V, Ti, and Cr) binary solutions and Si-i-Fe (i: P, Ni, Cu, V, Ti, and Cr) ternary solutions, and the activity interaction coefficients of component Fe to component i (εiFe) in Si-i-Fe ternary solutions were calculated using the molecular interaction volume model (MIVM). The calculated results showed that the activity interaction coefficient of Fe to P was negative in the Si-i-Fe ternary solution, indicating that the presence of Fe was detrimental to the removal of P. Before refining to remove impurity P, reducing the content of Fe in the silicon solution can improve the removal rate of P. The activity interaction coefficients of Fe to Ti, Fe to Ni, Fe to Cu, Fe to Cr, and Fe to V were all positive, indicating that the former played a positive role in the removal of the latter. This paper provided a theoretical basis for the metallurgical removal of impurities from silicon while improving the database of thermodynamic parameters of silicon-based solutions.

Volume properties of the ternary systems (LiCl + LiB5O8 + H2O) and (Li2SO4 + LiB5O8 + H2O) from 283.15 to 363.15 K and 101.325 kPa

In this study, densities of the two ternary aqueous solution systems (LiB5O8 + LiCl + H2O) and (LiB5O8 + Li2SO4 + H2O) were measured using an accurate digital vibrating-tube densimeter from 283.15 to 363.15 K at an interval of 5 K and 101.325 kPa. B5O8- in aqueous solution was in the form of [B5O6(OH)4]-. Therefore, the complex aqueous solution of LiB5O8 is in the form of Li[B5O6(OH)4]. Subsequently, the mean apparent molar volume (VΦθ) and mixing ion-interaction parameters (θa,a′v and Ψc,a,a′v, c = Li+, a = B5O6(OH)4-, a′= Cl- or SO42-) against temperature were obtained using the Pitzer equation for the first time. And then, the temperature-dependence equations for the Pitzer mixing ion-interaction parameters and the relevant temperature correlation coefficients of the equation aj, i.e. [f (ai, T) = a1 + a2ln(T/298.15) + a3(T − 298.15) + a4/(620 − T) + a5/(T − 227)] were also obtained through the least square fitting. These volumetric properties and parameterization Pitzer parameters obtained in this work could hopefully be used for the quantitatively predictive calculation of the physicochemical properties of the mixed electrolytes containing lithium, chloride, and sulfate ions at any temperature.

Dielectric characterization and modelling of aqueous solutions involving sodium chloride and sucrose and application to the design of a bi-parameter RF-sensor

This paper reports on dielectric properties of ternary mixtures involving sodium chloride (NaCl) and sucrose (C12H22O11) dissolved into water (H2O). Broadband electromagnetic characterizations of such mixtures at various concentrations were performed, evidencing a dual behavior made of conductive effects at low frequencies and dipolar relaxation at microwave frequencies. Conductive and dielectric properties resulting from these both effects were integrated into predictive models for variations of Cole–Cole model parameters. Based upon this modelling, an innovative microwave-based sensor able to retrieve concentrations of both sodium chloride and sucrose in ternary aqueous solutions was introduced, designed, realized and assessed. The proposed sensor shows an error lower than 5.5% for concentration ranges of 0 to 154 mmol/L for sodium chloride and 0 to 877 mmol/L for sucrose.

Volumetric, ultrasonic and viscometric behavior of nucleosides (uridine and cytidine) in aqueous L-ascorbic acid solutions at different temperatures

Apparent molar properties (Vϕ, Kϕ,s), limiting apparent molar properties (Vϕo, Kϕ,so), transfer properties (ΔtrVϕo, ΔtrKϕ,so, ΔtrB), hydration number (nH) and relative viscosities (ηr) have been determined from density, speed of sound and viscosity measurements for nucleosides (uridine and cytidine) in water and in aqueous solutions of (0.1043, 0.2104 and 0.3016) mol kg−1 L-ascorbic acid at five different temperatures ranging (293.15–313.15) K by using DSA (density and speed of sound analyzer) connected with rolling ball viscometer. Viscosities of the prepared solutions have been examined to determine the Falkenhagen coefficient A, viscosity B-coefficients and its transfer parameter by using the Jones-Dole equation. The solvation behavior of nucleosides has also been computed. Based on the co-sphere overlap model, variety of intermolecular interactions predominating in the ternary solutions has been explained. By using Hepler's constant and temperature derivative of B-coefficients (dB/dT) the structure making/breaking nature of solute have been examined. Furthermore, the absorption spectra for both the nucleosides (uridine and cytidine) have been recorded in water as well as in L-ascorbic acid with the help of UV–visible spectrophotometer to investigate the interactions prevailing among these systems.

Simultaneous adsorption of three anionic dyes at neutral pH from their individual and multi-component systems on a CTAB modified Pennisetum glaucum based carbon nanotube green composite: Adsorption mechanism and process optimization by Box-Behnken design model

In this study, an efficient, cost-effective, and environmentally friendly cetyltrimethylammonium bromide (CTAB) surfactant modified Pennisetum glaucum (RM) based composite containing 0.5% functionalized carbon nanotube (CNT) has been developed. The main aim of this study was to assess and optimize the synthesized adsorbent used for the removal of Reactive Red 35 (RR), Coomassie Brilliant Blue R-250 (BB), and Eriochrome Black-T (EBT) dyes in their single, binary, and ternary solutions by employing the Box Behnken Design (BBD) under Response Surface Methodology (RSM). According to the analysis of variance (ANOVA), the proposed quadratic model was significant, with a good correlation between the experimental and predicted data of the desired response, and it can be used to navigate the design space. Furthermore, the batch adsorption experiments of anionic dyes were conducted to discuss the bio-sorption kinetics, thermodynamics, isotherms, and possible adsorption mechanisms involved in single and multi-component systems were accordingly proposed.The equilibrium experimental data was best fitted to the monolayer Langmuir adsorption isotherm model, giving a maximum adsorption capacity of 210.97, 259.07, and 289.85 mgg−1 for RR, BB, and EBT dyes, respectively, in individual component systems, at neutral pH conditions, and a pseudo-2nd-order kinetic model best followed the kinetic data. The modified Langmuir model was used to study the interactions among the dye molecules in multi-component systems, and the observed results indicate the synergistic and competitive behaviour of dyes. A regeneration study of the exhausted bio-composite evaluated the renewal efficiency. This requires simple processing methods and little expense than other adsorbents fabricated from costly materials. Ultimately, the CTAB treated Pennisetum glaucum based CNT composite could be adopted as an efficient, cost-effective, and environmentally benign green biosorbent.

Volumetric and Acoustic Studies of Interactions between L-Phenylalanine and 1-Hexyl-3-Methylimidazolium Bromide in Aqueous Solution

Experimental density (ρ) and ultrasonic velocity (c) for phenylglycine in ( 0.01, 0.03, 0.05 and 0.05) mol.kg−1 aqueous solutions of 1-hexyl-3-methylimidazolium bromide at T = (313.15 and 318.15) K. Collected values for density and ultrasonic velocity were used to compute the apparent molar volumes (V f ), the apparent molar volumes at infinite dilution (), partial molar isentropic compression (K f ,s ) and partial molar isentropic compression at infinite dilution (). Also recorded data of these mixtures were utilized to calculate pair and triplet interaction coefficients. Such thermodynamic characteristics can be used to investigate the solvation behaviour, structure formation, and many sorts of interactions in (phenylglycine + water + 1-hexyl-3-methylimidazolium bromide) ternary solutions.

1,2,4-Triazol-1-ium-p-chloro-phenacylids in hydroxyl binary solvent mixtures. Computational and solvatochromic study

Triazolium ylids and their derivatives are used as precursors for a great number of compounds in pharmaceutical and industrial fields. Triazolium ylids are amphiliophilic compounds with separated charges on positive nitrogen belonging to heterocycle and on negatively charged carbon, named carbanion and covalently bonded to the positive nitrogen. These substances are used in situ. Consequently, their interactions with the liquids, especially with water and primary alcohols are very important. The data regarding solute-solvent interactions in ternary solutions of two 4-aryl-1,2,4-trazol-1-ium-p-chloro-phenacylids were obtained by solvatochromism and by quantum chemical computations. New information about the ternary solution anisotropy and about the potential energy of molecular interactions of the type of ylid-water and ylid-ethanol are given in this study.

Binary and ternary solutions of zwitterionic compounds: theoretical and spectral studies

Theoretical bases of the solvent influence on the electronic spectra of binary and ternary solutions of some zwitterionic compounds are discussed. Three cycloimmonium ylids were investigated as spectrally active zwitterionic compounds. The energetic and electro-optical parameters of the studied molecules were obtained by using Spartan´14 programs. Some linear dependences between the wavenumbers in the maxima of the electronic spectra of the studied compounds and the solvent parameters are established. The value of the excited state dipole moment and its orientation relative to the ground state dipole moment are established based on the theories regarding the solvent influence on the electronic absorption spectra. The difference between the interaction energies in molecular pairs: ylid-solvent (1) and ylid-solvent (2) is estimated based on the statistical cell model of ternary solutions. These studies offer information about the composition of the first molecular shell surrounding the spectrally active molecules and about the nature and strength of the interactions between these molecules and their neighboring shell. Most of the ylid reactions take place in situ and from this point of view the knowledge regarding their reactivity and their interactions with solvents are very important.