Investigation of H2S Solubility in Aqueous N- Methyldiethanolamine + Amine Functionalized UiO-66 as a nano solvent

In this paper, the experimental solubility of hydrogen sulfide in aqueous N- Methyldiethanolamine + Amine Functionalized UiO-66 (UiO-66-NH2) was studied. UiO-66-NH2 was produced using solvothermal process, and its physicochemical properties were investigated by different techniques including XRD, TGA, TEM, BET, and FTIR to realize its crystalline structure, morphology, thermal stability, and porous structure. The Zeta potential of the solution was turned out to be about 26.6 mV (millivolt), meaning that UiO-66-NH2 particles are moderately stable in aqueous 40 wt.% MDEA. The solubility of hydrogen sulfide has been carried out using the isochoric saturation / or static method in two concentration grades of 0.1 and 0.5 wt.% of UiO-66-NH2 in the aqueous solution of 40 wt.% MDEA known as nanofluid. Experimental measurements were carried out at temperatures of 303.15 through 333.15 K, and pressures up 1100 kPa. Results showed that the addition of UiO-66-NH2 nanoparticles to the MDEA solution altered the results less than 3% , while the mean value of uncertainty reported in this work is about 4% , meaning that the addition of nanoparticles do not have remarkable effect on H2S solubility. In contrast, it causes an increased capacity of CO2 absorption of that solution up to 10% .

Solubilization and thermodynamic properties of simvastatin in various micellar solutions of different non-ionic surfactants: Computational modeling and solubilization capacity

The aim of this work was to solubilize simvastatin (SIM) using different micellar solutions of various non-ionic surfactants such as Tween-80 (T80), Tween-20 (T20), Myrj-52 (M52), Myrj-59 (M59), Brij-35 (B35) and Brij-58 (B58). The solubility of SIM in water (H2O) and different micellar concentrations of T80, T20, M52, M59, B35 and B58 was determined at temperatures T = 300.2 K to 320.2 K under atmospheric pressure p = 0.1 MPa using saturation shake flask method. The experimental solubility data of SIM was regressed using van’t Hoff and Apelblat models. The solubility of SIM (mole fraction) was recorded highest in M59 (1.54 x 10−2) followed by M52 (6.56 x 10−3), B58 (5.52 x 10−3), B35 (3.97 x 10−3), T80 (1.68 x 10−3), T20 (1.16 x 10−3) [the concentration of surfactants was 20 mM in H2O in all cases] and H2O (1.94 x 10−6) at T = 320.2 K. The same results were also recorded at each temperature and each micellar concentration of T80, T20, M52, M59, B35 and B58. “Apparent thermodynamic analysis” showed endothermic and entropy-driven dissolution/solubilization of SIM in H2O and various micellar solutions of T80, T20, M52, M59, B35 and B58.

Solubility Data, Solubility Parameters and Thermodynamic Behavior of an Antiviral Drug Emtricitabine in Different Pure Solvents: Molecular Understanding of Solubility and Dissolution

The solubility values, various Hansen solubility parameters (HSPs) and thermodynamic behavior of emtricitabine (ECT) in twelve different pure solvents (PS) were estimated using various experimental as well as computational methods. Experimental solubility values (xe) of ECT in twelve different PS were obtained at T = 298.2 K to 318.2 K and p = 0.1 MPa. The xe values of ECT were correlated by “van’t Hoff, Apelblat and Buchowski-Ksiazaczak λh models”. Various HSPs for ECT and twelve different PS were also calculated using “HSPiP software”. The xe values of ECT were estimated maximum in polyethylene glycol-400 (PEG-400; 1.41 × 10−1), followed by ethylene glycol, Transcutol-HP, propylene glycol, methanol, water, isopropanol, ethanol, 1-butanol, dimethyl sulfoxide, 2-butanol and EA (1.28 × 10−3) at T = 318.2 K. “Apparent thermodynamic analysis” showed an “endothermic and entropy-driven dissolution” of ECT. Overall, PEG-400 was found as the best/ideal solvent for solubility/miscibility of ECT compared to other solvents studied.

Solubilization, Hansen Solubility Parameters, Solution Thermodynamics and Solvation Behavior of Flufenamic Acid in (Carbitol + Water) Mixtures

The solubilization, solution thermodynamics, solvation behavior and Hansen solubility parameters (HSPs) of an anti-inflammatory medicine flufenamic acid (FFA) in various Carbitol + water mixtures were evaluated in this study. The experimental solubility of FFA in mole fraction (xe) was measured at T = 298.2–318.2 K and p = 0.1 MPa using a static equilibrium method. The xe values of FFA in various Carbitol + water mixtures were correlated with van’t Hoff, Apelblat, Yalkowsky–Roseman, Jouyban–Acree and Jouyban–Acree–van’t Hoff models. All the studied models showed good correlation with mean error values of less than 2%. The xe value of FFA was found to increase significantly with the increase in temperature and Carbitol mass fraction in all Carbitol + water mixtures evaluated. The maximum and minimum xe values of FFA were recorded in pure Carbitol (2.81 × 10−1) at T = 318.2 K and pure water (5.80 × 10−7) at T = 298.2 K, respectively. Moreover, the HSP of FFA was found to be more closed with that of pure Carbitol, indicating the maximum solubility of FFA in pure Carbitol. The estimated values of activity coefficients showed higher molecular interactions in FFA–Carbitol combinations compared with FFA–water combinations. Thermodynamic studies indicated an endothermic and entropy-driven dissolution of FFA in all Carbitol + water mixtures. The solvation behavior of FFA was observed as enthalpy driven in all Carbitol + water combinations evaluated.