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The solubility of l -methionine in three different binary mixed solvents of water + (methanol, ethanol, acetone) were experimentally measured by gravimetric method from T = (283.15 to 313.15) K ( P = 0.1 MPa). The experimental data indicate that the solubility of l -methionine in the binary mixed solvents increases with the increasing temperature and decreases with the rise of molar concentration of organic solvents. The modified Apelblat model, the λh model and the CNIBS/R–K model were used to correlate the experimental data, and all of the models provided good fitting to the data. Furthermore, the mixing thermodynamic properties of l -methionine in different binary solvent mixtures were also calculated and discussed. The results indicate that the mixing process of l -methionine in the investigated solvents is endothermic and spontaneous. The experimental solubility and correlation equations can be used as essential data and simulation models in the purification and separation of l -methionine. [ABSTRACT FROM AUTHOR]

Potassium chloride crystals are cubic, which often leads to caking and greatly limits their applications. This caking can be overcome by modifying the crystal shape toward sphericity. Spherical particles have a high anti-caking ability and flowability. In this work, spherical KCl particles were prepared using a simple cooling crystallization process designed to function without additives. Among the four main processes in the crystallization of spherical particles, i.e., nucleation, growth, agglomeration, and attrition, agglomeration is the greatest contributor to the formation of spherical KCl particles, which were prepared following the principle that the adhesion force must be larger than the dispersion force. The adhesion free energy between KCl particles and solvents (i.e., water, n -hexane, formamide, diazomethane, methanol, ethanol, ethyl acetate, ethylene glycol, and dimethyl sulfoxide) was calculated using the Lifshitz–van der Waals acid–base approach, and water was found to be the most appropriate solvent because of its attractive interaction with the crystals. According to the relationship between the adhesion force and dispersion forces, we found that the stirring rate should be lower than 1300 rpm. Additionally, the effects of stirring rate and cooling rate on the KCl products were investigated and optimized, and the optimal conditions were found to be 400–500 rpm and 10–15 min/ ° C, respectively. All of the spherical KCl products prepared under the optimal conditions show a better morphology, flowability, and anti-caking performance than the original crystals. [ABSTRACT FROM AUTHOR]

A laser monitoring dynamic method was used to determine the solubility of 4-aminobutyric acid in five mono-solvents of methanol, formamide, 1,2-propanediol, 1,3-propanediol and water, and (methanol + water) binary solvent mixtures over the temperature ranging from 283.15 K to 323.15 K at atmospheric pressure. It turns out to be that in different mono-solvents, the solubility of 4-aminobutyric acid is temperature dependent and increases with the increasing temperature. While in (methanol + water) binary solvent mixtures, the solubility is positively correlated with temperature and negatively correlated with the mole fraction of methanol. The modified Apelblat equation, λh equation and NRTL_Binary model were employed to correlate the solubility data in five mono-solvents. While in (methanol + water) binary solvent mixtures, the NRTL_Ternary model, CNIBS/R-K model and Jouyban-Acree models were applied. It is found that the correlated results are in good agreement with the experimental results. Furthermore, with the activity coefficients considered, solution mixing thermodynamics were calculated and the dissolution process of 4-aminobutyric acid is also discussed. [ABSTRACT FROM AUTHOR]

Those comments from Acree on “Effect of β -alanine and the solvent composition on the solubility of solvate of calcium d -pantothenate containing four molecules of methanol and one molecule of water ( d -PC·4MeOH·1H 2 O)” are very valuable and helpful for improving the quality of our paper. Here according to the comments, we make a deep analysis and discussion of our article again. Firstly, we need to make a restatement that S 0 and S actually represent the solubility with no impurity in the solution and the solubility in the solution containing impurity in our article, respectively. Secondly, the experimental solubility was reanalysed by the new Cohen equation suggested by Acree Jr, and the results show that the original Cohen equation could give the better agreement. Finally, the modified Solubility-Polarity equation was adopted to correlate the solubility in terms of the relative dielectric constant. [ABSTRACT FROM AUTHOR]