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The effects of various concentrations of sodium tosylate (NaT) hydrotrope on aggregation phenomena of antidepressant drug imipramine hydrochloride (IH) were investigated at four different temperatu...

The effect of various hydrotropes such as sodium salicylate, sodium benzoate, and nicotinamide on the solubility and mass transfer coefficient of stearic acid was investigated under a wide range of hydrotrope concentrations, (0 to 3.0) mol·kg−1, and different system temperatures, T = (303 to 333) K. It was found that the solubility and mass transfer coefficient of stearic acid increase with the increase in hydrotrope concentration and also with system temperature. All hydrotropes used in this work showed an enhancement in the solubility and mass transfer coefficient to different degrees. The order of increase in the solubility and mass transfer coefficient of stearic acid with respect to different hydrotropes was found to be sodium salicylate > sodium benzoate > nicotinamide. The maximum enhancement factor value has been determined for both the solubility and the mass transfer coefficient. The effectiveness of hydrotropes was measured in terms of Setschnew constant Ks and reported for all hydrotropes used...

A comprehensive study on the effect of hydrotropes such as urea, citric acid, sodium salicylate, and nicotinamide on the separation of phenol from phenol/o-chlorophenol mixtures under a wide range of hydrotrope concentrations, (0 to 3.0) mol·L−1, and different system temperatures, (303 to 333) K, has been undertaken. The performance of hydrotropes toward separation of phenol was measured in terms of the Setschenow constant KS. A Minimum Hydrotrope Concentration (MHC) in the aqueous phase was found essential to initiate significant separation of phenol from the phenol/o-chlorophenol mixture. The maximum enhancement factor which is the ratio of the percentage extraction value in the presence and absence of a hydrotrope has been determined for each case.

This work presents a comprehensive study on the effect of hydrotropes on the solubility and mass transfer coefficient of benzyl benzoate in water. The solubility studies were performed using hydrotropes such as tri-sodium citrate, urea, sodium benzoate, and sodium salicylate for various concentrations in the range from (0 to 3.0) mol·L-1 and system temperatures ranging from T = (303 to 333) K. The performance of the hydrotropes was measured in terms of the Setschenow constant (KS). It was found that the solubility of benzyl benzoate increases with an increase in hydrotrope concentration and also with system temperature. A minimum hydrotrope concentration (MHC) in the aqueous phase was required to initiate significant solubilization of benzyl benzoate. Consequent to the increase in solubilization of benzyl benzoate, the mass transfer coefficient was also found to increase with an increase in hydrotrope concentration. All hydrotropes used in this work showed an enhancement in the solubility and mass transfe...

A comprehensive investigation of the solubility and mass transfer coefficient enhancement of benzyl acetate through hydrotropy has been undertaken. The solubility studies have been carried out with hydrotropes such as citric acid, urea, sodium benzoate, and sodium salicylate for a wide concentration range from 0 to 3.0 mol/L-1 along with system temperature from T = 303 to 333 K. The effectiveness of hydrotropes was measured by the determination of Setschenow constant “Ks”. The solubility of benzyl acetate increases with increasing hydrotrope concentration and also with system temperature. A minimum hydrotrope concentration (MHC) in the aqueous phase was required to initiate significant solubilization of benzyl acetate. Consequent to the increase in solubilization of benzyl acetate, the mass transfer coefficient was also found to increase with increasing hydrotrope concentration. A threshold value of MHC is to be maintained to have an appreciable enhancement in the mass transfer coefficient. The maximum en...

Hydrotropes enhance solubility of water-insoluble or sparingly soluble solutes such as o- and p-hydroxyacetophenones (HAPs) in aqueous solutions. The solubility of HAPs is experimentally determined in aqueous solutions of sodium cumene sulfonate (NaCS), sodium p-xylene sulfonate (NaXS), and sodium p-toluene sulfonate (NaPTS). The solubility of phenols increases almost by an order of magnitude at higher concentrations of the hydrotropes in the order NaPTS, NaXS, and NaCS, at a given temperature. The solubility o-HAP was twice that of p-HAP in the NaCS solutions, and a similar trend was observed in other hydrotrope solutions. The solubility data was fitted in the Association model of hydrotropy to estimate the hydrotrope−hydrotrope and hydrotrope−solute interaction parameters. NaCS, the more hydrophobic hydrotrope, shows stronger interaction with the phenols and a higher association constant.

This paper presents a comprehensive study on the effect of citric acid, sodium benzoate, sodium salicylate, and urea (hydrotropes) on the solubility and mass transfer coefficient for the extraction of methyl salicylate in water. A Minimum Hydrotropic Concentration (MHC) in the range between 0.20 and 0.90 mol/L was found essential to show a significant increase in the solubility and mass transfer coefficient for the methyl salicylate−water system. The solubility of methyl salicylate has been increased to a maximum value of 22.84 in the presence of citric acid as hydrotrope at concentration of 2.00 mol/L and temperature of 333 K. The maximum enhancement factor for the mass transfer coefficient was found to be 7.88 in the presence of citric acid as hydrotrope at a concentration of 2.00 mol/L at 303 K at 600 rpm. The Setschenow constant, Ks, a measure of the effectiveness of the hydrotrope, has been determined for each case, and the highest value has been observed as 0.743 in the case of citric acid.

This paper presents a comprehensive study on the effect of citric acid, sodium benzoate, sodium salicylate, and urea (hydrotropes) on the solubility and mass-transfer coefficient for the extraction of butyl acetate in water. The influence of a wide range of hydrotrope concentrations (0-3.0 mol/L) and different temperatures (303 K to 333 K) on the solubility of butyl acetate has been studied. The influence of different hydrotrope concentrations on the mass-transfer coefficient for the butyl acetate +water system has been ascertained. The Setschenow constant, K s , a measure of the effectiveness of hydrotrope, has been determined for each case. The solubility of butyl acetate increases with increase in hydrotrope concentration and also with temperature. Consequent to the increase in the solubility of butyl acetate, the mass-transfer coefficient was also found to increase with increase in hydrotrope concentration. A minimum hydrotrope concentration was found essential to show a significant increase in the solubility and mass-transfer coefficient for the butyl acetate + water system. The enhancement factor, which is the ratio of the value in the presence and absence of a hydrotrope, is reported for both solubility and mass-transfer coefficient.

The separation of chlorobenzoic acids from their mixtures of o- and p-components in hydrotrope solutions was investigated. The aqueous solubilities of o- and p-chlorobenzoic acids in different conc...

The hydrotrope sodium butyl monoglycol sulfate for the separation of mixtures of o-, m-, and p-chloronitrobenzenes was explored at the eutectic compositions. Three ternary diagrams were constructed using the single- and two-component equilibrium compositions of binary mixtures at different hydrotrope concentrations together with eutectic and two-component saturation tie lines. It was possible to separate two of the three binary simple and the ternary eutectics because sodium butyl monoglycol sulfate was able to shift their equilibrium curves away from the eutectic tie lines.

The solubilities of 6-aminopenicillanic acid and phenoxyacetic acid were determined at 25 °C in aqueous solutions of several hydrotropes by the weight disappearance method at different hydrotrope concentrations. Commercially available aqueous hydrotrope solutions employed were 50 mass % sodium butyl monoglycol sulfate, 40 mass % sodium cumenesulfonate, 40 mass % sodium xylenesulfonate, and 40 mass % potassium−sodium xylenesulfonate, all the hydrotrope concentration mass percentages being expressed on a mass/mass basis. At high concentrations, above the threshold hydrotrope concentration, hydrotropes enhance the solubilities of these components differently. The ternary solid−liquid phase equilibrium diagram for the 6-aminopenicillanic acid−phenoxyacetic acid−water system with sodium butyl monoglycol sulfate as a hydrotrope was constructed. Solubilities of 6-aminopenicillanic acid were also determined in the reaction product mixture with or without the 30 mass % sodium butyl monoglycol sulfate hydrotropic m...

The solubilities of m- and p-aminoacetophenones were determined in aqueous solutions of several hydrotropes by the weight disappearance method at different hydrotrope concentrations and temperatures. Commercially available aqueous hydrotrope solutions employed were 50% sodium butyl monoglycol sulfate, 40% sodium cumenesulfonate, 40% sodium xylenesulfonate, 40% sodium toluenesulfonate, and 40% ammonium xylenesulfonate, all the hydrotrope concentrations being expressed in mass/mass. At high concentrations, above the threshold hydrotrope concentration, hydrotropes enhance the solubilities of these components differently. The differences in solubilities with hydrotrope concentration and temperature can be exploited for the separation of these isomers

Hydrotropes at high concentrations can substantially enhance the solubilities of o- and p-chlorobenzoic acids in aqueous solutions. The solubilities of o- and p-chlorobenzoic acids are determined in aqueous solutions of sodium butyl monoglycol sulfate (NaBMGS) and sodium p-toluenesulfonate (Na-p-TS) at temperatures of 303, 313, and 323 K. o-Chlorobenzoic acid is solubilized to a larger extent than p-chlorobenzoic acid. Setschenow constants for both the acids are reported at 303, 313, and 323 K. The data are also fitted in a quadratic function of the concentration of a hydrotrope