The equilibrium solubility of benzoic acid in water and ethanol, as well nine {ethanol (1) + (2)} mixtures, was determined from T = (293.15 to 323.15) K. Benzoic mole fraction these aqueous-ethanolic mixtures adequately correlated with some well-known correlation/prediction models, obtaining mean percentage deviations 2.2 7.6%. Apparent thermodynamic quantities, namely, Gibbs energy, enthalpy, ...

Solubility of pharmaceutical drugs in organic solvents is one the important parameters to understand equilibrium concentration solute-solvent, which helps optimize and design crystallization conditions obtain desired product crystals. In present study, Chlorzoxazone (CHZ) used as a model compound investigate solubility, influence solvent operating on shape, size distribution. The solubility CHZ...

The solubilities of the assemblages albite + paragonite + quartz and jadeite + paragonite + quartz in H2O were determined at 500 and 600 !C, 1.0–2.25 GPa, using hydrothermal piston-cylinder methods. The three minerals are isobarically and isothermally invariant in the presence of H2O, so fluid composition is uniquely determined at each pressure and temperature. A phase-bracketing approach was u...

Varnish and sludge formation are considered as one of the most common problems in lubrication and hydraulic systems. In order to simulate the condition of sludge formation, base stock lubricant (Group 1 API) has been selected and exposed to heat in a laboratory setup. Sludge formation process accelerated in the laboratory scale and solid liquid equilibrium data were extracted. Then solid-liquid...

The solid-liquid solubility of the thermodynamically stable form I of the drug risperidone has been determined by a gravimetric method in nine pure organic solvents in the temperature range 278.15–323.15 K. The melting temperature and associated enthalpy of fusion of risperidone form I has been determined by differential scanning calorimetry (DSC) to be 442.38 K and 43.94 kJ mol, respectively. ...

A case study of cerussite-dominated mine tailings (5-7 wt% Pb) from the former lead-zinc Grogwynion Mine, Mid Wales (UK), is presented with the objective of providing an improved understanding of the chemical speciation that controls element release from the waste in the short and long term. An experimental and modelling approach was used to examine the effects of pH changes in fresh waters int...

Experimental studies generally performed at this laboratory on the solubility of particular salts and oxides in dilute and concentrated aqueous solutions of electrolytes at temperatures up to 400°C are presented. The techniques used are described. Some of this work applies an extended Debye-HUckel equation as a function of the ionic strength of the solution at the high temperatures. From the va...

The main objective of this work was to study and to characterize cocoa butter and the binary system cocoa butter/supercritical carbon dioxide (SC-CO2). In this way, it was measured the density and the solubility of the heavy phase in equilibrium at high pressures at 40 and 50oC, as the density and compressibility of cocoa butter. The density measurements were done trough an autoclave with a sap...

A high dosage of albendazole (ABZ) is required for treating systemic helminthe infections because of its low solubility. Aiming at increasing ABZ solubility, complexation with beta-cyclodextrin ( -CD) using aqueous and acetic acid solutions as ABZ solubilizer was studied. In aqueous -CD, complexation increased solubility 53.4 times, giving a complex equilibrium constant of 1266 L mol with a max...