organic molecules [ 4 – 7 ].
The aim of this study is to describe the interaction proceeding between the zwitterions of selected l -α-amino acids and dissociated potassiumchloride in aqueous solutions.
The thermodynamic parameters that
Authors:Yang Zhao, Liang Zhao, Xing Wei, Buxing Han, and Haike Yan
The enthalpies of solution of potassium chloride (KCl) in water and magnetically treated water (magnetized water) have been
measured at 298.15 K using a LKB-8700 precision solution calorimeter. From the experimental results, it was observed that
the effect of magnetic field on the enthalpy of solution is measurable. This is probably due to the distortion of the hydrogen
bond of water resulting from magnetic treatment.
Authors:S. Marinković, A. Kostić-Pulek, S. Durić, V. Logar, and M. Logar
Selenite was boiled in KCl solutions of different concentrations at the respective boiling temperatures and atmospheric pressure. The products were subjected to X-ray diffraction analysis, qualitative infrared analysis, differential thermal analysis and microscopic examination. The product obtained in 1.0 M KCl solution was the -form of calcium sulphate hemihydrate (-CaSO4·0.5H2O). In more concentrated KCl solution (1.5, 2.0, 2.5, 3.0, 3.5 or 4.0 M), the -form of calcium sulphate hemihydrate (-CaSO4·0.5H2O) was formed, and a reaction took place between KCl and CaSO4, which gave a double salt: potassium pentacalcium sulphate monohydrate (K2SO4·5CaSO4·H2O).
Authors:A. Aagli, N. Tamer, A. Atbir, L. Boukbir, and M. El Hadek
Solubility of calcium sulfate in concentrated aqueous chloride solutions is of particular significance in chloride hydrometallurgy and various crystallization processes, such as the production of potassium sulfate from phosphogypsum and potassium chloride. This paper examines an example of the second type of application in which gypsum and potassium chloride are reacted to form K2SO4. The solubility of phosphogypsum in aqueous solutions of KCl, HCl, and mixtures of both has first been measured at various temperatures and concentrations. The parameters investigated are HCl concentration up to 6M, KCl concentration up to 180 g L-1 and temperature from 25 to 80°C. In addition, the influence of co-existing chloride salts, such as (HCl+KCl), on the solubility of calcium sulfate is estimated from 25 to 80°C. The solubility increases obviously with the temperature increment as it does initially with acid concentration, reaching a maximum of about 3M HCl, 130 g L-1 KCl and then drops. At the same time, the solubility of CaSO4·2H2O decreases with increasing KCl concentration.
Authors:C. Günther, R. Pfestorf, M. Rother, J. Seidel, R. Zimmermann, G. Wolf, and V. Schröder
The enthalpy of solution of KCl in H2O (1∶2000 mol·mol−1) at 298.15 K was measured in an interlaboratory test in the G.D.R. The test material was prepared in the ASMW laboratories. The purity found on the high-precision coulometric titration of chloride was 0.9999±0.0001 g·g−1. The consensus value of the enthalpy of solution in the test was ΔHs298.15=17.47±0.07 kJ·mol−1. This result is in good agreement with experimental values from recognized international scientific laboratories. The test material is applicable as a CRM.
., Dahan, R., Pamphile, R., et al.: A single blind normal volunteer bioavailability study of a new microencapsulated potassiumchloride tablet compared with two reference potassium formulations. Eur. J. Drug Metabol. Pharmacokin., 1991, 16 (3), 241
Authors:A. Atbir, L. Aneflous, A. Marrouche, M. El Hadek, R. Cohen-Adad, and M.-Th. Cohen-Adad
Polytherm diagram of the ternary system KCl–FeCl2 –H2 O between 0 and 70C. Phase equilibria in the KCl–FeCl2 –H2 O system were studied over the temperature range 0–70C by conductimetric and analytical methods.
A solubility polytherm of the system was constructed. We have observed the crystallization fields of the KCl and FeCl2 6H2 O (at 0C), KCl and FeCl2 4H2 O (at 15, 30 and 40C) and KCl, FeCl2 4H2 O and of a double salt KClFeCl2 2H2 O are obtained at 70C.
]. Rare earth metal ions such as La 3+ , Ce 3+ , and Nb 3+ have modified the morphology and coercive field values [ 14 ]. In the present investigation, we have used potassiumchloride (KCl) as dopant and its effect on the property of TGS crystals are
Authors:Malgorzata Wszelaka-Rylik and W. Zielenkiewicz
Calorimetric and volumetric investigations of ovalbumin salting by sodium
chloride, lithium chloride, potassium chloride, lithium sulfate and ammonium
sulfate buffered solutions in the range of concentrations of about 0.2–1.2
M of salts are reported. The evolution of enthalpies and apparent molar volumes vs. salts concentration was investigated using ITC
MicroCal titration microcalorimeter and Anton Paar DMA 60/602 digital densimeter.
It was found that the changes in enthalpies of salting and apparent molar
volumes follow a similar trend. Conclusions about the ability of salts: to
precipitate ovalbumin solution are presented.