The salting-out of molibdoferrats(II) from aqueous solutions by the organic solvents
Keywords:molybdoferrates(II), асetone, solubility, dielectric constant
AbstractThe aim of this work was to develop a method for producing of molybdoferrate(II) precipitates by salting-out them from aqueous solutions by means of organic solvents. Dependence of the composition of molybdoferrate(II) precipitates on the pH of the reaction solutions was studied. Experiments on salting-out of molybdoferrate(II) with various organic solvents were carried out. As a result it was found that the best reagent for the molybdoferrate(II) salting-out is acetone. By its use, lowest quantity of the ammonium sulfate impurities was obtained. It is also of importance that by using of acetone the process of regeneration by distillation of the reaction solutions is characterized by the lowest energy consumption. A functional relationship between the solubility of molybdoferrates(II) and dielectric constant of the medium was established. By increasing the dielectric constant of the solvent solubility of molybdoferrates(II) rapidly increases. The linearized dependence ln(lnS)–ln(1/e) was proposed to predict the solubility of molybdoferrates(II) in various aqueous-organic solutions.
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