Extraction is studied by tributylphosphate (TBP) of ions of gold and silver from hydrochloric solutions during the portional and single time feed of extractant in dependence of the initial concentration of metal ions, temperature, concentration of hydrochloric acid, the ratio of organic (О) and water W phases О:W. The initial solutions contained soluble complex chlorides of gold and silver. When dissolving metal chlorides in the solution of common salt and hydrochloric acid, water soluble coordinate compound are formed that contain complex anions [AuCl 2 ] – , [AuCl 4 ] – , [AgCl 2 ] – , [AgCl 3 ] 2– , [AgCl 4 ] 3– , et al. As an extractant we used the tri-butyl ether of phosphoric acid (С 4 Н 9 О) 3 РО hat belongs to oxygen containing neutral extractants. The formation of coordinate (complex) compounds of TBP and metal polychlorides may be treated as the process of solvation of the extracted metal salt by the extractant. For selective extraction of ions of gold and silver from their hydrochloric solutions by tributylphosphate it is run feeding the extractant portionally to the solution at the minimal time of contact between the solution and the extractant; it helps extracting gold almost completely with the few first portions of the extractant at concentrations of 2n HCl 240 g/dm 3 NaCl and the temperature t = 60°С. Meanwhile the extraction of silver is kept to a minimum. Silver is extracted almost completely after the extraction of gold is over; it is done with tributylphosphate as well at concentrations of 3n HCl, 240 g/dm 3 NaCl and the temperature t = 20°С.
The high results of the silver ions extraction from the hydrochloric acid solutions of tributylphosphate during extractant portional introduction were obtained. The extractant batch inclusion increases silver extraction process and reduces the extractant expenditure. The best extraction results were obtained for the solutions with concentration 3N HCl, 240 NaCl g/dm 3 and temperature t = 20 °C. The principal technological scheme of the silver ions extraction from the hydrochloric acid solutions is presented.
High rates of iron (III) ion extraction from aqueous solutions with tributyl phosphate by sequential injection of the extractant and minimal contact time of the solution and the extractant were obtained. The sequential injection of the extractant increases iron extraction and reduces the amount of the extractant used. The best extraction results were obtained from the solutions with concentration 3N HCl, 240 g/dm 3 NaCl and temperature t = 60 С. The flow sheet of the selective iron ions extraction from the aqueous solutions is presented.
