SORPTION EXTRACTION OF PLATINUM METALS FROM CHLORIDE – SULFATE AND SULFATE ACIDIC SOLUTIONS BY POLYACRYLONITRILE FIBERS FIBAN

Abstract

The sorption of platinum group metals by fibers FIBAN AK-22 and A-5 from acidic chloride-sulfate and sulfate solutions was studied under static conditions. FIBAN contains primary, secondary and tertiary amino groups. The degree of extraction of platinum metals is calculated. The optimal conditions of sorption from the model solutions are determined. The influence of the temperature regime on the sorption process is established. It is shown, that all platinum group metals are quantitatively extracted from acidic chloride-sulfate solutions by fiber FIBAN AK-22 regardless of the concentration of chloride ions, H2SO4 and temperature absorption. Extraction exceeds 96% at a concentration of sulfuric acid up to 3 mol/dm3 and chloride ion up to 1 mol/dm3. Extraction of osmium is maximum at a concentration of sulfuric acid and chloride ion 3 mol/dm3. The degree of extraction of platinum group metals on FIBAN A-5 is from 50 to 85% and is maximum at elevated temperature and concentrations of H2SO4 and chloride ion 1 mol/dm3 and decreases with increasing concentration of sulfuric acid. Electronic spectra of platinum metal solutions were obtained and the state of platinum metals in chloride and chloride-sulfate solutions was estimated. After the introduction of sulfuric acid into the system, changes in the electronic spectra of platinum (IV), ruthenium and osmium solutions were noted. The spectra of palladium, rhodium and iridium solutions have not changed. When extracting platinum metals from production sulfate solutions of complex composition with a high content of macro components (Ni, Cu, Fe, Te and Se), the efficiency of fiber AK-22 is shown. The advantages of fiber FIBAN AK-22 over FIBAN A-5 are noted.