A novel synergistic extraction system for the recovery of scandium (III) by Cyanex272 and Cyanex923 in sulfuric acid medium

Abstract

The synergistic extraction of scandium(III) with a mixture of Cyanex272 and Cyanex923 in sulfuric acid medium has been investigated in this study. At low H2SO4 concentration, the mixture of Cyanex272 and Cyanex923 exhibited an obvious synergistic extraction for Sc(III). When the concentration of H2SO4 was 0.10 mol/L and the molar fraction of Cyanex272 was 0.6, the maximal synergistic enhancement coefficient was obtained to be 5.20. What’s more, the synergistic extraction mechanism was discussed and the extracted complex was determined combined with FT-IR characterized result. Besides, the effect of temperature on the extraction of Sc(III) was investigated, and the thermodynamic parameters and equilibrium constants of extraction reaction have been calculated. In the meanwhile, the synergistic extraction system indicated of a potential practical application value for the recovery of Sc(III) from the sulfuric acid liquor of nickel laterite ores.