Application of P507 and isooctanol extraction system in recovery of scandium from simulated red mud leach solution

Abstract

Abstract The current recovery technique of Sc was complicated and the chemical consumption was high. This was due to the low content of Sc in resources and the difficulty of stripping. In this research, the isooctanol was added into the 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (P507) extraction system to reduce the extraction and improve the stripping of Sc. The maximum stripping ratio of Sc from loaded organic phase by sulfuric acid can increase from 10% (without isooctanol) to 99% (with 15 vol% isooctanol). In the extraction test of the simulated red mud leaching liquor, the separation factors between Sc and Zr, Sc and Ti are 36 and 350, separately. At the same time, other metals are almost not extracted. The high selectivity and stripping of Sc suggest that the P507 with isooctanol extraction system can be applied in the practical Sc recovery process.