A separation processing for industrial rare earth feed solution by phosphonium ionic liquid type saponification strategy

A novel ionic liquid type saponification processing based on quaternary phosphonium type bifunctional IL was developed for yttrium separation from ion-adsorbed rare earth deposit.The extractabilities of([trihexyl(tetradecyl)phosphonium][sec-octylphenoxy acetate]([P][SOPAA]) were pronouncedly higher than those of sec-octylphenoxy acetic acid(HSOPAA),a mixture of HSOPAA and[P]Cl for rare earth elements(REEs).The ion association extraction mechanism contributed to avoiding the numerous saponification procedures using alkali and resulting in saponification wastewater.After 13 stages of extraction and 6 stages of scrubbing sections,the Y(Ⅲ) was successfully separated from industrial heavy RREs feed,the purity of Y(Ⅲ) in raffinate was approximately to be 98.9%.Stripping by distilled water was effectively achieved for REEs,which contributed to the decreased consumption of acid to a considerable extent.