VFT, Inc has developed a cost-effective fiber reactor extraction process to remove iron impurity from feedstocks. A chloride based Pregnant Leach Solution with a total rare earth content of 89.2 g/L and a total iron impurity 560 mg/L was stripped of 99.8% iron contaminant after a single stage using solvent extraction (Figure 3).
Losses of light rare earths (La:Gd) to co-extraction were on average 4.2%, no losses were observed for the heavy rare earth (Tb through Lu, + Y). Fiber Reactor Technology was also capable of stripping lights (La:Nd) from heavies (Sm:Lu) in one stage to 99.8% purity and >77% yield.