Separation of rubidium from potassium in rubidium ore liquor by solvent extraction with t-BAMBP

The ability of 4-tert-butyl-2-(α-methylbenzyl) phenol (t-BAMBP) to separate rubidium from potassium in an alkaline solution obtained from the treatment of rubidium ore has been assessed. The effects of various factors on extraction, scrubbing, and stripping were investigated under batch test conditions. A fractional extraction simulation test (3 stages for extraction and 10 stages for scrubbing) was conducted under the optimal extraction and scrubbing conditions of 1 mol/L t-BAMBP (in xylene), a contact time of 1.5 min, and a volumetric phase ratio (organic:aqueous; O/A) for extraction/scrubbing of 3:1. A Rb extraction efficiency of 98% and a K stripping efficiency of 99.5% were achieved. After 2 stages of countercurrent stripping with 1 mol/L HCl at a phase ratio (O/A) of 4:1 for 1.5 min, the stripping efficiency of Rb reached 99%. After the extraction, scrubbing, and stripping operations, a 97% total recovery of Rb was achieved and the concentration ratio of rubidium to potassium (Rb/K) increased 500 times, from 0.03 in the feed solution to 15 in the stripping solution. The experimental results show that the efficient separation of Rb from K in rubidium ore liquor with high alkalinity can be achieved via fractional extraction.