TWO-STAGE COUNTERCURRENT LEACHING PROCESS FOR THE RECOVERY OF PHOSPHATES, YTTRIUM AND RARE EARTH VALUES

摘要

Phosphates and yttrium and rare earth metal values are recovered from solid materials, particularly phosphate ores or commercial concentrates and especially apatites, in a two-stage leaching process comprising a first extraction with an aqueous acid solution to remove part of the phosphate and a substantial part of the yttrium and a second extraction with stronger acid to remove the residual phosphate, yttrium and rare earth values, then recovering the products from the first and second extracts. The process is carried out in a countercurrent manner by using the aqueous acid solution from the second extraction, after partial removal of yttrium and rare earth values, in the first extraction.