Assessment of Better Enrichment Mechanisms to Selectively Separate Rare-Earth-Bearing Minerals from Barite and Fluorite

Abstract Enrichment of rare-earth-bearing minerals is essential for the downstream extraction of rare-earth elements. This paper presents the results of preliminary flotation and other separation tests, collectively aimed at assessing better methods for separating a rare-earth-bearing mineral (bastnasite) from Ca-bearing (fluorite) and Ba-bearing (barite) minerals in a Turkish rare-earth ore. The ore was broken in an attrition scrubber and further sieved to obtain a fine size fraction (-45 μm) for further tests. The flotation tests were conducted using combinations of collectors and depressants over a wide range of pH values. The reactants are chosen based on their reported effects that can or may be related to flotation. Also, some flotation tests are evaluated with relevant literature to estimate possible flotation mechanisms. Results suggest certain combinations of flotation reagents that result in better separation of bastnasite. Bulk concentrates of barite and bastnasite may be (i) firstly collected through magnetic separation and (ii) then separated through flotation, provided that barite does not tend to float unless specific reagent combinations are adopted. Alternatively, concentrates containing fluorite and bastnasite can be further separated through magnetic separation. NaCl is detected in the separation products, which should be related to the decomposition of the siliceous minerals.