Beneficiation studies of a complex REE ore

Abstract

The beneficiations of a complex rare earth element (REE) ore containing REE minerals of carbonates, silicates and oxides and other REE bearing minerals (e.g. zircon and pyrochlore etc.) by flotation and high gradient magnetic separation (HGMS) were investigated. The recoveries of the different group of minerals in the flotation concentrates and their flotation kinetics were analyzed through the mineralogical studies by MLA. By flotation nearly 90% of La and Ce and 45% of Y were recovered in the final cumulative concentrate with the mass percentage of 11.5%. The mineralogical studies indicated that over 95% of carbonates were recovered in the final cumulative concentrate in which the recoveries of three major REE minerals bastnaesite, parisite and synchysite reached over 96%. The recoveries of silicate REE minerals such as cerite(Ce) and allanite were quite high and reached 86% and 65%, respectively. The recoveries of Nb mineral pyrochlore and Zr minerals zircon and elpidite were very low. HGMS was significantly less selective in recovering La and Ce but was effective in recovering Y. The flow sheet of rougher–cleaner flotation and the flow sheet of rougher flotation–cleaner HGMS were compared. The flow sheet of rougher flotation–cleaner HGMS was showed to be more effective in recovery of Y.