Flotation concentration of a xenotime pre-concentrate.

Abstract

The worm market for rare-earths elements is increasing due to the development of new products and applications, resulting in the need for technology to treat deposits having highly complex mineralogy, such as that of Pitinga, AM, Brazil, with estimated reserves of 146,960 t of rare-earths oxides (REO), including Y203. Mineralogically the mine of Pitinga is very rich. The initial and major target of the company Paranapanema was the production of tin concentrates from placer deposits and later from primary ore. However, geological studies identified several other minerals of potential economical importance, such as: columbite-tantalite, zircon, cryolite and xenotime, the objective of the present investigation. The response of a pre-concentrate sample of the non-conducting fraction from Pitinga " s electrostatic separator to laboratory scale physical concentration methods was very poor. Another possibility for the selective separation of xenotime and zircon (the major associated mineral) is flotation. Microflotation experiments were performed in a modified HaUimond tube with pure samples of xenotime and zircon, in the presence of hydroxamate as collector and five different reagents as depressants.