Purification and enrichment of low grade molybdenite concentrates

Low grade molybdenite concentrates of Uranium Corporation of India Ltd. containing 2.30% Copper, 0.24% nickel, 8.01% SiO2 and 40.87% molybdenum have been subjected to curing in hydrofluoric acid solution at ambient temperature and subsequent chloridising roasting the desilicated product at low temperature followed by aqueous leaching where over 91% SiO2, 92% Cu and 77% Ni have been removed with minor loss of Mo. The purified concentrates produced by this developed process meet the desired specification for use in conversion plant.