METHOD OF PROCESSING MOLYBDENITE CONCENTRATES Russian patent published in 2024 - IPC C22B34/34 C01G47/00 C22B1/04 C22B3/04 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy of refractory rare metals, in particular to extraction of molybdenum and rhenium from sulphide concentrates. Method of processing molybdenite concentrates involves oxidative roasting in the presence of CaO and two-stage leaching of the cinder. Annealing of the concentrate is carried out at temperature of 550±10 °C for 1-2 hours with weight ratio of CaO to molybdenite concentrate 1:1. At the first stage, the cinder is leached with water without heating at L:S = 5:1 for at least 0.5 h, and at the second stage – with a solution of a mixture of sulphuric and acetic acids at concentration of H₂SO₄ 0.75-1.0 mol/l, CH₃COOH 0.5-1.5 mol/l and their total concentration of not less than 1.5 mol/l, temperature 70±2 °C, L:S = 10:1 for 0.5 hours.

EFFECT: method provides increased complexity of use of raw materials, energy and resource saving and environmental safety during processing of molybdenite concentrates due to reduction of temperature of the roasting process for complete binding of sulphur to non-volatile compounds to 550±10 °C, elimination of reagent costs for conversion of the main component of the cinder – CaSO₄ into less soluble calcium compounds and, as a result, reduction of salt effluents, selective extraction of rhenium and molybdenum into leaching solutions is not less than 88 and 96% respectively.

1 cl, 5 ex