METHOD OF LEACHING PYRITE CONTAINING RAW MATERIALS Russian patent published in 2018 - IPC C22B3/06 C22B11/00 C22B1/02 C01G49/06 C01G1/00 C01G1/02 C01G3/00 C01G5/00 C01G7/00 C01G9/00 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy and can be used for complex processing of pyrite-containing raw materials. Non-oxidizing firing, processing of cinder with dissolution of iron, non-ferrous metals, silver and gold are carried out and their concentrates are obtained. Cinder processing is carried out in two consecutive stages. First leaching stage is carried out with a regenerated solution of copper chloride (+2) containing chlorides of alkali, alkaline earth metals or aluminum chloride, zinc chloride, ferric chloride (+3), or their mixtures, providing a chloride ion concentration in the range of 150÷250 g/l with ORP not higher than +480 mV and pH 1.6÷1.9 with extraction into solution within 90÷120 minutes of iron (+2), zinc, lead, copper, silver. Second leaching step is performed with a purified reverse copper chloride (+2) solution containing alkali, alkaline earth metal chlorides or aluminum chloride, zinc chloride, ferric chloride (+3), or their mixtures, providing a chloride ion concentration in the range of 150÷250 g/l with oxygen scavenging at ORP +620÷630 mV and pH in the range 0.5÷1.2 for 30÷60 minutes. Then, leaching is continued in the presence of a strong oxidant in amounts that ensure the maintenance of ORP of the reaction mass at the level of +680÷700 mV for 120–350 minutes.

EFFECT: complex low-waste processing of pyrite-containing raw materials is provided with a decrease in the environmental load on the environment and the receipt of liquid, conditioned commodity products.

1 cl, 9 tbl, 4 dwg