Loading patent…
AssigneeSociete Miniere et Metallurgique de Penarroya
InventorsJean-Michel Demarthe, Louis Gandon, Andre Georgeaux
Estimating the term…
The invention provides a method for selectively solubilizing the non-ferrous metals contained in sulphurized ores and concentrates, with regard to the iron and sulphur therein, by subjecting the ore or concentrate to lixiviation with an aqueous solution of cupric chloride at a temperature above 50.degree. C., preferably at a temperature between 70.degree. C. and 105.degree. C., and then regenerating said aqueous solution in situ at atmospheric pressure by means of air and a regeneration agent selected from the group consisting of hydrochloric acid and ferrous chloride. The invention also contemplates the preferable inclusion in the aqueous cupric chloride solution of an agent for solubilizing cuprous chloride selected from the group consisting of an alkali metal chloride, an alkaline earth metal chloride, ammonium chloride, and ferrous chloride. When the regeneration agent is hydrochloric acid, the pH of the aqueous cupric chloride solution is at most 1 in the presence of ferrous chloride and at most 3 in the absence of ferrous chloride. When the regeneration agent is ferrous chloride, the pH of the aqueous cupric chloride solution ranges between 1 and 3, the temperature of the solution exceeds 50.degree. C., and the solution contains at least 1g/l of cuprous ions and at least 2g/l of ferrous ions, with the result that geothite is precipitated and may be separated, and the non-ferrous metals isolated as the aqueous solutions of the metal chlorides.
A method for selectively solubilizing at least one non-ferrous metal selected from the group consisting of lead, zinc, copper, silver, cadmium, nickel, and cobalt, and contained, in the form of its sulphide, in an initial product selected from the group consisting of sulphurized ores and concentrates, comprising subjecting said initial product to lixiviation at a temperature above 50.degree. C. with an aqueous solution containing cupric chloride and an agent for solubilizing cuprous chloride, the aqueous solution having an oxido-reduction potential of between 400 and 800 millivolts in relation to a hydrogen electrode potential throughout the operation, whereby the metal sulphides are converted to the respective soluble metal chlorides, the cupric chloride is reduced to cuprous chloride which remains in solution due to said solubilizing agent, and elemental sulfur is produced, and regenerating the resulting reaction mixture in situ at atmospheric pressure and at a temperature above 50.degree. C. with air and hydrochloric acid while maintaining the pH of the solution at a value of at most 1 when the solution contains ferrous chloride and at a value of at most 3 when ferrous chloride is absent, whereby the cuprous chloride is oxidized to cupric chloride, and isolating an aqueous solution containing said at least one non-ferrous metal chloride.
A method for selectively solubilizing at least one non-ferrous metal selected from the group consisting of lead, zinc, copper, silver, cadmium, nickel, and cobalt, and contained, in the form of its sulphide, in an initial product selected from the group consisting of sulphurized ores and concentrates, comprising subjecting said initial product to lixiviation at a temperature above 50.degree. C. with an aqueous solution containing cupric chloride and an agent for solubilizing cuprous chloride, the aqueous solution having an oxido-reduction potential of between 400 and 800 millivolts in relation to a hydrogen electrode potential throughout the operation, whereby the metal sulphides are converted to the respective soluble metal chlorides, the cupric chloride is reduced to cuprous chloride which remains in solution due to said solubilizing agent, and elemental sulphur is produced, separating the sulphur and any unreacted residue from the reaction mixture, regenerating the resulting solution, containing at least 1 g/l of cuprous ions and at least 2 g/l of ferrous ions, in situ at atmospheric pressure and at a temperature above 50.degree. C. with air and ferrous chloride at a pH between 1 and 3, whereby goethite is precipitated, separating the goethite from the solution, and isolating an aqueous solution containing said at least one non-ferrous metal chloride.
Dependencies are inferred from the claim text.