US 12,291,761 B2
Solid-liquid-solid method for the solubilisation of copper minerals and concentrates, independent of the redox potential and with low consumption of water and acid
Rodrigo Andrés Cortés Cortés, Región Metropolitana (CL)
Assigned to NOVA MINERALIS S.A., Santiago (CL)
Appl. No. 17/292,573
Filed by NOVA MINERALIS S.A., Santiago (CL)
PCT Filed Nov. 14, 2018, PCT No. PCT/IB2018/058969
§ 371(c)(1), (2) Date May 10, 2021,
PCT Pub. No. WO2020/099912, PCT Pub. Date May 22, 2020.
Prior Publication US 2022/0042139 A1, Feb. 10, 2022
Int. Cl. C22B 15/00 (2006.01); C22B 3/08 (2006.01); C22B 3/10 (2006.01)
CPC C22B 15/0069 (2013.01) [C22B 3/08 (2013.01); C22B 3/10 (2013.01); C22B 15/0071 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A method for the solubilization of metals from ores and/or concentrates of sulphide ores of primary and/or secondary origin comprising said metals, wherein said method comprises sequential and/or overlapped steps as follows:
I. Moistening and Solvation, which corresponds to a step in a non-oxidative environment, where the ore or concentrate is moisten by addition of water; sulfuric acid in an amount of up to 15 kg per ton of ore; sodium chloride in an amount that ranges from 60 to 80 kg per ton of ore, without adding oxidizing or reducing agents, wherein this step includes the contact of the ore or concentrate with recirculating solutions that contain chloride, iron and copper ions, in an unsaturated environment and a final moisture of at least 8%;
II. Selective Transformation and solid-liquid-solid Precipitation, which corresponds to a chemical and physical step that does not depend on the redox potential and it is carried out in a pH ranging between 0.5 and 7, wherein the ore or concentrate in the presence of water, or water and acid is transformed into soluble species of copper, which precipitate on the ore or concentrate, being this step carried out under a condition of chloride supersaturation, a condition that is achieved by periods of non-irrigation and evaporation, through non-irrigation periods for a time ranging from 5 to 90 days, at room temperature; favoring the phenomena of haloclasty and crystallization of salts; without air injection and without aeration by constant irrigation; where the final moisture content is 6 to 10%; and
III. Acid-Chlorinated Washing, which corresponds to a non-oxidative washing step, where an acidulated solution is added with or without sodium chloride at a rate of 7 L/h/m2, where the sodium chloride is at a concentration of 120 to 200 g/L and where the pH of the solution is between 0.5 to 6 in order to remove the soluble copper species precipitated in the second step of the process; furthermore, a concentration of chloride and moisture to the ore or concentrate bed is restored,
wherein the three steps are carried out independently of the redox potential of the medium and repeated one or more times.