# US 10,870,903 B2 · Process for leaching metal sulfides with reagents having thiocarbonyl functional groups > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,870,903 B2 - Document ID: US10870903B2 - Status: Granted - Kind: B2 - Application number: 16/743,949 - Filed: 2020-01-15 - Published: 2020-06-11 - Granted: 2020-12-22 - Earliest claimed: 2015-04-17 - Assignees: The University of British Columbia - Applicants: The University of British Columbia - Inventors: David Dixon; Edouard Asselin; Zihe Ren - Web page: https://patentgrep.com/patent/US10870903B2 ## CPC - C22B 3/08: Sulfuric acid {, other sulfurated acids or salts thereof} - C01G 1/00: Methods of preparing compounds of metals not covered by subclasses C01B, C01C, C01D, or C01F, in general (electrolytic production of inorganic compounds C25B1/00) - C01G 3/10: Sulfates - C01G 11/00: Compounds of cadmium - C01G 49/14: Sulfates {(C01G49/0018 takes precedence)} - C01G 53/10: Sulfates - C22B 3/18: with the aid of microorganisms or enzymes, e.g. bacteria or algae - C22B 3/20: Treatment or purification of solutions, e.g. obtained by leaching (C22B3/18 takes precedence) - C22B 3/42: by ion-exchange extraction - C22B 15/0071: {containing sulfur} - C22B 15/0089: {by chemical methods} - C22B 17/04: {by wet processes} - C22B 23/043: {Sulfurated acids or salts thereof} - C22B 23/0461: {by chemical methods} - C25C 1/12: of copper - C25C 1/08: of nickel or cobalt - C25C 1/16: of zinc, cadmium or mercury - Y02P 10/20: Recycling - C22B: PRODUCTION AND REFINING OF METALS (electrolytic C25); PRETREATMENT OF RAW MATERIALS - C01G: COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F (metal hydrides {monoborane, diborane or addition complexes thereof} C01B6/00; salts of oxyacids of halogens C01B11/00; peroxides, salts or peroxyacids C01B15/00; thiosulfates, dithionites, polythionates C01B17/64; compounds containing selenium, or tellurium C01B19/00; binary compounds of nitrogen with metals C01B21/06; azides C01B21/08; {compounds containing nitrogen, other non-metals and metal C01B21/082}; metal amides C01B21/092; nitrites C01B21/50; {compounds of noble gases C01B23/0005}; phosphides C01B25/08; salts of oxyacids of phosphorus C01B25/16; carbides C01B32/90; compounds containing silicon C01B33/00; compounds containing boron C01B35/00; compounds having molecular sieve properties but not having base-exchange properties C01B37/00; compounds having molecular sieve and base-exchange properties, e.g. crystalline zeolites, C01B39/00; cyanides C01C3/08; salts of cyanamide C01C3/16; thiocyanates C01C3/20) - C25C: PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract This application pertains to methods of recovering metals from metal sulfides that involve contacting the metal sulfide with an acidic sulfate solution containing ferric sulfate and a reagent that has a thiocarbonyl functional group, wherein the concentration of reagent in the acidic sulfate solution is sufficient to increase the rate of metal ion extraction relative to an acidic sulfate solution that does not contain the reagent, to produce a pregnant solution containing the metal ions. ## Claims ### Claim 1 A method of recovering at least one base metal from at least one base metal sulfide in a material, the method comprising: contacting a material comprising at least one base metal sulfide with an acidic sulfate solution comprising a reagent having a thiocarbonyl functional group, wherein the reagent is sodium dimethyldithiocarbamate (SDDC), to produce a pregnant solution containing base metal ions; and recovering the at least one base metal from the at least one base metal sulfide from the pregnant solution. ### Claim 2 (depends on 1) The method of claim 1, wherein the acidic sulfate solution further comprises ferric sulfate. ### Claim 3 (depends on 1) The method of claim 1, wherein the concentration of the reagent in the acidic sulfate solution is in the range of about 0.2 mM to about 30 mM. ### Claim 4 (depends on 1) The method of claim 1, wherein the concentration of the reagent in the acidic sulfate solution is in the range of about 0.2 mM to about 20 mM. ### Claim 5 (depends on 1) The method of claim 1, wherein the concentration of the reagent in the acidic sulfate solution is in the range of about 0.2 mM to about 10 mM. ### Claim 6 (depends on 1) The method of claim 1, wherein the concentration of the reagent in the acidic sulfate solution is in the range of about 0.2 mM to about 5 mM. ### Claim 7 (depends on 1) The method of claim 1, wherein the concentration of the reagent in the acidic sulfate solution is in the range of about 0.2 mM to about 4 mM. ### Claim 8 (depends on 1) The method of claim 1, wherein the concentration of the reagent in the acidic sulfate solution is in the range of about 0.2 mM to about 3 mM. ### Claim 9 (depends on 1) The method of claim 1, wherein the concentration of the reagent in the acidic sulfate solution is in the range of about 0.2 mM to about 2 mM. ### Claim 10 (depends on 1) The method of claim 1, wherein the concentration of the reagent in the acidic sulfate solution is in the range of about 0.2 mM to about 1.5 mM. ### Claim 11 (depends on 1) The method of claim 1, wherein the concentration of the reagent in the acidic sulfate solution is in the range of about 0.2 mM to about 1.0 mM. ### Claim 12 (depends on 1) The method of claim 1, wherein the concentration of the reagent in the acidic sulfate solution is in the range of about 0.2 mM to about 0.5 mM. ### Claim 13 (depends on 1) The method of claim 1, wherein the at least one base metal sulfide includes at least one copper sulfide. ### Claim 14 (depends on 13) The method of claim 13, wherein the at least one copper sulfide includes chalcopyrite. ### Claim 15 (depends on 13) The method of claim 13, wherein the at least one copper sulfide includes covellite. ### Claim 16 (depends on 13) The method of claim 13, wherein the at least one copper sulfide includes bornite. ### Claim 17 (depends on 13) The method of claim 13, wherein the at least one copper sulfide includes enargite. ### Claim 18 (depends on 13) The method of claim 13, wherein the at least one copper sulfide includes a copper sulfide of the formula CuxSy wherein the x:y ratio is between 1 and 2. ### Claim 19 (depends on 13) The method of claim 13, wherein the at least one copper sulfide includes chalcocite. ### Claim 20 (depends on 13) The method of claim 13, wherein the at least one copper sulfide includes djurleite. ### Claim 21 (depends on 13) The method of claim 13, wherein the at least one copper sulfide includes digenite. ### Claim 22 (depends on 1) The method of claim 1, wherein the at least one base metal sulfide includes a cadmium sulfide. ### Claim 23 (depends on 22) The method of claim 22, wherein the cadmium sulfide is greenockite. ### Claim 24 (depends on 1) The method of claim 1, wherein the at least one base metal sulfide includes at least one nickel sulfide. ### Claim 25 (depends on 24) The method of claim 24, wherein the at least one nickel sulfide includes pentlandite. ### Claim 26 (depends on 24) The method of claim 24, wherein the at least one nickel sulfide includes violarite. ### Claim 27 (depends on 1) The method of claim 1, wherein the material is an ore. ### Claim 28 (depends on 1) The method of claim 1, wherein the material is a concentrate of the at least one base metal sulfide. ### Claim 29 (depends on 1) The method of claim 1, wherein the material comprises agglomerated particles. ### Claim 30 (depends on 1) The method of claim 1, wherein ferric ions are used to oxidize the metal sulfide. ### Claim 31 (depends on 30) The method of claim 30, wherein the ferric ions are generated at least in part by bacteria. ### Claim 32 (depends on 1) The method of claim 1, wherein the method is a percolation leach. ### Claim 33 (depends on 32) The method of claim 32, wherein the percolation leach is a heap leach. ### Claim 34 (depends on 1) The method of claim 1, wherein the leach is a vat leach. ### Claim 35 (depends on 1) The method of claim 1, wherein the method is a tank leach. ### Claim 36 (depends on 1) The method of claim 1, wherein the method is a column leach. ### Claim 37 (depends on 1) The method of claim 1, wherein recovering the at least one base metal from the pregnant solution comprises solvent extraction and electrowinning. ### Claim 38 (depends on 1) The method of claim 1, further comprising maintaining the operating potential of the acidic sulfate solution above 500 mV vs Ag/AgCl.