# US 12,110,573 B2 · Sulfide reactive vacuum distillation, absorption, stripping, and extraction for metal and alloy production > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,110,573 B2 - Document ID: US12110573B2 - Status: Granted - Kind: B2 - Application number: 18/384,722 - Filed: 2023-10-27 - Published: 2024-02-15 - Granted: 2024-10-08 - Earliest claimed: 2021-06-30 - Assignees: Massachusetts Institute of Technology - Applicants: Massachusetts Institute of Technology (MIT) - Inventors: Antoine Allanore; Caspar R. Stinn - Web page: https://patentgrep.com/patent/US12110573B2 ## CPC - C22B 5/04: by aluminium, other metals or silicon - C22B 9/02: Refining by liquating, filtering, centrifuging, distilling, or supersonic wave action {including acoustic waves; (C22B9/003, C22B9/006, C22B9/05, C22B9/22 take precedence)} - C22B 9/04: Refining by applying a vacuum - C22B 59/00: Obtaining rare earth metals - Y02P 10/20: Recycling - C22B: PRODUCTION AND REFINING OF METALS (electrolytic C25); PRETREATMENT OF RAW MATERIALS - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract In accordance with one embodiment, a method comprises dissolving a sulfide of a first metal in a solvent comprising molten aluminum; aluminothermically reduce at least a portion of the sulfide through reactive vacuum distillation to form gaseous aluminum sulfide distillate and elemental first metal that remains in the molten aluminum; and at least one of (e.g., one, two, or all three of) (a) reacting the aluminum sulfide distillate with at least one material in the molten aluminum; (b) reacting the aluminum sulfide distillate with at least one material outside of the molten aluminum; or (c) condensing the gaseous aluminum sulfide distillate. ## Claims ### Claim 1 A method comprising: dissolving at least a portion of a sulfide of a first metal in a solvent comprising molten aluminum; aluminothermically reducing at least a portion of the sulfide through reactive vacuum distillation to form gaseous aluminum sulfide distillate and elemental first metal that remains in the molten aluminum; and reacting the aluminum sulfide distillate with at least one material in the molten aluminum. ### Claim 2 (depends on 1) The method according to claim 1, wherein the process produces an alloy comprising at least aluminum and the first metal, optionally also including vacuum distilling a metal from the alloy and optionally reacting the distillate metal with gaseous sulfur to form a volatile sulfide. ### Claim 3 (depends on 1) The method according to claim 1, further comprising at least one of: recovering at least some of the first metal from the molten aluminum; oxidizing at least some of the first metal in the molten aluminum; or adding a third metal or a compound of the third metal to the molten aluminum to produce an alloy including the third metal and at least one of aluminum or the first metal, optionally wherein at least one of: (a) the compound of the third metal is aluminothermically reduced; or (b) the compound of the third metal is thermally reduced. ### Claim 4 (depends on 1) The method according to claim 1, wherein the molten aluminum includes a mixture of the first metal sulfide and at least one oxide, the process extracting the sulfide from the surrounding oxide via selective aluminothermic reduction of the sulfide. ### Claim 5 (depends on 1) The method according to claim 1, wherein the molten aluminum comprises at least one other element that forms at least one gaseous volatile sulfide that in turn assists the aluminum in reduction, optionally also selectively condensing at least one of the at least one gaseous volatilized sulfide. ### Claim 6 (depends on 1) The method according to claim 1, wherein reacting the aluminum sulfide distillate with at least one material in the molten aluminum comprises at least one of reactive stripping or reactive absorption. ### Claim 7 (depends on 1) The method according to claim 1, further comprising: selectively sulfidizing the first metal to form the first metal sulfide that is at least partially dissolved in the solvent comprising molten aluminum. ### Claim 8 A method comprising: dissolving at least a portion of a sulfide of a first metal in a solvent comprising molten aluminum; aluminothermically reducing at least a portion of the sulfide through reactive vacuum distillation to form gaseous aluminum sulfide distillate and elemental first metal that remains in the molten aluminum; and reacting the aluminum sulfide distillate with at least one material outside of the molten aluminum. ### Claim 9 (depends on 8) The method according to claim 8, wherein the process produces an alloy comprising at least aluminum and the first metal, optionally also including vacuum distilling a metal from the alloy and optionally reacting the distillate metal with gaseous sulfur to form a volatile sulfide. ### Claim 10 (depends on 8) The method according to claim 8, further comprising at least one of: recovering at least some of the first metal from the molten aluminum; oxidizing at least some of the first metal in the molten aluminum; or adding a third metal or a compound of the third metal to the molten aluminum to produce an alloy including the third metal and at least one of aluminum or the first metal, optionally wherein at least one of: (a) the compound of the third metal is aluminothermically reduced; or (b) the compound of the third metal is thermally reduced. ### Claim 11 (depends on 8) The method according to claim 8, wherein the molten aluminum includes a mixture of the first metal sulfide and at least one oxide, the process extracting the sulfide from the surrounding oxide via selective aluminothermic reduction of the sulfide. ### Claim 12 (depends on 8) The method according to claim 8, wherein the molten aluminum comprises at least one other element that forms at least one gaseous volatile sulfide that in turn assists the aluminum in reduction, optionally also selectively condensing at least one of the at least one gaseous volatilized sulfide. ### Claim 13 (depends on 8) The method according to claim 8, further comprising: selectively sulfidizing the first metal to form the first metal sulfide that is at least partially dissolved in the solvent comprising molten aluminum. ### Claim 14 A method comprising: dissolving at least a portion of a sulfide of a first metal in a solvent comprising molten aluminum; aluminothermically reducing at least a portion of the sulfide through reactive vacuum distillation to form gaseous aluminum sulfide distillate and elemental first metal that remains in the molten aluminum; and condensing the gaseous aluminum sulfide distillate. ### Claim 15 (depends on 14) The method according to claim 14, wherein the process produces an alloy comprising at least aluminum and the first metal, optionally also including vacuum distilling a metal from the alloy and optionally reacting the distillate metal with gaseous sulfur to form a volatile sulfide. ### Claim 16 (depends on 14) The method according to claim 14, further comprising at least one of: recovering at least some of the first metal from the molten aluminum; oxidizing at least some of the first metal in the molten aluminum; or adding a third metal or a compound of the third metal to the molten aluminum to produce an alloy including the third metal and at least one of aluminum or the first metal, optionally wherein at least one of: (a) the compound of the third metal is aluminothermically reduced; or (b) the compound of the third metal is thermally reduced. ### Claim 17 (depends on 14) The method according to claim 14, wherein the molten aluminum includes a mixture of the first metal sulfide and at least one oxide, the process extracting the sulfide from the surrounding oxide via selective aluminothermic reduction of the sulfide. ### Claim 18 (depends on 14) The method according to claim 14, wherein the molten aluminum comprises at least one other element that forms at least one gaseous volatile sulfide that in turn assists the aluminum in reduction, optionally also selectively condensing at least one of the at least one gaseous volatilized sulfide. ### Claim 19 (depends on 14) The method according to claim 14, further comprising: selectively sulfidizing the first metal to form the first metal sulfide that is at least partially dissolved in the solvent comprising molten aluminum.