# US 2020/0399738 A1 · Method for clean metallurgy of molybdenum > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0399738 A1 - Document ID: US20200399738A1 - Status: Published application - Kind: A1 - Application number: 16/975,705 - Filed: 2019-04-26 - Published: 2020-12-24 - Earliest claimed: 2018-05-03 - Assignees: Central South University - Applicants: Central South University - Inventors: Zhongwei ZHAO; Yongli LI - Web page: https://patentgrep.com/patent/US20200399738A1 ## CPC - C22B 34/34: Obtaining molybdenum {(treatment or purification of solutions by adsorption on solids C22B3/24, by liquid-liquid extraction C22B3/26, by ion-exchange extraction C22B3/42; preparation of molybdenum involving liquid-liquid extraction, adsorption or ion-exchange C01G39/003)} - C01G 39/02: Oxides; Hydroxides - C22B 1/02: Roasting processes (C22B1/16 takes precedence) - C22B 3/06: in inorganic acid solutions {, e.g. with acids generated in situ; in inorganic salt solutions other than ammonium salt solutions} - C22B 3/065: {Nitric acids or salts thereof} - C22B 3/08: Sulfuric acid {, other sulfurated acids or salts thereof} - C22B 3/10: Hydrochloric acid {, other halogenated acids or salts thereof} - C22B 3/26: by liquid-liquid extraction using organic compounds - C22B 3/3842: {Phosphinic acid, e.g. H2P(O)(OH)} - C22B 3/3844: {Phosphonic acid, e.g. H2P(O)(OH)2} - C22B 3/3846: {Phosphoric acid, e.g. (O)P(OH)3} - C22B 3/44: by chemical processes (treatment or purification of solutions by liquid-liquid extraction C22B3/26, by ion-exchange extraction C22B3/42) - 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) - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract Disclosed is a method for clean metallurgy of molybdenum, including steps: 1) roasting molybdenite with calcium to obtain calcified molybdenum calcine, and leaching the calcified molybdenum calcine with an inorganic acid to obtain a molybdenum-containing inorganic acid leachate; 2) extracting molybdenum in the leachate with a cationic extractant to obtain an organic phase loaded with molybdyl cations and a raffinate; 3) using a hydrogen peroxide solution as a stripping agent to obtain a molybdenum stripping liquor; and 4) heating the molybdenum stripping liquor to dissociate peroxymolybdic acid therein so as to form a molybdic acid precipitate, and then calcining to obtain a molybdenum trioxide product. The method solves the problem of ammonia nitrogen wastewater production and can also be used for the enrichment and recovery of rhenium. ## Claims ### Claim 1 A method for clean metallurgy of molybdenum, comprising the following steps: 1) roasting molybdenite with calcium to obtain a calcified molybdenum calcine, and leaching the calcified molybdenum calcine with an inorganic acid to obtain a molybdenum-containing inorganic acid leachate; 2) extracting molybdenum in the molybdenum-containing inorganic acid leachate obtained in step 1) with a cationic extractant to obtain an organic phase loaded with molybdyl cations and a raffinate, wherein the cationic extractant is one or more of P204, P507 or Cyanex272; 3) using a hydrogen peroxide solution as a stripping agent, and mixing the hydrogen peroxide solution with the organic phase loaded with molybdyl cations to obtain a molybdenum stripping liquor; and 4) heating the molybdenum stripping liquor to dissociate peroxymolybdic acid therein so as to form a molybdic acid precipitate, and then calcining to obtain a molybdenum trioxide product. ### Claim 2 (depends on 1) The method for clean metallurgy of molybdenum according to claim 1, wherein step 1) is leaching with the inorganic acid under a normal pressure and at a temperature of 75 to 96° C., and the inorganic acid is one or more of sulfuric acid, nitric acid, and hydrochloric acid. ### Claim 3 (depends on 2) The method for clean metallurgy of molybdenum according to claim 2, wherein step 1) is leaching with the inorganic acid under the normal pressure and at a temperature of 85 to 95° C., and a leaching time is 2 h to 6 h. ### Claim 4 (depends on 1) The method for clean metallurgy of molybdenum according to claim 1, wherein in step 1), a concentration of the inorganic acid is 2 to 4 mol/L, and a leachate to solid ratio (L/Kg) is 3:1 to 10:1. ### Claim 5 (depends on 1) The method for clean metallurgy of molybdenum according to claim 1, wherein in step 2), the cationic extractant is prepared into a kerosene solution before being added, and a volume fraction of the cationic extractant in the kerosene solution is 10% to 50%. ### Claim 6 (depends on 1) The method for clean metallurgy of molybdenum according to claim 1, wherein the raffinate obtained in step 2) is recycled to step 1) for use after being supplemented with the inorganic acid consumed in a leaching process of step 1), and a recycling is carried out multiple times for an enrichment and recovery of rhenium. ### Claim 7 (depends on 1) The method for clean metallurgy of molybdenum according to claim 1, wherein in step 2), an extraction phase ratio (O/A) is 2:1 to 1:3; and multistage counter-current extraction is used, and a number of stages of extraction is 3 to 5. ### Claim 8 (depends on 1) The method for clean metallurgy of molybdenum according to claim 1, wherein in step 3), a mass concentration of the hydrogen peroxide solution is 10% to 20%, and a stripping phase ratio (O/A) is 3:1 to 5:1. ### Claim 9 (depends on 1) The method for clean metallurgy of molybdenum according to claim 1, wherein step 3) uses multistage counter-current stripping, and a number of stages of stripping is 2 to 5. ### Claim 10 (depends on 1) The method for clean metallurgy of molybdenum according to claim 1, wherein in step 4), the molybdenum stripping liquor is heated to 90 to 100° C. to dissociate a peroxygen bond therein. ### Claim 11 (depends on 2) The method for clean metallurgy of molybdenum according to claim 2, wherein step 3) uses multistage counter-current stripping, and a number of stages of stripping is 2 to 5. ### Claim 12 (depends on 3) The method for clean metallurgy of molybdenum according to claim 3, wherein step 3) uses multistage counter-current stripping, and a number of stages of stripping is 2 to 5. ### Claim 13 (depends on 4) The method for clean metallurgy of molybdenum according to claim 4, wherein step 3) uses multistage counter-current stripping, and a number of stages of stripping is 2 to 5. ### Claim 14 (depends on 5) The method for clean metallurgy of molybdenum according to claim 5, wherein step 3) uses multistage counter-current stripping, and a number of stages of stripping is 2 to 5. ### Claim 15 (depends on 6) The method for clean metallurgy of molybdenum according to claim 6, wherein step 3) uses multistage counter-current stripping, and a number of stages of stripping is 2 to 5. ### Claim 16 (depends on 7) The method for clean metallurgy of molybdenum according to claim 7, wherein step 3) uses multistage counter-current stripping, and a number of stages of stripping is 2 to 5. ### Claim 17 (depends on 8) The method for clean metallurgy of molybdenum according to claim 8, wherein step 3) uses multistage counter-current stripping, and a number of stages of stripping is to 5. ### Claim 18 (depends on 2) The method for clean metallurgy of molybdenum according to claim 2, wherein in step 4), the molybdenum stripping liquor is heated to 90 to 100° C., to dissociate a peroxygen bond therein. ### Claim 19 (depends on 3) The method for clean metallurgy of molybdenum according to claim 3, wherein in step 4), the molybdenum stripping liquor is heated to 90 to 100° C. to dissociate a peroxygen bond therein. ### Claim 20 (depends on 4) The method for clean metallurgy of molybdenum according to claim 4, wherein in step 4), the molybdenum stripping liquor is heated to 90 to 100° C., to dissociate a peroxygen bond therein.