Patent Number: 
Section: claims

1. A method of separating an amount of osmium from a mixture comprising the amount of osmium and at least one additional metal, the method comprising:contacting the mixture with an oxidizing solution to form a volatile OsO4 vapor;bubbling the OsO4 vapor through a KOH trapping solution to form an amount of K2[OsO4(OH)2] dissolved in the KOH trapping solution;contacting the dissolved K2[OsO4(OH)2] with a reducing agent to form an Os precipitate; andseparating the Os precipitate from the KOH trapping solution, wherein the mixture is an irradiated osmium metal target comprising at least one osmium isotope selected from the group consisting of Os-184, Os-186, Os-187, Os-188, Os-189, Os-190, and Os-192. 2. The method of claim 1, wherein:the mixture is an irradiated osmium metal target comprising at least one of Os-189, or Os-192; andthe at least one additional metal comprises at least one of Re-186, Ir-186, Ir-187, Ir-188, or Ir-190. 3. A method of separating an amount of osmium from a mixture comprising the amount of osmium and at least one additional metal, comprising:contacting the mixture with an aqueous solution of NaClO at a concentration of about 12% w/v available chlorine to form a volatile OsO4 vapor;bubbling the OsO4 vapor through a trapping solution comprising an aqueous solution of KOH at a concentration of about 25% w/v to form an amount of dissolved K2[OsO4(OH)2];contacting the dissolved K2[OsO4(OH)2] with an aqueous solution of NaHS at a concentration of about 10% w/v to form an OsS2 precipitate;washing the OsS2 precipitate by agitating with water;separating the OsS2 precipitate from the KOH trapping solution by centrifuging;rinsing the OsS2 precipitate with acetone; anddrying the OsS2 precipitate;wherein the mixture is an irradiated osmium metal target comprising at least one osmium isotope selected from the group consisting of Os-184, Os-186, Os-187, Os-188, Os-189, Os-190, and Os-192. 4. The method of claim 3, wherein:the mixture is an irradiated osmium metal target comprising at least one of Os-189, or Os-192; andthe at least one additional metal comprises at least one of Re-186, Ir-186, Ir-187, Ir-188, or Ir-190. 5. A method of separating an amount of osmium from a mixture comprising the amount of osmium and at least one additional metal, the method comprising:a. contacting the mixture with an oxidizing solution to form a volatile OsO4 vapor;b. bubbling the OsO4 vapor through a KOH trapping solution to form an amount of K2[OsO4(OH)2] dissolved in the KOH trapping solution;c. contacting the dissolved K2[OsO4(OH)2] with a reducing agent to form an Os precipitate; andd. separating the Os precipitate from the KOH trapping solution,wherein the oxidizing solution comprises an aqueous solution of an oxidizing agent chosen from NaClO, LiClO, KClO, NalO4, Na2S4O8, XeO3, NaClO2, NaClO3, NaClO4, NaOH in contact with Cl2 gas, alkali salts of ClO, ClO2, ClO3 and ClO4, or combinations thereof. 6. The method of claim 5, wherein the mixture is an irradiated Os-190 metal target, the amount of osmium comprises an amount of Os-191, and the at least one additional metal is chosen from Ir-192, Ir-193, Ir-194, Pt-192, Pt-194, or combinations thereof. 7. The method of claim 5, wherein the oxidizing solution is an aqueous solution of NaClO at a concentration of about 12% w/v available chlorine. 8. The method of claim 7, wherein the mixture is contacted with the oxidizing solution in an impinger device. 9. The method of claim 7, wherein the mixture is contacted with the oxidizing solution at a temperature of about 40° C. until the mixture is dissolved, and the dissolved mixture is contacted with the oxidizing solution at a temperature of about 90° C. 10. The method of claim 5, wherein the KOH trapping solution comprises an aqueous solution of KOH at a concentration of about 25% w/v. 11. The method of claim 10, wherein the KOH trapping solution is maintained at a temperature of less than about 5° C. 12. The method of claim 5, wherein the reducing agent is chosen from absolute ethanol, Zn shavings, Al shavings, Mg shavings, NaBH4, NaHS, H2S gas, Na2S2O3, UV light, phosphine ligands, hydrazine, hydroquinone, hydrophosphorous acid, formaldehyde, hydroxylamine, or citrate. 13. The method of claim 12, wherein the reducing agent is absolute ethanol at a concentration of 5% v/v and the Os precipitate is K2[OsO2(OH)4]. 14. The method of claim 12, wherein the reducing agent is a mixture of Zn shavings and Al shavings, and the Os precipitate is Os metal. 15. The method of claim 12, wherein the reducing agent is chosen from Zn shavings, Mg shavings, or Al shavings, the reducing agent is contacted with the dissolved K2[OsO4(OH)2] in combination with HCl, and the Os precipitate is Os metal. 16. The method of claim 12, wherein the reducing agent is NaBH4 and the Os precipitate is Os metal. 17. The method of claim 12, wherein the reducing agent is chosen from NaHS, H2S gas, or Na2S2O3 and the Os precipitate is OsS2. 18. The method of claim 5, wherein a remaining mixture in the oxidizing solution is contacted with a reducing agent to form an osmium-free mixture comprising the at least one additional metal. 19. A method of separating an amount of osmium from a mixture comprising the amount of osmium and at least one additional metal, comprising:a. contacting the mixture with an aqueous solution of NaClO at a concentration of about 12% w/v available chlorine to form a volatile OsO4 vapor;b. bubbling the OsO4 vapor through a trapping solution comprising an aqueous solution of KOH at a concentration of about 25% w/v to form an amount of dissolved K2[OsO4(OH)2];c. contacting the dissolved K2[OsO4(OH)2] with an aqueous solution of NaHS at a concentration of about 10% w/v to form an OsS2 precipitate;d. washing the OsS2 precipitate by agitating with water;e. separating the OsS2 precipitate from the KOH trapping solution by centrifuging;f. rinsing the OsS2 precipitate with acetone; andg. drying the OsS2 precipitate. 20. The method of claim 19, wherein the mixture is an irradiated Os-190 metal target, the amount of osmium comprises an amount of Os-191, and the at least one metal is chosen from Ir-192, Ir-193, Ir-194, Pt-192, Pt-194, or combinations thereof. 21. The method of claim 19, wherein the mixture is contacted with the aqueous solution of NaClO at a temperature of about 40° C. until completely dissolved, and the dissolved mixture is contacted with the aqueous solution of NaClO at a temperature of about 90° C. 22. The method of claim 21, wherein the dissolved mixture is contacted with the aqueous solution of NaClO until the aqueous solution of NaClO is colorless. 23. The method of claim 19, wherein the trapping solution is situated within an ice bath while the dissolved K2[OsO4(OH)2] is forming.