Claims
- 1. A process for recovering nickel values form manganese sea nodules, said process comprising:
- a. comminuting said nodules;
- b. subjecting the comminuted nodules to a reducing roast to convert the nickel values to nickel metal;
- c. cooling the reduced nodules under non-oxidizing conditions;
- d. oxidatively leaching said reduced nodules with an aqueous ammoniacal ammonium carbonate solution having a molar ratio of ammonia to metal of from 0:1 to 100:1 by injecting an oxygen-containing gas into a slurry of said reduced nodules in said aqueous ammoniacal ammonium carbonate solution;
- e. contacting the resultant leach solution containing nickel ammonium salt complexes with a carbon monoxide-containing gas at a temperature of from about 50.degree. to about 250.degree.C and a pressure of from about 50 to about 3000 psig whereby the nickel values are reduced to nickel carbonyl;
- f. separating said nickel carbonyl from said leach solution; and
- g. decomposing said nickel carbonyl to metallic nickel.
- 2. A process of claim 1 wherein the molar ratio of ammonia to metal in said ammoniacal ammonium carbonate solution in said step (d) is from 0:1 to 10:1.
- 3. A process of claim 1 wherein said temperature in said step (e) is from about 100.degree. to about 175.degree.C.
- 4. A proccess of claim 1 wherein said contacting in said step (e) is carried out at a pressure of from about 50 to about 1800 psig.
- 5. A process of claim 1 wherein said contacting in said step (e) is carried out in the presence of a catalytic amount of a ligand selected from the group consisting of cyanide, sulfide, cysteine and tartrate.
- 6. A process of claim 5 wherein said ligand is present at a ratio of from about 0.01 to about 1 mole of said ligand per mole of said nickel.
- 7. A process of claim 1 wherein said contacting in said step (e) is carried out in the presence of a catalytic amount of a cyanide ligand and said cyanide ligand is present at a ratio of from 0.01 to 0.5 mole of said cyanide ligand per mole of said nickel.
- 8. A process of claim 1 wherein said carbon monoxide-containing gas in said step (e) is selected from the group consisting of carbon monoxide and synthesis gas.
- 9. A process of claim 1 wherein said carbon monoxide-containing gas in said step (e) is carbon monoxide.
- 10. A process of claim 1 wherein said contacting in said step (e) is carried out in the presence of an essentially water-immiscible, substantially inert solvent for nickel carbonyl, whereby said nickel carbonyl is concentrated in said solvent.
- 11. A process of claim 1 wherein said contacting in said step (e) is carried out in the presence of an essentially water-immiscible, substantially inert solvent for nickel carbonyl which is a saturated aliphatic hydrocarbon, whereby said nickel carbonyl is concentrated in said saturated aliphatic hydrocarbon solvent.
- 12. A process of claim 1 wherein said nickel carbonyl is separated in said step (f) from said solution by passing a carbon monoxide-containing gas through said solution, allowing said nickel carbonyl to vaporize into said carbon monoxide-containing gas and subsequently passing said carbon monoxide-containing gas into a thermal decomposition zone, wherein said nickel carbonyl contained in said carbon monoxide-containing gas is decomposed to metallic nickel according to said step (g).
- 13. A process of claim 1 wherein said manganese sea nodules contain recoverable amounts of nickel, copper, and cobalt, said process comprising:
- a. comminuting said manganese nodules;
- b. subjecting the comminuted nodules to a reducing roast to convert the nickel, copper, and cobalt to nickel metal, copper metal, and cobalt metal;
- c. cooling the reduced nodules under non-oxidizing conditions;
- d. oxidatively leaching said reduced nodules with an aqueous ammoniacal ammonium carbonate solution having a molar ratio fo ammonia to metal of from 0:1 to 100:1 by injecting an oxygen-containing gas into a slurry of said reduced nodules in said aqueous ammoniacal ammonium carbonate solution;
- e. contacting the resultant leach solution containing nickel, copper, and cobalt ammonium salt complexes with a carbon monoxide-containing gas at a temperature of from about 50.degree.to about 250.degree.C and a pressure of from about 50 to about 3000 psig whereby the nickel, copper, and cobalt values are reduced to nickel carbonyl, metallic copper, and cobalt tetracarbonyl anion;
- f. separating said nickel carbonyl from said leach solution;
- g. decomposing said nickel carbonyl to metallic nickel;
- h. recovering said metallic copper;
- i. separating said cobalt from said leach solution by injecting an oxygen-containing gas into said solution whereby said cobalt tetracarbonyl anion is oxidized to hydrated cobalt oxide; and
- j. heating said hydrated cobalt oxide at a temperature sufficient to drive off the waters of hydration to produce cobalt oxide.
Parent Case Info
This is a division of application Ser. No. 55,850, filed July 17, 1970, now U.S. Pat. No. 3,775,099 which in turn is a continuation-in-part of application Ser. No. 717,034, filed Mar. 28, 1968 and Ser. No. 807,987, filed Mar. 17, 1969.
US Referenced Citations (4)
Foreign Referenced Citations (1)
Number |
Date |
Country |
583,571 |
Sep 1959 |
CA |
Divisions (1)
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Number |
Date |
Country |
Parent |
55850 |
Jul 1970 |
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Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
717034 |
Mar 1968 |
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