Method of winning copper, nickel, and other metals

Claim 2

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° to about 250°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.

Claim 3

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.

Claim 4

A process of claim 1 wherein said temperature in said step (e) is from about 100° to about 175°C.

Claim 5

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.

Claim 6

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.

Claim 7

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.

Claim 8

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.

Claim 9

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.

Claim 10

A process of claim 1 wherein said carbon monoxide-containing gas in said step (e) is carbon monoxide.

Claim 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, whereby said nickel carbonyl is concentrated in said solvent.

Claim 12

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.

Claim 13

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).

Claim 14

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°to about 250°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.