Claims
- 1. A method for recovering precious metal values from a refractory carbonaceous ore material including a carbonaceous component that has the propensity of retaining the precious metal values in the ore upon treatment of the ore material with a leachant or lixiviant for the precious metal values comprising
- a. inoculating the carbonaceous ore material with a carbon-deactivating microbial consortium
- b. incubating the inoculated material under conditions sufficient to reduce the propensity of the carbonaceous component to retain precious metal values,
- c. treating the incubated material with a leachant or lixiviant for the recovery of precious metal values and
- d. recovering the precious metal values
- 2. A method as defined in claim 1 wherein said ore material is in a heap formation.
- 3. A method as defined in claim 1 wherein said microbial consortium is grown in a nutrient medium, prior to inoculation for a period of about 7 to about 10 days.
- 4. A method as defined in claim 1 wherein said microbial consortium is provided with a consortium-metabolizable source of carbon.
- 5. A method as defined in claim 4 wherein said source of carbon comprises n-hexadecane kerosene or diesel fuel.
- 6. A method as defined in claim 1 wherein said microbial consortium is provided with an organic carboxylic acid source.
- 7. A method as defined by claim 6 wherein said carboxylic acid source comprises a citrate.
- 8. A method as defined in claim 1 wherein said microbial consortium is provided with a chelating agent.
- 9. A method as defined by claims 8 wherein said chelating agent comprises ethylene diamine tetracetic acid.
- 10. A method as defined by claim 1 wherein said microbial consortium is provided with a nutrient solution during incubation.
- 11. A method as defined by claim 10 wherein said nutrient solution is recirculated during incubation.
- 12. A method according to claim 1 wherein said ore comprises a particulate formed of biooxidized carbonaceous-sulfidic ore.
- 13. A method according to claim 1 wherein said incubation is conducted for a period of about 2 days to about 10 days at a temperature from about 15.degree. to about 35.degree. Celsius.
- 14. A method according to claim 1 wherein the method includes biooxidizing ore material after incubation and prior to treatment with a leachant or lixiviant.
- 15. A method according to claim 1 wherein the method includes biooxidizing ore material before inoculation.
- 16. A carbonaceous ore particulate having recoverable precious metal values and a precious metal value-absorbing carbon content including a carbon-deactivating microbial consortium
- 17. A carbonaceous-sulfidic ore particulate having recoverable precious metal values and a precious metal value-absorbing carbon content including a carbon-deactivating microbial consortium.
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part application of U.S. patent application Ser. No. 07/750,444, filed Aug. 20, 1991 now U.S. Pat. No. 5,127,942. That application is, in turn, a continuation of U.S. patent application Ser. No. 07/586,424, filed Sep. 21, 1990, now abandoned.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
5127942 |
Brierley |
Jul 1992 |
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Continuations (1)
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Number |
Date |
Country |
Parent |
586424 |
Sep 1990 |
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Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
750444 |
Aug 1991 |
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