US4421724A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Extraction method for refractory precious metal ore
Assignee: ANGLO MINERAL RESOURCES Inc A CORP OF
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Filing: 1981-09-08
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Granted: 1983-12-20
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Expires: 2001-09-08
Abstract
Abstract Cyanic extraction of precious metal from comminuted, refractory precious metal ore as well as refractory precious metal concentrates and tailings from such ore is effected with rapidity and high yield by agitationally treating the refractory material with an aerated, alkaline solution containing a high concentration of water soluble cyanide and a low concentration of chemical oxidizer such as potassium permanganate.
Inventors
- 👤 Larry B. Hunnel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:57
CPC Classifications
C; C22; C22B; C22B11/00; C22B11/08
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
90 words
A method for effecting cyanic extraction of precious metal from comminuted, refractory precious metal ore, which comprises: agitationally treating said ore with an aerated, alkaline solution containing (a) water soluble cyanide in an amount from about 112 to about 336 grams of cyanide ion per gallon of solution and (b) chemical oxidizer in an amount from about 0.5 to about 10 grams per gallon of solution, wherein the weight per gallon ratio of ore to solution is from about 500 to about 10,000 grams of ore per gallon of solution.
Claim 2
Independent Claim
90 words
A method for effecting cyanic extraction of precious metal from comminuted, refractory precious metal ore, which comprises: agitationally treating said ore with an aerated, alkaline solution containing (a) water soluble cyanide in an amount from about 112 to about 336 grams of cyanide ion per gallon of solution and (b) chemical oxidizer in an amount from about 0.5 to about 10 grams per gallon of solution, wherein the weight per gallon ratio of ore to solution is from about 500 to about 10,000 grams of ore per gallon of solution.
Claim 3
Dependent Claim
14 words
The method of claim 1 wherein the ore comprises a pyritic precious metal ore.
Claim 4
Dependent Claim
14 words
The method of claim 1 wherein the ore comprises an arsenical precious metal ore.
Claim 5
Dependent Claim
14 words
The method of claim 1 wherein the ore comprises a quartzitic precious metal ore.
Claim 6
Dependent Claim
26 words
The method of claim 1 wherein the concentration of water soluble cyanide is from about 168 to 280 grams of cyanide ion per gallon of solution.
Claim 7
Dependent Claim
20 words
The method of claim 1 wherein the water soluble cyanide is sodium cyanide, potassium cyanide, calcium cyanide, or mixtures thereof.
Claim 8
Dependent Claim
21 words
The method of claim 1 wherein the concentration of oxidizer is from about 0.6 to 8 grams per gallon of solution.
Claim 9
Dependent Claim
18 words
The method of claim 1 wherein the oxidizer is potassium permanganate, sodium permanganate, manganese dioxide or mixtures thereof.
Claim 10
Dependent Claim
16 words
The method of claim 1 wherein the solution has a pH of at least about 10.
Claim 11
Dependent Claim
17 words
The method of claim 1 wherein the solution has a pH from about 11 to about 13.
Claim 12
Dependent Claim
19 words
The method of claim 1 wherein the solution is at a temperature from about 21° to about 50° C.
Claim 13
Dependent Claim
16 words
The method of claim 1 wherein the comminuted ore has particle size less than 80 mesh.
References Cited (Backward Citations)
US483766A
Cited
US4038362A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-12-19 | 1987-06-20 | 1987-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-19 | 1991-06-20 | 1991-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-19 | 1995-06-20 | 1995-12-20 | $7700.00 | Window Closed / Lapsed |