US4086084A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Refining of metals
Assignee: Matthey Rustenburg Refiners Pty Ltd
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Filing: 1975-03-18
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Granted: 1978-04-25
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Expires: 1995-03-18
Abstract
Abstract This invention relates to refining platinum group metal concentrates and the separation therefrom of silver and of the majority of base metals with which they naturally occur. In more detail the process comprises the steps of:
Inventors
- 👤 Raymond Edward Oliver
- 👤 John Blunden Payne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:27
CPC Classifications
C; C22; C22B; C22B9/00; C22B9/02; C22B1/00; C22B1/02; C22B1/08; C22B11/00; C22B11/02; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
178 words
A process for refining a mineral concentrate which comprises a mixture of at least one precious metal selected from the group consisting of gold, ruthenium, rhodium, palladium, osmium, iridium and platinum; silver and a base metal which forms a volatile halide so as to separate the silver and base metal from the precious metal, said base metal being selected from the group consisting of Sb, Sn, Pb, Zn, Cu, Ni, Fe, As, Se and Te; said process comprising: (a) contacting the mixture of base metal, silver and precious metal, any of which may be in metallic or chemically combined form, while said mixture is maintained in solid particulate form with a halogen-containing gas selected from the group consisting of hydrogen chloride, hydrogen bromide, chlorine and bromine at a temperature below the melting point of the mixture but which is sufficiently high for the base metal and silver to form their halides and for the said halides substantially to volatilize from the said solid mixture, and (b) removing the said volatilized halides from the solid precious metal which remains.
Claim 2
Dependent Claim
178 words
A process for refining a mineral concentrate which comprises a mixture of at least one precious metal selected from the group consisting of gold, ruthenium, rhodium, palladium, osmium, iridium and platinum; silver and a base metal which forms a volatile halide so as to separate the silver and base metal from the precious metal, said base metal being selected from the group consisting of Sb, Sn, Pb, Zn, Cu, Ni, Fe, As, Se and Te; said process comprising: (a) contacting the mixture of base metal, silver and precious metal, any of which may be in metallic or chemically combined form, while said mixture is maintained in solid particulate form with a halogen-containing gas selected from the group consisting of hydrogen chloride, hydrogen bromide, chlorine and bromine at a temperature below the melting point of the mixture but which is sufficiently high for the base metal and silver to form their halides and for the said halides substantially to volatilize from the said solid mixture, and (b) removing the said volatilized halides from the solid precious metal which remains.
Claim 3
Dependent Claim
36 words
A process according to claim 1 in which the oxidising agent dissolved in the hydrochloric acid solution of step (c) is selected from the group consisting of chlorine, bromine, hypochlorite, hypobromite, sodium chlorate and sodium bromate.
Claim 4
Dependent Claim
25 words
A process according to claim 1 in which the halogen-containing gas also contains a gas selected from the group consisting of nitrogen argon and hydrogen.
Claim 5
Dependent Claim
23 words
A process according to claim 1 in which the solid particulate mixture is in the form of granules, pellets, powder, briquettes or tablets.
Claim 6
Dependent Claim
20 words
A process according to claim 4 in which the granules, pellets, powder, briquettes or tablets also contain a particulate filler.
Claim 7
Dependent Claim
21 words
A process according to claim 5 in which the particulate filler is a diatomaceous earth having silica as its main ingredient.
Claim 8
Dependent Claim
20 words
A process according to claim 1 in which the temperature of the halogen-containing gas is within the range 900°-1700° C.
Claim 9
Dependent Claim
20 words
A process according to claim 1 in which the reaction takes place at a temperature within the range 900°-1300° C.
Claim 10
Dependent Claim
22 words
A process according to claim 1 in which the reaction is carried out in a tubular vessel constructed of a refractory material.
Claim 11
Dependent Claim
24 words
A process according to claim 9 in which the refractory material is selected from the group consisting of silica, quartz, silicon nitride, and carbon.
Claim 12
Dependent Claim
168 words
A process for refining a mineral concentrate comprising a mixture of a precious metal selected from gold, ruthenium, rhodium, palladium, osmium, iridium and platinum; silver and one or more base metals selected from the group consisting of Sb, Sn, Pb, Zn, Cu, Ni, Fe, As, Se and Te which comprises: (a) contacting the mixture of base metal, silver and precious metal, any of which may be in metallic or chemically combined form, while said mixture is maintained in solid particulate form with a halogen-containing gas selected from the group consisting of hydrogen chloride, hydrogen bromide, chlorine and bromine at a temperature below the melting point of the mixture but which is sufficiently high for the base metal and silver to form their halides and for the said halides substantially to volatilize from the said solid mixture, (b) removing the said volatilized halides from the solid precious metal which remains, and then (c) dissolving the precious metal remaining after step (b) in hydrochloric acid solution containing an oxidizing agent.
Claim 13
Dependent Claim
168 words
A process for refining a mineral concentrate comprising a mixture of a precious metal selected from gold, ruthenium, rhodium, palladium, osmium, iridium and platinum; silver and one or more base metals selected from the group consisting of Sb, Sn, Pb, Zn, Cu, Ni, Fe, As, Se and Te which comprises: (a) contacting the mixture of base metal, silver and precious metal, any of which may be in metallic or chemically combined form, while said mixture is maintained in solid particulate form with a halogen-containing gas selected from the group consisting of hydrogen chloride, hydrogen bromide, chlorine and bromine at a temperature below the melting point of the mixture but which is sufficiently high for the base metal and silver to form their halides and for the said halides substantially to volatilize from the said solid mixture, (b) removing the said volatilized halides from the solid precious metal which remains, and then (c) dissolving the precious metal remaining after step (b) in hydrochloric acid solution containing an oxidizing agent.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-04-24 | 1981-10-24 | 1982-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-04-24 | 1985-10-24 | 1986-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-04-24 | 1989-10-24 | 1990-04-25 | $7700.00 | Window Closed / Lapsed |