GB419819A - Improvements relating to the dissolving of metals of the platinum group - Google Patents
Improvements relating to the dissolving of metals of the platinum groupInfo
- Publication number
- GB419819A GB419819A GB1390633A GB1390633A GB419819A GB 419819 A GB419819 A GB 419819A GB 1390633 A GB1390633 A GB 1390633A GB 1390633 A GB1390633 A GB 1390633A GB 419819 A GB419819 A GB 419819A
- Authority
- GB
- United Kingdom
- Prior art keywords
- bath
- platinum
- metal
- sodium
- potassium
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B11/00—Obtaining noble metals
- C22B11/08—Obtaining noble metals by cyaniding
Abstract
Metals of the platinum group are stripped from a metal foundation by immersing the article to be stripped in a bath comprising molten sodium cyanide and/or potassium cyanide, the platinum group metal and the foundation metal being such that the platinum group metal is preferentially attacked. To accelerate the action of the bath, an electric current may be used, the article to be stripped constituting the anode. In addition, one or more metals of the platinum group may be transferred from one or more articles to another article by making the article or articles containing or consisting of platinum &c. the anode, and the article on which the platinum &c. is to be deposited the cathode in an electrolytic bath comprising molten sodium and/or potassium cyanide. In the electrolytic forms of the process, the platinum &c. goes into solution at the anode at a greater rate than it is deposited at the cathode, a complex cyanogen compound of the platinum &c. accumulating in the bath. Inactive compounds such as sodium hydroxide or potassium hydroxide may be added to the bath to lower its melting temperature; potassium or sodium ferrocyanide may also be added to the bath, the effect of these additions being to lower the melting point and to yield a little iron in the cathode deposit. The process is preferably conducted under non-oxidizing conditions, say by using an inert atmosphere or by covering the bath with a protective layer such as a mixture containing graphite and plumbago. When cathodically depositing the platinum metals, a small quantity of the complex alkali metal cyanide of the platinum metal or metals under treatment is preferably added to the bath in order to accelerate the deposition. According to the examples, rhodium is stripped from silver by immersion in a molten bath at 500 DEG C. consisting of sodium and potassium cyanides; rhodium is stripped from copper in a bath at 440 DEG C. consisting of sodium and potassium cyanides and sodium hydroxide, the stripping being accelerated if an anodic current is passed through the metal article; a bath consisting of sodium and potassium cyanide is used to strip palladium or platinum from a silver foundation, ruthenium from copper and iridium from gold by immersion or anodic treatment; ruthenium is deposited on a gold cathode from an electrolyte consisting of sodium cyanide, potassium cyanide and potassium ruthenocyanide in a porcelain crucible in an atmosphere of nitrogen at 520--550 DEG C., a ruthenium anode being employed. Processes in which an electrolytic bath for the deposition of a platinum metal is made and periodically replenished by addition of an oxide of a platinum group metal to fused potassium cyanide, a platinum group metal being employed as an anode, are disclaimed. The Provisional Specification describes also the employment of molten baths comprising alkaline earth metal cyanides alone or in admixture with alkali metal cyanides and the use of sodium chloride as an addition to lower the melting point of the bath when articles having a silver foundation are treated.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB1390633A GB419819A (en) | 1933-05-12 | 1933-05-12 | Improvements relating to the dissolving of metals of the platinum group |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB1390633A GB419819A (en) | 1933-05-12 | 1933-05-12 | Improvements relating to the dissolving of metals of the platinum group |
Publications (1)
Publication Number | Publication Date |
---|---|
GB419819A true GB419819A (en) | 1934-11-12 |
Family
ID=10031519
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB1390633A Expired GB419819A (en) | 1933-05-12 | 1933-05-12 | Improvements relating to the dissolving of metals of the platinum group |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB419819A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3257299A (en) * | 1961-09-26 | 1966-06-21 | Hooker Chemical Corp | Composition and method for electrolytic stripping of coatings from metals |
-
1933
- 1933-05-12 GB GB1390633A patent/GB419819A/en not_active Expired
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3257299A (en) * | 1961-09-26 | 1966-06-21 | Hooker Chemical Corp | Composition and method for electrolytic stripping of coatings from metals |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3654099A (en) | Cathodic activation of stainless steel | |
US3309292A (en) | Method for obtaining thick adherent coatings of platinum metals on refractory metals | |
US2093406A (en) | Stripping or transferring platinum metals | |
US4126522A (en) | Method of preparing aluminum wire for electrical conductors | |
US3554881A (en) | Electrochemical process for the surface treatment of titanium,alloys thereof and other analogous metals | |
US3238112A (en) | Electroplating of metals using mercapto-metal complex salts | |
US2311139A (en) | Process for the electrolytic cleaning of metals | |
US3867265A (en) | Process for electroplating an aluminum wire | |
GB419819A (en) | Improvements relating to the dissolving of metals of the platinum group | |
US3505181A (en) | Treatment of titanium surfaces | |
US3235392A (en) | Electroless deposition of palladium | |
US1566984A (en) | Electroplating method and electroplated articles | |
US1991995A (en) | Platinum metal ammino cyanide plating bath and process for electrodeposition of platinum metal therefrom | |
US1827142A (en) | Process for the treatment of aluminum | |
US1417896A (en) | Electrodeposition of metals upon iron and alloys of iron | |
GB1163491A (en) | Surface Treatment of Ferrous Metals | |
US2809929A (en) | Anode for copper plating | |
US2457021A (en) | Palladium plating | |
US2199391A (en) | Process of gold refining | |
GB1082695A (en) | Improvements in the electroplating of precious metals on to articles made of baser metals | |
SU103185A1 (en) | The composition of the electrolyte bath for the deposition of lead-indium alloy | |
GB760084A (en) | Improvements in and relating to the electrodeposition of antimony | |
US1515712A (en) | Mercury zinc anode for sulphate solutions | |
US1133628A (en) | Galvanizing wire, hoops, sheets, and the like. | |
US1374541A (en) | Electrolytic process |