US669442A - Process of recovering and separating metals by electrolysis. - Google Patents

Process of recovering and separating metals by electrolysis. Download PDF

Info

Publication number
US669442A
US669442A US3015400A US1900030154A US669442A US 669442 A US669442 A US 669442A US 3015400 A US3015400 A US 3015400A US 1900030154 A US1900030154 A US 1900030154A US 669442 A US669442 A US 669442A
Authority
US
United States
Prior art keywords
metals
electrolyte
anode
vessel
copper
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 - Lifetime
Application number
US3015400A
Inventor
Hans A Frasch
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US3015400A priority Critical patent/US669442A/en
Application granted granted Critical
Publication of US669442A publication Critical patent/US669442A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • CCHEMISTRY; METALLURGY
    • C25ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25CPROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
    • C25C1/00Electrolytic production, recovery or refining of metals by electrolysis of solutions
    • C25C1/12Electrolytic production, recovery or refining of metals by electrolysis of solutions of copper

Definitions

  • This invention relates to an electrolytic process of recovering and separating metals from bodiesof greater or less complexity, and more especially such as complex ores, matte, slags, (be.
  • I take the body containing the metals id be extracted and whether such body contains only these metals or others and utilize it in the form of .an anode as part of an electrolytic bath or a number of baths.
  • the cathode may consist of any usually-employed substance, and lprefor to use a cathode consisting of the same kind of metal as will be deposited upon it.
  • the object of my invention is to bring the metals represented in the anode in solution and by electrolyzing this solution depositing from it at a given tensiouof an electric current certain metals upon the cathodes, at the same time resaturating the electrolyte constantly by passing it repeatedly through anodes of the same composition, thereby continuously enriching the electrolyte more and more with such netals'as may be present in the anode in comparatively small proportions and which require for deposition an electric current of highertension, and, finally, by the complete deposition of the metals desired to be removed from the electrolyte a concentrated solution of the remaining metals is obtained, from which the latter may be removed by electrical or chemical means.
  • My invention is particularly applicable in the treatment of copper-nickel ore or matte. and bring the metals coutained therein into solution, i use the matte for anode in an electrolytic bath, in which a solution of a salt of an alkali forms the electrolyte, ordinary carbon or copper-cathodes being employed.
  • electrolysis I obtain caustic soda at the cathode and. a solution the corresponding salts of the metals of which,
  • the metallic solution th usohtained .1 subject to electrolysis in a series of baths, all having matte anodes and cathodes composed, preferably, of copper, the anodes of the baths consistingof disintegrated matte and arranged in such a manner that the metallic solution which forms the electrolyte passes through the'body of the anode and solution in this manner, and the sothrough a suitable diaphragm, past the cathodes, and through an overflow-onto the anode of the bath next in series, and soon through any desired number of baths.
  • the solvent agent represented in the electrolyte as liberated dissolving a'corresponding quantity of fresh metals from the metaLbe-aring anode of each bath, and by the repeated deposition of copper only and resaturation with the compound metals of the anode the electrolyte becomes more and more saturated with the other metals and impoverished in copper until eventuallyv a point of saturation is reached convenleut for the recovery of the metals other than copper.
  • the latter in its passage through thebath last in series is not allowed to pass the cathodes, but is brought to circulate through the anode only and below a diaphragm, permitting only enough of the electrolyte to pass through the diaphragm as will insure complete exhaustion of the copper still contained in the electrolyte at the cathodes.
  • the solution derived from the cathode-section of the bath last in series contains -then only nickel, iron, and cobalt.
  • the iron is removed from the solution by chemical treatment, and the nickel may be separated from the cobalt by electrolysis orby chemical means.
  • Figure l is a. sectional elevation.
  • Fizz. 2 is a diugrmn of a, double buttery.
  • the invention 1 use the term ore and the term metallifcrous body as including these various substances.
  • the vessels 1 and 4 at the beginning and end of-the series of electrolytic baths are alike and comprise suits-hie fluid-tight receptacles huving in their bottoms perforated pipesa, carbon or other conductors b, suitably wired to a source of electricity, at mass of the metallifc overlying the carbons and com stituting an anode, a diaphragm d of granular or equivalent permeable material, such as sand, placed upon the anode, a' vertical bridgewell e across one end of the receptacle and extending from its top nearly to its bottom,
  • an overflow-pipe f at one end, an overflowpipe g opening from the other side of the bridge-wall, and s cathode h, which may be.
  • vessels 2 and 3 composed of a series oi copper or other plates suitable to receive the selected metal or metals to be deposited. Between these two vessels may be arranged on y number of vessels 2 and 3 in all substantial respects like the vesselsl and 4, excepting that they have no bridgewslls end no overflows, hated g.
  • a water-tank i may be arranged to supply suchas those desigwstcr to the vessel 1, and the tank j may be arranged to supply the exciting fluid to the pipe a of the same vessel.
  • the pipes a, of the succeeding vessels are connected with the outlet of the next preceding vessel by hose or pipes k.
  • the overliow-pipeg of vessel 1 above the diaphragm lends to a tank I, and the pipe g of vessel t leads to s tank m, while the pipe of vessel 4 lends to u. tank n, which is connected with a pump or other forcing device 0, which returns the fluid to any of the vessels, es 2, through pipe p.
  • a diaphragm may be omitted in such vessels as 2 and 3 if the purity of the copper deposited is not an object.
  • I supply tank j with common-salt solution of it preferred strength-ssy about 20 permit this solution to flow through pipe a into vessel 1, through the anode c and diaphragm d therein, until the solution reaches the overflows f and y, when thevulve g of overflow g is closed'und the inflow of salt soand pass lotion is diminished and the salt solution ullowed to leave the vessel 1 through overflow into the second vessel in series.
  • the metallic-chlorid solution cathodes has accumu from tank 1, passing throughoverfiow f, is
  • valve 9 in the pipe g being closcd no circulation through the diaphragm in vessel 4 occurs, and thereby the electrolyte above the diaphragm becomes excapacity of the cathodes, so that while the ceases electrolyte coming from the anode and passing through the diaphragm still supplies copper it leaves vessel 4 by overflow g free from dilferent' com position.
  • the anodes in vessels 1, 2, and 3 may be composed of copper matte and in vessel 4 the anode may be composed of nickel-bearing iron slag or other metalliferous bodies or the anode in each of the vessels may be of
  • the electrolyte also may dilfer between the individual vessels, and it may be withdrawn from any vessel of the series and returned to the same or any other of the vessels, if sodesired. That part of the electrolyte supplying the cathode of the vessel 4 for the purpose of exhausting the last quantity of copper instead of passing through the diaphragm, as I prefer to do, may
  • the sulfur is recovered by distillation or other well-known mehods fromv the-residuum of the anode after the metals are extracted and forms a valuable by-product.
  • the method of recovering copper and separating nickel and cobalt from matte or ore, by electrolysis which consists in providing a number of electrolytic baths with permeable anodes composed of the material to be treated, electrolyzinn the salt of an alkali in the first of the series of baths and clr'culating the metal-bearing electrolyte thereby obtained successively through the anodes and past the cathodesof the baths next in series, thereby electrodepositing thecopper onto the cathodes of the successive baths and constantly enrichingthe electrolyte with nickel and cobalt, substantially as described.
  • the method of separating metals from their ores which consists in providing an electrolytic bath with a permeable anode co mposed of ore bearing the metals to be obtained and circulating through such anode and through a diaphragm to the cathode an elec trolyte capable of dissolving the-metals, and

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electrolytic Production Of Metals (AREA)

Description

No. 669,442. Patentedfl ar. 5, mm
H. A. EBASCH. {PROCESS OF REGOVERING AND SEPARATING'METALS BY ELEfITROLYSlS.
(Application filed Sept15 1900.)
(No Model.)
i i N W) 65565: 3.-
' To treat such matte HANS A. FRASCH, OF HAMILTON, CANADA.
PROCESS OFRECOVEFHNG AND SEPARATlNG METALS BY ELECTROLYSlS QZECIFICATION forming part of Letters Patent No. 869,442, dated March 5, v1 901.
Application filed September 15, 1900.
Aerial No. 30,154. (No specimens.)
To 6055 whom it may UUILG/HIZ:
Be it known thatl, HANS A. FRASCH, a citizen of the United States, residing at Hamilton, in thocountyot' Wentworth and Province of Ontario, Canada, have in vented a certain new and useful Improvement in Processes of Recovering and Separating Metals by Electrolysis, of which the following is a full, clear, and exact description.
This invention relates to an electrolytic process of recovering and separating metals from bodiesof greater or less complexity, and more especially such as complex ores, matte, slags, (be.
In carrying out my invention I take the body containing the metals id be extracted and whether such body contains only these metals or others and utilize it in the form of .an anode as part of an electrolytic bath or a number of baths. The cathode may consist of any usually-employed substance, and lprefor to use a cathode consisting of the same kind of metal as will be deposited upon it.
The object of my invention is to bring the metals represented in the anode in solution and by electrolyzing this solution depositing from it at a given tensiouof an electric current certain metals upon the cathodes, at the same time resaturating the electrolyte constantly by passing it repeatedly through anodes of the same composition, thereby continuously enriching the electrolyte more and more with such netals'as may be present in the anode in comparatively small proportions and which require for deposition an electric current of highertension, and, finally, by the complete deposition of the metals desired to be removed from the electrolyte a concentrated solution of the remaining metals is obtained, from which the latter may be removed by electrical or chemical means.
My invention is particularly applicable in the treatment of copper-nickel ore or matte. and bring the metals coutained therein into solution, i use the matte for anode in an electrolytic bath, in which a solution of a salt of an alkali forms the electrolyte, ordinary carbon or copper-cathodes being employed. By electrolysis I obtain caustic soda at the cathode and. a solution the corresponding salts of the metals of which,
the matte is composed at the anode, while the sulfur contained in the matte remains'as residuum in concentrated form. While I prefer to do so, I do not limit myself to producing the lution may be obtained by chemical or any other process. The metallic solution th usohtained .1 subject to electrolysis in a series of baths, all having matte anodes and cathodes composed, preferably, of copper, the anodes of the baths consistingof disintegrated matte and arranged in such a manner that the metallic solution which forms the electrolyte passes through the'body of the anode and solution in this manner, and the sothrough a suitable diaphragm, past the cathodes, and through an overflow-onto the anode of the bath next in series, and soon through any desired number of baths. The least electropositive metal represented in the electrolyte-in this instance copper-is deposited at the cathodes in the passage of the electrolyie past the cathodes, care being taken that the tension of the electric current does not greatly exceed the electrochemical re-,
quirements for copper, the solvent agent represented in the electrolyte as liberated dissolving a'corresponding quantity of fresh metals from the metaLbe-aring anode of each bath, and by the repeated deposition of copper only and resaturation with the compound metals of the anode the electrolyte becomes more and more saturated with the other metals and impoverished in copper until eventuallyv a point of saturation is reached convenleut for the recovery of the metals other than copper. To remove the last quantities of copper yet contained in the electrolyte, the latter in its passage through thebath last in series is not allowed to pass the cathodes, but is brought to circulate through the anode only and below a diaphragm, permitting only enough of the electrolyte to pass through the diaphragm as will insure complete exhaustion of the copper still contained in the electrolyte at the cathodes. The solution derived from the cathode-section of the bath last in series contains -then only nickel, iron, and cobalt.
The iron is removed from the solution by chemical treatment, and the nickel may be separated from the cobalt by electrolysis orby chemical means.
erous body in the :iccompsuyingdruwings, illustrating sp el-urns for practicing my invention, in the two figures of which like parts are similarly designated, Figure l is a. sectional elevation.
Fizz. 2 is a diugrmn of a, double buttery.
' the invention 1 use the term ore and the term metallifcrous body as including these various substances.
The vessels 1 and 4 at the beginning and end of-the series of electrolytic baths are alike and comprise suits-hie fluid-tight receptacles huving in their bottoms perforated pipesa, carbon or other conductors b, suitably wired to a source of electricity, at mass of the metallifc overlying the carbons and com stituting an anode, a diaphragm d of granular or equivalent permeable material, such as sand, placed upon the anode, a' vertical bridgewell e across one end of the receptacle and extending from its top nearly to its bottom,
an overflow-pipe f at one end, an overflowpipe g opening from the other side of the bridge-wall, and s cathode h, which may be.
composed of a series oi copper or other plates suitable to receive the selected metal or metals to be deposited. Between these two vessels may be arranged on y number of vessels 2 and 3 in all substantial respects like the vesselsl and 4, excepting that they have no bridgewslls end no overflows, hated g.
A water-tank i may be arranged to supply suchas those desigwstcr to the vessel 1, and the tank j may be arranged to supply the exciting fluid to the pipe a of the same vessel. The pipes a, of the succeeding vessels are connected with the outlet of the next preceding vessel by hose or pipes k. The overliow-pipeg of vessel 1 above the diaphragm lends to a tank I, and the pipe g of vessel t leads to s tank m, while the pipe of vessel 4 lends to u. tank n, which is connected with a pump or other forcing device 0, which returns the fluid to any of the vessels, es 2, through pipe p.
The use of a diaphragm may be omitted in such vessels as 2 and 3 if the purity of the copper deposited is not an object.
As an example of one way of carrying out my invention 1 proceed as follows: I supply tank j with common-salt solution of it preferred strength-ssy about 20 permit this solution to flow through pipe a into vessel 1, through the anode c and diaphragm d therein, until the solution reaches the overflows f and y, when thevulve g of overflow g is closed'und the inflow of salt soand pass lotion is diminished and the salt solution ullowed to leave the vessel 1 through overflow into the second vessel in series.
An electric current of the required electroclicmical'tension is then passed through the vessel 1, and the metallic-chlorid solution formed at the anode of vessel 1 passes below. the diaphragm, through overflow f, to the anode of the second vessel, while, a limited quantity of water is allowed to fiow'from tank 6 to the. cathodes of vessel 1 whenever the electrolyte around the luted enough alkali. This elkslinesolu'tion is then withdrawn through overflow g and;
maybe returned to thetankund used over. for further concentration, or it may be withdrawn and otherwise used,'w hile the quantity withdrawn is cohstuntly replenished by a cor-- responding quantity of water hr salt brine from tank i. The metallic-chlorid solution cathodes has accumu from tank 1, passing throughoverfiow f, is
delivered to thonnod'e of vessel 2 and passes. through the anode and diaphragm d oi vescol 2. The electric current is then admitted tovessel 2 at a. tension equivalent to the requirements of the metal to be deposited at the cathode-4n this instance copper-and s quantity of copper equivalent to the electric current is deposited onto the cathodeslofvessel 2, while at the same time .a Quantity of the complex metals of'which the anode is composed is dissolved from the anode and embodied in the electrolyte, so that when the electrolyte leaves vessel 2 by the overflow it contains a larger quantity of metals other than copper than when it entered vessel 2. This operation is repeated successively in' any desired number'of electrolytic baths constructed similarly to vessel 2, and the "electrolyte constantly giving up copper only to the cathodes and dissolving all the time other metals contained in the anode becomes more saturated with those metals in each successive vessel until it has finally reached a, concentration which renders it lit for recovery of the metals other than copper. When the electrolyte has reached this point of concentration, it passes through overflow f to the 'final'vessel 4, of which again there may be any desired number. After the vessel at has been filled to the overflow g the bulk of the electrolyte pussesihrough the anode below .the diaphragm, leaving this vessel 4 through overflow f. The valve 9 in the pipe g being closcd no circulation through the diaphragm in vessel 4 occurs, and thereby the electrolyte above the diaphragm becomes excapacity of the cathodes, so that while the ceases electrolyte coming from the anode and passing through the diaphragm still supplies copper it leaves vessel 4 by overflow g free from dilferent' com position.
copper. So touch of the electrolyte as is not allowed to pass through the diaphragm d leaves vessel 4 through overflow f and enters receptacle n and isretu rned by p u mp 0 or ot her means to vessel 2 or any other of the series in which a like operation is performed. The metallic -chlorid solution leaving vessel 4 through overflow g is then withdrawn from the system and the iron is removed by chemical means, while the nickel, cobalt, and other metals may be separated from each other by ordinary electrolytic orzchemical methods.
Having thus described the application of my process to a specific substance, I wish it understood that I do not limit my'invention to the use of one class of oresonly, but may employ for anodes in a series of baths different kinds of metalliferous bodies-as, for instance, the anodes in vessels 1, 2, and 3 may be composed of copper matte and in vessel 4 the anode may be composed of nickel-bearing iron slag or other metalliferous bodies or the anode in each of the vessels may be of The electrolyte also may dilfer between the individual vessels, and it may be withdrawn from any vessel of the series and returned to the same or any other of the vessels, if sodesired. That part of the electrolyte supplying the cathode of the vessel 4 for the purpose of exhausting the last quantity of copper instead of passing through the diaphragm, as I prefer to do, may
- also be taken from the overflow of vessel 3 and directly conducted to the cathode of ms 581 4.,
If the substance used for anodes contains sulfur, the sulfur is recovered by distillation or other well-known mehods fromv the-residuum of the anode after the metals are extracted and forms a valuable by-product.
Having thusdescribed my invention, what I claim is- 1. The method of separating metals from their ores, which consists in providing an electrolytic bath with a permeable anode com-v posed of the ore bearing the metals to be obtained covered with a diaphragm composed of a granular, permeable substance, and cir-.
selected metal on suitable cathodes and thereby continuously removing such metal and enriching the contents of the solution with the other metals,substantially as described.
3.'The method of recovering copper and separating nickel and cobalt from matte or ore, by electrolysis, which consists in providing a number of electrolytic baths with permeable anodes composed of the material to be treated, electrolyzinn the salt of an alkali in the first of the series of baths and clr'culating the metal-bearing electrolyte thereby obtained successively through the anodes and past the cathodesof the baths next in series, thereby electrodepositing thecopper onto the cathodes of the successive baths and constantly enrichingthe electrolyte with nickel and cobalt, substantially as described.
i. The method of recovering copper and separating nickel and cobalt from matte or ore, by electrolysis, which consists in providiug a number of electrolytic baths with permeable anodes composed of the material to be treated, elect-rolyzing the salt of an alkali in the first of the series of baths and circulating the metal-bearing electrolyte thereby obtained successively through the anodes and past the cathodes of the baths next in series,
thereby electrodepositing the copper onto the cathodes of the successive baths and .constantly enriching the electrolyte with nickel and cobalt, and finally circulating the electrolyte past the cathode only of the succeeding bath, thereby depositing the last traces of copper and separating the remaining solution of nickel and cobalt.
5. In the process-of separating metals from their ores, by electrolysis, circulating an electroly'te capable of dissolving the metals to be separated, between a soluble anode containing the metals to be extracted and a cathode, and through an intervening diaphragm consisting of a granular substance inert to the electric current and chemical action of the electrolyte, and electrolyziug the solution.
5. lo the process of separating metals from their ores, by electrolysis, circulating an electrolyte capable of dissolving the metals successively through the body of a permeable anode bearing the metals to be separated and a'diaphragm consisting of a granular substance inert to the electric current and cbem-' ical action of the electrolyte and past the cathode, and electrolyzing the solution.
7. The method of exhausting an electrolyte composed of the-salts of a number of metals of the individual less-eiectropositive metals contained therein, by circulating the electrolyte through a permeable anode containing the metals represented in the electrolyte, electrolyzing the solution, passing a portion only of the electrolyte thrcugha diapragm to the cathode and entirely precipitating thev metal there from and simultaneously drawing off the remaining electrolyte from the ans-decompartment.
8. The method of exhausting an electrolyte composed of the salts of a number of metals of. the individual less-electropositive metalscontained therein, by circdlating the electrolyte in part through a permeable anode on one-side of a diaphragm and in part past the cathode on the other side ofthe diaphragm, thereby exhausting the electrolyte passing the cathode of the less-positive metals and simultaneously enriching the anode fluid with the metals contained in the anode, substanially as described.
9. The method of separating metals from their ores, which consists in providing an electrolytic bath with a permeable anode co mposed of ore bearing the metals to be obtained and circulating through such anode and through a diaphragm to the cathode an elec trolyte capable of dissolving the-metals, and
simultaneously electrodepositing on suitable cathodes the metals to be separated, keeping the other metals in solution, and finally recovering the sulfur from the residuum of the anode, substantially as described.
In testimony whereof I have hereunto setmy hand this 14th day of September, A. D. 1900.
HANS A. FRASOH.
Witnesses:
WM. H. FINCKEL, O. A. NEALE.
US3015400A 1900-09-15 1900-09-15 Process of recovering and separating metals by electrolysis. Expired - Lifetime US669442A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US3015400A US669442A (en) 1900-09-15 1900-09-15 Process of recovering and separating metals by electrolysis.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US3015400A US669442A (en) 1900-09-15 1900-09-15 Process of recovering and separating metals by electrolysis.

Publications (1)

Publication Number Publication Date
US669442A true US669442A (en) 1901-03-05

Family

ID=2737997

Family Applications (1)

Application Number Title Priority Date Filing Date
US3015400A Expired - Lifetime US669442A (en) 1900-09-15 1900-09-15 Process of recovering and separating metals by electrolysis.

Country Status (1)

Country Link
US (1) US669442A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2624702A (en) * 1949-06-16 1953-01-06 Metallurg De Hoboken Soc Gen Separation of nickel from cobalt containing solutions
US2761829A (en) * 1951-06-29 1956-09-04 Norman H Dolloff Polarization prevention in electrolysis of sulfide ores
US20200277704A1 (en) * 2017-11-24 2020-09-03 Sumitomo Metal Mining Co., Ltd. Method for treating lithium ion battery waste

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2624702A (en) * 1949-06-16 1953-01-06 Metallurg De Hoboken Soc Gen Separation of nickel from cobalt containing solutions
US2761829A (en) * 1951-06-29 1956-09-04 Norman H Dolloff Polarization prevention in electrolysis of sulfide ores
US20200277704A1 (en) * 2017-11-24 2020-09-03 Sumitomo Metal Mining Co., Ltd. Method for treating lithium ion battery waste
US11618959B2 (en) * 2017-11-24 2023-04-04 Sumitomo Metal Mining Co., Ltd. Method for treating lithium ion battery waste

Similar Documents

Publication Publication Date Title
US1980381A (en) Method of making ductile electrolytic iron from sulphide ores
US5569370A (en) Electrochemical system for recovery of metals from their compounds
US669442A (en) Process of recovering and separating metals by electrolysis.
US4312724A (en) Method for the recovery of lead from materials containing lead sulfide
US805969A (en) Separation of metals.
US720235A (en) Process of recovering and separating metals from their ores.
US984703A (en) Process of making sulfuric acid and electrolytic iron.
US2417259A (en) Electrolytic process for preparing manganese and manganese dioxide simultaneously
US2624702A (en) Separation of nickel from cobalt containing solutions
US1007388A (en) Electrolytic method of refining iron.
US1375631A (en) Process of separating and refining metals
US1577422A (en) Refining copper-nickel matte, etc.
US788064A (en) Utilizing spent pickle liquor.
US415576A (en) Werner siemens
US1757047A (en) Process of electrolytically refining copper or copper alloys
US592055A (en) Process of treating ores
US1769605A (en) Process for making electrolytic iron
US669440A (en) Method of recovering metals by electrolysis.
US1928294A (en) Method of refining chromium and chromium alloys
US879633A (en) Process of treating metallic ores or mattes.
US973776A (en) Process of extracting metals from their ores.
US546873A (en) Croft
US2045212A (en) Production of cobalt
US1179522A (en) Process of extracting metals from their ores.
US984090A (en) Treatment of gold-bearing antimony ores.