US2950185A - Production of tantalum powder - Google Patents

Production of tantalum powder Download PDF

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Publication number
US2950185A
US2950185A US741865A US74186558A US2950185A US 2950185 A US2950185 A US 2950185A US 741865 A US741865 A US 741865A US 74186558 A US74186558 A US 74186558A US 2950185 A US2950185 A US 2950185A
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US
United States
Prior art keywords
bath
sodium
potassium
reactor
fluotantalate
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
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US741865A
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English (en)
Inventor
Edward G Hellier
George L Martin
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National Research Corp
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National Research Corp
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Filing date
Publication date
Priority to NL252366D priority Critical patent/NL252366A/xx
Application filed by National Research Corp filed Critical National Research Corp
Priority to US741865A priority patent/US2950185A/en
Priority to DEN16680A priority patent/DE1141794B/de
Priority to FR824092A priority patent/FR1284531A/fr
Application granted granted Critical
Publication of US2950185A publication Critical patent/US2950185A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/16—Making metallic powder or suspensions thereof using chemical processes
    • B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
    • B22F9/24—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
    • 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
    • C22B34/00—Obtaining refractory metals
    • C22B34/20—Obtaining niobium, tantalum or vanadium
    • C22B34/24—Obtaining niobium or tantalum

Definitions

  • This invention relates to the production of tantalum metal in pure powder form.
  • the principal object of the present invention is to provide an improved process for producing tantalum metal which can be converted into usefully ductile material without the necessity of high vacuum sintering operations to remove oxygen.
  • Another object of the invention is to provide an improved method for producing tantalum powder at high production rates :withexcellent control of the reaction to produce uniform, small particles.
  • Still another object of the invention is to provide a process which can be readily controlled to give high production rates in a relatively short time cycle.
  • the invention accordingly comprises the process involving the several steps and the relation and the order of one or more of such steps with respect to each of the others and the products possessing the features, properties and the relation of components which are exemplified in the following detailed disclosure, and the scope of the application 'of which will be indicated in the claims.
  • Fig. 1 is a schematic, diagrammatic illustration of one embodiment of the invention.
  • Fig. 2 is a sectional view of a portion of Fig. 1 taken along the line 2- 2 of Fig. l. i
  • tantalum powder is produced by reducing potassium fluotantalate with sodium.
  • Potassium fluotantalate K TaF has a melting point of about 765 C.
  • a molten bath of the fluotantalate is preferably confined in a reactor maintained at a temperature above the melting point of potassium fluotantalate and liquid sodium is fed to the fused bath of potassium fluotantalate to reduce'the potassium fluotantalate to tantalum powder with the pro-' duction of the byproducts sodium fluoride and potassium fluoride.
  • the byproduct may not uniformly have the ratio of 2 moles of potassium fluoride to 5 moles of sodium fluoride since sodium will reduce potassium fluoride to potassium with the formation of sodium fluoride. Accordingly, the surface of the bath where the sodium is fed may consist largely of sodium fluoride, free sodium and NaK. The NaK thus liberated can reduce the potassium fluotantalate to tantalum metal.
  • Sodium fluoride has a high melting point on the order of 990 C., while potassium fluoride has a relatively lower melting point of about 840 C.
  • a mixture of 5 moles of sodium fluoride and 2 moles of potassium fluoride has a melting point of approximately 875 to 880 :ited States Patented Aug. 23, 1960 C., which is about the boiling point of sodium and con siderably above the boiling point of potassium. It is also'above the boiling point (about 830 C. to 850 C.) of the alloy NaK which can be formed in fairly copious quantities by reaction between sodium and KF.
  • sodium fluoride formed at the surface of the bath by reaction with potassium fluotantalate can remain at the surface and form a concentration in excess of the equilibrium solubility in the available potassium fluotantalate. Accordingly, if the surface is below 990 C., the sodium fluoride can freeze and float as a crust on top of the molten bath of potassium fluotantalate. 'Since sodium is continuously fed to this crust surface, and since this surface is above the boiling point of sodium or the boiling point (about 830 C.-850 C.) of NaK, the sodium and NaK, whichever is present, will continuously remove heat from the frozen surface by vaporizing from this surface.
  • any sodium fluoride formed at the surface which starts to freeze is immediately pulled down into the bath where '(a) it is no longer subjected to the cooling effect of vaporizing sodium and (b) is in the presence of a large excess of potassium fluotantalate for permitting equilibration of the system.
  • Figs. 1 and 2 there is illustrated a very diagrammatic form of one preferred embodiment of the invention.
  • the reactor is indicated at 10 as comprising a cylindrical vessel such as an lnconel pot.
  • the charge of KzTaFq, illustrated at 12 is placed in the pot and the pot is then sealed by an insulated cover 14.
  • the pot is supported in a furnace generally indicated at 16 having a plurality of electrical heating elements 18 therein.
  • Liquid sodium is fed from a sodium supply 20 through pipe 22 onto the surface of the charge 12 of K TaF Individual drops of sodium are illustrated at 24.
  • a reflux condenser 30 is provided in a vent line 28 for refluxing sodium vapors tending to escape through the vent line 28.
  • a vacuum pump 32 is also connected to the vent line to permit evacuation of the interior of the reaction vessel 10.
  • a source of inert gas 34 is also connected to the vent line to permit the introduction of a slight superatmospheric pressure of inert gas into the interior of the reaction vessel.
  • a propeller 40 carried by a propeller shaft 42.
  • This propeller shaft extends through a suitable vacuum-tight gland 44 to a motor schematically indicated at 46.
  • Three baffles 48 are positioned around the interior of the reaction vessel 10. These bafiles serve to discourage circumferential flow of KgTaFq and encourage vertical flow.
  • the combination of the baflles and propellers thus illustrated gives high upward flow of the fused bath at the center of the bath and rapid downward flow at the periphery of the bath. This violent agitation of the bath thus keeps the composition of the bath substantially completely uniform throughout its depth.
  • the propeller will give an upward velocity to the bath of 10 to 20 feet per minute. It will also provide substantially complete recirculation of the bath in 10 or 15 seconds.
  • Example I One hundred pounds of KzTaFq is placed in an Inconel reactor 12 inches in diameter and 12 inches high.
  • the inside of the reactor is provided with 3 baffles having radial dimensions of about 1 inch as illustrated in Fig. 1 and is provided with a propeller of inches in diameter with a pitch of 35 During the reduction stage of the operation the propeller is run at 175 r.p.m.
  • the reactor is sealed, and repeatedly evacuated and back filled with argon to provide a slight positive pressure of a few rni'llimeters above atmosphere. During this repeated evacuation and back filling with argon, the reactor is heated to 200 to 400 C. to assure removal of all water vapor and other gases or vapors. The reactor is then heated to 925 C.
  • the product consisted of tantalum powder having the following particle size distribution after being run through a Wiley mill:
  • the improvement whidh comprises confining a bath of molten potassium fluotantalate in a reactor at a temperature above 900 C., feeding molten sodium to the surface of the bath at a rate in excess of one pound per square foot per hour of bath surface, refluxing to said surface sodium and NaK evaporating from said surface, and agitating said bath with a mechanical agitator at a suificiently high rate and with substantially lineal upward and downward flow to draw into the bath any sodium fluoride crystals floating on the surface of the bath.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacture And Refinement Of Metals (AREA)
US741865A 1958-06-13 1958-06-13 Production of tantalum powder Expired - Lifetime US2950185A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
NL252366D NL252366A (fr) 1958-06-13
US741865A US2950185A (en) 1958-06-13 1958-06-13 Production of tantalum powder
DEN16680A DE1141794B (de) 1958-06-13 1959-05-06 Verfahren zur Herstellung von Tantalpulver
FR824092A FR1284531A (fr) 1958-06-13 1960-04-11 Procédé de fabrication de tantale métallique

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US741865A US2950185A (en) 1958-06-13 1958-06-13 Production of tantalum powder
FR824092A FR1284531A (fr) 1958-06-13 1960-04-11 Procédé de fabrication de tantale métallique

Publications (1)

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US2950185A true US2950185A (en) 1960-08-23

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US741865A Expired - Lifetime US2950185A (en) 1958-06-13 1958-06-13 Production of tantalum powder

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US (1) US2950185A (fr)
DE (1) DE1141794B (fr)
FR (1) FR1284531A (fr)
NL (1) NL252366A (fr)

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3295951A (en) * 1965-02-02 1967-01-03 Nat Res Corp Production of metals
US3992192A (en) * 1974-07-01 1976-11-16 Haig Vartanian Metal powder production
US4141720A (en) * 1978-05-16 1979-02-27 Nrc, Inc. Tantalum powder reclaiming
US4149876A (en) * 1978-06-06 1979-04-17 Fansteel Inc. Process for producing tantalum and columbium powder
US4445931A (en) * 1980-10-24 1984-05-01 The United States Of America As Represented By The Secretary Of The Interior Production of metal powder
US5442978A (en) * 1994-05-19 1995-08-22 H. C. Starck, Inc. Tantalum production via a reduction of K2TAF7, with diluent salt, with reducing agent provided in a fast series of slug additions
US5524836A (en) * 1993-02-12 1996-06-11 Board Of Control Of Michigan Technological University Method for producing powder from polycrystalline inorganic material
WO2000031310A1 (fr) 1998-11-25 2000-06-02 Cabot Corporation Tantale de grande purete et produits le contenant, tels que les cibles pulverisees
US20030082864A1 (en) * 1998-05-27 2003-05-01 Harry Rosenberg Tantalum sputtering target and method of manufacture
US20040008472A1 (en) * 1999-02-08 2004-01-15 Tripp Terrance B. Capacitor substrates made of refractory metal nitrides
US20040163491A1 (en) * 2000-10-10 2004-08-26 Shekhter Leonid N. Metalothermic reduction of refractory metal oxides
US6863750B2 (en) 2000-05-22 2005-03-08 Cabot Corporation High purity niobium and products containing the same, and methods of making the same
US20050279187A1 (en) * 2004-06-21 2005-12-22 Shekhter Leonid N Metalothermic reduction of refractory metal oxides
US20060065073A1 (en) * 2004-09-29 2006-03-30 Shekhter Leonid N Magnesium removal from magnesium reduced metal powders
US20060213327A1 (en) * 2005-03-22 2006-09-28 Shekhter Leonid N Method of preparing primary refractory metal
US20060230877A1 (en) * 2000-02-08 2006-10-19 Yukio Oda Nitrogen-containing metal powder, production process thereof, and porous sintered body and solid electrolytic capacitor using the metal powder
US20080011124A1 (en) * 2004-09-08 2008-01-17 H.C. Starck Gmbh & Co. Kg Deoxidation of Valve Metal Powders
US20080105082A1 (en) * 2004-09-29 2008-05-08 Shekhter Leonid N Magnesium Removal From Magnesium Reduced Metal Powders
US7485198B2 (en) 2001-01-11 2009-02-03 Cabot Corporation Tantalum and niobium billets and methods of producing the same
EP2055412A2 (fr) 1998-05-06 2009-05-06 H.C. Starck GmbH Poudres de métal produites par la réduction des oxydes avec un magnésium gazeux
CN101879605A (zh) * 2010-06-18 2010-11-10 江门富祥电子材料有限公司 搅拌钠还原氟钽酸钾制取钽粉的方法及装置
CN101879603A (zh) * 2010-06-18 2010-11-10 江门富祥电子材料有限公司 钽粉的生产方法和装置
CN104801725A (zh) * 2015-05-18 2015-07-29 江门富祥电子材料有限公司 一种钠还原氟钽酸钾的反应装置及用其制造钽粉的方法
WO2019173087A1 (fr) 2018-03-05 2019-09-12 Global Advanced Metals Usa, Inc. Anodes contenant une poudre sphérique et des condensateurs
WO2020027874A2 (fr) 2018-03-05 2020-02-06 Global Advanced Metals Usa, Inc. Poudre de tantale sphérique, produits la contenant, et ses procédés de production

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4684399A (en) * 1986-03-04 1987-08-04 Cabot Corporation Tantalum powder process
DE3712281A1 (de) * 1987-04-10 1988-10-27 Heraeus Gmbh W C Verfahren zur herstellung von hochduktilem tantal-halbzeug

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2069705A (en) * 1934-04-30 1937-02-02 Alais & Froges & Camarque Cie Process of manufacture of metallic glucinum and its alloys
US2193364A (en) * 1936-06-06 1940-03-12 Perosa Corp Process for obtaining beryllium and beryllium alloys
CA541517A (fr) * 1957-05-28 Fansteel Metallurgical Corporation Recuperation de tantale et columbium
US2823991A (en) * 1954-06-23 1958-02-18 Nat Distillers Chem Corp Process for the manufacture of titanium metal
GB791121A (en) * 1954-11-18 1958-02-26 Atomic Energy Authority Uk Improvements in or relating to the production of niobium
US2837426A (en) * 1955-01-31 1958-06-03 Nat Distillers Chem Corp Cyclic process for the manufacture of titanium-aluminum alloys and regeneration of intermediates thereof

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE815107C (de) * 1950-01-17 1951-09-27 Hermann C Starck A G Verfahren zur Herstellung von Tantal-Metall

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA541517A (fr) * 1957-05-28 Fansteel Metallurgical Corporation Recuperation de tantale et columbium
US2069705A (en) * 1934-04-30 1937-02-02 Alais & Froges & Camarque Cie Process of manufacture of metallic glucinum and its alloys
US2193364A (en) * 1936-06-06 1940-03-12 Perosa Corp Process for obtaining beryllium and beryllium alloys
US2823991A (en) * 1954-06-23 1958-02-18 Nat Distillers Chem Corp Process for the manufacture of titanium metal
GB791121A (en) * 1954-11-18 1958-02-26 Atomic Energy Authority Uk Improvements in or relating to the production of niobium
US2837426A (en) * 1955-01-31 1958-06-03 Nat Distillers Chem Corp Cyclic process for the manufacture of titanium-aluminum alloys and regeneration of intermediates thereof

Cited By (50)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3295951A (en) * 1965-02-02 1967-01-03 Nat Res Corp Production of metals
US3992192A (en) * 1974-07-01 1976-11-16 Haig Vartanian Metal powder production
US4141720A (en) * 1978-05-16 1979-02-27 Nrc, Inc. Tantalum powder reclaiming
US4149876A (en) * 1978-06-06 1979-04-17 Fansteel Inc. Process for producing tantalum and columbium powder
US4445931A (en) * 1980-10-24 1984-05-01 The United States Of America As Represented By The Secretary Of The Interior Production of metal powder
US5524836A (en) * 1993-02-12 1996-06-11 Board Of Control Of Michigan Technological University Method for producing powder from polycrystalline inorganic material
WO1995032313A1 (fr) * 1994-05-19 1995-11-30 H.C. Starck, Inc. Production de tantale et tantale ainsi produit
US5442978A (en) * 1994-05-19 1995-08-22 H. C. Starck, Inc. Tantalum production via a reduction of K2TAF7, with diluent salt, with reducing agent provided in a fast series of slug additions
EP2055412A2 (fr) 1998-05-06 2009-05-06 H.C. Starck GmbH Poudres de métal produites par la réduction des oxydes avec un magnésium gazeux
US6958257B2 (en) 1998-05-27 2005-10-25 Honeywell International Inc. Tantalum sputtering target and method of manufacture
US20050284546A1 (en) * 1998-05-27 2005-12-29 Harry Rosenberg Tantalum sputtering target and method of manufacture
US20030082864A1 (en) * 1998-05-27 2003-05-01 Harry Rosenberg Tantalum sputtering target and method of manufacture
WO2000031310A1 (fr) 1998-11-25 2000-06-02 Cabot Corporation Tantale de grande purete et produits le contenant, tels que les cibles pulverisees
US7585380B2 (en) 1998-11-25 2009-09-08 Cabot Corporation High purity tantalum, products containing the same, and methods of making the same
US20030168131A1 (en) * 1998-11-25 2003-09-11 Michaluk Christopher A. High purity tantalum, products containing the same, and methods of making the same
US7431782B2 (en) 1998-11-25 2008-10-07 Cabot Corporation High purity tantalum, products containing the same, and methods of making the same
US6893513B2 (en) 1998-11-25 2005-05-17 Cabot Corporation High purity tantalum, products containing the same, and methods of making the same
US6348113B1 (en) 1998-11-25 2002-02-19 Cabot Corporation High purity tantalum, products containing the same, and methods of making the same
US20040008472A1 (en) * 1999-02-08 2004-01-15 Tripp Terrance B. Capacitor substrates made of refractory metal nitrides
US6927967B2 (en) 1999-02-08 2005-08-09 H. C. Starck Inc. Capacitor substrates made of refractory metal nitrides
US20060230877A1 (en) * 2000-02-08 2006-10-19 Yukio Oda Nitrogen-containing metal powder, production process thereof, and porous sintered body and solid electrolytic capacitor using the metal powder
US7473294B2 (en) 2000-02-08 2009-01-06 Cabot Supermetals K.K. Nitrogen-containing metal powder, production process thereof, and porous sintered body and solid electrolytic capacitor using the metal powder
US6863750B2 (en) 2000-05-22 2005-03-08 Cabot Corporation High purity niobium and products containing the same, and methods of making the same
US20050263217A1 (en) * 2000-05-22 2005-12-01 Cabot Corporation High purity niobium and products containing the same, and methods of making the same
US20070107549A1 (en) * 2000-10-10 2007-05-17 Shekhter Leonid N Metalothermic reduction of refractory metal oxides
US7678175B2 (en) 2000-10-10 2010-03-16 H.C. Starck Inc. Metalothermic reduction of refractory metal oxides
US20040163491A1 (en) * 2000-10-10 2004-08-26 Shekhter Leonid N. Metalothermic reduction of refractory metal oxides
US7150776B2 (en) 2000-10-10 2006-12-19 H.C. Starck Inc. Metalothermic reduction of refractory metal oxides
US6849104B2 (en) 2000-10-10 2005-02-01 H. C. Starck Inc. Metalothermic reduction of refractory metal oxides
US20090068434A1 (en) * 2001-01-11 2009-03-12 Cabot Corporation Tantalum and Niobium Billets and Methods of Producing the Same
US8231744B2 (en) 2001-01-11 2012-07-31 Global Advanced Metals, Usa, Inc. Tantalum and niobium billets and methods of producing the same
US7485198B2 (en) 2001-01-11 2009-02-03 Cabot Corporation Tantalum and niobium billets and methods of producing the same
US7354472B2 (en) 2004-06-21 2008-04-08 H.C. Starck Inc. Metalothermic reduction of refractory metal oxides
US20050279187A1 (en) * 2004-06-21 2005-12-22 Shekhter Leonid N Metalothermic reduction of refractory metal oxides
US20080011124A1 (en) * 2004-09-08 2008-01-17 H.C. Starck Gmbh & Co. Kg Deoxidation of Valve Metal Powders
US7431751B2 (en) 2004-09-29 2008-10-07 H.C. Starck Inc. Magnesium removal from magnesium reduced metal powders
US20080105082A1 (en) * 2004-09-29 2008-05-08 Shekhter Leonid N Magnesium Removal From Magnesium Reduced Metal Powders
US20060065073A1 (en) * 2004-09-29 2006-03-30 Shekhter Leonid N Magnesium removal from magnesium reduced metal powders
US20060213327A1 (en) * 2005-03-22 2006-09-28 Shekhter Leonid N Method of preparing primary refractory metal
US7399335B2 (en) 2005-03-22 2008-07-15 H.C. Starck Inc. Method of preparing primary refractory metal
CN101879605A (zh) * 2010-06-18 2010-11-10 江门富祥电子材料有限公司 搅拌钠还原氟钽酸钾制取钽粉的方法及装置
CN101879603B (zh) * 2010-06-18 2012-05-30 江门富祥电子材料有限公司 钽粉的生产方法和装置
CN101879603A (zh) * 2010-06-18 2010-11-10 江门富祥电子材料有限公司 钽粉的生产方法和装置
CN104801725A (zh) * 2015-05-18 2015-07-29 江门富祥电子材料有限公司 一种钠还原氟钽酸钾的反应装置及用其制造钽粉的方法
CN104801725B (zh) * 2015-05-18 2018-01-23 江门富祥电子材料有限公司 一种钠还原氟钽酸钾的反应装置及用其制造钽粉的方法
WO2019173087A1 (fr) 2018-03-05 2019-09-12 Global Advanced Metals Usa, Inc. Anodes contenant une poudre sphérique et des condensateurs
WO2020027874A2 (fr) 2018-03-05 2020-02-06 Global Advanced Metals Usa, Inc. Poudre de tantale sphérique, produits la contenant, et ses procédés de production
US10943744B2 (en) 2018-03-05 2021-03-09 Global Advanced Metals Usa, Inc. Anodes containing spherical powder and capacitors
US11508529B2 (en) 2018-03-05 2022-11-22 Global Advanced Metals Usa, Inc. Anodes containing spherical powder and capacitors
US11691197B2 (en) 2018-03-05 2023-07-04 Global Advanced Metals Usa, Inc. Spherical tantalum powder, products containing the same, and methods of making the same

Also Published As

Publication number Publication date
DE1141794B (de) 1962-12-27
DE1141794C2 (fr) 1963-06-27
FR1284531A (fr) 1962-02-16
NL252366A (fr)

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