AU2021384253A1 - Reduction method and system for high-melting-point metal oxide, using fluoride-based electrolytes - Google Patents
Reduction method and system for high-melting-point metal oxide, using fluoride-based electrolytes Download PDFInfo
- Publication number
- AU2021384253A1 AU2021384253A1 AU2021384253A AU2021384253A AU2021384253A1 AU 2021384253 A1 AU2021384253 A1 AU 2021384253A1 AU 2021384253 A AU2021384253 A AU 2021384253A AU 2021384253 A AU2021384253 A AU 2021384253A AU 2021384253 A1 AU2021384253 A1 AU 2021384253A1
- Authority
- AU
- Australia
- Prior art keywords
- metal
- alloy
- metal oxide
- fluoride
- eutectic composition
- 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.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 157
- 229910044991 metal oxide Inorganic materials 0.000 title claims abstract description 76
- 150000004706 metal oxides Chemical class 0.000 title claims abstract description 76
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 title claims description 54
- 230000009467 reduction Effects 0.000 title abstract description 19
- 239000003792 electrolyte Substances 0.000 title description 2
- 229910052751 metal Inorganic materials 0.000 claims description 215
- 239000002184 metal Substances 0.000 claims description 215
- 230000008569 process Effects 0.000 claims description 84
- 230000004907 flux Effects 0.000 claims description 76
- 229910045601 alloy Inorganic materials 0.000 claims description 72
- 239000000956 alloy Substances 0.000 claims description 72
- 230000005496 eutectics Effects 0.000 claims description 71
- 239000000203 mixture Substances 0.000 claims description 57
- 229910001338 liquidmetal Inorganic materials 0.000 claims description 41
- 150000003839 salts Chemical class 0.000 claims description 40
- 229910001092 metal group alloy Inorganic materials 0.000 claims description 30
- 239000002893 slag Substances 0.000 claims description 26
- 239000001301 oxygen Substances 0.000 claims description 20
- 229910052760 oxygen Inorganic materials 0.000 claims description 20
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 19
- 239000006227 byproduct Substances 0.000 claims description 18
- 239000000654 additive Substances 0.000 claims description 15
- 230000000996 additive effect Effects 0.000 claims description 13
- 239000003638 chemical reducing agent Substances 0.000 claims description 11
- WUKWITHWXAAZEY-UHFFFAOYSA-L calcium difluoride Chemical compound [F-].[F-].[Ca+2] WUKWITHWXAAZEY-UHFFFAOYSA-L 0.000 claims description 10
- 229910001634 calcium fluoride Inorganic materials 0.000 claims description 10
- 229910052759 nickel Inorganic materials 0.000 claims description 8
- 229910052725 zinc Inorganic materials 0.000 claims description 8
- 229910052719 titanium Inorganic materials 0.000 claims description 7
- 229910052726 zirconium Inorganic materials 0.000 claims description 7
- 239000011777 magnesium Substances 0.000 claims description 6
- 229910052718 tin Inorganic materials 0.000 claims description 6
- 229910052804 chromium Inorganic materials 0.000 claims description 5
- 229910052742 iron Inorganic materials 0.000 claims description 5
- 229910052748 manganese Inorganic materials 0.000 claims description 5
- 229910052721 tungsten Inorganic materials 0.000 claims description 5
- 229910052749 magnesium Inorganic materials 0.000 claims description 4
- 229910052695 Americium Inorganic materials 0.000 claims description 3
- 229910052684 Cerium Inorganic materials 0.000 claims description 3
- 229910052685 Curium Inorganic materials 0.000 claims description 3
- 229910052692 Dysprosium Inorganic materials 0.000 claims description 3
- 229910052691 Erbium Inorganic materials 0.000 claims description 3
- 229910052693 Europium Inorganic materials 0.000 claims description 3
- 229910052688 Gadolinium Inorganic materials 0.000 claims description 3
- 229910052689 Holmium Inorganic materials 0.000 claims description 3
- 229910052764 Mendelevium Inorganic materials 0.000 claims description 3
- 229910052779 Neodymium Inorganic materials 0.000 claims description 3
- 229910052781 Neptunium Inorganic materials 0.000 claims description 3
- 229910052778 Plutonium Inorganic materials 0.000 claims description 3
- 229910052777 Praseodymium Inorganic materials 0.000 claims description 3
- 229910052774 Proactinium Inorganic materials 0.000 claims description 3
- 229910052772 Samarium Inorganic materials 0.000 claims description 3
- 229910052771 Terbium Inorganic materials 0.000 claims description 3
- 229910052776 Thorium Inorganic materials 0.000 claims description 3
- 229910052775 Thulium Inorganic materials 0.000 claims description 3
- 229910052770 Uranium Inorganic materials 0.000 claims description 3
- 229910052769 Ytterbium Inorganic materials 0.000 claims description 3
- 229910052767 actinium Inorganic materials 0.000 claims description 3
- 229910001632 barium fluoride Inorganic materials 0.000 claims description 3
- 229910052791 calcium Inorganic materials 0.000 claims description 3
- 239000011575 calcium Substances 0.000 claims description 3
- 229910052802 copper Inorganic materials 0.000 claims description 3
- 229910052735 hafnium Inorganic materials 0.000 claims description 3
- 229910052745 lead Inorganic materials 0.000 claims description 3
- 229910001635 magnesium fluoride Inorganic materials 0.000 claims description 3
- 229910052758 niobium Inorganic materials 0.000 claims description 3
- 229910001637 strontium fluoride Inorganic materials 0.000 claims description 3
- FVRNDBHWWSPNOM-UHFFFAOYSA-L strontium fluoride Chemical compound [F-].[F-].[Sr+2] FVRNDBHWWSPNOM-UHFFFAOYSA-L 0.000 claims description 3
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 2
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 claims description 2
- 239000002994 raw material Substances 0.000 abstract description 8
- 239000011261 inert gas Substances 0.000 abstract description 7
- 238000004519 manufacturing process Methods 0.000 abstract description 7
- 229910002065 alloy metal Inorganic materials 0.000 abstract description 5
- 239000010936 titanium Substances 0.000 description 18
- 238000006243 chemical reaction Methods 0.000 description 15
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 12
- 238000002844 melting Methods 0.000 description 8
- 230000008018 melting Effects 0.000 description 7
- 230000008901 benefit Effects 0.000 description 6
- 238000001816 cooling Methods 0.000 description 6
- 239000007788 liquid Substances 0.000 description 6
- 238000007670 refining Methods 0.000 description 6
- KZBUYRJDOAKODT-UHFFFAOYSA-N Chlorine Chemical compound ClCl KZBUYRJDOAKODT-UHFFFAOYSA-N 0.000 description 5
- 238000005260 corrosion Methods 0.000 description 5
- 230000007797 corrosion Effects 0.000 description 5
- 230000007613 environmental effect Effects 0.000 description 5
- 239000012467 final product Substances 0.000 description 5
- 239000000843 powder Substances 0.000 description 5
- 238000011084 recovery Methods 0.000 description 5
- 229910002971 CaTiO3 Inorganic materials 0.000 description 4
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L Magnesium chloride Chemical compound [Mg+2].[Cl-].[Cl-] TWRXJAOTZQYOKJ-UHFFFAOYSA-L 0.000 description 4
- 229910010413 TiO 2 Inorganic materials 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- 238000002203 pretreatment Methods 0.000 description 4
- 238000011946 reduction process Methods 0.000 description 4
- 238000000926 separation method Methods 0.000 description 4
- 239000002131 composite material Substances 0.000 description 3
- 238000004821 distillation Methods 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 229910000765 intermetallic Inorganic materials 0.000 description 3
- 150000002739 metals Chemical class 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 2
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 229910052783 alkali metal Inorganic materials 0.000 description 2
- 150000001340 alkali metals Chemical class 0.000 description 2
- 150000001342 alkaline earth metals Chemical class 0.000 description 2
- 239000001110 calcium chloride Substances 0.000 description 2
- 229910001628 calcium chloride Inorganic materials 0.000 description 2
- 235000011148 calcium chloride Nutrition 0.000 description 2
- 239000007795 chemical reaction product Substances 0.000 description 2
- 239000000460 chlorine Substances 0.000 description 2
- 229910052801 chlorine Inorganic materials 0.000 description 2
- 238000011109 contamination Methods 0.000 description 2
- 238000010924 continuous production Methods 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 229910001629 magnesium chloride Inorganic materials 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910001510 metal chloride Inorganic materials 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 238000010079 rubber tapping Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 238000007711 solidification Methods 0.000 description 2
- 230000008023 solidification Effects 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- 231100000331 toxic Toxicity 0.000 description 2
- 230000002588 toxic effect Effects 0.000 description 2
- 229910014813 CaC2 Inorganic materials 0.000 description 1
- 229910004140 HfO Inorganic materials 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- 229910017676 MgTiO3 Inorganic materials 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 229910052784 alkaline earth metal Inorganic materials 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000005868 electrolysis reaction Methods 0.000 description 1
- 150000002222 fluorine compounds Chemical class 0.000 description 1
- 150000004820 halides Chemical class 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000012805 post-processing Methods 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- XJDNKRIXUMDJCW-UHFFFAOYSA-J titanium tetrachloride Chemical compound Cl[Ti](Cl)(Cl)Cl XJDNKRIXUMDJCW-UHFFFAOYSA-J 0.000 description 1
- 239000002341 toxic gas Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- DUNKXUFBGCUVQW-UHFFFAOYSA-J zirconium tetrachloride Chemical compound Cl[Zr](Cl)(Cl)Cl DUNKXUFBGCUVQW-UHFFFAOYSA-J 0.000 description 1
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
- C22B34/00—Obtaining refractory metals
- C22B34/10—Obtaining titanium, zirconium or hafnium
- C22B34/12—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08
- C22B34/1263—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08 obtaining metallic titanium from titanium compounds, e.g. by reduction
- C22B34/1268—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08 obtaining metallic titanium from titanium compounds, e.g. by reduction using alkali or alkaline-earth metals or amalgams
-
- 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
- C22B34/10—Obtaining titanium, zirconium or hafnium
- C22B34/12—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08
- C22B34/1263—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08 obtaining metallic titanium from titanium compounds, e.g. by reduction
- C22B34/1277—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08 obtaining metallic titanium from titanium compounds, e.g. by reduction using other metals, e.g. Al, Si, Mn
-
- 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
- C22B5/00—General methods of reducing to metals
- C22B5/02—Dry methods smelting of sulfides or formation of mattes
- C22B5/04—Dry methods smelting of sulfides or formation of mattes by aluminium, other metals or silicon
-
- 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
- C22B9/00—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
- C22B9/10—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals with refining or fluxing agents; Use of materials therefor, e.g. slagging or scorifying agents
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
- C25C3/26—Electrolytic production, recovery or refining of metals by electrolysis of melts of titanium, zirconium, hafnium, tantalum or vanadium
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
- C25C3/26—Electrolytic production, recovery or refining of metals by electrolysis of melts of titanium, zirconium, hafnium, tantalum or vanadium
- C25C3/28—Electrolytic production, recovery or refining of metals by electrolysis of melts of titanium, zirconium, hafnium, tantalum or vanadium of titanium
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
- C25C3/30—Electrolytic production, recovery or refining of metals by electrolysis of melts of manganese
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
- C25C3/34—Electrolytic production, recovery or refining of metals by electrolysis of melts of metals not provided for in groups C25C3/02 - C25C3/32
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
- C25C3/36—Alloys obtained by cathodic reduction of all their ions
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C7/00—Constructional parts, or assemblies thereof, of cells; Servicing or operating of cells
- C25C7/005—Constructional parts, or assemblies thereof, of cells; Servicing or operating of cells of cells for the electrolysis of melts
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C7/00—Constructional parts, or assemblies thereof, of cells; Servicing or operating of cells
- C25C7/06—Operating or servicing
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Mechanical Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Electrolytic Production Of Metals (AREA)
- Manufacture And Refinement Of Metals (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
Abstract
The present invention relates to a metal oxide reduction method and, specifically, to a metal oxide reduction method which, in producing a high-grade alloy metal using a metal oxide as a raw material, enables operation in the atmosphere by moving away from an existing production process in an inert gas atmosphere, and is easy to commercialize and can maximize efficiency, as an eco-friendly method is used.
Description
='~~~ici~2022/10800"7~.1111111liiiIIIIIIliiiIIIIIIIII111111IIliiiliiiIIIIliiiIIIIliii SESQ5KSLSTSVSYTHTJTMTNTRTTTZ, UAUGUSUZVCVNWSZAZMZW. r~ JJ~Al HAt- ~-II o1-r l94 ii]~tiu4s iftt~-~9t}-OA):ARIPO(BWGElGMRE, LRLSMWMZNARWSDSLSTSZTZUGZM, ZW),0 BYKG~RUTJTM) 01-fl ci(ALATBEBGCHCYCZDEDKEEESFL, FRGBGRHRHUlIEISITLTLULVMCMX MTNLNOPLPTRORSSESI,5KSMTR),OAPL (BFBJCFCGCLCMGAGNGQGWEMML MRNESNTDTG). 231 0711: (2Q0 21~
[Invention Title]
[Technical field]
The present disclosure relates to a reduction method for a high-melting-point metal oxide,
and specifically, to a reduction method and system for a metal oxide in which an operation is
enabled in an atmosphere without using an existing production process in an inert gas atmosphere
and the efficiency thereof can be maximized and the easy commercialization thereof is provided
using an eco-friendly method..
[Background Art]
When a metal typically known in the art is referred to as any metal "M", the metal M may
be obtained by reducing a raw material such as an oxide or halide. Among the methods for
producing the desired metal M, the relatively well-known and most widely used method in the art
is a so-called Kroll process.
Typically, the Kroll process may be summarized as a process in which molten magnesium
is used as a reducing agent and a chloride of the desired metal M, such as titanium chloride or
zirconium chloride, is input thereto to reduce titanium or zirconium. In this regard, more details
of the Kroll process may be found in US Registration Patent No. 5,035,404.
Since this Kroll process is a process using chloride as a raw material, chlorine gas and
magnesium chloride are produced as by-products during the process. Among these by-products,
the chlorine gas is regarded as a representative matter of the Kroll process as an environmental
matter that causes fatal matters to the a human body, and in the case of magnesium chloride, it causes a matter in the process of quickly corroding a reaction vessel, which is called an cell, a melting furnace, or a crucible.
As such, the Kroll process requires an additional device to resolve environmentally
acceptable regulations, and is accompanied by frequent replacement of the reaction vessel,
resulting in high cost for operating the process.
On the other hand, in the Kroll process, the obtained metal is produced in the form of a
sponge including a large number of pores, so that it is very difficult to control oxygen that may
present in the metal. In other words, the Kroll process has limitations in obtaining high-purity
metals.
An electrolytic refining process is being researched to replace these existing processes,
the process has the advantage of being simpler than an existing process without generating chlorine
gas by directly reducing the metal oxide, but has a matter in that the form of recovered metal is
limited to powder and a particle size of the powder is also limited, making it difficult to control an
oxygen concentration in the metal after the process. In order to overcome this, although the
specific surface area of the recovered metal must be lowered by producing an ingot using a process
such as vacuum arc melting while the recovered metal powder produced by a refining process is
not exposed to the atmosphere, in this case, large-scale industrial facilities are difficult and realistic
difficulties are present in terms of cost.
On the other hand, the present inventors proposed that, a liquid copper-aided electrolysis
(LCE) process (see Patent Documents 1 to 3) to solve the matters of the preceding process involves
a method of producing a target metal as an alloy through an electrolytic reduction process using a
reducing agent, and then refining a high-purity target metal through electrolytic refining.
However, even in this electrolytic reduction process, a chlorine-based flux with a high volatilization rate is used, causing rapid corrosion of equipment and matters in terms of cost, and generation of chlorine gas, which requires operation in a closed system in an argon gas atmosphere.
[Disclosure]
[Technical Problem]
[Patent Documents]
(Patent Document 1) US Registration Patent No. 5,035,404
(Patent Document 2) Korean Patent Registration No. 10-1757626
(Patent Document 3) Korean Patent Registration No. 10-1793471
(Patent Document 4) Korean Patent Registration No. 10-1878652
[Non-Patent Document]
(Non-Patent Document 1) Antoine Allanore, Journal of The Electrochemical Society, 162
(1) (2015) E13-E22
The present disclosure has been proposed to solve the matters of the prior art as described
above, and the present disclosure is for the purposed of reducing a high-melting point metal oxide
in an environmentally friendly and highly-efficient atmospheric environment using a fluoride
based flux to produce a high-grade alloy metal. The present disclosure is for the purpose of
providing a method and system for doing so.
The present disclosure is characterized by producing a liquid metal alloy of metal M, and
metal M 2 forming an eutectic phase with each other. Since a melting point of metal M, is lowered
by a eutectic reaction, reduction may be effectively performed at a relatively low temperature,
which may significantly save energy and lead to cost reduction. In addition, the present
disclosure is obtained in a liquid alloy state (liquid metal alloy of M, and M 2 ) by the eutectic
reaction, so that the metal alloy itself may be used as a final product. In addition, the metal M' may be obtained by electrorefining of the obtained metal alloy. The liquid alloy thus obtained may be thoroughly separated from an environment in which oxygen may present, and thus contamination by oxygen may be significantly prevented. That is, it is possible to obtain a high purity metal alloy and metal M' according to the above aspects.
The present disclosure is directed to providing an alloy metal reduction method that may
increase a high-grade production rate of final products compared to the related art and has high
energy efficiency and is advantageous for commercialization.
[Technical Solution]
According to the present disclosure, a method of reducing metal M, from a metal oxide is
provided.
According to the present disclosure, the method of reducing the metal M, from the metal
oxide includes:
forming a molten salt of a fluoride-based flux in an cell;
putting, into the cell, a metal M 2 forming an eutectic phase with the metal M1 , and a
reducing agent including a metal M 3 to produce an eutectic composition of the metal M 2 and the
metal M3 ; and
reducing the metal M' by reacting the metal oxide with the eutectic composition and
forming a liquid metal alloy with the reduced metal M' and M 2 .
In the method of reducing the metal M' from the metal oxide, the molten salt of the
fluoride-based flux may be smaller than a density of the eutectic composition of the metal M 2 and
the metal M 3 and the metal oxide.
According to the present disclosure, a molten salt of the fluoride-based flux has a
volatilization rate of 10% by weight or less, specifically 5% by weight or less, and more specifically 2% by weight or less for 10 hours at 1,600 °C.
According to the present disclosure, the fluoride-based flux may be one or more selected
from the group consisting of MgF2, CaF2, SrF2, and BaF2, and specifically may be CaF2.
According to the present disclosure, the metal M' may be one or more selected from the
group consisting of Ti, Zr, Hf, W, Fe, Ni, Zn, Co, Mn, Cr, Ta, Ga, Nb, Sn, Ag, La, Ce, Pr, Nd, Pm,
Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Ac, Th, Pa, U, Np, Pu, Am, Cm, Bk, Cf, Es, Fm, Md, and
No.
According to the present disclosure, the metal M 2 may be one or more selected from the
group consisting of Cu, Ni, Sn, Zn, Pb, Bi, Cd, and alloys thereof, and specifically may be Cu.
According to the present disclosure, the metal M3 may be one or more selected from the
group consisting of Ca, Mg, Al, and alloys thereof, and specifically may be Mg.
According to the present disclosure, the metal oxide may include one or more selected
from the group consisting of MxOz and MIxM 3 yOz, where x and y are real numbers of 1 to 3,
respectively, and z is a real number of 1 to 4.
According to the present disclosure, a process of reducing the metal M, by reacting the
metal oxide with the eutectic composition may be performed in air or in fluoride.
According to the present disclosure, a process of reducing the metal M, by reacting the
metal oxide with the eutectic composition may be performed in a range of 900 to 1,600 °C
According to the present disclosure, a method of reducing the metal M, from the metal
oxide may further include forming slags of the molten salt and a by-product generated in a process
of reducing the metal M' by reacting the metal oxide with the eutectic composition by adding a
slag-forming additive, and specifically the slag-forming additive may include one or more selected
from the group consisting of MgO, CaO, FeO, BaO, Si0 2 , and A1 2 0 3 .
According to the present disclosure, the method includes: forming a layer in which the
liquid metal alloy is positioned at a bottom of the cell and separated from the eutectic composition,
and continuously obtaining the liquid metal alloy through a lower portion of the cell; and
forming a distinct layer on top of the eutectic composition using the slag, and continuously
removing the slag through a top of the cell.
According to the present disclosure, the method may further include electrorefining the
liquid metal alloy to produce the metal M1 . A metal alloy or metal according to the present disclosure may be one obtained by any
method disclosed herein or a combination thereof, and may be a metal alloy having a residual
content of 0.1% by weight or less, specifically 0.01% by weight or less, and more specifically
0.001% by weight or less, and an oxygen content of 1,800 ppm or less, specifically 1,500 ppm or
less, and more specifically 1,200 ppm or less.
A system for reducing metal M' from a metal oxide according to the present disclosure
may include:
an cell;
a molten salt of a fluoride-based flux positioned in the cell;
a eutectic composition of metal M 2 and metal M 3 positioned at a lower portion of the
molten salt; and
a liquid metal alloy of the metal M' and the metal M 2 positioned below the eutectic
composition;
wherein a density of the molten salt may be smaller than a density of the metal oxide,
the metal oxide and the metal M 3 may react to reduce the metal MI, and
the metal M 2 may form an eutectic phase with the metal M1 .
[Advantageous Effects]
The present disclosure provides a system optimized for obtaining the desired metal from
a metal oxide without using a metal chloride or chloride at all as a flux, and a method for producing
this metal. Therefore, the present disclosure may solve the above-mentioned environmental
matters of a Kroll process and cost matters due to corrosion of a cell.
The present disclosure is characterized by producing a liquid metal alloy of metal M, and
metal M 2 forming an eutectic phase with each other. Since a melting point of metal M, is lowered
by a eutectic reaction, reduction may be effectively performed at a relatively low temperature,
which may significantly save energy and lead to cost reduction.
The present disclosure is obtained in a liquid alloy state (liquid metal alloy of metal M,
and metal M 2 ) by the eutectic reaction, so that the metal alloy itself may be used as a final product.
In addition, the metal M' may be obtained by electrorefining of the obtained metal alloy. The
liquid alloy thus obtained may be thoroughly separated from an environment in which oxygen may
present, and thus contamination by oxygen may be significantly prevented. That is, it is possible
to obtain a high-purity metal alloy and metal M' according to the above aspects.
In addition, according to the present disclosure, it is easy to adjust the ratio of the target
alloy, and a high-purity metal may be produced through an electrorefining technique using a finally
produced alloy metal.
In the present disclosure, a recovery rate of high-grade metal M, is high, and the separation
of a final product and a reaction product is easy, so that continuous operation is possible.
[Brief Description of Drawings]
FIG. 1 shows a process chart showing a process for reducing metal M, from a metal oxide
according to an embodiment of the present disclosure.
FIG. 2 shows a diagram illustrating a process procedure of a method of reducing metal M,
from the metal oxide according to an embodiment of the present disclosure.
FIG. 3 shows a diagram and a result table showing a difference in a volatilization rate
between a fluoride-based flux and a chloride-based flux.
FIG. 4 shows a diagram showing the vapor pressure of a fluoride-based flux and a
chloride-based flux according to temperature.
FIG. 5 shows a photograph of a metal alloy produced according to an embodiment of the
present disclosure.
FIG. 6 shows a diagram and a result table of elements analyzed using an energy dispersive
spectrometer (EDS) after cutting the metal alloy produced according to an embodiment of the
present disclosure.
FIG. 7 shows a result table of measuring a oxygen content present in the metal alloy
produced according to Example 2 of the present disclosure using ELTRA ONH2000.
[Modes of the Invention]
Hereinafter, the intention, operation, and effect of the present disclosure will be described
in detail through the embodiments of the present disclosure and specific descriptions, and
examples to aid understanding and practice thereof, However, the following description and
embodiments are presented as examples to aid understanding of the present disclosure as described
above, and the scope of the invention disclosure is not limited or limited thereto.
Prior to the detailed description of the present disclosure, the terms or words used in the
specification and claims should not be interpreted as limiting in a sense in the related art or a
preliminary sense, and the inventor should be interpreted in a sense and a concept that are
consistent with the technical concept of the present disclosure given the principle that the concepts of the terms may be appropriately defined in order to explain its own invention in its best mode.
Accordingly, it should be understood that the configuration of the embodiments described
herein are only preferred embodiments of the present disclosure and are not intended to vary all of
the spirit of the invention, and that there may be various equivalents and modifications that may
be substituted for them at the time of this application.
In this specification, the singular expression includes the plural expression unless the
context clearly dictates otherwise. In this specification, the terms "comprises," "includes," or
"has" and the like are intended to designate the presence of the features, numbers, steps,
components, or combinations thereof that are implemented, and are not to be understood as
precluding the possibility of the presence or addition of one or more other features or numbers,
steps, components or combinations thereof.
As used herein, the term "loading" may be used interchangeably with "put", "introduction",
"inflow", and "injection" in this specification, and may be understood to mean bringing or putting
any material, such as a raw material, into a place where it is needed.
Hereinafter, the present disclosure will be described in detail in the order of reduction
method of metal M1 , a reduction system, and examples.
1. Reduction method of metal M1
A method of reducing metal M1 from a metal oxide according to the present disclosure
may include:
forming a molten salt of a fluoride-based flux in an cell;
putting, into the cell, a metal M 2 forming an eutectic phase with the metal MI, and a
reducing agent including a metal M 3 to produce an eutectic composition of the metal M 2 and the metal M3 ; and reducing the metal M' by reacting the metal oxide with the eutectic composition and forming a liquid metal alloy with the reduced metal M' and M 2
. In the method of the present disclosure, the molten salt of the fluoride-based flux may be
smaller than a density of the eutectic composition of the metal M2 and the metal M 3 and the metal
oxide.
In the method of the present disclosure, a molten salt of the fluoride-based flux has a
volatilization rate of 10% by weight or less, specifically 5% by weight or less, and more
specifically 2% by weight or less for 10 hours at 1,600 °C
By using the molten salt of the fluoride-based flux, there is an environmental advantage
in that toxic chlorine gas is not generated, and since its volatilization rate is low, loss of the flux
during the process is small, and it is advantageous in terms of maintenance cost. In particular,
when compared with a chloride-based flux, such as CaCl2, which has a volatilization rate of about
74% by weight (FIG. 3) at 1,600 °C for 10 hours, the advantage of this fluoride-based flux may be
more clearly understood. Here, the volatilization rate may be measured by leaving for a certain
time at a specific temperature and comparing the weight before and after leaving, but Other
methods well known to those skilled in the art may be used, and numerical values in the case of
using other methods may be appropriately converted from the numerical values in the present
disclosure. However, since the flux of the present disclosure is used in a process of reducing a
metal by reacting a metal oxide with a eutectic composition, the volatilization rate should be
measured within a process temperature (900 to 1600 °C) according to the present disclosure. In
particular, since the volatilization rate is higher at higher temperatures, it may be desirable to
measure the volatilization rate at 1600 °C, which is the highest among allowable process temperatures, to ensure process stability.
In the method of the present disclosure, the fluoride-based flux may be a fluoride-based
flux of one or more metals selected from the group of alkali metals and alkaline earth metals, and
determined by considering the relative density difference, a volatilization rate, convenience and
safety of operation, and the like according to the target metal M, and the reducing agent used.
The fluoride-based flux may, for example, be one or more selected from the group consisting of
MgF2, CaF2, SrF2, and BaF2, and specifically may be CaF2.
In the method of the present disclosure, by using an eutectic composition of metal M 2 and
metal M 3 and a fluoride-based flux molten salt having a density lower than that of the metal oxide,
In the step in which the metal oxide reacts with the eutectic composition to reduce the metal M,
and form a liquid metal alloy between the reduced metal M' and the metal M2 , and since the molten
salt of the fluoride-based flux is positioned at the top of the cell, the eutectic composition and the
metal oxide may not be exposed to an external environment, and inflow of oxygen from the outside
maybeprevented. Accordingly, a reduction process of the metal M' is possible even in a normal
air atmosphere other than an inert gas atmosphere.
In addition, by using a fluoride-based flux with a low volatilization rate, it is advantageous
for large-scale industrialization because it allows harmful gases to be disloaded in an acceptable
amount even in a normal air atmosphere, thereby increasing the convenience and safety of
operation, and significantly lowering a degree of corrosion of equipment than used fluxes in the
related art.
The metal M' is not particularly limited, but specifically may be one selected from the
group consisting of Ti, Zr, Hf, W, Fe, Ni, Zn, Co, Mn, Cr, Ta, Ga, Nb, Sn, Ag, La, Ce, Pr, Nd, Pm,
Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Ac, Th, Pa, U, Np, Pu, Am, Cm, Bk, Cf, Es, Fm, Md, and
No, more specifically, one selected from the group consisting of Ti, Zr, W, Fe, Ni, Zn, Co, Mn,
Cr, Ta, Er, and No, and even more specifically, one selected from the group consisting of Ti, Zr,
W, Fe, Ni, Zn, Co, Mn, and Cr, and in particular, Ti, Zr, or W.
In the method of the present disclosure, the metal M 2 is not limited as long as it may form
an eutectic phase with the metal M', for example, the metal M 2 may be one or more selected from
the group consisting of Cu, Ni, Sn, Zn, Pb, Bi, Cd, and alloys thereof, and specifically, Cu.
In the method of the present disclosure, a reducing agent including the metal M 3 is not
limited as long as it may reduce the metal oxide including the metal M, for example, the metal
M3 may be one or more selected from the group consisting of Ca, Mg, Al, and alloys thereof.
Specifically, the metal M 3 may be Mg.
In the method of the present disclosure, the metal oxide may include one or more selected
from the group consisting of MxOz and M 1xM 3 yOz, where x and y are real numbers of 1 to 3,
respectively, and z is a real number of 1 to 4.
Non-limiting examples of the above metal oxides for ease of understanding may include
one selected from the group consisting of ZrO2, TiO 2 , MgTiO3, HfO 2 , Nb 205 , Dy203, Tb 4 0 7 , W0 3
, C030 4 , MnO, Cr203, MgO, CaO, A12 0 3 , Ta205, Ga203, Pb3 0 4 , SnO, NbO, and Ag20, or a
combination of two or more of these.
When a composite oxide (M1 xM 3 yOz) of the metal M' and the metal M 3 is used as the
metal oxide, a process of reducing the metal M' by reacting with the eutectic composition of the
metal M2 and the metal M 3 may be faster. According to the findings of the present disclosure, in
the case of using the complex oxide (MxM 3 yOz), the time required for reduction may be reduced
by at least 1/3 to 1/10 compared to the case of using Mx0z. That is, when the composite oxide
of the metal M' and the metal M 3 is used as the metal oxide, a reaction rate between the metal oxide and the eutectic composition may be faster than when only the oxide of the metal M' is used.
In addition, in the case of using M'xM 3yO, there is an advantage in that a ratio of M' and M 2 in
the liquid metal alloy produced according to the present disclosure may be more widely adjusted.
Moreover, when MxM 3yOz is used, a required amount of M 3 used as a reducing agent is
significantly reduced compared to the case of using MxOz. For example, when Ti is used as the
metal M' and Ca is used as the metal M 3 , oxide of the metal M' may be TiO 2 , and the composite
oxide of the metal M' and the metal M 3 may be CaTiO3.
Unlike the Kroll process in the related art, the method according to the present disclosure
is different in that it uses a metal oxide instead of a metal chloride as a raw material. A raw
material usually found in nature includes an oxide of the metal M', and a pre-treatment process of
substituting the metal oxide with a chloride is involved in order to use the oxide in the Kroll process.
When such a pre-treatment process is performed, it itself causes an increase in process cost.
Moreover, hydrochloric acid is used in the pre-treatment process of replacing metal oxide with
chloride, and this process promotes corrosion of manufacturing equipment due to strong acidity,
and toxic chlorine gas may be generated during the process, which may cause environmental
matters. Since the method according to the present disclosure does not require a pre-treatment
process for substituting the metal oxide with chloride, process cost is lower than that of the Kroll
process and there are advantages in not causing environmental matters.
In the method of the present disclosure, a process of reducing the metal M, by reacting
the metal oxide with the eutectic composition may be performed in air or in fluoride. Since a
density of the molten salt of the fluoride-based flux is lower than that of the eutectic composition
and the metal oxide, the molten salt of the fluoride-based flux is positioned at the top of the cell,
and the eutectic composition and the input metal oxide are positioned below the molten salt of the fluoride-based flux. Due to this, since the eutectic composition and the introduced metal oxide can present in a state that is not exposed to an external environment due to the molten salt of the fluoride-based flux and the cell, a process of reducing the metal M, by reacting the metal oxide with the eutectic composition may be performed even in a normal atmosphere other than an inert gas atmosphere. Moreover, since a volatilization rate of the molten salt of the fluoride-based flux is relatively low, even when the process is performed in an atmospheric atmosphere, the generation of toxic gases is reduced, and the corrosion of equipment used in the process is significantly reduced, a harmful environment is not created for operators, and large-scale industrialization can be achieved.
In the method of the present disclosure, a method of reducing the metal M, may be
performed at least a temperature at which the fluoride-based flux can be melted, the eutectic
composition can be produced, and a process of reducing metal M1 by reacting the metal oxide with
the eutectic composition can be performed. For example, a process of reducing the metal M, by
reacting the metal oxide with the eutectic composition may be performed at 900 °C or more. In
addition, he method can be performed at a temperature below which the molten salt of the fluoride
based flux does not evaporate excessively, and considering the energy efficiency according to the
heating of the furnace, the method may be performed at 1800 °C or less, 1700 °C or less, 1600 °C
orless,or1600°Corless. Accordingly, a process of reducing the metal M, by reacting the metal
oxide with the eutectic composition may be performed in the range of 900 to 1600 °C.
As an example, when the metal M' is Ti, the metal oxide (Mx0z) is TiO 2 , the metal M 2 is
Cu, and the metal M 3 is Ca, the metal Ti is reduced according to the following Scheme 1-1 and
Scheme 1-2, and a metal M 3 oxide (M 3aO) can then be separated while the liquid metal alloy CuTi
is obtained. Here, a and b are a real number from 1 to 3, respectively.
[Scheme 1-1]
2Ca + TiO2 -> Ti + 2CaO
[Scheme 1-2]
Ti + Cu + 2CaO -> CuTi (Alloy) + 2CaO (separation)
As another example, when the metal M' is Ti, the metal oxide (MIxM 3yOz) is CaTiO3, the
metal M 2 is Cu, and the metal M 3 is Ca, the metal Ti is reduced according to the following Scheme
1-1 and Scheme 1-2, and a metal M 3 oxide (M 3 aOb) can then be separated while the liquid metal
alloy CuTi is obtained.
[Scheme 2-1]
2Ca + CaTiO3 -> Ti + 3CaO
[Scheme 2-2]
Ti + Cu + 3CaO -> CuTi (alloy) + 3CaO (separation)
The metal M 3 oxide (M 3 aO) produced according to the above reaction is a kind of by
product, and it is necessary to continuously remove the by-products in order to enable a continuous
process. The by-products may not be completely soluble in the molten salt and it may not be
easy to remove the by-products or run the process continuously. The method of the present
disclosure may further include forming slags of by-products generated in the process of reducing
the metal M' by reacting the metal oxide with the eutectic composition and the molten salt of the
fluoride-based flux by putting a slag-forming additive. When slags are formed, viscosity is
relatively reduced compared to the case where by-products and the molten salt of the fluoride
based flux are present, fluidity is increased, continuous removal of slags including by-products is
possible, and furthermore, a continuous process can be made possible.
Examples of the slag-forming additive to achieve the above effect may include one or
more selected from the group consisting of MgO, CaO, FeO, BaO, SiO 2 , and A1 2 0 3 , but are not
limited thereto.
A method of reducing metal M' from a metal oxide according to the present disclosure
may further include forming a layer in which the liquid metal alloy is positioned at a bottom of the
cell and separated from the eutectic composition, and continuously obtaining the liquid metal alloy
through a lower portion of the cell; and forming a distinct layer on top of the eutectic composition
using the slags, and continuously removing the slags through a top of the cell. By forming a layer
in which the liquid metal alloy is positioned at a bottom of the cell and separated from the eutectic
composition, a liquid metal alloy may be continuously tapped from a lower portion of the cell. In
addition, input of the slag-forming additive causes the slag to form as a distinct layer on an upper
portion of the eutectic composition, and the slag is continuously removed through the upper portion
of the cell, so that by-products generated in the reduction process of metal oxides can be
continuously removed. Accordingly, by continuously removing the reaction product formed
when the metal oxide is input to the eutectic composition from the cell, after inputting an amount
of the metal oxide, the liquid metal alloy of the metal M1 and the metal M2 may be obtained without
interruption of the process by continuously inputting the metal oxide rather than all reactions being
terminated. At this time, a method known to those skilled in the art may be used for continuously
obtaining a liquid metal alloy through the lower portion of the cell or continuously removing slags
through the upper portion of the cell.
After the slags are removed through removing the slags and the fluoride-based flux
through the upper portion of the cell, the fluoride-based flux is supplemented during a process
operation to maintain the balance of a reaction system and enable a continuous process. At this time, the fluoride-based flux may be continuously separated from the removed slags, and the separated fluoride-based flux may be input into the cell again.
Cooling for solidification of the obtained liquid metal alloy may be performed. Since the
liquid metal alloy is in a state in which the metal M' and the metal M2 are homogeneously mixed,
the structure of the alloy obtained after solidification is greatly affected by a cooling rate of the
liquid metal alloy. The cooling rate can stably form an intermetallic compound phase, in the
temperature range in which the process according to the present disclosure is performed, it may be
slowly cooled to room temperature at a rate of 20 °C/min, so that a tissue structure in which the
intermetallic compound phases of M' and M 2 are continuously connected to each other can be
produced. When the cooling rate is excessively fast outside a suggested range, a structure in
which a large amount of fine intermetallic compound particles are dispersed and incorporated into
the metal M' matrix is obtained, and thus there is a risk that a continuous and rapid mass transfer
path of metal M' may not be formed. When the cooling is excessively slow, the microstructural
benefit is negligible, but as the time required for the process becomes excessively long, the cooling
rate may be substantially 1 C/min or more, and more substantially 5 °C/min or more.
The method according to the present disclosure may further include obtaining an alloy
including the metal M' and the metal M 2 , and then electrolytically refining the obtained alloy
including the metal M' and the metal M 2 to obtain the metal MI.
Obtaining the metal M' by performing the electrorefining may be solidifying the obtained
liquid metal alloy to obtain a solid alloy, electrolytically refining the solid alloy, and recovering
the metal M' from the alloy.
In some cases, prior to electrorefining the solidified alloy, the flux that may remain in the
liquid metal alloy may be removed, this can be achieved, for example, by heat treating the liquid metal alloy in a vacuum or inert gas atmosphere to cause the flux to distill off. A distillation temperature (heat treatment temperature) is not particularly limited as long as the temperature is higher than a boiling point of the flux used in the system of the present disclosure, for example, the temperature may be 2,500 °C or more, and reduced pressure may be performed to lower the distillation temperature and increase efficiency. In order to effectively prevent the liquid metal alloy from being oxidized again, it may be advantageous to perform the distillation in a vacuum atmosphere and under an inert gas.
The present disclosure provides a metal alloy of the metal M' and the metal M2 obtained
by any method or combination thereof described in the specification of the present disclosure.
For example, the metal alloy of the metal M' and the metal M2 can be obtained by a method of
reducing metal M' from a metal oxide, including: forming a molten salt of a fluoride-based flux
in an cell; putting, into the cell, a reducing agent including a metal M 2 forming an eutectic phase
with the metal M', and a metal M3 to produce an eutectic composition of the metal M 2 and the
metal M 3 ; and reducing the metal M' by reacting the metal oxide with the eutectic composition
and forming a liquid metal alloy with the reduced metal M' and M2 . For example, the metal alloy
of the metal M' and the metal M 2 may be made in an atmosphere or obtained from a process
performed in a range of 900 to 1600 °C. For example, the metal alloy of the metal M, and the
metal M 2 may be obtained by a method including forming slags of the molten salt and a by-product
generated in a process of reducing the metal M' by adding a slag-forming additive to react the
metal oxide with the eutectic composition. In addition, the metal alloy of the metal M, and the
metal M 2 of the present disclosure may be obtained by any method or a combination thereof
described in the specification of the present disclosure.
In one embodiment, the metal alloy of the metal M' and the metal M 2 is a high-grade metal alloy with a residual content of 0.1% by weight or less, specifically 0.01% by weight or less, and more specifically 0.001% by weight or less, based on a total weight of the metal alloy. Inaddition, the metal alloy of the metal M1 and the metal M 2 is a high-grade metal alloy with an oxygen content of 1,800 ppm or less, specifically 1,500 ppm or less, and more specifically 1,200 ppm or less.
In addition, in a liquid alloy (Ml and M2 are liquid metal alloys) obtained according to the
method of the present disclosure, the metal alloy itself may be used as a final product. M, is
often used industrially in the form of an alloy, and when M' can be produced with only a single
metal, as in the Kroll process in the related art, a post-processing process for forming an alloy with
another metal may be required. However, the present disclosure has high process efficiency in
that a final product may be obtained in the form of a metal alloy of M, and M 2 simultaneously with
reduction without such a post-treatment process. Moreover, the reduced metal produced through
the Kroll process in the related art has a low production of high grade (grade 1) metal having a low
oxygen content and a relatively high residual oxygen content. Therefore, even when a metal
alloy is produced using the reduced metal produced by the Kroll process, there is a limit in that the
residual oxygen content is high. On the other hand, most of the metal alloys produced according
to the present disclosure have a very low oxygen content and are of high quality grade. For
example, when M' is Ti, the method according to the present disclosure yields a high-grade metal
as high as 98% or more, but it is known that the crawl process in the related art yields less than
% of high-grade metal, and through this, superiority of the present disclosure can be more clearly
understood.
2. System for reducing M'
A system for reducing metal M' from a metal oxide according to the present disclosure may include: an cell; a molten salt of a fluoride-based flux positioned in the cell; an eutectic composition of metal M 2 and metal M 3 positioned at a lower portion of the molten salt; and a liquid metal alloy of the metal M' and the metal M 2 positioned below the eutectic composition; wherein a density of the molten salt may be smaller than a density of the metal oxide, the metal oxide and the metal M 3 may react to reduce the metal MI, and the metal M 2 may form an eutectic phase with the metal M1
. In one embodiment, the cell may be an electrolytic reduction cell or the like, a high
frequency melting furnace may be used to achieve a desired temperature range, or an electric
furnace may be used depending on a target metal alloy, but is not limited thereto. Considering a
reaction temperature range, reactivity, and the like, all cells and furnaces that are easy for a person
skilled in the art may be used.
In one embodiment, a mass ratio of the molten salt of the fluoride-based flux to the
reaction by-product may be 5:1 to 2:1, preferably 3:1, but is not limited thereto, for smooth
separation of the liquid metal alloy and the reaction by-product.
In one embodiment, the flux may further include an oxide of one or two or more metals
selected from an alkali metal and an alkaline earth metal group as a reactive additive. A content
of the reactive additive may be 0.1 to 25% by weight based on a total weight of the flux. The
reactive additive may include, but are not limited to, LiO, NaO, SrO, CsO, KO, CaO, BaO, or
mixtures thereof. The reactive additive contained in the flux may enable easier reduction of a metal oxide contained in a raw material module.
In one embodiment, a cell similar to that of FIG. 1 may be used to perform a production
method an alloy metal of the present disclosure. For example, The fluoride-based flux is loaded
into an cell 1 and melted to form a molten salt 5, and a reducing agent including metal M 2 forming
an eutectic phase with metal M, and metal M3 is input into an cell to produce an eutectic
composition 6 of the metal M 2 and the metal M3 . Since the density of the molten salt of the
fluoride-based flux is less than that of the eutectic composition, the molten salt 5 of the fluoride
based flux is positioned on the eutectic composition 6. Thereafter, a metal oxide 10 is loaded
into the cell using the raw material input device 1, and the oxide is reacted with the eutectic
composition 6 to prepare a liquid metal alloy 7 of the metal M' and the metal M 2 , and after the
reaction is completed, a slag-forming additive 9 is input into the reaction by-product positioned
between the liquid metal alloy and the flux to slag the by-product. After that, the liquid metal
alloy 7 is obtained through a tapping portion 8 connected to a lower portion of the cell through the
lower portion of the cell. Since the slags are positioned at a upper portion of the cell, about 50
% of the slags are removed by tilting the cell, and a new fluoride-based flux is input into about
to 50% of residual slags through an flux input device 2 to form a new flux layer. Thereafter,
again, the metal oxide 10 is loaded into the cell using the raw material input device 1 and reacted
with the eutectic composition 6, and a process of producing the liquid metal alloy 7 may be
repeated. In all stages of the process, such as before removing slags or tilting the cell to remove
slags, the liquid metal alloy 7 produced in the lower portion of the cell is continuously obtained
through the tapping portion 8 in the lower portion of the cell. The cell may use, for example, a
high-frequency melting furnace 3 to facilitate stirring, but is not limited thereto.
3. Examples
Hereinafter, examples will be described in detail, through which the action and effect of
the present disclosure will be demonstrated. However, the following examples are only
presented as examples of the invention disclosure, and the scope of the invention disclosure is not
determined thereby.
<Example 1>
A system as shown in FIG. 1 was used and proceeded according to a process sequence of
FIG. 2. Flux CaF2 (40.8 g) was weighed in a resistance heating furnace, input into an cell, and
then heated to about 1415 °C to produce a molten salt of a fluoride-based flux (FIG. 2A).
52.8 g and 72.3 g of Cu(s) and Ca(s) were weighed, input into an cell, and melted to
produce an eutectic composition (FIG. 2B).
72.1 g of TiO 2 (average particle size of 100 m) as a metal oxide was weighed and reacted
for 10 hours (FIGS. 2c and 2d).
In order to remove by-products, 200 g of A1 2 0 3 powder and 100 g of CaO as slag-forming
additives were input to slags (FIG. 2E), and then slowly cooled in the furnace. The process was
performed in an air atmosphere.
<Example 2>
A system as shown in FIG. 1 was used and proceeded according to a process sequence of
FIG. 2. Flux CaF2 (40.8 g) was weighed in a resistance heating furnace, input into an cell, and
then heated to about 1415 °C to produce a molten salt of a fluoride-based flux (FIG. 2A).
60 g and 65.5 g of Cu(s) and Ca(s) were weighed, input into a cell, and melted to produce
an eutectic composition (FIG. 2B).
111 g of CaTiO3 as a metal oxide was weighed and reacted for 2 hours (FIG. 2c and 2d).
In order to remove by-products, 200 g of A1 2 0 3 powder and 100 g of CaO as slag-forming
additives were input to slags (FIG. 2E), and then slowly cooled in the furnace. The process was
performed in an air atmosphere.
<Experimental Example 1>
A volatilization rate of a fluoride-based flux and a chloride-based flux were measured.
500 g of each flux (weight before loading) was weighed and input into a crucible, and weight
(weight after loading) of the flux after loading the crucible to a melting furnace and leaving the
flux at 1,600 °C for 10 hours was measured. The volatilization rate was evaluated using the
following method.
- Volatilization rate: (weight before loading - weight after loading) / (weight before
loading) x 100%
As a result, it was confirmed that CaF2 used as the fluoride-based flux showed a low
volatilization rate of 1.8% by weight, but CaCl2, a chloride-based flux, showed a high volatilization
rate of about 74% by weight (FIG. 3).
Regarding a volatilization rate of CaF2, a fluoride-based flux, and a volatilization rate of
CaC2, a chloride-based flux, measured in each temperature range, it may be seen that a vapor
pressure of the fluoride-based flux is remarkably low based on a process temperature at which this
process is performed (FIG. 4), indicating that the volatilization rate in the process of the fluoride
based flux is remarkably low.
From this, it is preferable to use a fluoride-based flux having a low volatilization rate for
an efficient process as described above.
<Experimental Example 2>
The properties of the alloys obtained in Examples 1 and 2 were evaluated using the following method.
- Recovery rate: 100 - {(1st weight - 2nd weight)/2nd weight x 100%}
- Residual impurity content: The produced alloy was cut and the inside of the alloy was
confirmed using an energy dispersion spectrum.
- Oxygen content: The oxygen content present in the alloy was measured using an ELTRA
ONH2000.
[Table 1]
Results of energy dispersion Recovery spectrum Oxygen 1st 2nd content weight weight rate (%) Ti (% by Cu (% by (ppm) weight) weight) Example 1 96 83.9 87.4 27.3 72.7 1162.69 Example 2 99.16 95.86 96.7 40.81 59.19 1126.08
*1st weight: Total amount of Cu put into the initial electrolytic bath + Chemical theoretical
reduction amount of Ti included in metal oxide.
**1st weight: Total amount of CuTi obtained
From the results of Table 1, it may be seen that the alloys of Examples produced according
to the present disclosure showed a high recovery rate, and that a high-purity alloy was obtained
that was substantially free of metal or oxygen used as a reducing agent. That is, it was confirmed
that, unlike a presenting process, which was possible only in an inert gas atmosphere as above,
even though the process proceeded in an air atmosphere, the recovery rate of the target metal was
better and the oxygen content was significantly lower.
Although the present disclosure has been described with reference to embodiments, those skilled in the art will be able to make various applications and modifications within the scope of the present disclosure based on the above information.
Claims (19)
- [CLAIMS][Claim 1]A method of reducing metal M' from a metal oxide, comprising:forming a molten salt of a fluoride-based flux in an cell;putting, into the cell, a metal M2 forming an eutectic phase with the metal M1 , and areducing agent including a metal M 3 to produce an eutectic composition of the metal M2 and themetal M3 ; andreducing the metal M' by reacting the metal oxide with the eutectic composition andforming a liquid metal alloy with the reduced metal M' and M 2, wherein density of the molten salt is less than density of the eutectic composition and themetal oxide.
- [Claim 2]The method of claim 1, wherein the molten salt has a volatilization rate of 10% by weightor less at 1,600 °C for 10 hours.
- [Claim 3]The method of claim 1, wherein the fluoride-based flux is one or more selected from thegroup consisting of MgF2, CaF2, SrF2, and BaF2.
- [Claim 4]The method of claim 3, wherein the fluoride-based flux is CaF2.
- [Claim 5]The method of claim 1, wherein the metal M' is one or more selected from the groupconsisting of Ti, Zr, Hf, W, Fe, Ni, Zn, Co, Mn, Cr, Ta, Ga, Nb, Sn, Ag, La, Ce, Pr, Nd, Pm, Sm,Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Ac, Th, Pa, U, Np, Pu, Am, Cm, Bk, Cf, Es, Fm, Md, and No.
- [Claim 6]The method of claim 1, wherein the metal M2 is one or more selected from the groupconsisting of Cu, Ni, Sn, Zn, Pb, Bi, Cd, and alloys thereof.
- [Claim 7]The method of claim 6, wherein the metal M2 is Cu.
- [Claim 8]The method of claim 1, wherein the metal M 3 is one or more selected from the groupconsisting of Ca, Mg, Al, and alloys thereof.
- [Claim 9]The method of claim 1, wherein the metal oxide includes one or more selected from thegroup consisting of MxOz, and MIxM 3yOz:wherein x and y are a real number from 1 to 3, respectively, and z is a real number from1 to 4.
- [Claim 10]The method of claim 1, wherein a process of reducing the metal M, by reacting the metaloxide with the eutectic composition is performed in air or in fluoride.
- [Claim 11]The method of claim 1, wherein a process of reducing the metal M, by reacting the metaloxide with the eutectic composition is performed in a range of 900 to 1,600 °C
- [Claim 12]The method of claim 1, further comprising forming slags of the molten salt and a byproduct generated in a process of reducing the metal M' by reacting the metal oxide with theeutectic composition by adding a slag-forming additive.
- [Claim 13]The method of claim 12, wherein the slag-forming additive comprises one or moreselected from the group consisting of MgO, CaO, FeO, BaO, SiO 2 , and A1 2 0 3.
- [Claim 14]The method of claim 12, further comprising:forming a layer in which the liquid metal alloy is positioned at a bottom of the cell andseparated from the eutectic composition, and continuously obtaining the liquid metal alloy througha lower portion of the cell; andforming a distinct layer on top of the eutectic composition using the slags, andcontinuously removing the slags through a top of the cell.
- [Claim 15]The method of claim 1, further comprising electrorefining the liquid metal alloy toproduce the metal M1 .
- [Claim 16]A metal obtained by the method of claim 15.
- [Claim 17]A metal alloy obtained by the method of claim 1.
- [Claim 18]The method of claim 17, wherein a residual content of the metal M 3 is 0.1% by weight orless based on the total weight of the metal alloy, and a oxygen content is 1,800 ppm or less.
- [Claim 19]A system for reducing metal M' from a metal oxide, comprising:an cell; a molten salt of a fluoride-based flux positioned in the cell; an eutectic composition of metal M 2 and metal M 3 positioned at a lower portion of the molten salt; and a liquid metal alloy of the metal M' and the metal M 2 positioned below the eutectic composition; wherein a density of the molten salt is smaller than a density of the metal oxide, the metal oxide and the metal M 3 react to reduce the metal M, and the metal M2 forms an eutectic phase with the metal M1.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020200154083 | 2020-11-17 | ||
KR10-2020-0154083 | 2020-11-17 | ||
PCT/KR2021/003849 WO2022108007A1 (en) | 2020-11-17 | 2021-03-29 | Reduction method and system for high-melting-point metal oxide, using fluoride-based electrolytes |
Publications (1)
Publication Number | Publication Date |
---|---|
AU2021384253A1 true AU2021384253A1 (en) | 2023-06-29 |
Family
ID=81709275
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
AU2021384253A Pending AU2021384253A1 (en) | 2020-11-17 | 2021-03-29 | Reduction method and system for high-melting-point metal oxide, using fluoride-based electrolytes |
Country Status (8)
Country | Link |
---|---|
US (1) | US20240002974A1 (en) |
EP (1) | EP4249644A1 (en) |
JP (1) | JP2023550382A (en) |
KR (2) | KR20220067533A (en) |
CN (1) | CN116685720A (en) |
AU (1) | AU2021384253A1 (en) |
CA (1) | CA3201236A1 (en) |
WO (1) | WO2022108007A1 (en) |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5035404A (en) | 1990-09-13 | 1991-07-30 | Westinghouse Electric Corp. | Retort assembly for kroll reductions |
JPH06146049A (en) * | 1992-10-30 | 1994-05-27 | Kobe Steel Ltd | Molten salt electrolytic sampling method for high-fusion-point active metal such as titanium |
JPH1171694A (en) * | 1997-08-29 | 1999-03-16 | Mitsubishi Materials Corp | Reduction of metallic oxide, and device therefor |
US7381366B2 (en) * | 2003-12-31 | 2008-06-03 | General Electric Company | Apparatus for the production or refining of metals, and related processes |
EP2014787B1 (en) * | 2006-10-03 | 2017-09-06 | JX Nippon Mining & Metals Corporation | Cu-Mn ALLOY SPUTTERING TARGET |
KR101793471B1 (en) | 2016-07-20 | 2017-11-06 | 충남대학교산학협력단 | Refining Method of Metal Using Electroreduction and Electrorefining process |
KR101757626B1 (en) | 2016-09-13 | 2017-07-14 | 충남대학교산학협력단 | Manufacturing system of metal comprising zirconium |
KR101878652B1 (en) | 2017-07-12 | 2018-07-16 | 충남대학교산학협력단 | Refining Method of Metal Using Integrated Electroreduction and Electrorefining process |
KR102004920B1 (en) * | 2019-01-28 | 2019-07-29 | 한국지질자원연구원 | Metal refining method by using liquid metal cathode |
-
2021
- 2021-03-29 EP EP21894786.9A patent/EP4249644A1/en active Pending
- 2021-03-29 WO PCT/KR2021/003849 patent/WO2022108007A1/en active Application Filing
- 2021-03-29 JP JP2023529973A patent/JP2023550382A/en active Pending
- 2021-03-29 AU AU2021384253A patent/AU2021384253A1/en active Pending
- 2021-03-29 CA CA3201236A patent/CA3201236A1/en active Pending
- 2021-03-29 CN CN202180084243.6A patent/CN116685720A/en active Pending
- 2021-03-29 US US18/253,348 patent/US20240002974A1/en active Pending
-
2022
- 2022-05-11 KR KR1020220057883A patent/KR20220067533A/en not_active Application Discontinuation
-
2023
- 2023-07-03 KR KR1020230085699A patent/KR20230107170A/en not_active Application Discontinuation
Also Published As
Publication number | Publication date |
---|---|
EP4249644A1 (en) | 2023-09-27 |
CN116685720A (en) | 2023-09-01 |
KR20230107170A (en) | 2023-07-14 |
US20240002974A1 (en) | 2024-01-04 |
WO2022108007A1 (en) | 2022-05-27 |
JP2023550382A (en) | 2023-12-01 |
KR20220067533A (en) | 2022-05-24 |
CA3201236A1 (en) | 2022-05-27 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Fray | Emerging molten salt technologies for metals production | |
KR101269796B1 (en) | High-purity ytterbium, sputtering target made of high-purity ytterbium, thin film containing high-purity ytterbium, and method for producing high-purity ytterbium | |
EP3161189B1 (en) | Method and apparatus for electrolytic reduction of a feedstock comprising oxygen and a first metal | |
AU4277099A (en) | Removal of oxygen from metal oxides and solid solutions by electrolysis in a fused salt | |
EP3561091A1 (en) | A method for extraction and refining of titanium | |
JP5445725B1 (en) | Method for producing Al-Sc alloy | |
Mullins et al. | Plutonium electrorefining | |
US20240002974A1 (en) | Reduction method and system for high-melting-point metal oxide, using fluoride-based electrolytes | |
EP4249643A1 (en) | Reduction system and method for high-melting point metal oxides, using liquid metal crucible | |
JP2002129250A (en) | Method for producing metallic titanium | |
CA3071863C (en) | Electrolytic production of reactive metals | |
JP2019026871A (en) | Manufacturing method of rare earth fluoride | |
WO2009110819A1 (en) | Method for producing chemically active metals and a device for carrying out said method | |
US20240191321A1 (en) | Semi-continuous rare earth metal production | |
WO2010131970A1 (en) | Process for separating hafnium and zirconium | |
JPH05331589A (en) | Production of rare earth-iron alloy | |
CN115305520A (en) | Method for producing rare earth metals | |
Sokhanvaran et al. | Advances in Electrometallurgy for Sustainable Metal Production | |
WO2012143719A2 (en) | Methods and apparatus for the production of metal | |
AU2006203344A1 (en) | Removal of substances from metal and semi-metal compounds |