WO2010137555A1 - 精製された金属又は半金属の製造方法 - Google Patents
精製された金属又は半金属の製造方法 Download PDFInfo
- Publication number
- WO2010137555A1 WO2010137555A1 PCT/JP2010/058739 JP2010058739W WO2010137555A1 WO 2010137555 A1 WO2010137555 A1 WO 2010137555A1 JP 2010058739 W JP2010058739 W JP 2010058739W WO 2010137555 A1 WO2010137555 A1 WO 2010137555A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- alloy
- cathode
- electrolysis
- metal
- metalloid
- Prior art date
Links
Images
Classifications
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/02—Silicon
- C01B33/037—Purification
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B1/00—Electrolytic production of inorganic compounds or non-metals
- C25B1/01—Products
- C25B1/33—Silicon
-
- 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
- C25C7/00—Constructional parts, or assemblies thereof, of cells; Servicing or operating of cells
- C25C7/06—Operating or servicing
- C25C7/08—Separating of deposited metals from the cathode
Definitions
- the present invention relates to a method for producing a refined metal or metalloid.
- Metallurgical grade silicon is produced by mixing carbon and silica and reducing it with an arc furnace. Trichlorosilane is synthesized by the reaction of the metallurgical grade silicon and HCl, and purified by rectification, and then reduced at a high temperature using hydrogen to produce semiconductor grade silicon. At present, non-standard products generated when manufacturing the above-mentioned semiconductor grade silicon are used as the main raw materials for solar cell silicon.
- the above semiconductor grade silicon manufacturing method can produce extremely high purity silicon, but the conversion rate from trichlorosilane gas to silicon is low, requiring a large amount of hydrogen to favor the equilibrium to silicon, conversion rate It is necessary to circulate and reuse a large amount of unreacted gas in order to further increase the odor, and since various halogenated silanes are mixed in the unreacted trichlorosilane gas, separation by rectification is required again.
- the production method is expensive because, for example, a large amount of silicon tetrachloride that cannot be finally reduced with hydrogen is produced.
- Patent Documents 1 and 2 discuss electrolytic purification using solid silicon as a cathode
- Patent Document 3 discloses electrolytic purification using molten silicon as a cathode. Is being considered.
- the object of the present invention is to reduce the electrolysis temperature below the melting point of the metal element or metalloid element to be purified, and to suppress the dendritic growth of the purified product and the entrainment of the electrolytic bath in the purified product. It is to provide a method for producing a refined metal or metalloid that can be made.
- the method for producing a refined metal or metalloid according to the present invention includes an electrolysis process, an extraction process, a precipitation process, and a recovery process.
- a metal of the same kind as the metal element or metalloid element contained in the anode with a metal element or metalloid element and a material containing impurities as an anode in an electrolytic bath installed in the electrolytic cell An alloy containing an element or a metalloid element and a solvent metal that does not substantially form a solid solution of the metal element or the metalloid element and having a complete solidification temperature lower than the melting point of the metal element or the nonmetal element
- the metal element or metalloid element in the anode is moved into the cathode alloy by performing electrolysis at an electrolysis temperature at which the cathode alloy can be in a liquid phase.
- the complete solidification temperature of the alloy is a temperature corresponding to the minimum value of the liquidus line in the solid-liquid phase diagram of the alloy, and the alloy cannot contain the liquid phase below the complete solidification temperature. That the solvent metal does not substantially form a solid solution with the metal element or metalloid element means that the solid solubility limit of the solvent metal with respect to the metal element or metalloid element at the complete solidification temperature is 1% by mass or less. .
- the extraction step after the electrolysis step, a part or all of the cathode alloy is taken out of the electrolytic cell.
- the alloy of the cathode whose metalloid element or metal element concentration is higher than that of the composition corresponding to the complete solidification temperature of the alloy may be extracted out of the electrolytic cell.
- the extracted metal alloy or metalloid element is precipitated by cooling the extracted alloy at a temperature higher than the complete solidification temperature and lower than the electrolysis temperature.
- the metal element or metalloid element precipitated from the cooled alloy is recovered.
- an alloy containing a metal element or metalloid element and the solvent metal and having a complete solidification temperature lower than the melting point of the metal element or metalloid element acts as a cathode.
- the electrolysis temperature required for making the cathode into a liquid phase can be lowered.
- the cathode since the cathode is in a liquid phase in the electrolysis process, it is possible to suppress short-circuiting between electrodes due to dendritic growth of metal elements or metalloid elements, and the entrainment of an electrolysis bath in purified metal elements or metalloid elements. .
- the concentration of the metal element or metalloid element in the alloy of the cathode, which is brought into the precipitation process through the electrolytic process and the extraction process, is determined at the complete solidification temperature.
- the metal element or metalloid element contained in the alloy can be selectively precipitated with a high purity by cooling. Thereby, compared with the material which comprises an anode, the purity of the collect
- the solvent metal may have a co-melting point with a metal element or a metalloid element.
- concentration of the metal element or metalloid element in the cathode alloy that is brought into the precipitation process through the electrolytic process and the extraction process is made higher than that of the composition corresponding to the eutectic point, thereby cooling into the alloy.
- the contained metal element or metalloid element can be selectively deposited with higher purity.
- the residue means a residue and may be liquid or solid.
- the metal element or the metalloid element can be transferred continuously and efficiently from the anode to the cathode. Can do.
- the metal element or metalloid element is preferably silicon or germanium.
- the cathode alloy preferably contains one or more metal elements selected from the group consisting of aluminum, silver, copper, and zinc.
- the material of the anode preferably contains one or more metal elements selected from the group consisting of silver, copper, tin, and lead.
- the electrolytic bath preferably contains cryolite.
- the electrolysis temperature is preferably higher than the complete solidification temperature and lower than the melting point of the metal element or metalloid element.
- the electrolysis temperature can be lower than the melting point of the metal element or metalloid element to be purified, and the dendrite growth of the purified product and the entrainment of the electrolytic bath into the purified product can be suppressed.
- a method for producing a refined metal or metalloid element is provided.
- FIG. 1 is a solid-liquid phase diagram of a germanium-lead system.
- FIG. 2 is a solid-liquid state diagram of the silicon-aluminum system.
- the method for producing a refined metal or metalloid according to the present invention mainly comprises an electrolysis step, a removal step, a precipitation step, a recovery step, and a reuse step as necessary.
- a metal element or a metalloid element (hereinafter sometimes referred to as an element to be purified) is a target for purification.
- the element to be purified is not particularly limited.
- metal elements include alkaline earth metals such as beryllium, first transition elements such as scandium, titanium and nickel, second transition elements such as zirconium and yttrium, lanthanoids such as lanthanum, neodymium, europium, dysprosium, rhenium and samarium, Third transition elements such as actinides such as thorium, uranium, plutonium and americium, platinum, and the like can be mentioned.
- metalloid elements examples include silicon, arsenic, antimony, and germanium.
- silicon, germanium, nickel, lanthanoids, and actinoids are preferable, and silicon and germanium are particularly preferable in consideration of ease of recovery from a liquid phase cathode alloy.
- Electrolysis process In the electrolysis process, in the electrolytic bath installed in the electrolytic cell, the element to be purified and the material containing impurities are used as an anode, and the element to be purified and the solvent metal of the same type as the element to be purified contained in the anode are used.
- An alloy having a complete solidification temperature (details will be described later) lower than the melting point of the element to be purified is made to act as a cathode, and the electrolysis is performed at an electrolysis temperature at which the cathode alloy can be in a liquid phase, thereby purifying the anode.
- the target element is moved into the cathode alloy, and an alloy having a concentration of the purification target element higher than the concentration of the purification target element in the alloy composition corresponding to the complete solidification temperature (described later in detail) is obtained at the cathode.
- the material of the anode is a material containing an element to be purified and impurities, and has an aspect of a raw material for purification.
- the material of the anode may be a solid phase at the electrolysis temperature, but is preferably a liquid phase at the electrolysis temperature because of the ease of the electrolytic reaction.
- Impurities contained in the anode material are, for example, elements that are noble than the element to be purified or elements that are baser than the element to be purified.
- the element to be purified is silicon
- examples of elements that are noble than silicon include silver and copper
- examples of elements that are lower than silicon include sodium and magnesium.
- germanium it is the same as that of silicon.
- elements that are more noble than germanium include silver and copper
- examples of elements that are lower than germanium include sodium and magnesium.
- the concentration of the impurity is not particularly limited, and is, for example, several tens of ppm to several% by mass ratio with respect to the material of the anode.
- the material of the anode is preferably an alloy of an element to be purified and an impurity different from the element to be purified (hereinafter sometimes referred to as an anode solvent metal), and has an eutectic point lower than the melting point of the element to be purified. More preferably, it is an alloy. In this case, the alloy preferably has a low vapor pressure and is stable.
- the anode solvent metal is preferably an element more noble than the element to be purified.
- the element to be purified and the anodic solvent metal can be appropriately selected based on, for example, the theoretical decomposition voltage based on thermodynamic data. The theoretical decomposition voltage of each element is illustrated below.
- the theoretical decomposition voltage may be calculated by a method in which the dissolved species of each element is specified and the free energy of formation thereof is examined, or it is estimated based on the free energy of formation of a metal compound such as a halide that can be obtained relatively easily. It may be by a method. For example, when the theoretical decomposition voltage in a fluoride-based molten salt is approximated based on the free energy of formation of each metal fluoride, 1.9 V for Cu, 2.8 V for Fe (II), 3.4 V for Ti (IV), Mn (II) is calculated to be 3.6 V, Si is 3.7 V, Al is 4.1 V, K is 4.6 V, Na is 4.6 V, Mg is 4.7 V, and Ca is 5.3 V.
- the anodic solvent metal includes one or more elements selected from the group consisting of copper, tin, silver, gold, mercury, and lead. In consideration, one or more elements selected from copper, silver, tin, and lead are preferable.
- the anode alloy may contain two or more anode solvent metals.
- the purity of the anode solvent metal is preferably 3N or more, more preferably 5N or more, and particularly preferably 6N or more.
- Metals that are sufficiently noble than silicon, such as silver and copper, and metals that are sufficiently baser than silicon, such as sodium and magnesium, are removed by electrolysis, and metals used as cathode solvent metals, which will be described later, are removed by a deposition process. Since it does not affect the purity of silicon, it is not necessary to consider it as an impurity of the anode solvent metal.
- the cathode contains a purification target element of the same type as the purification target element contained in the anode, and a solvent metal different from the purification target element (hereinafter sometimes referred to as a cathode solvent metal), and the melting point of the purification target element Alloys with lower full solidification temperatures are used.
- the cathodic solvent metal does not substantially form a solid solution with the element to be purified.
- the complete solidification temperature of the alloy is a temperature corresponding to the minimum value of the liquidus line in the solid-liquid phase diagram of the alloy, and the alloy cannot contain the liquid phase below the complete solidification temperature.
- the fact that the cathode solvent metal does not substantially form a solid solution with the element to be purified means that the solid solubility limit of the cathode solvent metal with respect to the element to be purified at the complete solidification temperature is 1% by mass or less.
- the cathode solvent metal may have a eutectic point with the element to be purified. That is, the alloy of the cathode solvent metal and the metal to be purified may have a minimum value in the liquidus.
- the alloy preferably has a low vapor pressure and is stable.
- examples of the cathode solvent metal include one or more selected from the group consisting of aluminum, copper, tin, gallium, indium, silver, gold, mercury, and lead. In view of cost and environmental impact, at least one selected from the group consisting of aluminum, silver, copper and zinc is preferable.
- the alloy may contain two or more cathode solvent metals.
- the solid-liquid phase diagram of the germanium-lead system in which the element to be purified is Ge and the cathode solvent metal is Pb is as shown in FIG. 1, and the complete solidification temperature of this system is the minimum value of the liquidus line A.
- the point B is 327 ° C.
- the concentration of Ge (element to be purified) corresponding to the complete solidification temperature in this alloy is 0 wt%.
- the solid-liquid phase diagram of the silicon-aluminum system in which the element to be purified is Si and the cathode solvent metal is Al is as shown in FIG.
- the complete solidification temperature of this system is 577 ° C., which is the point C indicating the minimum value (minimum value) of the liquidus line A, and the point where the liquidus line takes the minimum value as this point C is called the eutectic point.
- the Si concentration of the composition corresponding to the complete solidification temperature of this alloy is about 12.6 wt%, and this composition corresponds to the eutectic point and is also called the eutectic composition.
- a phase diagram having the same eutectic point as that in FIG. 2 is also shown for alloy systems such as silicon-silver system and germanium-zinc system.
- the purity of the cathode solvent metal is preferably 3N or more, more preferably 5N or more, and particularly preferably 6N or more.
- the content of P and B is preferably 0.5 ppm or less, more preferably 0.3 ppm or less, and particularly preferably 0.1 ppm or less with respect to the cathode solvent metal.
- the element ratio of the alloy of the cathode at the start of electrolysis is not particularly limited, and a cathode solvent metal (including an alloy) that does not contain the element to be purified may be used.
- a cathode solvent metal including an alloy
- the concentration of the element to be purified in the alloy of the cathode needs to exceed that of the composition corresponding to the complete solidification temperature.
- the concentration of the element to be purified at the time of removal needs to be higher than that of the composition corresponding to the eutectic point. In other words, for example, in FIG.
- the concentration of Si as the element to be refined in the alloy at the time of removal needs to exceed 12.6 wt% that of the eutectic composition.
- the saturation concentration of the element to be purified which is the maximum concentration of the element to be purified that the alloy of the cathode can exist as a single phase in the liquid phase, at a predetermined electrolysis temperature is set. It is preferable to increase the concentration of the element to be refined in the cathode alloy by electrolysis until it becomes close.
- the electrolytic bath is not particularly limited as long as it can conduct ions of the element to be purified, but a metal halide is preferable.
- the metal element constituting the metal halide include one or more elements selected from alkali metals, alkaline earth metals, aluminum, zinc, and copper.
- the halogen constituting the metal halide include one or more elements selected from the group consisting of fluorine, chlorine, and bromine. Two or more of these metal halides may be used in combination.
- An example of a mixture of metal halides is a mixture of sodium fluoride and aluminum fluoride. More specifically, as the electrolytic bath, cryolite (3NaF ⁇ AlF 3 ), calcium chloride, and the like are preferable from the viewpoint of industrial availability. These electrolytic baths are used in a molten state.
- the purity of the electrolytic bath is preferably 3N or more, more preferably 5N or more, and particularly preferably 6N or more.
- the content of P and B is preferably 0.5 ppm or less, more preferably 0.3 ppm or less, and particularly preferably 0.1 ppm or less with respect to the electrolytic bath. preferable.
- alkali metal elements and alkaline earth metal elements may not be considered as impurities in the electrolytic bath.
- these elements are less likely to move to the cathode than silicon and germanium, and hardly enter the cathode alloy.
- the metal used as the cathode solvent metal need not be considered as an impurity in the electrolytic bath.
- the higher specific gravity of the cathode and the electrolytic bath is positioned relatively lower than the lower specific gravity, and the anode is disposed from the cathode.
- the anode and the cathode can be arranged at positions separated from each other in the electrolytic bath.
- the anode and the cathode are arranged in the electrolytic bath at positions separated from each other in the lateral direction, or the same arrangement as in the case of the aluminum three-layer electrolytic purification method, that is, the anode and the electrolytic bath.
- these three elements have higher specific gravity in the lower part in the order of the cathode, the electrolytic bath, and the anode from the upper side, or in the order of the anode, the electrolytic bath, and the cathode from the upper side.
- the anode and the cathode are disposed at positions apart from each other in the electrolytic cell, and the anode and the cathode act via an electrolytic bath in the electrolysis process.
- the electrolysis temperature is set according to the composition of the cathode alloy so that the cathode alloy is maintained in a liquid phase.
- This electrolysis temperature is preferably higher than the complete solidification temperature of the cathode alloy.
- the electrolysis temperature is preferably lower than the melting point of the element to be purified. When the electrolysis temperature is lower than the melting point of the element to be purified, the current efficiency of electrolysis is further improved and the selection of the electrolytic cell material is facilitated.
- the complete solidification temperature of the alloy that is, the eutectic point is 577 ° C., so that the electrolysis temperature is higher than 577 ° C. It is preferable to set the temperature lower than the melting point of 1410 ° C.
- the complete solidification temperature of the alloy that is, the eutectic point is 398 ° C., so the electrolysis temperature is higher than 398 ° C. It is preferable to set the temperature lower than the melting point of 958 ° C.
- the electrolysis temperature is preferably as high as possible below the melting point of the element to be purified.
- the electrolysis temperature is preferably 700 ° C. or higher, more preferably 900 ° C. or higher, and particularly preferably 1100 ° C. or higher.
- the electrolysis temperature is preferably 1300 ° C. or lower in consideration of restrictions on the material of the electrolytic cell.
- the electrolysis temperature is preferably 500 ° C. or higher, more preferably 600 ° C. or higher, and particularly preferably 700 ° C. or higher.
- the electrolysis temperature is preferably 900 ° C. or lower in consideration of restrictions on the material of the electrolytic cell.
- the element to be purified is silicon and the electrolysis process is started using aluminum as the cathode solvent metal and pure aluminum as the cathode
- the melting point of aluminum is 660 ° C.
- the eutectic point of Al—Si is 580 ° C. Since it is about 0 ° C., first, the electrolytic reaction is started at 660 ° C. or higher at which the aluminum serving as the cathode becomes a liquid phase.
- silicon moves to the cathode and Al—Si is generated at the cathode.
- This alloy can be in a liquid phase above the eutectic point, and the electrolysis temperature can be lowered to 580 ° C. thereafter. Is possible. However, at temperatures below the eutectic point, solids precipitate and cause silicon dendritic growth.
- the element to be purified is germanium and the electrolysis process is started using zinc as the cathode solvent metal and pure zinc as the cathode
- the melting point of zinc is 419 ° C.
- the eutectic point of Zn—Ge is 398 Since it is about 0 ° C.
- the electrolytic reaction is started at 419 ° C. or higher where zinc as a cathode becomes a liquid phase.
- germanium moves to the cathode and Zn—Ge is formed on the cathode.
- This alloy can be in a liquid phase above the eutectic point, so that the electrolysis temperature can be lowered to 398 ° C. thereafter. Is possible.
- solids precipitate and cause germanium dendritic growth.
- the atmosphere of the electrolysis process is not particularly limited, but air or inert gas is preferable, and water, oxygen, etc. are more preferable for the progress of electrolysis.
- purified and the thing which does not react with an electrolytic bath are preferable,
- carbonized_material, a carbonaceous material etc. are mentioned.
- oxides include silica, alumina, zirconia, titania, zinc oxide, magnesia, tin oxide, etc.
- nitrides include silicon nitride, aluminum nitride, and the like. This includes elements that are partially substituted with other elements.
- a compound such as sialon containing silicon, aluminum, oxygen, and nitrogen can be used.
- the carbide include SiC
- examples of the carbonaceous material include graphite.
- a material obtained by partially replacing these constituent elements with other elements can also be used.
- a method of holding an electrolytic bath with a solidified electrolyte for example, cryolite may be used similarly to aluminum electrolysis. The same applies to the case where the element to be purified is germanium.
- the taking-out method is not particularly limited, and it may be taken out in a batch manner or in a continuous manner.
- the cathode alloy extracted from the electrolytic cell is cooled at a temperature higher than the complete solidification temperature and lower than the electrolysis temperature, and the element to be purified contained in the extracted alloy is precipitated as a solid.
- the cooling temperature is equal to or lower than the complete solidification temperature of the cathode alloy
- the solvent metal other than the element to be purified that is, the cathode solvent metal also precipitates together with the element to be purified. It becomes difficult to collect selectively.
- the cooling temperature is higher than the complete solidification temperature of the cathode alloy, and the concentration of the element to be purified in the cathode alloy taken out from the electrolytic cell is a composition corresponding to the complete solidification temperature of the alloy. Therefore, the element to be purified can be selectively deposited from the cathode alloy by cooling at this cooling temperature lower than the electrolysis temperature and higher than the complete solidification temperature.
- the upper limit of the cooling temperature is the electrolysis temperature.
- the amount of the element to be purified that can be recovered corresponds to the compositional difference of the liquidus of the alloy corresponding to the difference between the electrolysis temperature and the cooling temperature. Therefore, in order to increase the amount of the element to be purified that can be recovered, it is preferable that the temperature difference between the electrolysis temperature and the cooling temperature is large.
- the temperature difference between the electrolysis temperature and the cooling temperature is preferably 100 ° C. or higher, more preferably 200 ° C. or higher, even more preferably 300 ° C. or higher, regardless of whether the element to be purified is silicon or germanium.
- the temperature difference between the electrolysis temperature and the cooling temperature may not be large and can be used. Cooling can be performed at an economically optimal temperature difference in a wide temperature range.
- the cooling temperature can be lowered to the vicinity of the complete solidification temperature (eg, eutectic point) of the cathode alloy, it is preferable that the cooling temperature is equal to or higher than the melting point of the cathode solvent metal from the viewpoint of easy cooling operation.
- the element to be purified is silicon and an aluminum-silicon alloy is used as the cathode alloy
- the cathode is in the liquid phase until the silicon concentration in the cathode alloy reaches about 55% by mass at maximum. Can keep the state.
- this alloy is taken out of the electrolytic cell and cooled to 600 ° C., the silicon concentration does not reach equilibrium unless the silicon concentration is reduced to 15% by mass, so that silicon corresponding to 40% by mass of this difference can be recovered as a solid.
- the electrolysis temperature is 800 ° C.
- the cathode is in the liquid phase until the germanium concentration in the cathode alloy reaches a maximum of about 60% by mass. Can keep the state.
- this alloy is taken out of the electrolytic cell and cooled to 450 ° C., the germanium concentration does not reach equilibrium unless it is reduced to 12% by mass, so that germanium corresponding to 48% by mass of this difference can be recovered as a solid.
- a known method can be used as a method for cooling the cathode alloy. That is, a method of holding a cathode alloy taken out in a container kept at a cooling temperature, a cathode holding a cathode taken out in a container slightly higher than the cooling temperature, and a cooling body in which the cooling temperature is set in the cathode alloy And the like, and a method for precipitating the element to be purified on the surface of the cooling body.
- the solid precipitate of the element to be purified is recovered from the alloy of the cathode cooled in the precipitation step.
- the recovery method is not particularly limited, and examples thereof include filtration and centrifugation.
- a refined metal element or metalloid element that is, an element to be refined
- the element to be purified selectively moves from the bath and accumulates in the alloy of the cathode.
- the cathode alloy in which the concentration of the element to be purified is increased and is in the liquid phase is taken out from the electrolytic cell, and the element to be purified is selectively precipitated with high purity in the precipitation process, and is deposited from the cathode alloy in the recovery process.
- the refined element to be purified is recovered.
- an alloy containing the element to be purified and a solvent metal and having a complete solidification temperature lower than the melting point of the element to be purified is used as the cathode.
- the electrolysis temperature can be lowered as compared with the case where a simple substance is used as the liquid phase cathode. For this reason, it becomes possible to perform electrolysis at a temperature lower than the melting point of the element to be purified, and the energy load and the load on the material of the electrolytic cell are reduced as compared with the case where the element to be purified is used as a cathode. Can be advantageous.
- the cathode since the cathode is in a liquid phase, a stable electrode interface is formed, and when obtaining an alloy with a higher concentration of the element to be purified than that of the composition corresponding to the complete solidification temperature, the element to be purified is dendritic. Growth and short-circuiting between electrodes are suppressed, and entrainment of the electrolytic bath in the product of the element to be purified is suppressed.
- the concentration of the element to be purified in the alloy of the cathode that is brought into the precipitation process through the electrolytic process and the extraction process is that of the composition corresponding to the complete solidification temperature.
- the element to be purified contained in the cathode can be selectively deposited with high purity by cooling.
- the residue after recovering the element to be purified deposited from the cooled cathode alloy is returned to the cathode of the electrolysis process, so that the alloy whose concentration of the element to be purified is sufficiently reduced is used again as the cathode. It is possible to move the element to be purified from the anode material to the cathode and increase the concentration efficiently and continuously. Therefore, in the electrolysis step, the purification can be continuously performed as long as the fluidity of the cathode alloy can be maintained without the electrolysis stagnation because the element to be purified reaches a saturated concentration.
- the anode is preferably an alloy that becomes a liquid phase at the electrolysis temperature. This makes it easy to appropriately add a material that becomes the anode into the electrolytic bath, and makes the electrolysis process more continuous.
- the element to be purified is silicon
- an amount of more than 40% by mass with respect to the cathode (including aluminum as the cathode solvent metal and pure aluminum as the cathode at the start of the electrolysis process) in the electrolysis process Silicon can be obtained, for example, 45% by mass or more of silicon can be obtained in the recovery step.
- the element to be purified is germanium
- a larger amount of germanium than 40% by mass with respect to the cathode in the electrolysis process including the case where zinc is used as the cathode solvent metal and pure zinc is used as the cathode at the start of the electrolysis process.
- production is controlled by current.
- the recovery of the element to be purified obtained as described above is much higher purity than the material of the anode used as a raw material, and is suitable as a raw material for silicon for solar cells in the case of electronic devices and sputter targets, particularly silicon. Used for.
- the recovered material to be refined is treated with acid or alkali to remove the residue of metal components and unreacted metal components, segregation such as directional solidification, and dissolution under high vacuum. Etc., the impurity elements contained in the recovered product of the element to be purified can be further reduced.
- the obtained polycrystalline silicon is highly purified by directional solidification.
- An ingot is produced by the casting method or electromagnetic casting method using the silicon obtained in the present invention.
- the conductivity type of the substrate of the solar cell is generally p-type.
- p-type silicon can be obtained by introducing dopant into silicon by adding boron to silicon or leaving aluminum to remain during silicon purification.
- the ingot is sliced by cutting an inner peripheral blade or using a multi-wire saw. After slicing, both sides of the slice are lapped using loose abrasives as necessary, and the ingot slice wrapped in an etching solution such as hydrofluoric acid is immersed in order to remove the damaged layer.
- a crystalline silicon substrate is obtained.
- a V-groove was mechanically formed on the surface using a dicing machine, reactive ion etching, acid, alkali, or the like was used.
- a texture structure is formed by etching.
- a pn junction is obtained by forming a diffusion layer of n-type dopant such as phosphorus or arsenic on the light receiving surface of the polycrystalline silicon substrate.
- an oxide film layer such as TiO 2
- a solar cell is fabricated by attaching an electrode to each layer and attaching an antireflection film such as MgF 2 to reduce the loss of light energy due to reflection. can do.
- Example 1 A graphite crucible is charged with aluminum, cryolite, and silica and set in an electric furnace having a mullite core tube. Next, at 1100 ° C., solid silicon containing impurities is immersed in a bath, and this solid silicon is electrolyzed using the anode and the liquid phase aluminum on the bottom of the graphite crucible as the cathode.
- purified silicon can be obtained by dissolving the resulting alloy with hydrochloric acid. Moreover, the cathode alloy after electrolysis is taken out as it is at 1100 ° C., kept at 700 ° C. for 3 hours to be partially precipitated, and solid-liquid separation is performed, so that a relatively high silicon concentration and a relatively high silicon concentration are obtained. With a low melt, purified silicon can be obtained. The melt (residue) after separating the precipitate (purified silicon) can be returned again into the graphite crucible of the electrolytic furnace to perform electrolytic purification of silicon.
- Example 2 A magnesia crucible is charged with an alloy of copper and silicon, cryolite, silica, calcium chloride, barium chloride, an alloy of aluminum and silicon, and this is set in an electric furnace having a mullite core tube. Next, electrolysis is performed at 1100 ° C. using an alloy of copper and silicon as an anode and an alloy of aluminum and silicon as a cathode. After the electrolysis, the cathode alloy is recovered by cooling. Purified silicon can be obtained by dissolving the obtained cathode alloy with hydrochloric acid. In addition, the electrolyzed alloy is taken out at 1100 ° C., kept at 700 ° C.
- purified silicon can be obtained.
- the melt (residue) after separating the precipitate (purified silicon) can be returned again into the magnesia crucible of the electrolytic furnace, and the silicon can be subjected to electrolytic purification.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Inorganic Chemistry (AREA)
- Electrolytic Production Of Metals (AREA)
- Silicon Compounds (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
Description
合金の完全凝固温度とは、合金の固液状態図における液相線の最小値に対応する温度であり、完全凝固温度未満では該合金は液相を含むことができない。
溶媒金属が金属元素又は半金属元素との固溶体を実質的に作らない、とは、完全凝固温度における金属元素又は半金属元素に対する溶媒金属の固溶限が1質量%以下であることを意味する。
本発明では、金属元素又は半金属元素(以下、精製対象元素と呼ぶことがある。)を精製の対象とする。精製対象元素は特に限定されない。金属元素としては、ベリリウム等のアルカリ土類金属、スカンジウム、チタン、ニッケル等の第1遷移元素、ジルコニウム、イットリウム等の第2遷移元素、ランタン、ネオジム、イウロピウム、ジスプロシウム、レニウム、サマリウム等のランタノイド、トリウム、ウラン、プルトニウム、アメリシウム等のアクチノイド、白金、等の第3遷移元素が挙げられる。
電解工程では、電解槽内に設置された電解浴中において、精製対象元素、及び、不純物を含む材料を陽極として、かつ、前記陽極に含まれる精製対象元素と同種の精製対象元素と溶媒金属を含有しこの精製対象元素の融点よりも低い完全凝固温度(詳しくは後述)を有する合金を陰極として作用させ、陰極の合金が液相となることができる電解温度で電解を行って陽極中の精製対象元素を陰極の合金中に移動させ、精製対象元素の濃度が、完全凝固温度(詳しくは後述)に対応する合金組成における精製対象元素の濃度よりも高い合金を陰極に得る。
陽極の材料は、精製対象元素、及び、不純物を含む材料であり、精製の原材料という側面を持つ。陽極の材料は電解温度で固相であるものでも良いが、電解反応のし易さから、電解温度において液相となるものが好ましい。
MFx(solid)→M(solid)+x/2F2(gas)
Siの場合、理論分解電圧は、次式の反応が進行すると仮定して計算されている。活量はいずれも1、温度は1000℃である。
SiF4(gas)→Si(solid)+2F2(gas)
陰極としては、前記陽極に含まれる精製対象元素と同種の精製対象元素、及び、精製対象元素とは異なる溶媒金属(以下、陰極溶媒金属と呼ぶことがある)を含有し、精製対象元素の融点よりも低い完全凝固温度を有する合金が用いられる。陰極溶媒金属は、精製対象元素との固溶体を実質的に作らない。
合金の完全凝固温度とは、合金の固液状態図における液相線の最小値に対応する温度であり、完全凝固温度未満では該合金は液相を含むことができない。
陰極溶媒金属が、精製対象元素との固溶体を実質的に作らないとは、完全凝固温度における精製対象元素に対する陰極溶媒金属の固溶限が1質量%以下であることを意味する。
陰極溶媒金属は、精製対象元素との共融点を有してもよい。すなわち、陰極溶媒金属と精製対象金属との合金は、前記液相線に極小値を有してもよい。
また、この合金は、蒸気圧が低く、安定であることが好ましい。
例えば、精製対象元素がGeであり陰極溶媒金属がPbである、ゲルマニウム-鉛系の固液状態図は図1のようになり、この系の完全凝固温度は、液相線Aの最小値となる点Bである327℃である。この合金における完全凝固温度に対応するGe(精製対象元素)の濃度は0wt%である。
また、精製対象元素がSiであり陰極溶媒金属がAlである、シリコン-アルミニウム系の固液状態図は図2のようになる。この系の完全凝固温度は、液相線Aの最小値(極小値)を示す点Cである577℃となり、この点Cのように液相線が極小値をとる点は共融点と呼ばれる。この合金の完全凝固温度に対応する組成のSi濃度は、約12.6wt%となり、この組成は共融点に対応する組成であり共融組成とも呼ばれる。なお、シリコン-銀系、ゲルマニウム-亜鉛系等の合金系でも、図2と同様の共融点を有する状態図を示す。
共融点を有する合金では、取出し時の精製対象元素の濃度が、共融点に対応する組成のそれよりも高い必要がある。言い換えると、例えば、図2において、取出し時の合金中の精製対象元素であるSiの濃度が、共融組成のそれである12.6wt%を超える必要がある。また、特に効率よく精製対象元素を回収するには、定められた電解温度において、陰極の合金が液相の単相として存在できる最大の精製対象元素の濃度である、精製対象元素の飽和濃度に近くなるまで、陰極の合金における精製対象元素の濃度を電解により高濃度化することが好ましい。
電解浴は、精製対象元素のイオンを伝導できるものであれば特に限定されないが、金属のハロゲン化物が好ましい。金属のハロゲン化物を構成する金属元素として、アルカリ金属、アルカリ土類金属、アルミニウム、亜鉛、及び、銅から選択される1種以上の元素が挙げられる。また、金属のハロゲン化物を構成するハロゲンとして、フッ素、塩素、及び、臭素からなる群から選択される1種以上の元素が挙げられる。また、これらの金属のハロゲン化物を2種以上混合して用いてもよい。金属のハロゲン化物の混合物の例としては、フッ化ナトリウムとフッ化アルミニウムの混合物が挙げられる。電解浴として、より具体的には、工業的な入手のしやすさから、氷晶石(3NaF・AlF3)、塩化カルシウムなどが好ましい。なお、これらの電解浴は、溶融された状態で用いられる。
電解温度は陰極の合金の組成に応じて、この陰極の合金が液相に維持されるように設定される。この電解温度は、陰極の合金の完全凝固温度より高いことが好ましい。電解温度が高いほど、陰極の合金中の精製対象元素の溶解度が向上するので、より多くの精製対象元素を陰極に移動させ、これを回収することが可能になる。電解温度は、精製対象元素の融点より低いことが好ましい。電解温度が精製対象元素の融点未満であれば、電解の電流効率がより向上し、また、電解槽材料の選定が容易となる。
精製対象元素がシリコンである場合、電解温度は700℃以上が好ましく、900℃以上がさらに好ましく、1100℃以上が特に好ましい。ただし、電解槽の材料の制約などを考慮し、電解温度は1300℃以下が好ましい。
精製対象元素がゲルマニウムである場合は、電解温度は500℃以上が好ましく、600℃以上がさらに好ましく、700℃以上が特に好ましい。ただし、電解槽の材料の制約などを考慮し、電解温度は900℃以下が好ましい。
電解浴を収容する電解槽の材質は特に限定されないが、精製対象元素、及び、電解浴と反応しないものが好ましく、例えば、酸化物、窒化物、炭化物、炭素質材料等が挙げられる。精製対象元素がシリコンの場合、例えば酸化物としてはシリカ、アルミナ、ジルコニア、チタニア、酸化亜鉛、マグネシア、酸化スズ等が挙げられ、窒化物としては、窒化珪素、窒化アルミニウムが挙げられ、これらの構成元素を他元素で部分置換したものも含まれる。例えば、シリコン、アルミニウム、酸素および窒素を含むサイアロン等の化合物を用いることもできる。炭化物としては、SiC等が挙げられ、炭素質材料としてはグラファイト等が挙げられ、これらの構成元素を他元素で部分置換したものを用いることもできる。さらにアルミニウム電解などと同様に、固化した電解質(例えば氷晶石)で電解浴を保持する方法を用いてもよい。
精製対象元素がゲルマニウムの場合も上記と同様である。
取出工程では、上述のようにして電解がなされた陰極の合金の一部または全部を電解槽外に取り出す。取出し方法は特に限定されず、バッチ式で取り出してもよいし、連続式に取り出してもよい。
析出工程では、電解槽から取出した陰極の合金を、前記完全凝固温度より高く、かつ、前記電解温度よりも低い温度で冷却して、前記取出した合金中に含まれる精製対象元素を固体として析出させる。
例えば、精製対象元素がゲルマニウムであり、陰極の合金として亜鉛-ゲルマニウム合金を用いる場合、電解温度を800℃とすると、陰極の合金中においてゲルマニウム濃度は最大60質量%程度となるまで陰極が液相状態を保つことができる。この合金を電解槽外に取り出して450℃に冷却するとゲルマニウム濃度は12質量%まで低下しなければ平衡にならないので、この差の48質量%に相当するゲルマニウムが固体として回収できる。
回収工程では、析出工程で冷却された陰極の合金から、精製対象元素の固体析出物を回収する。回収方法は特に限定されないが、ろ過、遠心分離等が挙げられる。
再利用工程では、回収工程にて、陰極の合金から析出された精製対象元素を回収した後の残渣を、前記電解工程の陰極として用いる。
黒鉛坩堝に、アルミニウム、氷晶石、シリカを仕込み、これを、ムライト炉心管をもつ電気炉中にセットする。次に1100℃で、不純物を含む固体シリコンを浴中に浸漬し、この固体シリコンを陽極、黒鉛るつぼの底面の液相のアルミニウムを陰極として電解する。
マグネシアるつぼに、銅とシリコンの合金、氷晶石、シリカ、塩化カルシウム、塩化バリウム、アルミニウムとシリコンの合金を仕込み、これを、ムライト炉心管をもつ電気炉中にセットする。次に1100℃で、銅とシリコンの合金を陽極、アルミニウムとシリコンの合金を陰極として電解する。
電解後、冷却して陰極の合金を回収する。得られる陰極の合金を塩酸で溶解することにより、精製されたシリコンを得ることができる。また、電解後の合金を1100℃のまま取り出し、700℃で3時間保持して一部析出させ、固液分離することにより、相対的にシリコン濃度が高い析出物と相対的にシリコン濃度が低い融液とを得て、精製されたシリコンを得ることができる。析出物(精製されたシリコン)を分離した後の融液(残渣)を再度電解炉のマグネシア坩堝内に戻してシリコンの電解精製を行うことができる。
Claims (8)
- 精製された金属又は半金属の製造方法であって、
電解槽内に設置された電解浴中において、金属元素又は半金属元素、及び、不純物を含む材料を陽極として、前記陽極に含まれる前記金属元素又は半金属元素と同種の金属元素又は半金属元素と、前記金属元素又は半金属元素との固溶体を実質的に作らない溶媒金属とを含有し、前記金属元素又は半金属元素の融点よりも低い完全凝固温度を有する合金を陰極として作用させ、前記合金が液相となることができる電解温度で電解を行うことにより、前記陽極中の前記金属元素又は半金属元素を前記陰極の合金中に移動させる電解工程と、
前記電解工程の後に、前記陰極の合金の一部または全部を電解槽外に取り出す取出工程と、
前記完全凝固温度より高く、かつ、前記電解温度より低い温度で、前記の取出した合金を冷却することにより前記合金中に含まれる前記金属元素又は半金属元素を析出させる析出工程と、
前記の冷却された合金から前記析出された前記金属元素又は半金属元素を回収する回収工程と、を備える方法。 - 前記溶媒金属は、前記金属元素又は半金属元素との共融点を有する請求項1記載の方法。
- 前記の冷却された合金から前記析出された前記金属元素又は半金属元素を回収した後の残渣を前記電解工程の陰極として用いる再利用工程をさらに備える請求項1又は2記載の方法。
- 前記金属元素又は半金属元素は、シリコン又はゲルマニウムである請求項1~3のいずれか一項記載の方法。
- 前記陰極の合金は、アルミニウム、銀、銅、及び、亜鉛からなる群から選択された1種以上の金属元素を含む請求項4記載の方法。
- 前記陽極の材料は、銀、銅、スズ、及び、鉛からなる群から選択された1種以上の金属元素を含む請求項4又は5記載の方法。
- 前記電解浴が、氷晶石を含む請求項1~6の何れか一項記載の方法。
- 前記電解温度が、前記完全凝固温度より高く、かつ、前記金属元素又は半金属元素の前記融点より低い、請求項1~7の何れか一項記載の方法。
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/322,535 US20120132034A1 (en) | 2009-05-26 | 2010-05-24 | Process for producing refined metal or metalloid |
DE112010004425T DE112010004425T5 (de) | 2009-05-26 | 2010-05-24 | Verfahren zur Herstellung von gereinigtem Metall oder Halbmetall |
CN2010800230624A CN102449201A (zh) | 2009-05-26 | 2010-05-24 | 精炼的金属或准金属的制造方法 |
CA2762941A CA2762941A1 (en) | 2009-05-26 | 2010-05-24 | Process for producing refined metal or metalloid |
NO20111662A NO20111662A1 (no) | 2009-05-26 | 2011-12-01 | Fremgangsmate for fremstilling av raffinert metall eller metalloid |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2009-126942 | 2009-05-26 | ||
JP2009126942 | 2009-05-26 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2010137555A1 true WO2010137555A1 (ja) | 2010-12-02 |
Family
ID=43222664
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2010/058739 WO2010137555A1 (ja) | 2009-05-26 | 2010-05-24 | 精製された金属又は半金属の製造方法 |
Country Status (7)
Country | Link |
---|---|
US (1) | US20120132034A1 (ja) |
JP (1) | JP2011006317A (ja) |
CN (1) | CN102449201A (ja) |
CA (1) | CA2762941A1 (ja) |
DE (1) | DE112010004425T5 (ja) |
NO (1) | NO20111662A1 (ja) |
WO (1) | WO2010137555A1 (ja) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20150259808A1 (en) * | 2012-11-28 | 2015-09-17 | Trustees Of Boston University | Method and apparatus for producing solar grade silicon using a som electrolysis process |
CN115305514A (zh) * | 2021-05-08 | 2022-11-08 | 中南大学 | 一种熔盐电解精炼铪的方法 |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP5814585B2 (ja) * | 2011-04-01 | 2015-11-17 | 株式会社東芝 | 希土類金属の回収方法および回収装置 |
CA2863158C (en) | 2012-01-17 | 2021-02-02 | Suntory Holdings Limited | Glycosyltransferase gene and use thereof |
JP5944237B2 (ja) * | 2012-06-15 | 2016-07-05 | 株式会社東芝 | 核燃料物質の回収方法 |
CN103243385B (zh) * | 2013-05-13 | 2016-04-27 | 北京科技大学 | 电解精炼-液态阴极原位定向凝固制备高纯单晶硅的方法 |
KR101509086B1 (ko) | 2013-10-01 | 2015-04-07 | 한국에너지기술연구원 | 태양전지의 금속회수방법 |
KR101584172B1 (ko) * | 2013-10-01 | 2016-02-19 | 한국에너지기술연구원 | 태양전지의 금속회수방법 |
KR101852019B1 (ko) | 2017-03-10 | 2018-04-26 | 세일정기 (주) | 고순도 탄화규소의 제조방법 |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5589440A (en) * | 1978-12-26 | 1980-07-07 | Aluminum Co Of America | Aluminum refining method |
JPS61159593A (ja) * | 1984-12-07 | 1986-07-19 | ロ−ヌ−プ−ラン・スベシアリテ・シミ−ク | 希土類若しくはその合金の電解製造方法及びこの方法を物施する装置 |
JP2006083426A (ja) * | 2004-09-15 | 2006-03-30 | Dowa Mining Co Ltd | ガリウム中のゲルマニウム除去方法及びこの方法によって得たガリウム並びにゲルマニウム除去装置 |
WO2007106709A2 (en) * | 2006-03-10 | 2007-09-20 | Elkem As | Method for electrolytic production and refining of metals |
WO2008115072A2 (en) * | 2007-03-21 | 2008-09-25 | Sinvent As | Electrolyte and method for electrochemical refining of silicon |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL290209A (ja) * | 1962-03-14 | |||
US8303796B2 (en) * | 2006-05-26 | 2012-11-06 | Sumitomo Chemical Company, Limited | Method for producing silicon |
-
2010
- 2010-05-24 CA CA2762941A patent/CA2762941A1/en not_active Abandoned
- 2010-05-24 CN CN2010800230624A patent/CN102449201A/zh active Pending
- 2010-05-24 US US13/322,535 patent/US20120132034A1/en not_active Abandoned
- 2010-05-24 WO PCT/JP2010/058739 patent/WO2010137555A1/ja active Application Filing
- 2010-05-24 JP JP2010118492A patent/JP2011006317A/ja active Pending
- 2010-05-24 DE DE112010004425T patent/DE112010004425T5/de not_active Withdrawn
-
2011
- 2011-12-01 NO NO20111662A patent/NO20111662A1/no not_active Application Discontinuation
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5589440A (en) * | 1978-12-26 | 1980-07-07 | Aluminum Co Of America | Aluminum refining method |
JPS61159593A (ja) * | 1984-12-07 | 1986-07-19 | ロ−ヌ−プ−ラン・スベシアリテ・シミ−ク | 希土類若しくはその合金の電解製造方法及びこの方法を物施する装置 |
JP2006083426A (ja) * | 2004-09-15 | 2006-03-30 | Dowa Mining Co Ltd | ガリウム中のゲルマニウム除去方法及びこの方法によって得たガリウム並びにゲルマニウム除去装置 |
WO2007106709A2 (en) * | 2006-03-10 | 2007-09-20 | Elkem As | Method for electrolytic production and refining of metals |
WO2008115072A2 (en) * | 2007-03-21 | 2008-09-25 | Sinvent As | Electrolyte and method for electrochemical refining of silicon |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20150259808A1 (en) * | 2012-11-28 | 2015-09-17 | Trustees Of Boston University | Method and apparatus for producing solar grade silicon using a som electrolysis process |
US10266951B2 (en) * | 2012-11-28 | 2019-04-23 | Trustees Of Boston University | Method and apparatus for producing solar grade silicon using a SOM electrolysis process |
CN115305514A (zh) * | 2021-05-08 | 2022-11-08 | 中南大学 | 一种熔盐电解精炼铪的方法 |
CN115305514B (zh) * | 2021-05-08 | 2023-11-17 | 中南大学 | 一种熔盐电解精炼铪的方法 |
Also Published As
Publication number | Publication date |
---|---|
DE112010004425T5 (de) | 2012-11-29 |
US20120132034A1 (en) | 2012-05-31 |
NO20111662A1 (no) | 2011-11-28 |
CN102449201A (zh) | 2012-05-09 |
CA2762941A1 (en) | 2010-12-02 |
JP2011006317A (ja) | 2011-01-13 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO2010137555A1 (ja) | 精製された金属又は半金属の製造方法 | |
US8303796B2 (en) | Method for producing silicon | |
JP5445725B1 (ja) | Al−Sc合金の製造方法 | |
CN108138343B (zh) | 利用电解还原和电解精炼工序的金属精炼方法 | |
KR101163375B1 (ko) | 원광 금속환원 및 전해정련 일관공정에 의한 원자로급 지르코늄 친환경 신 제련공정 | |
CA2645161C (en) | Method for electrolytic production and refining of metals | |
EP3368477A1 (en) | Method for the enrichment and separation of silicon crystals from a molten metal for the purification of silicon | |
CN102851679B (zh) | 一种熔盐电解去除硅中硼和磷杂质的方法 | |
KR101878652B1 (ko) | 전해환원 및 전해정련 일관공정에 의한 금속 정련 방법 | |
WO2008156372A2 (en) | Method for recovering elemental silicon from cutting remains | |
US20230392273A1 (en) | Method for manufacturing recycled aluminum, manufacturing equipment, manufacturing system, recycled aluminum, and processed aluminum product | |
JP7486199B2 (ja) | 反応性金属の電解生成 | |
JP5236897B2 (ja) | シリコンの製造方法 | |
JP6318049B2 (ja) | 高純度In及びその製造方法 | |
Oishi et al. | Electrorefining of silicon using molten salt and liquid alloy electrodes | |
Delannoy et al. | 3 Conventional and Advanced Purification Processes of MG Silicon | |
JP5829843B2 (ja) | 多結晶シリコンの製造方法及び多結晶シリコンの製造方法に用いられる還元・電解炉 | |
JP7403118B2 (ja) | 金属の回収方法及び窒化ガリウムの製造方法 | |
JP2014502671A (ja) | シリコンの製造方法および器具 | |
Delannoy et al. | 3 Conventional and | |
CN103261095A (zh) | 用于制造硅的方法和装置 | |
WO2008115072A2 (en) | Electrolyte and method for electrochemical refining of silicon |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 201080023062.4 Country of ref document: CN |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 10780510 Country of ref document: EP Kind code of ref document: A1 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2762941 Country of ref document: CA |
|
WWE | Wipo information: entry into national phase |
Ref document number: 1120100044252 Country of ref document: DE Ref document number: 112010004425 Country of ref document: DE |
|
WWE | Wipo information: entry into national phase |
Ref document number: 13322535 Country of ref document: US |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 10780510 Country of ref document: EP Kind code of ref document: A1 |