WO2015060026A1

WO2015060026A1 - Method for manufacturing high purity manganese and high purity manganese

Info

Publication number: WO2015060026A1
Application number: PCT/JP2014/073615
Authority: WO
Inventors: 和人八木
Original assignee: Jx日鉱日石金属株式会社
Priority date: 2013-10-25
Filing date: 2014-09-08
Publication date: 2015-04-30
Also published as: JPWO2015060026A1; KR20150125721A; KR101678334B1; US20160032427A1; JP6050485B2; TW201527541A; KR20160125537A

Abstract

The present invention relates to a method for manufacturing high purity Mn, the method being characterized in that: a Mn starting material is placed in a magnesia crucible and is melted at a melting temperature of 1240-1400°C using a vacuum induction melting furnace (VIM furnace) under an inert atmosphere of 500 Torr or less; calcium is added in a range of 0.5-2.0% of the Mn weight to perform de-oxygenation and de-sulfurization; after completion of the de-oxygenation and de-sulfurization, an ingot is manufactured by pouring into an iron mold; then said Mn ingot is loaded in a scull melting furnace, the pressure is reduced to 10^-5 Torr or less using a vacuum pump, and heating is started; and after the melted state is maintained for 10-60 minutes, the melting reaction is completed to obtain high purity Mn. The present invention provides a method for manufacturing high purity metal Mn from commercially available electrolytic Mn. In particular, the present invention addresses the problem of obtaining high purity metal Mn with low amounts of impurities such as B, Mg, Al and Si.

Description

Method for producing high purity manganese and high purity manganese

The present invention relates to high-purity manganese (Mn) from commercially available electrolytic manganese (Mn) and a method for producing the same.

A commercially available method for producing metal Mn is an electrolytic method from an ammonium sulfate electrolytic bath. In the commercially available electrolytic Mn obtained by this method, sulfur (S) is about 100 to 3000 ppm, and carbon (C) is also several hundred ppm. include. Chlorine (Cl) is also several hundred ppm, and oxygen (O) is contained in the order of several thousand ppm because it is an electrodeposit from the aqueous solution.

As a method for removing S and O from the electrolytic Mn, a sublimation purification method is well known in the prior art. However, the sublimation purification method has a problem that the apparatus is very expensive and the yield is very bad. In addition, even if S and O can be reduced by the sublimation purification method, it is contaminated due to the heater material, condenser material, etc. of the sublimation purification device, so metal Mn by the purification method is used as a raw material for electronic devices. There was a problem that it was not suitable.

As a prior art, a method for removing S in metal Mn is described in Patent Document 1 below, and Mn oxidation is performed at a melting temperature of Mn acid compounds such as MnO, Mn ₃ O ₄ , MnO ₂ and / or metal Mn. For example, Mn carbonate or the like is added, and the metal Mn to which the Mn compound is added is melted in an inert atmosphere and kept in a molten state, preferably for 30 to 60 minutes, and the S content: 0.002% It is described that.

However, this document 1 does not describe the contents of oxygen (O), nitrogen (N), carbon (C), and chlorine (Cl) at all, and has not yet solved the problems caused by the contents thereof. .

In Patent Document 2 below, a method for electrolytically collecting metal Mn and high-purity metal Mn are dissolved in hydrochloric acid, and an undissolved material is filtered. A method for electrolytic collection of metal Mn, characterized by using an electrolyte prepared by filtering a product and adding a buffer, preferably adding metal Mn to a hydrochloric acid solution of metal Mn, Using electrolyte prepared by adding hydrogen peroxide and aqueous ammonia to the solution obtained by filtering undissolved material, filtering the precipitate formed under weakly acidic or neutral liquidity, and adding a buffer. A method of performing electrowinning of metal Mn is described.

However, in this document 2, there is a description of S: 1 ppm reduction of high-purity Mn, but the contents of oxygen (O), nitrogen (N), carbon (C), chlorine (Cl) are not at all. There is no description and it has not led to the solution of the problems caused by the inclusion thereof.

The following Patent Document 3 describes a method for producing high-purity Mn. An ion-exchange purification method using a chelate resin is applied to an aqueous Mn chloride solution, and then the purified aqueous Mn chloride solution is purified by electrowinning. How to do is described. The dry method describes that high-purity Mn is obtained from solid-phase Mn by vacuum sublimation purification method (Mn vapor obtained by sublimation of solid-phase Mn is selectively condensed and vapor-deposited in the cooling section by vapor pressure difference). Has been.

The document 3 describes that the total concentration of sulfur (S), oxygen (O), nitrogen (N), and carbon (C) is 10 ppm or less.
However, this document 3 does not describe the content of chlorine (Cl) that is harmful to the manufacture of semiconductor components. Since Mn chloride is used as a raw material, there is a possibility that chlorine may be contained in a high concentration, which is problematic.

Patent Document 4 below describes a method for producing a low-oxygen Mn material, and obtains a Mn material in which the oxygen content is reduced to 100 ppm or less by inductively skull-dissolving the Mn raw material in an inert gas atmosphere. There is a description that it is preferable to perform acid cleaning before induction skull dissolution of the Mn raw material because oxygen can be further reduced. However, in this document 4, there is a description regarding the reduction of oxygen (O), sulfur (S), and nitrogen (N) in high-purity Mn, but there is no description regarding the content of other impurities. The problem of inclusion has not been solved.

Patent Document 5 below describes a Mn alloy material for magnetic materials, a Mn alloy sputtering target, and a magnetic thin film, and has an oxygen content of 500 ppm or less and an S content of 100 ppm or less, preferably further impurities (Mn and alloy components). It is described that the total content of elements other than the above is 1000 ppm or less.
Furthermore, the same literature describes a method for removing oxygen (O) and sulfur (S) by adding Ca, Mg, La, etc. as a deoxidizing / desulfurizing agent to commercially available electrolytic Mn, and performing high-frequency dissolution, It describes that it is purified by vacuum distillation after preliminary dissolution.

In the above Mn raw material, in Example 3, a deoxidizing / desulfurizing agent was added and high-frequency dissolution was performed to obtain an oxygen content of 50 ppm and a sulfur content of 10 ppm (Table 3 of Patent Document 5). There is a description that the oxygen content is 30 ppm and the sulfur content is 10 ppm (Table 7 of Patent Document 5) by distillation. In these examples, Si is contained in an amount of about 10 to 20 ppm and Pb is contained in an amount of about 10 to 30 ppm.

However, the purity of Mn produced from Patent Document 5 below is 3N level, and the high purity Mn obtained from the present invention is not obtained. Further, in Example 3 of Patent Document 5 below, since the deoxidation / desulfurization agent is added and dissolved at high frequency, there is a problem that the deoxidation / desulfurization agent is mixed in Mn and lowers the purity. Has been subjected to vacuum distillation after pre-dissolution and volatilizes 99% or more of the dissolved Mn, which has a problem of high production cost.

Patent Document 6 below describes a method for producing a high-purity Mn material and a high-purity Mn material for forming a thin film. In this case, it is described that a high-purity Mn material is obtained by pre-dissolving crude Mn at 1250-1500 ° C. and then vacuum distillation at 1100-1500 ° C. Preferably, the degree of vacuum during vacuum distillation 5 × ^{10 -} and 5 ~ 10 Torr.

The high-purity Mn thus obtained has a total impurity content of 100 ppm or less, oxygen (O): 200 ppm or less, nitrogen (N): 50 ppm or less, sulfur (S): 50 ppm or less, carbon (C): 100 ppm or less. . And Example 2 (Table 2) describes an example in which oxygen is 30 ppm and other elements are less than 10 ppm. However, also in this case, the impurity level does not reach the target level.

In addition, Patent Document 7 below describes a sputtering target made of a high-purity Mn alloy, Patent Document 8 describes a method of recovering Mn using sulfuric acid, and Patent Document 9 produces metal Mn by heat reduction of Mn oxide. However, there is no description regarding desulfurization.

From the above, the present inventors leached the Mn raw material with an acid, filtered the residue with a filter, and then used the filtered solution on the cathode side in electrolysis, and also removed the electrolytic Mn. A method for producing high-purity Mn having a Cl content of 100 ppm or less in the electrolytic Mn by gas treatment, and further by degassing the electrolytic Mn raw material and dissolving it in an inert atmosphere, Cl ≦ 10 ppm, C A high-purity Mn production method for producing Mn with ≦ 50 ppm, S <50 ppm, and O <30 ppm was proposed (see Patent Document 10).
This method is effective for increasing the purity of Mn. The present invention is aimed at a manufacturing method and high-purity Mn that can achieve higher purity and can reduce costs.

JP 53-8309 A JP 2007-119854 A JP 2002-285373 A JP 2002-167630 A Japanese Patent Application Laid-Open No. 11-100651 Japanese Patent Laid-Open No. 11-152528 JP 2011-068992 A JP 2010-209384 A JP 2011-094207 A JP2013-142184A

An object of the present invention is to provide a high-purity Mn from a commercially available electrolytic Mn and a method for producing the same, and in particular, to produce a high-purity Mn with a lower amount of impurities and at a lower cost than the prior art. Let it be an issue.

The present invention solves the above problems and provides the following inventions.
1) A method for producing high-purity Mn, in which a Mn raw material is placed in a magnetic crucible and melted at a melting temperature of 1240 to 1400 ° C. in an inert atmosphere of 500 Torr or less using a vacuum induction melting furnace (VIM furnace). Calcium (Ca) is added in the range of 0.5 to 2.0% of the Mn weight to perform deoxidation and desulfurization, and after completion of the deoxidation and desulfurization, an ingot is produced by casting into an iron mold. A Mn ingot is loaded into a skull melting furnace, heated by reducing the pressure to 10 ⁻⁵ Torr or less with a vacuum pump, and after maintaining the molten state for 10 to 60 minutes, the melting reaction is terminated to obtain high purity Mn. A method for producing high-purity Mn.

2) High-purity Mn purified by vacuum induction melting (VIM) and skull melting, and the total amount of impurity elements B, Mg, Al, Si, S, Ca, Cr, Fe, Ni is 50 ppm or less, A high-purity Mn having a purity of 4N5 (99.995%) or more excluding gas component elements.

3) High-purity Mn purified by vacuum induction melting (VIM) and skull melting, and the total amount of impurity elements B, Mg, Al, Si, S, Ca, Cr, Fe, Ni is 50 ppm or less, A high-purity Mn having a purity of 4N5 (99.995%) or higher, excluding gas component elements, and oxygen (O) and nitrogen (N) as gas components being less than 10 ppm each.

4) The total amount of impurity elements B, Mg, Al, Si, S, Ca, Cr, Fe, and Ni is 50 ppm or less, and has a purity of 4N5 (99.995%) or more excluding gas component elements. High-purity Mn characterized by

5) The total amount of impurity elements B, Mg, Al, Si, S, Ca, Cr, Fe, and Ni is 50 ppm or less, and has a purity of 4N5 (99.995%) or more excluding gas component elements. High purity Mn, characterized in that oxygen (O) and nitrogen (N) as gas components are each less than 10 ppm.

The unit “ppm” used in this specification means “wtppm”. Except for nitrogen (N) and oxygen (O) which are gas component elements, analysis values of each element concentration are GDMS (Glow Discharge). The analysis was performed by Mass Spectrometry, and the gas component elements (O, N) were analyzed using an oxygen-nitrogen analyzer manufactured by LECO. In addition, the gas component element in the present invention means hydrogen (H), oxygen (O), nitrogen (N), and carbon (C). The following also means the same.

The present invention has the following effects.
(1) High-purity Mn having a total amount of impurity elements B, Mg, Al, Si, S, Ca, Cr, Fe, and Ni of 50 ppm or less and a purity of 4N5 (99.995%) or more; It is possible to obtain high-purity Mn in which O and N as gas components can each be less than 10 ppm.

(2) According to the present invention, it can be produced in a general-purpose furnace without requiring a special apparatus, and high purity Mn can be obtained at a low cost and in a high yield as compared with the conventional distillation method. The effect that it can do etc. can be mentioned.

(3) Moreover, when it is set as a sputtering target, it has the effect that it can be set as the target with few generation | occurrence | production of a particle.

It is a schematic explanatory drawing of a series of processes from a raw material Mn to manufacturing high-purity Mn through VIM dissolution and skull dissolution processes.

Hereinafter, embodiments of the present invention will be described in detail.
The method for producing high-purity Mn according to the present invention can use commercially available (2N level) flaky electrolytic Mn as a raw material, but since it does not affect the purity of the raw material, the type of the raw material is not particularly limited.

In producing high-purity Mn, first, a Mn raw material is put in a magnesia crucible and melted at a melting temperature of 1240 to 1400 ° C. in an inert atmosphere of 500 Torr or less using a vacuum induction melting furnace (VIM furnace). If it is less than 1240 ° C., VIM treatment cannot be performed because Mn does not melt.
When the temperature exceeds 1400 ° C., oxide and sulfide suspended in the molten Mn are remelted due to high temperature and taken into the molten Mn, and magnesium (Mg), calcium (Ca), oxygen (O ) And sulfur (S) concentrations are on the order of several hundred ppm to 1,000 ppm, and the final purity of the present invention cannot be achieved. The results are shown in Table 2.

Then, Ca was gradually added to the molten Mn in a range of 0.5 to 2.0% of the Mn weight to perform deoxidation and desulfurization. After completion of deoxidation and desulfurization, an ingot is produced by casting into an iron mold. After cooling the ingot, slag adhering to the ingot is removed.
Next, the Mn ingot was charged into a skull melting furnace, heated by reducing the pressure to 10 ⁻⁵ Torr or less with a vacuum pump, and after maintaining the molten state for 10 to 60 minutes, the melting reaction was terminated to obtain a high purity Obtain Mn.
Mn obtained by this production method has a total amount of impurity elements B, Mg, Al, Si, S, Ca, Cr, Fe, and Ni of 50 ppm or less, and 4N5 (99.995% excluding gas components) ) High purity Mn having the above purity.

Furthermore, the total amount of impurity elements B, Mg, Al, Si, S, Ca, Cr, Fe, and Ni is 50 ppm or less, and O and N that are gas components can each be less than 10 ppm.
In particular, the presence of O and N in electronic devices using Mn forms oxides or nitrides, which not only deteriorates the properties of Mn itself, but also oxidizes in composites or alloyed materials with Mn. In some cases, the influence of the formation of nitrides or nitrides (deterioration of characteristics) or the influence of diffusion of O or N (deterioration of characteristics) between adjacent materials may occur. The presence of Mn, which can be reduced, is extremely effective.
A summary of these steps is shown in FIG.

For skull dissolution, a normal skull dissolution apparatus can be used. In general, the skull furnace is cooled, and the raw material charged in the furnace is melted by induction heating, so that there is no contamination from the furnace.
In the purification of Mn, VIM dissolution removes S and O in advance with calcium (Ca), and then the skull furnace is used to remove the extremely increased Mg and Ca, and finally increase the purity of Mn. It can be said that the idea of aiming did not exist in the prior art.

Hereinafter, the present invention will be described with reference to examples, but these are for facilitating understanding of the invention, and the present invention is not limited to the examples or comparative examples.

Example 1
Commercially available flaky electrolytic Mn (purity 2N: 99%) was used as a starting material. The impurities of the raw material Mn are B: 15 ppm, Mg: 90 ppm, Al: 4.5 ppm, Si: 39 ppm, S: 280 ppm, Ca: 5.9 ppm, Cr: 2.9 ppm, Fe: 11 ppm, Ni: 10 ppm, O: 720-2500 ppm, N: 10-20 ppm.

(VIM dissolution process)
The Mn raw material was placed in a magnetic crucible and melted at a melting temperature of 1300 ° C. in an inert atmosphere of 200 Torr or less using a vacuum induction melting furnace (VIM furnace). And 1 weight% of calcium (Ca) of Mn weight was gradually added to this Mn molten metal, and deoxidation and desulfurization were performed. After completion of deoxidation and desulfurization, an ingot was manufactured by casting a molten Mn into an iron mold. After the ingot was cooled, the slag adhering to the ingot was removed.

Impurities in the ingot after dissolution were B: 14 ppm, Mg: 160 ppm, Al: 1.2 ppm, Si: 16 ppm, S: 16 ppm, Ca: 520 ppm, Cr: 2.5 ppm, Fe: 3.6 ppm, Ni: 1 .3 ppm, O: less than 10 ppm, and N: less than 10 ppm. The results are shown in Table 1.

As shown in Table 1, since it is a calcium reduction process, Ca is increased in the cast Mn, and Mg, which is a constituent element of the magnesia crucible, is easily reduced to Ca, part of which is Mn. It can be seen that Mg increases greatly when mixed in, but S, O and Ni are greatly reduced and other elements are also reduced.

(Skull dissolution process)
Next, the Mn ingot obtained by the above VIM melting is filled in a water-cooled crucible, the crucible is placed in a skull melting furnace, is made 10 ⁻⁵ Torr or less by a vacuum pump, heated by induction heating, After confirming the melting of a certain Mn ingot, the melting was terminated for 30 minutes, and solidified Mn was obtained.

Impurities of this Mn ingot were B: 8.1 ppm, Mg: 1.9 ppm, Al: 1.7 ppm, Si: 16 ppm, S: 2.7 ppm, Ca: 9.4 ppm, Cr: 1.1 ppm, Fe: 3 0.6 ppm, Ni: 1.1 ppm, O: less than 10 ppm, and N: less than 10 ppm.

The results are also shown in Table 1. As shown in Table 1, it can be seen that after skull dissolution, Ca and Mg increased by primary VIM dissolution are greatly reduced. Also, S is reduced. This is considered to be due to the removal of impurities that tend to volatilize by skull dissolution.

By performing VIM dissolution and skull dissolution treatment with the above-described deoxidation / desulfurization agent added, the electrolytic Mn raw material with a purity of 2N could be highly purified to 4N5 except for gas component elements.

According to the present invention, Mn with extremely high purity can be obtained, the manufacturing process is relatively simple, and the manufacturing cost can be reduced. Therefore, electronic component materials such as wiring materials and magnetic materials (magnetic heads), semiconductor components, etc. It is useful as a sputtering target material for producing a metal Mn used for the material, the same thin film, particularly a Mn-containing thin film. Since the present invention can be produced in a general-purpose furnace without requiring a special apparatus and can obtain high-purity Mn at a low cost and in a high yield as compared with the conventional distillation method, It can be said that the utility value of is high.

Claims

A method for producing high-purity Mn, in which a Mn raw material is put in a magnetic crucible and melted at a melting temperature of 1240 to 1400 ° C. in an inert atmosphere of 500 Torr or less using a vacuum induction melting furnace (VIM furnace), and calcium ( Ca) is added in the range of 0.5 to 2.0% of the Mn weight to perform deoxidation and desulfurization, and after completion of deoxidation and desulfurization, an ingot is produced by casting into an iron mold, and then this Mn ingot Is loaded into a skull melting furnace, heated by reducing the pressure to 10 −5 Torr or less with a vacuum pump, held in a molten state for 10 to 60 minutes, and then the melting reaction is terminated to obtain high purity Mn. A method for producing high-purity Mn.
High-purity Mn purified by vacuum induction melting (VIM) and skull melting, and the total amount of impurity elements B, Mg, Al, Si, S, Ca, Cr, Fe, Ni is 50 ppm or less, and gas components High-purity Mn having a purity of 4N5 (99.995%) or higher except for.
High-purity Mn purified by vacuum induction melting (VIM) and skull melting, and the total amount of impurity elements B, Mg, Al, Si, S, Ca, Cr, Fe, Ni is 50 ppm or less, and gas components High-purity Mn having a purity of 4N5 (99.995%) or more excluding elements and having oxygen (O) and nitrogen (N) as gas components of less than 10 ppm each.
The total amount of impurity elements B, Mg, Al, Si, S, Ca, Cr, Fe, and Ni is 50 ppm or less, and has a purity of 4N5 (99.995%) or more excluding gas component elements. High purity Mn.
The total amount of impurity elements B, Mg, Al, Si, S, Ca, Cr, Fe, and Ni is 50 ppm or less, and has a purity of 4N5 (99.995%) or more, excluding gas component elements, High purity Mn, characterized in that oxygen (O) and nitrogen (N) are less than 10 ppm each.