JPS6259530A - Production of high-purity manganese compound - Google Patents

Abstract

PURPOSE:To obtain a high-purity manganese compound easily at a low cost, by adding ferromanganese or metallic manganese and an acid to an aqueous solution containing electrolyte to dissolve Mn and Fe, removing the insoluble component and precipitating the dissolved Mn and Fe. CONSTITUTION:Ferromanganese and/or metallic manganese are added to an aqueous solution containing electrolyte and an acid is added to the solution under stirring to effect the dissolution of manganese and iron while keeping the pH at 2-9. The undissolved component is separated and removed from the solution. Thereafter, the manganese and iron in the solution is precipitated and recovered. The electrolyte used in the above process is e.g. ammonium chloride, ammonium nitrate, ammonium acetate or alkali metal salt, etc. The manganese compound is simple manganese compound or a mixture of a manganese compound and an iron compound. The ferromanganese or metallic manganese used as a raw material is crushed (preferably to >=60 mesh) and added to the electrolyte solution.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing a high-purity manganese compound, and particularly to a method for producing a manganese compound suitable as a raw material for manganese-based ferrite. .

[Conventional technology]

Conventionally, high-purity manganese compounds are produced by dissolving manganese ore in sulfuric acid, other heavy metals as impurities are removed by the sulfide method, solvent extraction method, alcoholate method, etc., and iron is oxidized and separated and removed as hydroxide. , methods are being used to recover manganese as various salts.

Recently, in order to produce manganese compounds of even higher purity, ferromanganese or metallic manganese, which has fewer impurity elements such as alkali metals than manganese ore, are used, and these are directly dissolved in acid to remove heavy metals and iron, as in the conventional method. There is a method of purifying high-purity manganese compounds by combining separation and removal and recrystallization.

[Problems to be solved by the present invention]

1- or I7, the above-mentioned conventional method uses a direct acid treatment of the raw material (7 is used with a substance that dissolves manganese, so almost all of the impurities in the raw material are dissolved at the same time as manganese)-1 In order to remove this, several E2 requires many steps and requires a purification step using a complicated recrystallization method, which has the disadvantage that not only is the processing efficiency low, but also that it is not always possible to obtain a product of high purity.

The present invention improves the above-mentioned conventional drawbacks and provides a method for producing high-purity manganese compounds simply and in a low cost manner.

[Failure to solve the problem]

The present invention involves adding 1 type or 1 to 12 types of ferromanganese and metal manganese to an aqueous solution containing an electrolyte, stirring, adding acid, maintaining the pH at 2 to 9, and dissolving manganese and iron. This is a method for producing a high-purity manganese compound, in which dissolved matter is separated and removed, and manganese and iron in the solution are precipitated and recovered.

[action, effect]

The present invention is constructed as described above, and the electrolyte used in the drum is one or more of ammonium chloride, ammonium nitrate, ammonium acetate, or an alkali metal salt.

Furthermore, the manganese compound referred to in the present invention includes not only a manganese compound alone but also a mixture of a manganese compound and an iron compound.

Ferromanganese and metallic manganese, which are the raw materials of the present invention, are pulverized (preferably 60 mesh or less) and added to the electrolyte solution.

When ferromanganese and metallic manganese as mentioned above are added to water, some of the manganese and iron react with the water to form hydroxides, and the -( of the liquid rises to around 9.7°).

On the other hand, when the ferromanganese and metal manganese are added to a solution containing an electrolyte such as ammonium chloride, manganese and iron similarly produce hydroxides, but the buffering action of the electrolyte causes a decrease in Pi() in the solution. The degree to which - decreases depends on the concentration of the electrolyte, but 2 For example, in the case of a 2% solution of ammonium chloride, the pH is -9, 0%, 20%
In a solution, it is about 7.8.

Manganese hydroxide (FF) or iron hydroxide (I) completely precipitates on the ship's side. Since the values are about 9 or above and 8 or above, respectively, some manganese hydroxide and iron hydroxide are dissolved and others are formed. The part is precipitate 1. On the other hand, noble elements that tend to be more ionized than manganese and iron, that is, heavy metal elements, remain unreacted.

Manganese hydroxide produced as described above.

When acid is added to iron hydroxide, manganese hydroxide and iron hydroxide become salts and dissolve, making it possible to completely separate heavy metal elements. The acid used here may be any of hydrochloric acid, sulfuric acid, acetic acid, or nitric acid.

Next, FIG. 1 will be explained as an example. Figure 1 shows the change in -(1~) when ferromanganese powder is added to an electrolyte solution and hydrochloric acid is added dropwise to it. - decreases rapidly and becomes similar to conventional acid dissolution.

Therefore, when the ferromanganese becomes hot, all of the impurities in the ferromanganese are dissolved, so conventional methods have to be used to separate the impurities.

On the other hand, in a solution containing an electrolyte, the change due to the addition of hydrochloric acid becomes small due to the buffering effect of the electrolyte. In such a region (at least -=2 or more), unreacted substances are not affected by the acid and therefore do not dissolve at all,
Impurities can be completely separated.

In addition, as is clear from Figure 1, the buffering effect that keeps Pl constant increases as the electrolyte concentration increases, and when the concentration is 5% or more, the buffering effect keeps the Pl constant. It will be done. Therefore, in the present invention, it is preferable that the electrolyte concentration is 5% or more.

FIGS. 2 and 3 show the extraction p! in the present invention. (The content of impurities is shown respectively.

In this case, manganese and iron in the solutions of various Pi1 were recovered as carbonates, and oxides obtained by firing at 800° C. were used as samples.

As is clear from Fig. 2, heavy metals such as Cr, V, and Ni are seen to decrease rapidly at concentrations of 2 or more.

Furthermore, what is noteworthy about the present invention is that elements whose ionization tendency is more base than manganese and iron and nonmetallic elements can be removed at the same time. That is, as is clear from FIGS. 2 and 3, not only Mg and Ca but also nonmetallic elements such as P and Si can be removed.

It is thought that such nonmetallic elements are probably adsorbed by unreacted substances. Regarding P, no relationship with extracted PI is observed, but P in the raw material ferromanganese is 1400
Considering the ppm level, P can be efficiently removed regardless of whether it is extracted or not.

In addition, although Co shows a higher value than Cr, V, Ni, etc., it can be removed in the same way as Cr, V, Ni, etc. It is thought that Co forms an ammine complex in the solution, and this is adsorbed by unreacted substances.

As shown in Figures 2 and 3 above, the present invention can remove and separate impurities other than manganese and iron, but if a nitric acid compound is used as the electrolyte or nitric acid is used as the acid, iron can also be separated. I can do it. That is, if an oxidizing acid such as nitric acid is used, iron hydroxide (n) is oxidized to form hydroxyl-
Since the iron(III) hydroxide completely precipitates at temperatures above -5, it can be easily separated by over-separation together with unreacted substances.

This phenomenon is similar even when other oxidizing agents such as hydrogen peroxide are added or air is blown.

Therefore, in the present invention, if an appropriate acid is selected and used in consideration of the intended use of the final product, a high purity manganese compound consisting of a mixture of manganese and iron or manganese alone can be obtained.

Manganese and iron dissolved and separated as described above can be precipitated and separated as carbonates, oxalates, or hydroxides by conventional methods, and if necessary, they can be recovered as oxides. The high purity manganese compound thus obtained can be used as a raw material for ferrite.

As described above, the present invention can efficiently remove not only heavy metal elements in ferromanganese metal manganese but also non-metal elements such as P and Si, and does not require expensive equipment. This has the effect of being able to provide a high purity manganese compound at a low price.

〔Example〕

The specific configuration of the present invention will be explained using examples.

Example 1 10% ammonium chloride solution 200 ml, Vc, 60
Add ferromanganese powder 207 crushed to a mesh size or less, and while stirring the solution and maintaining the pH of the solution at 5 or more, 6M hydrochloric acid is successively added to dissolve the manganese and iron in the ferromanganese powder. Extracted. When the solution could no longer maintain -2 or more, the addition of 6M hydrochloric acid was stopped and one reaction was completed. Reaction time is approximately 3 hours.
The consumption amount of 6M hydrochloric acid was 106 ml, and the reaction rate (dissolution rate) of manganese and iron in ferromanganese calculated from the consumption amount of hydrochloric acid was about 90%.

Next, the reaction-completed solution was filtered to separate and remove undissolved substances, and then 251 ammonium hydrogen carbonate and 43 mt3 of 7.5M aqueous ammonia were added to the solution to adjust the pH of the solution to 7.8. Manganese and iron were precipitated as carbonates. The precipitated carbonate was separated by filtration and recovered.

In order to confirm the purification effect of the carbonate, the recovered carbonate was dried at 110°C and then calcined at 800°C for 90 minutes to form manganese and iron oxides (mainly composed of Mn203.Fe2O3), and analyzed for trace impurities. I did it. The results are shown in Table 1 in comparison with the trace impurity content in the ferromanganese used as a raw material, and the trace impurities in the product are significantly reduced.

Table 1 Example 2 A 12% ammonium chloride aqueous solution (150.8 g) was placed in a reaction container, and a powder of 2:1 mixture of ferromanganese and metallic manganese crushed to 60 mesh or less was added to the reaction container while stirring the solution. Gradually add 6M to the solution.
Hydrochloric acid was gradually injected to dissolve and extract manganese and iron in the powder. During the dissolution and extraction, the addition amount of the powder and the injection amount of 6M hydrochloric acid were adjusted so that the - of the solution was maintained at 5 or more, and the powder mixture was 15Ky (ferromanganese 10K9. gold ff manganese 5 to 2). was dissolved.

The time required for this dissolution treatment was approximately 10 hours, and the amount of 6M hydrochloric acid used was 78 p.

After the dissolution treatment was completed, the solution was allowed to stand for 12 hours, and then filtered to separate and remove undissolved substances. Next, add 17 to 9 of ammonium hydrogen carbonate and 26 to 7.5M aqueous ammonia to the solution.
After adding A and leaving the mixture for about 1 hour, manganese carbonate and iron carbonate, which had formed a precipitate, were separated by filtration and recovered. The yield was 23.7 to 5+ on a dry weight basis.

A part of the generated carbonate was calcined in the same manner as in Example 1 and analyzed as an oxide. The results are shown in Table 2.

Table 2 Example 3 Ferromanganese powder 20! i' (60 mesh or less) was added to 200 ml of 15% ammonium nitrate solution, and while stirring and keeping the ... of the solution above 5.
Manganese and iron were dissolved and extracted by sequentially adding MHNO:1. The end point of the reaction was when the - of the solution was 5 or more and 7 M HNO3 could no longer be added. At this time 7
The amount of M HNO3 consumed was 84 ml, and it took about 2 hours to complete the reaction.

Next, undissolved substances in the solution were separated by filtration, and the filtrate was mixed with 221 ammonium hydrogen carbonate and 38 mol of 7.5 M ammonium water.
ml was added to adjust the pH of the solution to 7.6, and the manganese in the solution was precipitated as a carbonate, separated by filtration, and recovered. This removed iron is oxidized by nitrate and nitric acid, and is filtered and separated as the undissolved material.

In order to confirm the purification effect of the carbonate, the recovered carbonate was dried at 110'C and then calcined at 800C for 90 minutes.

The composition of the obtained manganese oxide is shown in Table 3 in comparison with the composition of ferromanganese used as a raw material.

When nitric acid is used as the acid as shown in Table 3, not only trace impurities but also iron can be separated and removed at a high rate.

Table 3 Example 4 Metallic manganese 209 pH pulverized to 60 mesh or less was added to a 15% ammonium acetate solution, and 7.5 M acetic acid was added with stirring to dissolve and extract the manganese at 15° or higher. The amount of 7.5M acetic acid consumed at this time was 95ml,
During the time required for extraction, 281 ammonium hydrogen carbonate and 48 ml of 7.5M ammonium water were added while stirring to adjust the pH of the solution to 7.2, and manganese was converted into carbonate and precipitated.

It was collected by filtration.

The purity of said carbonate? To confirm this, it was dried at 110°C and then fired at 800°C for 90 minutes. Table 4 shows the impurity content and Mn content of the raw material manganese metal and the product.

[Brief explanation of the drawing]

FIG. 1 is a titration curve of an electrolytic solution, and FIGS. 2 and 3 are graphs showing the relationship between impurity content and -, respectively.

Claims (2)

[Claims] (1) Add one or both of ferromanganese and metal manganese to an aqueous solution containing an electrolyte, stir, add acid, and adjust the pH.
1. A method for producing a high-purity manganese compound, which comprises dissolving manganese and iron and separating and removing undissolved substances by maintaining the pH value between 2 and 9, and then precipitating and recovering the manganese and iron in the solution. (2) A method for producing a high-purity manganese compound according to claim 1, characterized in that iron is precipitated and separated using a nitric acid compound as an electrolyte and/or nitric acid as an acid.