KR101274365B1 - Method for manufacturing manganese carbonate - Google Patents

Abstract

An object of the present invention is to easily obtain high-purity manganese carbonate with little impurities such as sodium, using an aqueous solution of manganese having a strong acidity, such as an extract aftertaste.
It is a manufacturing method of manganese carbonate in which the acidic manganese solution is adjusted to pH 7-8 with ammonia water, and a carbon dioxide gas is blown into the liquid to obtain manganese carbonate with less impurities.

Description

Method of producing manganese carbonate {METHOD FOR MANUFACTURING MANGANESE CARBONATE}

The present invention aims to recover high purity manganese carbonate at high recovery rate, particularly with respect to sodium, in recovering manganese as acidic manganese from an acidic manganese solution.

In recent years, the amount of use of manganese is increasing in not only battery materials such as electronic devices and lithium ion secondary batteries but also alloys and various other materials. In these devices, batteries, materials and the like, manganese is used in combination with not only manganese but also other metal components. For this reason, when recycling manganese used for an apparatus, a battery, etc., it is necessary to isolate only manganese from these metal components. As one of the methods for this separation, there is a method using an acidic extractant, and is generally used as disclosed in Japanese Patent Application Laid-Open No. 2008-231522 (Patent Document 1). However, if an acidic extractant is used, it is necessary to contact with an acid in order to extract the metal component from the extractant into the water phase. In order to transfer most of the manganese contained in the extractant to the water phase, the water phase in contact with the extractant must be changed to a strong acidity. The aqueous solution of manganese obtained through such extraction process is strongly acidic.

When pH adjustment is carried out to obtain manganese oxide or manganese carbonate from the acidic manganese solution obtained in this way, for example, using a hydroxide such as caustic soda or caustic caliber increases the concentration of sodium and potassium ions in the aqueous phase, It was difficult to recover manganese which is a target object in the state which prevented mixing, ie, to obtain a high purity manganese compound.

Japanese Patent Application Publication No. 2008-231522

In addition, when separating manganese as a carbonate from a manganese solution, it is also considered to produce a precipitate of manganese carbonate by using carbonates, such as sodium carbonate, directly as a pH adjuster and a carbonate feed agent, or using an aqueous solution, and to isolate | separate by filtration. However, in this method, the sodium component in the liquid is mixed in the filtrate, and there is a fear that the sodium component is mixed after filtration and drying. In addition, as described above, when sodium is already increased in the solution by adjusting the pH, it becomes a condition in which sodium is more likely to precipitate, and there is a high possibility that sodium is mixed in manganese carbonate. If a large amount of washing water is used to avoid the incorporation of sodium, manganese carbonate will spill into the filtrate. Thus, in the process of recycling a valuable metal, the method of extracting only manganese by the extraction process using an acidic extractant, and obtaining a high purity manganese carbonate was calculated | required. An object of the present invention is to obtain a high-purity manganese carbonate by a simple method.

Thus, the above problems have been solved, and the following inventions have been achieved. (1) A method for producing manganese carbonate in which the acidic manganese solution is adjusted to pH 7-8 with ammonia water, and a carbon dioxide gas is blown into the liquid to obtain manganese carbonate with less impurities. (2) The manufacturing method of manganese carbonate whose Na in manganese carbonate as described in said (1) is 100 mass ppm or less. (3) The manganese carbonate according to any one of the above (1) or (2), wherein during the carbon dioxide gas blowing, ammonia water is continuously added, the pH is continuously maintained at 7-8 to obtain manganese carbonate with less impurities. Manufacturing method. (4) The manufacturing method of manganese carbonate whose Na in manganese carbonate as described in said (3) is 100 mass ppm or less.

By the present invention, the following effects are obtained. (1) Manganese carbonate with little sodium is easily obtained. (2) In recovering manganese from the extraction liquid, manganese carbonate with less impurities such as sodium is easily obtained from the acidic liquid.

1 is a diagram illustrating a processing flow of one embodiment of the present invention.
FIG. 2 is a diagram showing an XRD pattern of precipitation of manganese carbonate of one embodiment of the present invention. FIG.

In this invention, the manganese concentration of the acidic manganese liquid used as a raw material can use arbitrary things. Since manganese carbonate can be recovered until the manganese concentration after carbonation is reduced to about 5 ppm, it is also possible to recover manganese carbonate from the lean solution if the cost is suitable. On the contrary, even if it is a high concentration aqueous solution, if it does not appear to precipitate more than solubility, it can be used as a raw material.

The pH is adjusted before carbonizing the acidic manganese solution. In the present invention, ammonia water is used. With ammonia water, contamination of metal components other than manganese can be avoided. The pH may be a pH at which carbon dioxide is dissolved. Ammonia water is preferably adjusted to, for example, about 20 to 40 mass%.

Carbonation is also performed at pH 5, but pH 7 to pH 8 are preferred in view of the reaction rate and yield. The manganese solution after pH adjustment is carbonated using carbon dioxide. The blowing speed may be adjusted according to the scale of manufacture.

For example, at the beaker level, about 100 ml / min is appropriate, and when it scales up, it can blow in large quantities. Blowing inlets are more finely divided so that the blown carbon dioxide is dissolved in the liquid. In addition, while blowing carbonic acid gas, although pH falls, it is preferable to perform the adjustment also with ammonia water. Also in this case, it is preferable to maintain pH at 7-8. This is because it is suitable for obtaining manganese carbonate. After sufficiently reacting, high purity manganese carbonate can be obtained by filtration, washing and drying.

(First embodiment)

According to the processing flow shown in FIG. 1, one embodiment of the present invention will be described below. 250 ml of aqueous manganese solution (pH 0, manganese concentration 75 g / L) was prepared, and 50 ml of 28 mass% ammonia water was added. The pH after addition is 7.1. Carbon dioxide was blown into this manganese liquid at a flow rate of 100 ml / min. If you continue to blow carbon dioxide, the reaction starts to lower the pH. Therefore, ammonia water was added slowly to maintain pH at 7-8. Blowing of carbon dioxide was performed for 3hr so that manganese in liquid might fully react. The amount of ammonia water added in the carbon dioxide blowing amounted to 50 ml.

The precipitate formed after the carbon dioxide blowing was filtered off from the liquid phase. The precipitate was dried and then subjected to X-ray diffraction (hereinafter referred to as XRD). The XRD pattern of the precipitate obtained by the Example is shown in FIG. When XRD was performed, it matched with the peak of manganese carbonate like the arrow shown in FIG. The concentration of the filtrate was measured by ICP emission, and the manganese concentration was 6 ppm. From this result, it turned out that almost 100% of the manganese contained in original manganese aqueous solution was recoverable as manganese carbonate. The sodium impurity concentration in the manganese carbonate was measured and found to be 98 mass ppm.

(Comparative Example 1)

250 ml of aqueous manganese solution (pH 0, manganese concentration 75 g / L) was prepared, and 50 ml of 28 mass% ammonia water was added. PH after addition is 7.1. Carbon dioxide was blown into this manganese liquid at a flow rate of 100 ml / min. As the carbon dioxide continued to blow, the pH began to drop by the reaction. Blowing of carbon dioxide was performed for 3hr so that manganese in liquid might fully react. pH dropped to 6. The precipitate formed after the carbon dioxide blowing was filtered off from the liquid phase. XRD was carried out after drying the precipitate, which coincided with the peak of manganese carbonate. The concentration of the filtrate was measured by ICP emission, and the manganese concentration was 50 g / L. From these results, it turned out that about 33% of manganese contained in the original aqueous solution of manganese was recoverable as manganese carbonate.

(Comparative Example 2)

250 ml of aqueous manganese solution (pH 0, manganese concentration 75 g / L) was prepared, and 50 ml of 28 mass% ammonia water was added. PH after addition is 7.1. 50 g of sodium carbonate was added to this manganese solution to generate a precipitate. The resulting precipitate was separated from the liquid phase by filtration. XRD was carried out after drying the precipitate, which coincided with the peak of manganese carbonate. The concentration of the filtrate was measured by ICP emission, and the manganese concentration was 5 ppm or less. From these results, it turned out that almost 100% of the manganese contained in the original aqueous solution of manganese was recoverable as manganese carbonate. It was 5000 ppm when the sodium impurity concentration in manganese carbonate was measured.

(Third comparative example)

250 ml of an aqueous solution of manganese (pH 0, manganese concentration 75 g / L) was prepared. Carbon dioxide was blown into this manganese liquid at a flow rate of 100 ml / min. The pH did not change. The formation of precipitates could not be observed. The concentration of the filtrate was measured by ICP emission, and the concentration of manganese was 75 g / L.

Claims (4)

A method of producing manganese carbonate, wherein the acidic manganese solution is adjusted to pH 7 to 8 with ammonia water, and carbon dioxide is blown into the liquid to obtain manganese carbonate having Na of 100 mass ppm or less in manganese carbonate. delete The method for producing manganese carbonate according to claim 1, wherein ammonia water is continuously added during carbonic acid gas blowing to maintain the pH at 7 to 8 to obtain manganese carbonate having Na of 100 mass ppm or less. delete

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