Preparation method of electronic-grade high-purity manganese metal

Abstract

The invention discloses a preparation method of electronic-grade high-purity manganese metal, which comprises the following steps: taking 99.8% manganese metal as an anode in an electrolytic bath, additionally arranging an ion diaphragm bag on the anode, taking a titanium plate as a cathode, and taking a manganese nitrate solution purified and adsorbed by alpha-manganese dioxide and chelating resin containing iminodiacetic acid group as an electrolyte. The method effectively avoids pollution of non-metal impurities and metal impurities, and has the technical advantage of high purity of the obtained manganese metal.

Description

Technical Field

[0001] The invention relates to a method for preparing electronic-grade high-purity metallic manganese, and belongs to the field of high-purity metal metallurgy. Background Art

[0002] With the continuous improvement of chip integration and the continuous reduction of chip size, the share of electronic grade high purity manganese in target material applications is increasing, and the market demand for high purity manganese as the main raw material is also gradually increasing, with broad profit margins. After the applicant's literature search and scientific and technological novelty search, there is no related industrial application of electronic grade high purity metal manganese. Therefore, electronic grade high purity metal manganese urgently needs a technological breakthrough.

[0003] In the prior art, the production of manganese metal is mostly carried out by electrolysis using manganese sulfate and ammonium sulfate as the medium, which has the following problems: ① The solid solubility of sulfur in manganese metal is relatively large, and the sulfate medium inevitably causes a high content of impurity sulfur; ② Addition of selenium dioxide as an additive to electrolytic manganese metal, selenium and sulfur are in the same main group and have similar physical and chemical properties, which also inevitably causes a high content of selenium in manganese metal.

[0004] Chinese patent CN115948769A discloses a method for electrolytic refining of high-purity metallic manganese, with metallic manganese as the anode, ruthenium-plated titanium plate as the cathode, and manganese sulfate aqueous solution as the starting electrolyte. The cathode and the anode are separated by a diaphragm cloth, and the power supply is turned on to electrolyze to obtain a manganese sulfate solution. The manganese sulfate solution is successively reduced by hydrogen peroxide under acidic conditions, ferric sulfate is precipitated to remove potassium and sodium ions, and manganese fluoride is precipitated and filtered to remove calcium and magnesium ions. The solution is introduced into the cathode area of ​​the electrolytic cell, and the manganese sulfate solution flows from the cathode area to the anode area. The liquid level in the cathode area is higher than that in the anode area. The temperature, cell voltage, and current density are set to electrolyze to obtain high-purity metallic manganese. This technology uses manganese sulfate electrolysis, which will produce impurity sulfur and affect the purity of the product. Summary of the invention

[0005] The object of the present invention is to provide a method for preparing electronic grade high-purity metallic manganese.

[0006] The technical solution of the present invention is a method for preparing electronic grade high-purity metallic manganese, comprising the following steps: 1. In the electrolytic cell, manganese metal is used as the anode, an ion diaphragm bag is installed on the anode, a titanium plate is used as the cathode, and manganese nitrate solution is used as the electrolyte for electrolysis; 2. Add manganese dioxide to the anode solution derived from the anode in step 1 for adsorption purification; 3. The solution in step 2 is purified by adsorption with chelating resin; 4. The solution in step 3 is introduced into the cathode area of ​​the electrolytic cell, and the temperature, current density and cell voltage of the electrolytic cell are adjusted to electrolyze to obtain electronic grade high-purity metallic manganese.

[0007] The purity of the metallic manganese used as the anode in step 1 is ≥99.8%.

[0008] In step 1, the center distance between the cathode and anode plates is 10-40 cm.

[0009] The manganese dioxide added for adsorption purification in step 2 is α-manganese dioxide, and the added amount is 0.01-0.04 mg / L.

[0010] The adsorption purification resin in step 3 is a chelating resin containing iminodiacetic acid groups, and the processing capacity is 0.01-0.04 mg / L.

[0011] In step 4, the manganese ion concentration in the solution in the electrolytic cell is 20-60 g / L, the pH value is between 7-8, the cathode current density is 100-200 A / m2, and the electrolysis temperature is 20-50°C.

[0012] In step 4, hydrogen peroxide is added to the electrolytic cell solution during the electrolysis process as an inhibitor of nitrous acid and high-valent manganese, and the added amount is 0.4-0.8 mL / L.

[0013] The metal impurity elements contained in the metal manganese are K, Na, Ca, Mg, Al, Cu, Zn, Fe, Co, Ni, and Pb elements, and the non-metallic impurity elements are S, Si, and Se. Compared with the prior art, the beneficial effects of the present invention are as follows: ① The electrolytic medium of the present invention is manganese nitrate, which does not contain sulfur, and the non-metallic element nitrogen is insoluble in metallic manganese, thus effectively avoiding the pollution of non-metallic impurity sulfur; ② The present invention does not use the additive selenium dioxide in the traditional electrolysis process, effectively avoiding the pollution of non-metallic impurity selenium; ③ The present invention uses α-manganese dioxide and a chelating resin containing iminodiacetic acid groups to purify and adsorb the electrolytic solution, effectively avoiding the pollution of non-metallic impurity silicon; ④ In the present invention, Au, Ag, Pt, Pd, Ru, Rh, Os, and Ir are inert metals and will not enter the solution during the electrolysis process. Instead, they will be deposited at the bottom of the electrolytic cell in the form of anode mud and will not contaminate the metallic manganese obtained by cathode electrolysis; ⑤ Elements such as K, Na, Ca, Mg, Al, Cu, Zn, Fe, Co, Ni, and Pb in the solution of the present invention will dissolve in the form of nitrates, be purified and adsorbed by α-manganese dioxide and chelating resin containing iminodiacetic acid groups, and will not accumulate at the cathode; ⑥ Hydrogen peroxide is added to the electrolytic cell solution as an inhibitor of nitrite and high-valent manganese. Hydrogen peroxide can react with nitrite to produce nitrate and water, and can also react with high-valent manganese compounds to produce divalent manganese ions, while inhibiting the discharge reaction of nitrate at the cathode to ensure the stability of the electrolytic reaction; ⑦ The purity of the electronic grade high-purity metallic manganese obtained by electrolysis in the present invention can reach 99.999%, which has the technical advantage of high purity. DETAILED DESCRIPTION

[0014] The present invention is further described below in conjunction with embodiments and comparative examples, but they are not intended to limit the present invention.

[0015] A method for preparing electronic grade high-purity metallic manganese comprises the following steps: 1. In the electrolytic cell, manganese metal is used as the anode, an ion diaphragm bag is installed on the anode, a titanium plate is used as the cathode, and manganese nitrate solution is used as the electrolyte for electrolysis; 2. Add manganese dioxide to the anode solution derived from the anode in step 1 for adsorption purification; 3. The solution in step 2 is purified by adsorption with chelating resin; 4. The solution in step 3 is introduced into the cathode area of ​​the electrolytic cell, and the temperature, current density and cell voltage of the electrolytic cell are adjusted to electrolyze to obtain electronic grade high-purity metallic manganese. Example

[0016] In the electrolytic cell, 99.8% metallic manganese is used as the anode, and an ion diaphragm bag is installed on the anode. The titanium plate is used as the cathode, and the electrolyte is the manganese nitrate solution purified and adsorbed by α-manganese dioxide and a chelating resin containing iminodiacetic acid. The treatment capacity of the chelating resin is 0.03 mg / L, which is the amount of chelating resin required to treat 1 liter of solution. The distance between the anode and cathode plates is set to 25 cm, the manganese ion concentration is 40 g / L, 0.4 mL / L of hydrogen peroxide is added as an inhibitor of nitrite and high-valent manganese, the pH value is 7, and the cathode current density is 120 A / m 2 The electrolysis temperature was 25℃ and the electrolysis was carried out for 48h. The purity of the electrolytic manganese metal was 99.9998%. The amount of α-manganese dioxide added was 0.02mg / L. Example

[0017] In the electrolytic cell, 99.8% metallic manganese is used as the anode, and an ion diaphragm bag is installed on the anode. The titanium plate is used as the cathode, and the manganese nitrate solution purified and adsorbed by α-manganese dioxide and a chelating resin containing iminodiacetic acid is used as the electrolyte. The processing capacity of the chelating resin is 0.02 mg / L. The distance between the anode and cathode plates is set to 30 cm, the manganese ion concentration is 50 g / L, 0.5 mL / L of hydrogen peroxide is added as an inhibitor of nitrite and high-valent manganese, the pH value is 7, and the cathode current density is 150 A / m 2 The electrolysis temperature was 30℃ and the electrolysis was carried out for 72h. The purity of the electrolytic manganese metal was 99.9995%. The amount of α-manganese dioxide added was 0.03mg / L. Example

[0018] In the electrolytic cell, 99.8% metallic manganese is used as the anode, and an ion diaphragm bag is installed on the anode. The titanium plate is used as the cathode, and the manganese nitrate solution purified and adsorbed by α-manganese dioxide and a chelating resin containing iminodiacetic acid is used as the electrolyte. The treatment capacity of the chelating resin is 0.04 mg / L, the distance between the anode and cathode plates is set to 40 cm, the manganese ion concentration is 60 g / L, 0.8 mL / L of hydrogen peroxide is added as an inhibitor of nitrite and high-valent manganese, the pH value is 7.5, and the cathode current density is 140 A / m 2 The electrolysis temperature was 40℃ and the electrolysis was carried out for 72h. The purity of the electrolytic manganese metal was 99.9993%. The amount of α-manganese dioxide added was 0.04mg / L. Example

[0019] In the electrolytic cell, 99.9% metallic manganese is used as the anode, and an ion diaphragm bag is installed on the anode. The titanium plate is used as the cathode, and the manganese nitrate solution purified and adsorbed by α-manganese dioxide and a chelating resin containing iminodiacetic acid is used as the electrolyte. The treatment capacity of the chelating resin is 0.01 mg / L, the distance between the anode and cathode plates is set to 15 cm, the manganese ion concentration is 40 g / L, 0.45 mL / L of hydrogen peroxide is added as an inhibitor of nitrite and high-valent manganese, the pH value is 7.5, and the cathode current density is 120 A / m 2 The electrolysis temperature was 25℃ and the electrolysis was carried out for 72h. The purity of the electrolytic manganese metal was 99.9996%. The amount of α-manganese dioxide added was 0.02mg / L.

Claims

1. A method for preparing electronic grade high-purity metallic manganese, characterized in that: The steps include:

1. In the electrolytic cell, manganese metal is used as the anode, an ion diaphragm bag is installed on the anode, a titanium plate is used as the cathode, and manganese nitrate solution is used as the electrolyte for electrolysis; 2. Add manganese dioxide to the anode solution derived from the anode in step 1 for adsorption purification; 3. The solution in step 2 is purified by adsorption with chelating resin; 4. The solution in step 3 is introduced into the cathode area of ​​the electrolytic cell, and the temperature, current density and cell voltage of the electrolytic cell are adjusted to electrolyze to obtain electronic grade high-purity metallic manganese.

2. The method for preparing electronic grade high-purity metallic manganese according to claim 1, characterized in that: The purity of the metallic manganese used as the anode in step 1 is ≥99.8%.

3. The method for preparing electronic grade high-purity metallic manganese according to claim 1, characterized in that: In step 1, the center distance between the cathode and anode plates is 10-40 cm.

4. The method for preparing electronic grade high-purity metallic manganese according to claim 1, characterized in that: The manganese dioxide added for adsorption purification in step 2 is α-manganese dioxide, and the added amount is 0.01-0.04 mg / L.

5. The method for preparing electronic grade high purity metallic manganese according to claim 1, characterized in that: The adsorption purification resin in step 3 is a chelating resin containing iminodiacetic acid groups, and the processing capacity is 0.01-0.04 mg / L.

6. The method for preparing electronic grade high purity metallic manganese according to claim 1, characterized in that: In step 4, the manganese ion concentration in the solution in the electrolytic cell is 20-60 g / L, the pH value is between 7-8, and the cathode current density is 100-200 A / m 2 , the electrolysis temperature is 20-50℃.

7. The method for preparing electronic grade high purity metallic manganese according to claim 1, characterized in that: In step 4, hydrogen peroxide is added to the electrolytic cell solution during the electrolysis process as an inhibitor of nitrous acid and high-valent manganese, and the added amount is 0.4-0.8 mL / L.