Adsorbent for impurity removal of manganese sulfate solution, preparation method and high-purity manganese electrolytic refining process

Abstract

The invention relates to the technical field of wet electrolytic manganese metal, and particularly discloses an adsorbent for removing impurities from a manganese sulfate solution, a preparation method of the adsorbent and a high-purity manganese electrolytic refining process. The specific surface area and the reaction activity of the material are further improved; grafting polyethyleneimine on the surface of the activated mixed material under the action of a cross-linking agent epoxy chloropropane, and further grafting tannic acid under the cross-linking action of amino and phenolic hydroxyl to obtain a composite modified mixed material; the composite modified mixed material provided by the invention contains a large number of hydroxyl groups, ester groups and amino groups which have strong adsorption effects on heavy metal ions, so that the adsorption performance of the mixed material on the heavy metal ions is further improved; by means of the process, the purity of the prepared product manganese reaches up to 99.99% or above, and expanded industrial production of high-purity manganese is facilitated.

Description

Technical Field

[0001] The invention relates to the technical field of wet electrolytic manganese metal, and in particular to an adsorbent for removing impurities from a manganese sulfate solution, a preparation method and a process for electrolytically refining high-purity manganese. Background Art

[0002] Manganese is mainly used in the steel industry in traditional fields, accounting for more than 90%, and there is a saying that "no manganese, no steel". At the same time, it also plays an irreplaceable and important role in strategic emerging industries involving manganese, such as semiconductor targets, lithium-ion batteries, high manganese-based damping alloys, and graphene. Especially in the semiconductor target industry, it is of great significance to break through the "stuck neck" technology, lead the development of high-end industries, and support advanced manufacturing.

[0003] Manganese has special physical and chemical properties, and it is difficult to effectively purify it to more than 99.999% by conventional physical or chemical methods. Only one or two countries in the world can produce high-purity manganese. Due to the expensive preparation method, the price of high-purity manganese is very high. The purity of electrolytic manganese in my country is generally around 99.7%, and manganese with a purity exceeding 99.99% has not yet been produced domestically.

[0004] At present, the traditional method for preparing high-purity manganese is too complicated, and the purity of metallic manganese is maintained at a range below 99.99%, which has the disadvantage of low grade. For example, Chinese patent document CN104040030A discloses a high-purity manganese and a method for manufacturing the same, wherein the method obtains a secondary raw material by pickling the manganese raw material, and electrolyzes the secondary raw material to obtain manganese with a purity of 3N or more. The product obtained by the method has low purity and contains more impurities, which is difficult to meet the use requirements of semiconductor metal interconnects.

[0005] Chinese patent document CN103937999A discloses a method for extracting metallic manganese by vacuum distillation of ferromanganese. The method adopts distillation of ferromanganese under vacuum conditions to separate manganese and iron to extract metallic manganese from ferromanganese. During the distillation process, raw materials are continuously added to the furnace through a feeding system to ensure the continuity and efficiency of the distillation process. The distilled manganese vapor is transported to a crystallization collection chamber through a pipeline to be cooled, crystallized and collected. However, the above process flow for preparing metallic manganese is complicated, has high requirements on production equipment, and is expensive in production cost.

[0006] Therefore, how to simplify the preparation process of high-purity manganese, improve product purity and reduce impurity content is the main problem that needs to be solved urgently. Summary of the invention

[0007] In view of the deficiencies in the prior art, the object of the present invention is to provide an adsorbent for removing impurities from a manganese sulfate solution, a preparation method and a process for electrolytically refining high-purity manganese.

[0008] In order to achieve the above object, the present invention adopts the following technical scheme:

[0009] In a first aspect, the present invention provides a method for preparing an adsorbent for removing impurities from a manganese sulfate solution, comprising the following steps:

[0010] S1. Prepare an activated mixed material

[0011] Add alkali lignin to deionized water, stir to dissolve, then add fly ash thereto, mix evenly, and then adjust the pH of the solution to 3-5. After dehydration, drying, grinding and sieving, and microwave activation treatment, an activated mixed material is obtained.

[0012] In this step, the mass ratio of the fly ash to the alkali lignin is 10-20:8-15. In some embodiments of the present invention, for example, 10:8, 10:10, 10:12, 10:15, 15:8, 15:10, 15:15, 20:8, 20:10, 20:12, 20:15 can be selected, but it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0013] In this step, the power of the microwave activation treatment is 600-1000W, for example, 600W, 650W, 700W, 750W, 800W, 850W, 900W, 950W, 1000W can be selected; the time of the microwave activation treatment is 5-15min, for example, 5min, 6min, 7min, 8min, 9min, 10min, 11min, 12min, 13min, 14min, 15min can be selected; but it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0014] The fly ash used in this step is a common industrial waste residue, and the alkali lignin is a high molecular organic matter mainly derived from paper-making black liquor. Both have the characteristics of wide sources and low prices, but the adsorption effect on heavy metal ions is relatively low. In the present invention, the fly ash is first added to the alkali lignin solution, and the structure on the surface of the fly ash is destroyed by the alkaline environment, thereby increasing the specific surface area of the fly ash. Then, the pH of the solution is adjusted to acidic, and the alkali lignin precipitates in the acidic solution and adheres to the surface of the fly ash. By mixing the fly ash and the alkali lignin, the obtained mixed material has both a high specific surface area and a three-dimensional space network structure, which is beneficial to adsorb heavy metal ions; subsequently, by performing microwave activation treatment on the mixed material, the non-thermal effect of the microwave helps to promote the breaking of macromolecular clusters and clusters in the material, further enhancing the specific surface area and reaction activity of the material itself.

[0015] S2. Prepare an amino-modified mixed material

[0016] Disperse the activated mixed material in deionized water, then add polyethyleneimine and epichlorohydrin thereto, heat and stir for reaction. After the reaction is completed, filter, wash and dry the reaction product to obtain the amino-modified mixed material.

[0017] In this step, the mass ratio of the activated mixed material, polyethyleneimine and epichlorohydrin is 10-15:6-8:5-10. In some embodiments of the present invention, for example, 10:6:5, 10:8:10, 12:6:5, 12:6:8, 12:8:10, 15:6:5, 15:6:8, 15:8:10 can be selected, but it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0018] In this step, the temperature of the heating and stirring reaction is 60-80 °C, for example, 60 °C, 65 °C, 70 °C, 75 °C, 80 °C can be selected; the time of the heating and stirring reaction is 3-5 h, for example, 3 h, 3.5 h, 4 h, 4.5 h, 5 h can be selected, but it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0019] In this step, through the action of the cross-linking agent epichlorohydrin, polyethyleneimine is grafted on the surface of the activated mixed material. Polyethyleneimine contains a large number of amino groups, which improves the adsorption performance of the mixed material for heavy metal ions. At the same time, polyethyleneimine can also act as a "bridge" for subsequent reactions.

[0020] S3. Prepare the composite-modified mixed material

[0021] Disperse the amino-modified mixed material in deionized water, adjust the pH of the solution to 3-5, then add tannic acid thereto, stir for reaction. After the reaction is completed, filter, wash and dry the reaction product to obtain the composite-modified mixed material.

[0022] In this step, the mass ratio of the amino-modified mixed material and tannic acid is 10-20:5-10. In some embodiments of the present invention, for example, 10:5, 10:8, 10:10, 12:5, 12:8, 12:10, 15:5, 15:8, 15:10, 20:5, 20:10 can be selected, but it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0023] In this step, the temperature of the stirring reaction is 70-85 °C. In some embodiments of the present invention, for example, 70 °C, 75 °C, 80 °C, 85 °C can be selected; the time of the stirring reaction is 2-4 h, for example, 2 h, 2.5 h, 3 h, 3.5 h, 4 h can be selected, but it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0024] In this step, the tannic acid molecule used contains a large number of phenolic hydroxyl groups. Through the cross-linking effect between amino groups and phenolic hydroxyl groups, a composite modified mixed material is obtained. The composite modified mixed material contains a large number of hydroxyl, ester, and amino groups that have a strong adsorption effect on heavy metal ions, further improving the adsorption performance of the mixed material for heavy metal ions.

[0025] S4. Prepare an adsorbent for removing impurities from manganese sulfate solution

[0026] Mix the composite modified mixed material, sodium carboxymethyl cellulose, and deionized water, extrude and form, then dry and crush to obtain particles with a particle size of 0.5 - 2.0 mm, that is, an adsorbent for removing impurities from manganese sulfate solution is obtained.

[0027] In this step, the mass ratio of the composite modified mixed material, sodium carboxymethyl cellulose, and deionized water is 100:3 - 6:20 - 30. In some embodiments of the present invention, for example, 100:3:20, 100:3:25, 100:3:30, 100:4:20, 100:5:20, 100:5:25, 100:5:30, 100:6:20, 100:6:25, 100:6:30 can be selected, but it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0028] In the second aspect, the present invention provides an adsorbent for removing impurities from manganese sulfate solution prepared by the above preparation method.

[0029] In the third aspect, the present invention further provides a process for electrolytic refining of high-purity manganese, including the following steps:

[0030] (1) After dissolving manganese sulfate, adjust the pH of the solution to 6 - 7, then add the above adsorbent, perform purification and impurity removal treatment, and then perform ion exchange through an ion exchange column to obtain a purified solution;

[0031] (2) Add a manganese salt and an ammonium salt to the purified solution obtained in step (1) for solution adjustment treatment to obtain an adjusted solution;

[0032] (3) Adjust the pH of the adjusted solution to 6 - 7 and perform electrolytic refining to obtain high-purity manganese.

[0033] Specifically, in step (1), the dosage of the adsorbent is 0.1 - 10 g / L. For example, 0.1 g / L, 0.5 g / L, 1 g / L, 2 g / L, 3 g / L, 5 g / L, 6 g / L, 8 g / L, 10 g / L can be selected, but it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0034] Specifically, in step (1), the resin selected in the ion exchange column is a resin commonly used in the art. For example, D851 chelating resin can be selected.

[0035] Specifically, in step (2), the manganese salt includes manganese chloride, and the ammonium salt includes ammonium chloride.

[0036] Specifically, in step (2), the concentration of Mn in the adjusting solution 2+ is 30 - 40 g / L. For example, 30 g / L, 32 g / L, 34 g / L, 35 g / L, 36 g / L, 38 g / L, 40 g / L can be selected; the concentration of NH4 + is 120 - 140 g / L. For example, 120 g / L, 122 g / L, 124 g / L, 125 g / L, 128 g / L, 130 g / L, 132 g / L, 135 g / L, 138 g / L, 140 g / L can be selected; however, it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0037] Specifically, in step (3), the electrolysis temperature is 35 - 40 °C. For example, 35 °C, 36 °C, 37 °C, 38 °C, 39 °C, 40 °C can be selected; the current density is 250 - 270 A / m 2 , for example, 250 A / m 2 , 252 A / m 2 , 254 A / m 2 , 255 A / m 2 , 258 A / m 2 , 260 A / m 2 , 265 A / m 2 , 268 A / m 2 , 270 A / m 2 , but it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] (1) The fly ash used in the present invention is a common industrial waste residue, and alkali lignin is a high - molecular organic substance mainly derived from paper - making black liquor. Both have the characteristics of wide sources and low prices, but their adsorption effects on heavy metal ions are relatively low. In the present invention, fly ash is first added to the alkali lignin solution. The alkaline environment is used to destroy the surface structure of fly ash, thereby increasing the specific surface area of fly ash. Then, the pH of the solution is adjusted to acidic, and alkali lignin precipitates in the acidic solution and adheres to the surface of fly ash. By mixing fly ash and alkali lignin, the obtained mixed material has both a high specific surface area and a three - dimensional spatial network structure, which is beneficial to the adsorption of heavy metal ions.

[0040] (2) By subjecting the mixed material to microwave activation treatment, the non-thermal effect of microwave helps to promote the rupture of large molecular clusters and aggregates within the material, further enhancing the specific surface area and reaction activity of the material itself.

[0041] (3) Through the action of the cross-linking agent epichlorohydrin, polyethyleneimine is grafted onto the surface of the activated mixed material. Polyethyleneimine contains a large number of amino groups, which improves the adsorption performance of the mixed material for heavy metal ions. At the same time, polyethyleneimine can also serve as a "bridge" for subsequent reactions. Subsequently, tannic acid is further grafted through the cross-linking of amino and phenolic hydroxyl groups to obtain a composite modified mixed material. The composite modified mixed material provided by the present invention contains a large number of hydroxyl, ester, and amino groups that have strong adsorption effects on heavy metal ions, further improving the adsorption performance of the mixed material for heavy metal ions.

[0042] (4) By using an adsorbent to purify and remove impurities from the manganese sulfate solution, the effect of deep impurity removal from the solution is obvious, the operability is strong, the purity of the manganese product is significantly improved, the process operation is simple, and the purity of the product manganese is as high as over 99.99%, which is conducive to the large-scale industrial production of high-purity manganese. Specific Embodiments

[0043] The present invention will be further described in detail below through specific preferred embodiments, but the present invention is not limited to the following embodiments.

[0044] It should be noted that unless otherwise specified, the chemical reagents involved in the present invention are purchased through commercial channels.

[0045] The fly ash used in the embodiments of the present invention is Class II fly ash; the manufacturer of alkali lignin is Rizhao Feiyang Biotechnology Co., Ltd.; the CAS number of polyethyleneimine is 9002-98-6, and the relative molecular mass is 6000.

[0046] Example 1

[0047] A preparation method of an adsorbent for removing impurities from manganese sulfate solution, comprising the following steps:

[0048] S1. Add 8 g of alkali lignin to 150 mL of deionized water, stir to dissolve, then add 10 g of fly ash thereto, mix evenly, then adjust the pH of the solution to 4, dehydrate, dry, grind through a 200-mesh sieve, and then perform microwave activation treatment. The power of the microwave activation treatment is 800 W and the time is 10 min to obtain an activated mixed material;

[0049] S2. Disperse 10 g of the activated mixed material in 150 mL of deionized water, then add 6 g of polyethyleneimine and 5 g of epichlorohydrin thereto, and heat and stir the reaction at 60 °C for 5 h. After the reaction is completed, filter, wash, and dry the reaction product to obtain the amino-modified mixed material;

[0050] S3. Disperse 10 g of the amino-modified mixed material in 150 mL of deionized water, adjust the pH of the solution to 4, then add 5 g of tannic acid thereto, and stir and reflux the reaction at 70 °C for 4 h. After the reaction is completed, filter, wash, and dry the reaction product to obtain the composite-modified mixed material;

[0051] S4. Mix 100 g of the composite-modified mixed material, 3 g of sodium carboxymethylcellulose, and 20 g of deionized water, extrude and form, dry and crush, and take particles with a particle size of 0.5 - 2.0 mm to obtain the adsorbent for removing impurities from the manganese sulfate solution.

[0052] Example 2

[0053] A preparation method of an adsorbent for removing impurities from a manganese sulfate solution, comprising the following steps:

[0054] S1. Add 10 g of alkali lignin to 150 mL of deionized water, stir to dissolve, then add 15 g of fly ash thereto, mix evenly, then adjust the pH of the solution to 3, dehydrate, dry, grind through a 200-mesh sieve, and then perform microwave activation treatment. The power of the microwave activation treatment is 1000 W and the time is 5 min to obtain the activated mixed material;

[0055] S2. Disperse 15 g of the activated mixed material in 150 mL of deionized water, then add 8 g of polyethyleneimine and 10 g of epichlorohydrin thereto, and heat and stir the reaction at 80 °C for 3 h. After the reaction is completed, filter, wash, and dry the reaction product to obtain the amino-modified mixed material;

[0056] S3. Disperse 10 g of the amino-modified mixed material in 150 mL of deionized water, adjust the pH of the solution to 4, then add 8 g of tannic acid thereto, and stir and reflux the reaction at 85 °C for 2 h. After the reaction is completed, filter, wash, and dry the reaction product to obtain the composite-modified mixed material;

[0057] S4. Mix 100 g of the composite-modified mixed material, 6 g of sodium carboxymethylcellulose, and 30 g of deionized water, extrude and form, dry and crush, and take particles with a particle size of 0.5 - 2.0 mm to obtain the adsorbent for removing impurities from the manganese sulfate solution.

[0058] Example 3

[0059] A preparation method of an adsorbent for removing impurities from a manganese sulfate solution, comprising the following steps:

[0060] S1. Add 15 g of alkali lignin to 150 mL of deionized water, stir to dissolve, then add 20 g of fly ash thereto, mix evenly, then adjust the pH of the solution to 3, dehydrate, dry, grind through a 200-mesh sieve, and then perform microwave activation treatment with a power of 1000 W for 5 min to obtain an activated mixed material;

[0061] S2. Disperse 12 g of the activated mixed material in 150 mL of deionized water, then add 6 g of polyethyleneimine and 8 g of epichlorohydrin thereto, heat and stir at 70 °C for 4 h. After the reaction is completed, filter, wash and dry the reaction product to obtain an amino-modified mixed material;

[0062] S3. Disperse 20 g of the amino-modified mixed material in 150 mL of deionized water, adjust the pH of the solution to 4, then add 10 g of tannic acid thereto, stir and reflux at 80 °C for 3 h. After the reaction is completed, filter, wash and dry the reaction product to obtain a composite-modified mixed material;

[0063] S4. Mix 100 g of the composite-modified mixed material, 5 g of sodium carboxymethylcellulose and 25 g of deionized water, extrude and form, then dry and crush to obtain particles with a particle size of 0.5 - 2.0 mm, namely, an adsorbent for removing impurities from manganese sulfate solution.

[0064] Comparative Example 1

[0065] A preparation method of an adsorbent for removing impurities from manganese sulfate solution includes the following steps:

[0066] S1. Disperse 10 g of fly ash in 150 mL of deionized water, then add 6 g of polyethyleneimine and 5 g of epichlorohydrin thereto, heat and stir at 60 °C for 5 h. After the reaction is completed, filter, wash and dry the reaction product to obtain amino-modified fly ash;

[0067] S2. Disperse 10 g of the amino-modified fly ash in 150 mL of deionized water, adjust the pH of the solution to 4, then add 5 g of tannic acid thereto, stir and reflux at 70 °C for 4 h. After the reaction is completed, filter, wash and dry the reaction product to obtain a composite-modified fly ash;

[0068] S3. Mix 100 g of the composite-modified fly ash, 3 g of sodium carboxymethylcellulose and 20 g of deionized water, extrude and form, then dry and crush to obtain particles with a particle size of 0.5 - 2.0 mm, namely, an adsorbent for removing impurities from manganese sulfate solution.

[0069] Compared with Example 1, Comparative Example 1 does not use alkali lignin to treat fly ash.

[0070] Comparative Example 2

[0071] A preparation method of an adsorbent for removing impurities from manganese sulfate solution, comprising the following steps:

[0072] S1. Add 8 g of alkali lignin to 150 mL of deionized water, stir to dissolve, then add 10 g of fly ash thereto, mix evenly, then adjust the pH of the solution to 4, dehydrate, dry, grind through a 200-mesh sieve, and then perform microwave activation treatment. The power of the microwave activation treatment is 800 W and the time is 10 min to obtain an activated mixed material;

[0073] S2. Disperse 10 g of the activated mixed material in 150 mL of deionized water, then add 6 g of polyethyleneimine and 5 g of epichlorohydrin thereto, heat and stir at 60 °C for 5 h. After the reaction is completed, filter, wash and dry the reaction product to obtain an amino-modified mixed material;

[0074] S3. Mix 100 g of the amino-modified mixed material, 3 g of sodium carboxymethylcellulose and 20 g of deionized water, extrude and form, then dry and crush to obtain particles with a particle size of 0.5 - 2.0 mm, that is, obtain the adsorbent for removing impurities from manganese sulfate solution.

[0075] Compared with Example 1, Comparative Example 2 did not perform the grafting of tannic acid treatment.

[0076] Comparative Example 3

[0077] A preparation method of an adsorbent for removing impurities from manganese sulfate solution, comprising the following steps:

[0078] S1. Add 8 g of alkali lignin to 150 mL of deionized water, stir to dissolve, then add 10 g of fly ash thereto, mix evenly, then adjust the pH of the solution to 4, dehydrate, dry, grind through a 200-mesh sieve, and then perform microwave activation treatment. The power of the microwave activation treatment is 800 W and the time is 10 min to obtain an activated mixed material;

[0079] S2. Disperse 10 g of the activated mixed material in 150 mL of deionized water, adjust the pH of the solution to 4, then add 5 g of tannic acid thereto, stir and reflux at 70 °C for 4 h. After the reaction is completed, filter, wash and dry the reaction product to obtain a modified mixed material;

[0080] S3. Mix 100 g of the modified mixed material, 3 g of sodium carboxymethylcellulose and 20 g of deionized water, extrude and form, then dry and crush to obtain particles with a particle size of 0.5 - 2.0 mm, that is, obtain the adsorbent for removing impurities from manganese sulfate solution.

[0081] Comparative Example 3 was not treated with grafted polyethyleneimine compared with Example 1, and tannic acid was mainly attached to the surface of the mixed material through hydrogen bonding.

[0082] The adsorbents prepared in Examples 1-3 and Comparative Examples 1-3 of the present invention were subjected to performance tests, and the specific steps were as follows:

[0083] A manganese sulfate solution was prepared in the laboratory, in which the concentration of Co 2+ was 39.68 mg / L, the concentration of Ni 2+ was 19.86 mg / L, and the concentration of Fe 3+ was 5.18 mg / L. 100 ml was taken and placed in a 250 ml three-necked flask respectively, 0.01 g of the adsorbents prepared in Examples 1-3 and Comparative Examples 1-3 was added, stirred at room temperature for 2 h, and the supernatant was taken for testing. The adsorption rate was calculated, and the results are shown in Table 1.

[0084] Table 1 Adsorption results of different groups on heavy metal ions

[0085] <![CDATA[Co 2+ Removal rate (%)]]> <![CDATA[Ni 2+ Removal rate (%)]]> <![CDATA[Fe 3+ Removal rate (%)]]> Example 1 99.2 98.7 96.3 Example 2 99.5 98.3 95.8 Example 3 98.6 98.1 96.0 Comparative Example 1 78.3 75.4 63.7 Comparative Example 2 91.8 90.2 82.4 Comparative Example 3 85.7 79.6 71.5

[0086] As can be seen from Table 1, the adsorbents prepared in the examples of the present invention have good adsorption properties for heavy metal ions, and the removal rates of Co 2+ , Ni 2+ and Fe 3+ can reach more than 95%.

[0087] The present invention also provides a process for electrolytic refining of high-purity manganese, comprising the following steps:

[0088] (1) After dissolving manganese sulfate, adjust the pH of the solution to 6, then add the adsorbent prepared in Example 1, the addition amount is 1 g / L, stir at room temperature for 2 h, carry out purification and impurity removal treatment, and then carry out ion exchange through an ion exchange column. The resin selected is D851 chelating resin, the effective filtration height is 700 mm, the diameter is 100 mm, and the flow rate is 1 L / min to obtain a purified solution. The solutions before and after treatment are analyzed by ICPMS, and the impurity contents are shown in Table 2;

[0089] Table 2 Impurity contents before and after purification

[0090] Co (mg / L) Ni (mg / L) Fe (mg / L) Pb (mg / L) Cu (mg / L) Before treatment 4.34 2.36 1.89 <1.0 <0.5 After treatment 0.012 0.009 0.023 <0.005 <0.005

[0091] (2) Add manganese chloride and ammonium chloride to the purified solution obtained in step (1) for solution adjustment treatment to obtain an adjusted solution, and the concentration of Mn 2+ in the adjusted solution is 40 g / L, and the concentration of NH4 + is 120 g / L.

[0092] (3) Adjust the pH of the adjustment solution to 6.8 and conduct electrolytic refining. The electrolysis temperature is 38 °C and the current density is 260 A / m 2 , where the anode is low-purity manganese, and manganese ions in the electrolyte are reduced and deposited on the cathode to form a high-purity deposit, that is, a high-purity manganese product is obtained. The product is analyzed by GDMS, and the total purity of manganese is 99.993%.

[0093] Finally, it should be noted that the above embodiments do not limit the present invention in any form. For those skilled in the art, based on the present invention, some modifications and improvements can be made. Therefore, any modification or improvement made without departing from the spirit of the present invention falls within the scope of protection required by the present invention.

Claims

1. A preparation method of an adsorbent for removing impurities from manganese sulfate solution, characterized in that, It includes the following steps: S1. Add alkali lignin into deionized water, stir to dissolve it, then add fly ash into it, mix evenly, and then adjust the pH of the solution to 3 - 5. After dehydration, drying, grinding, sieving, and microwave activation treatment, an activated mixed material is obtained; S2. Disperse the activated mixed material in deionized water, then add polyethyleneimine and epichlorohydrin into it, heat and stir for reaction. After the reaction is completed, filter, wash, and dry the reaction product to obtain an amino - modified mixed material; S3. Disperse the amino - modified mixed material in deionized water, adjust the pH of the solution to 3 - 5, then add tannic acid into it, stir for reaction. After the reaction is completed, filter, wash, and dry the reaction product to obtain a composite - modified mixed material; S4. Mix the composite - modified mixed material, sodium carboxymethylcellulose, and deionized water, extrude and form, then dry and crush to obtain particles with a particle size of 0.5 - 2.0 mm, that is, an adsorbent for removing impurities from manganese sulfate solution is obtained.

2. The preparation method according to claim 1, characterized in that, In step S1, the mass ratio of fly ash to alkali lignin is 10 - 20:8 - 15.

3. The preparation method according to claim 1, wherein In step S2, the mass ratio of the activated mixed material, polyethyleneimine, and epichlorohydrin is 10 - 15:6 - 8:5 - 10.

4. The preparation method according to claim 1, characterized in that, In step S2, the temperature of the heating and stirring reaction is 60 - 80 °C, and the time of the heating and stirring reaction is 3 - 5 h.

5. The preparation method according to claim 1, wherein In step S3, the mass ratio of the amino - modified mixed material to tannic acid is 10 - 20:5 - 10.

6. The preparation method according to claim 1, characterized in that, In step S3, the temperature of the stirring reaction is 70 - 85 °C, and the time of the stirring reaction is 2 - 4 h.

7. The preparation method according to claim 1, characterized in that, In step S4, the mass ratio of the composite - modified mixed material, sodium carboxymethylcellulose, and deionized water is 100:3 - 6:20 - 30.

8. An adsorbent for removing impurities from manganese sulfate solution prepared by the preparation method according to any one of claims 1 - 7.

9. A process for electrolytic refining of high-purity manganese, characterized in that, It includes the following steps: (1) After dissolving manganese sulfate, adjust the pH of the solution to 6 - 7, then add the adsorbent according to claim 8, carry out purification and impurity removal treatment, and then conduct ion exchange through an ion exchange column to obtain a purified solution; (2) Add manganese salt and ammonium salt into the purified solution obtained in step (1) for solution adjustment treatment to obtain an adjusted solution; (3) Adjust the pH of the adjusted solution to 6 - 7, and carry out electrolytic refining to obtain high - purity manganese.

10. The process according to claim 9, characterized in that, In step (2), the concentration of Mn in the adjustment liquid 2+ is 30 - 40 g / L, and the concentration of NH4 + is 120 - 140 g / L.