Method for recycling manganese metal through electrolytic manganese waste residues

Abstract

The invention provides a method for recycling manganese metal through electrolytic manganese waste residues, and relates to the technical field of resource utilization of the electrolytic manganese residues. The method for recycling the metal manganese through the electrolytic manganese waste residues comprises the following steps that the electrolytic manganese waste residues are washed with water, and washing liquid is collected; mixing the washing liquid with ammonium sulfate and selenium dioxide to obtain a low-concentration manganese electrolyte; and the low-concentration manganese electrolyte is electrolyzed, metal manganese is obtained, and recovery of the metal manganese is completed. The concentration of manganese ions in the electrolyte is 12-15 g / L, the concentration of ammonium sulfate is 80-100 g / L, and the concentration of selenium dioxide is 0.025-0.035 g / L. The manganese ions in the electrolytic manganese waste residue washing liquid are successfully recovered by adding ammonium sulfate and selenium dioxide with a certain concentration. The problems that manganese is difficult to separate out on a negative plate, manganese feeding is abnormal, flaking, alkali emission, blackening of a polar plate, turbid electrolyte, unstable cell voltage and the like due to the fact that the concentration of manganese ions in the washing liquid is low are solved.

Description

Technical Field

[0001] The invention relates to the technical field of resource utilization of electrolytic manganese slag, and in particular to a method for recovering metallic manganese through electrolytic manganese waste slag. Background Art

[0002] Manganese is an important strategic resource and basic material, widely used in various fields. The electrolytic manganese industry belongs to the traditional high-energy consumption, high-pollution and resource-based industry. The amount of electrolytic manganese waste slag is large and the utilization rate is low. Not only will a large amount of electrolytic manganese waste slag be added every year, but there are also a large number of historical manganese waste slag. In order to promote the high-quality development of the electrolytic manganese industry, the technology for recycling manganese elements in electrolytic manganese waste slag needs to be studied in depth. In the electrolytic manganese industry, the slurry of manganese ore powder after acid leaching, chemical combination and impurity removal is sent to the filter press workshop for filtration, and the filtrate is a qualified electrolyte and is sent to the electrolysis workshop. The filter cake produced in the filtration process is the electrolytic manganese waste slag, which is generally transported directly to the tailings pond for stacking and treatment. Due to the high water content of manganese waste slag in the filtration process (25% to 30%), some useful substances such as soluble manganese and ammonium sulfate and most of the impurity metals (iron, copper, cobalt, nickel, lead, zinc, etc.) are taken away, which will cause certain pollution to the surrounding environment. How to further process manganese waste slag, recover useful materials from it, increase corporate benefits, protect the environment, and achieve efficient utilization of manganese resources has become an important issue that manganese electrolysis companies must face. It is also an important direction for scientific research teams to tackle technical problems. However, the manganese concentration in the washing liquid after washing the electrolytic manganese waste slag is low, which makes electrolytic recovery more difficult.

[0003] In the traditional direct current electrolysis to prepare manganese metal, Mn 2+ In alkaline conditions, it is not only easy to hydrolyze, but also easy to be oxidized into high-valent manganese compounds MnOOH (Mn2O3·3H2O) and MnO2. In addition, the electrolysis equipment will also have a certain impact on the electrolysis. The potential distribution of the anode electrode of traditional electrolysis equipment is uneven, and the power loss is large; a serious hydrogen evolution reaction will occur on the cathode, which reduces the current efficiency of electrolytic manganese and directly affects the output and economic benefits of metallic manganese; some "protruding growth" dendrites will form on the cathode surface during the electrodeposition process, which will also cause a decrease in current efficiency and a decrease in output, and is one of the main factors causing short circuits between electrodes and unstable production; at the same time, dendritic metallic manganese is easy to fall off and enter the flushing wastewater during the plate flushing process, resulting in manganese loss. Therefore, traditional electrolysis equipment is not suitable for electrolyzing electrolytes with low manganese ion content.

[0004] In summary, in order to solve the problems of resource waste and environmental pollution caused by the difficulty in resource utilization of electrolytic manganese waste slag, technical personnel in this field urgently need to develop a technical solution that can efficiently and energy-savingly electrolytically recover manganese elements in manganese waste slag washing liquid. Summary of the invention

[0005] The object of the present invention is to provide a method for recovering metallic manganese through electrolytic manganese waste slag, so as to solve the problems of waste of manganese resources and ammonium sulfate and environmental pollution caused by the difficulty in resource utilization of electrolytic manganese waste slag.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] The present invention provides a method for recovering metallic manganese through electrolytic manganese waste residue, comprising the following steps:

[0008] The electrolytic manganese waste residue is washed with water and the washing liquid is collected; the washing liquid is mixed with ammonium sulfate and selenium dioxide to obtain a low-concentration manganese electrolyte; the low-concentration manganese electrolyte is electrolyzed to obtain metallic manganese, thereby completing the recovery of metallic manganese;

[0009] The low concentration manganese electrolyte contains Mn 2+ The concentration of is 12-15 g / L, the concentration of ammonium sulfate is 80-100 g / L, and the concentration of SeO2 is 0.025-0.035 g / L.

[0010] Preferably, the flow rate of the low-concentration manganese electrolyte during the electrolysis process is 2.5 to 5 L / min;

[0011] The electrolysis temperature is 25-45°C.

[0012] Preferably, the cathode current density of the electrolysis is 300-400 A / m 2 .

[0013] Preferably, the electrolysis is carried out in a diaphragm electrolyzer;

[0014] The diaphragm electrolyzer comprises a cell body, a false bottom, a diaphragm mold frame, a diaphragm bag, a serpentine tube, a cathode plate and an anode plate.

[0015] Preferably, the diaphragm frame is made of fir wood, and a diaphragm bag is placed outside the diaphragm frame. The lower part of the diaphragm bag is hollow and divides the tank body into three parts which are connected at the lower part.

[0016] Preferably, the serpentine tube is placed on the outer wall of the electrolytic cell, and a coolant flows through the serpentine tube.

[0017] Preferably, the cathode plate is a 1Cr18Ni9Ti stainless steel plate with a thickness of 1 to 2 mm;

[0018] The anode plate is a lead-antimony-tin-silver quaternary alloy plate with a thickness of 8 to 15 mm.

[0019] Preferably, the percentage of each element in the lead-antimony-tin-silver quaternary alloy plate is: 98.15-98.45wt% lead, 0.2wt% antimony, 1.2-1.5wt% tin, and 0.15wt% silver.

[0020] Preferably, the effective area of ​​the anode plate is 55% to 60% of the effective area of ​​the cathode plate;

[0021] The anode plate is provided with grid holes.

[0022] The present invention has at least the following beneficial effects:

[0023] The invention successfully recovers manganese ions in the washing liquid of electrolytic manganese waste residue by adding a certain concentration of ammonium sulfate and selenium dioxide, thereby solving the problems of difficulty in precipitating manganese on the cathode plate, abnormal manganese addition, shelling, alkali generation, blackening of the plate, turbid electrolyte, unstable cell voltage, etc. caused by low manganese ion concentration in the washing liquid. DETAILED DESCRIPTION

[0024] The present invention provides a method for recovering metallic manganese through electrolytic manganese waste residue, comprising the following steps:

[0025] The electrolytic manganese waste residue is washed with water and the washing liquid is collected; the washing liquid is mixed with ammonium sulfate and selenium dioxide to obtain a low-concentration manganese electrolyte; the low-concentration manganese electrolyte is electrolyzed to obtain metallic manganese, thereby completing the recovery of metallic manganese;

[0026] The low concentration manganese electrolyte contains Mn 2+ The concentration of is 12-15 g / L, preferably 12.5-14.5 g / L, further preferably 13-14 g / L, more preferably 13.5 g / L; the concentration of ammonium sulfate is 80-100 g / L, preferably 85-95 g / L, further preferably 87-92 g / L, more preferably 90 g / L; the concentration of SeO2 is 0.025-0.035 g / L, preferably 0.027-0.032 g / L, further preferably 0.029-0.031 g / L, more preferably 0.030 g / L.

[0027] In the present invention, if the manganese ion concentration in the solution of electrolytic manganese waste slag after washing and filter pressing does not reach 12-15 g / L, electrolytic wastewater generated in the electrolytic manganese industry can be added to adjust the manganese ion concentration; the content of heavy metals such as iron, copper, cobalt, nickel, lead, zinc, etc. in the washing liquid of electrolytic manganese waste slag is too large and cannot meet the parameter requirements of qualified electrolyte for manganese electrolysis. Before or after adding ammonium sulfate or selenium dioxide, it is necessary to perform a de-weighting treatment to remove the influence of heavy metal ions on electrolysis.

[0028] In the present invention, the pH value of the low-concentration manganese electrolyte needs to be adjusted to 6-6.8 before electrolysis.

[0029] In the present invention, the flow rate of the low-concentration manganese electrolyte during the electrolysis process is 2.5 to 5 L / min, preferably 3 to 4.5 L / min, and further preferably 3.5 to 4 L / min. As the flow rate increases, the current efficiency gradually increases. When the flow rate reaches about 4 L / min, the current efficiency reaches a peak value. If the flow rate is too large, the recovery rate is significantly reduced.

[0030] In the present invention, the electrolysis temperature is 25-45°C, preferably 35-43°C, and more preferably 41.07°C. If the temperature is too low, the current efficiency is low and the energy consumption is high. If the temperature is too high, the electrolysis device cannot work normally.

[0031] In the present invention, the cathode current density of the electrolysis is 300-400A / m 2 , preferably 320~380A / m 2 , more preferably 340 to 360 A / m 2 , more preferably 350A / m 2 .

[0032] In the present invention, the electrolysis is carried out in a diaphragm electrolyzer;

[0033] The diaphragm electrolyzer comprises a cell body, a false bottom, a diaphragm mold frame, a diaphragm bag, a serpentine tube, a cathode plate and an anode plate.

[0034] In the present invention, the diaphragm frame is made of fir wood, and a diaphragm bag is placed on the diaphragm frame. The lower part of the diaphragm bag is hollow and divides the tank body into three parts which are connected at the lower part.

[0035] In the present invention, the cathode plate and the anode plate are placed crosswise in a positive-covering-negative manner and there is no direct contact between the anode plate and the cathode plate.

[0036] In the present invention, the serpentine tube is placed on the outer wall of the electrolytic cell, a coolant flows through the serpentine tube, the coolant may be water or oil, and the serpentine tube is made of metal.

[0037] During the electrolysis process, coolant is required to cool the electrolytic cell to ensure the normal electrolysis.

[0038] In the present invention, the cathode plate is a 1Cr18Ni9Ti stainless steel plate with a thickness of 1 to 2 mm, preferably 1.2 to 1.8 mm, and more preferably 1.5 mm.

[0039] In the present invention, the anode plate is a lead-antimony-tin-silver quaternary alloy plate with a thickness of 8 to 15 mm, preferably 9 to 14 mm, more preferably 10 to 13 mm, and more preferably 11 to 12 mm.

[0040] In the present invention, the percentage of each element in the lead-antimony-tin-silver quaternary alloy plate is: 98.15-98.45wt% lead, 0.2wt% antimony, 1.2-1.5wt% tin, 0.15wt% silver, preferably 98.2-98.4wt% lead, 0.2wt% antimony, 1.3-1.4wt% tin, 0.15wt% silver, and further preferably 98.25-98.35wt% lead, 0.2wt% antimony, 1.35wt% tin, and 0.15wt% silver.

[0041] In the present invention, the effective area of ​​the anode plate is 55% to 60% of the effective area of ​​the cathode plate, preferably 56 to 59%, and more preferably 57 to 58%.

[0042] In the present invention, the anode plate is provided with grid holes.

[0043] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0044] Example 1

[0045] Wash the electrolytic manganese waste residue with water, filter and obtain the washing liquid, adjust the Mn content of the washing liquid 2+ The concentration is 13.7g / L, the concentration of ammonium sulfate is 84.88g / L, and hydrogen peroxide is added (the volume concentration of hydrogen peroxide is 5%, and the volume ratio of hydrogen peroxide added to the washing liquid is 100mL:1000L) to make the Fe in the solution 2+ Oxidized to Fe 3+ , add ammonium sulfide solution (the concentration of ammonium sulfide solution is 8 g / L, and the volume ratio of the added amount of ammonium sulfide solution to the washing liquid is 25 mL: 1000 L) for preliminary weight removal, filter press to remove precipitate, add ammonia water to the filtrate to adjust the pH value of the system to 6.43, add sodium fume (the ratio of the added amount of sodium fume to the filtrate is 50 g: 1000 L) for further weight removal, filter press again, add selenium dioxide to the filtrate (control the concentration of selenium dioxide to 0.031 g / L) to obtain a low-concentration manganese electrolyte.

[0046] The above-mentioned low-concentration manganese electrolyte is electrolyzed by a diaphragm electrolytic cell, which comprises a cell body, a false bottom, a diaphragm frame, a diaphragm bag, a serpentine lead pipe, a cathode plate and an anode plate. The diaphragm frame is made of fir wood, and the diaphragm bag is covered on the diaphragm frame. The lower part of the diaphragm bag is hollow and the cell body is divided into three parts connected at the lower part. The left and right sides are anode parts, which are provided with 11 lead-antimony-tin-silver quaternary alloy anode plates with a thickness of 15mm (the size is 570mm×470mm, and the percentage of each element is respectively: lead 98.15wt%, antimony 0.2wt%, tin 1.5wt%, silver 0.15wt%), and the cathode part is inside the diaphragm bag, which is provided with 10 1Cr18Ni9Ti stainless steel plate cathode plates with a thickness of 1.5mm (the size is 600mm×500mm). The outer wall of the electrolytic cell is provided with a stainless steel serpentine pipe for cooling, and tap water is passed through the pipe. The temperature of the electrolyte during the electrolysis process was 41.07°C and the current density during the electrolysis was 327A / m 2 The flow rate of low-concentration manganese electrolyte was 3.98L / min. After 24 hours of electrolysis, the average weight increase of the cathode plate was 3.648kg / piece, the current efficiency was 80.36%, and the recovery rate was 45.33%.

[0047] Example 2

[0048] Wash the electrolytic manganese waste residue with water, filter and obtain the washing liquid, adjust the Mn content of the washing liquid 2+ The concentration is 13.02g / L, the concentration of ammonium sulfate is 81.1g / L, and hydrogen peroxide is added (the volume concentration of hydrogen peroxide is 5%, and the volume ratio of hydrogen peroxide added to the washing liquid is 100mL:1000L) to make the Fe in the solution 2+ Oxidized to Fe 3+ , add ammonium sulfide solution (the concentration of ammonium sulfide solution is 8 g / L, and the volume ratio of the added amount of ammonium sulfide solution to the washing liquid is 25 mL: 1000 L) for preliminary weight removal, filter press to remove precipitate, add ammonia water to the filtrate to adjust the pH value of the system to 6.51, add sodium fume (the ratio of the added amount of sodium fume to the filtrate is 50 g: 1000 L) for further weight removal, filter press again, add selenium dioxide to the filtrate (control the concentration of selenium dioxide to 0.031 g / L) to obtain a low-concentration manganese electrolyte.

[0049] The above-mentioned low-concentration manganese electrolyte is electrolyzed by a diaphragm electrolytic cell, which comprises a cell body, a false bottom, a diaphragm frame, a diaphragm bag, a serpentine lead pipe, a cathode plate and an anode plate. The diaphragm frame is made of fir wood, and the diaphragm bag is covered on the diaphragm frame. The lower part of the diaphragm bag is hollow and the cell body is divided into three parts connected at the lower part. The left and right sides are anode parts, which are provided with 11 lead-antimony-tin-silver quaternary alloy anode plates with a thickness of 15mm (the size is 570mm×470mm, and the percentage of each element is respectively: lead 98.15wt%, antimony 0.2wt%, tin 1.5wt%, silver 0.15wt%), and the cathode part is inside the diaphragm bag, which is provided with 10 1Cr18Ni9Ti stainless steel plate cathode plates with a thickness of 1.5mm (the size is 600mm×500mm). The outer wall of the electrolytic cell is provided with a stainless steel serpentine pipe for cooling, and tap water is passed through the pipe. The temperature of the electrolyte in the electrolytic cell during the electrolysis process is 40.6°C, and the current density during electrolysis is 327A / m 2 The flow rate of low-concentration manganese electrolyte was 3.0L / min. After 24 hours of electrolysis, the average weight increase of the cathode plate was 3.264kg / piece, the current efficiency was 71.81%, and the recovery rate was 54.45%.

[0050] Example 3

[0051] Wash the electrolytic manganese waste residue with water, filter and obtain the washing liquid, adjust the Mn content of the washing liquid 2+ The concentration is 14.1g / L, the concentration of ammonium sulfate is 87.53g / L, and hydrogen peroxide is added (the volume concentration of hydrogen peroxide is 5%, and the volume ratio of hydrogen peroxide added to the washing liquid is 100mL:1000L) to make the Fe in the solution 2+ Oxidized to Fe 3+ , add ammonium sulfide solution (the concentration of ammonium sulfide solution is 8 g / L, and the volume ratio of the added amount of ammonium sulfide solution to the washing liquid is 25 mL: 1000 L) for preliminary weight removal, filter press to remove precipitate, add ammonia water to the filtrate to adjust the pH value of the system to 6.51, add sodium fume (the ratio of the added amount of sodium fume to the filtrate is 50 g: 1000 L) for further weight removal, filter press again, add selenium dioxide to the filtrate (control the concentration of selenium dioxide to 0.035 g / L) to obtain a low-concentration manganese electrolyte.

[0052] The above-mentioned low-concentration manganese electrolyte is electrolyzed by a diaphragm electrolytic cell, which comprises a cell body, a false bottom, a diaphragm frame, a diaphragm bag, a serpentine lead pipe, a cathode plate and an anode plate. The diaphragm frame is made of fir wood, and the diaphragm bag is covered on the diaphragm frame. The lower part of the diaphragm bag is hollow and the cell body is divided into three parts connected at the lower part. The left and right sides are anode parts, which are provided with 11 lead-antimony-tin-silver quaternary alloy anode plates with a thickness of 15mm (the size is 570mm×470mm, and the percentage of each element is respectively: lead 98.15wt%, antimony 0.2wt%, tin 1.5wt%, silver 0.15wt%), and the cathode part is inside the diaphragm bag, which is provided with 10 1Cr18Ni9Ti stainless steel plate cathode plates with a thickness of 1.5mm (the size is 600mm×500mm). The outer wall of the electrolytic cell is provided with a stainless steel serpentine pipe for cooling, and tap water is passed through the pipe. The temperature of the electrolyte in the electrolytic cell during the electrolysis process is 40.8°C, and the current density during electrolysis is 366A / m 2 The flow rate of low-concentration manganese electrolyte was 3.0L / min. After 24 hours of electrolysis, the average weight gain of the cathode plate was 3.312kg / piece, the current efficiency was 65.2%, and the recovery rate was 51.99%.

[0053] Example 4

[0054] Wash the electrolytic manganese waste residue with water, filter and obtain the washing liquid, adjust the Mn content of the washing liquid 2+ The concentration is 13.87g / L, the concentration of ammonium sulfate is 84.95g / L, and hydrogen peroxide is added (the volume concentration of hydrogen peroxide is 5%, and the volume ratio of hydrogen peroxide added to the washing liquid is 100mL:1000L) to make the Fe in the solution 2+ Oxidized to Fe 3+ , add ammonium sulfide solution (the concentration of ammonium sulfide solution is 8 g / L, and the volume ratio of the added amount of ammonium sulfide solution to the washing liquid is 25 mL: 1000 L) for preliminary weight removal, filter press to remove precipitate, add ammonia water to the filtrate to adjust the pH value of the system to 6.41, add sodium fume (the ratio of the added amount of sodium fume to the filtrate is 50 g: 1000 L) for further weight removal, filter press again, add selenium dioxide to the filtrate (control the concentration of selenium dioxide to 0.031 g / L) to obtain a low-concentration manganese electrolyte.

[0055] The above-mentioned low-concentration manganese electrolyte is electrolyzed by a diaphragm electrolytic cell, which comprises a cell body, a false bottom, a diaphragm frame, a diaphragm bag, a serpentine lead pipe, a cathode plate and an anode plate. The diaphragm frame is made of fir wood, and the diaphragm bag is covered on the diaphragm frame. The lower part of the diaphragm bag is hollow and the cell body is divided into three parts connected at the lower part. The left and right sides are anode parts, which are provided with 11 lead-antimony-tin-silver quaternary alloy anode plates with a thickness of 15mm (the size is 570mm×470mm, and the percentage of each element is respectively: lead 98.15wt%, antimony 0.2wt%, tin 1.5wt%, silver 0.15wt%), and the cathode part is inside the diaphragm bag, which is provided with 10 1Cr18Ni9Ti stainless steel plate cathode plates with a thickness of 1.5mm (the size is 600mm×500mm). The outer wall of the electrolytic cell is provided with a stainless steel serpentine pipe for cooling, and tap water is passed through the pipe. The temperature of the electrolyte in the electrolytic cell during the electrolysis process was 41.1°C, and the current density during electrolysis was 328A / m 2 The flow rate of low-concentration manganese electrolyte was 3.49 L / min. After 24 hours of electrolysis, the average weight gain of the cathode plate was 3.408 kg / piece, the current efficiency was 74.7%, and the recovery rate was 47.73%.

[0056] Example 5

[0057] Wash the electrolytic manganese waste residue with water, filter and obtain the washing liquid, adjust the Mn content of the washing liquid 2+ The concentration is 13.16 g / L, the concentration of ammonium sulfate is 85.74 g / L, and hydrogen peroxide is added (the volume concentration of hydrogen peroxide is 5%, and the volume ratio of hydrogen peroxide added to the washing liquid is 100 mL: 1000 L) to make the Fe in the solution 2+ Oxidized to Fe 3+ , add ammonium sulfide solution (the concentration of ammonium sulfide solution is 8 g / L, and the volume ratio of the added amount of ammonium sulfide solution to the washing liquid is 25 mL: 1000 L) for preliminary weight removal, filter press to remove precipitate, add ammonia water to the filtrate to adjust the pH value of the system to 8.32, add sodium fume (the ratio of the added amount of sodium fume to the filtrate is 50 g: 1000 L) for further weight removal, filter press again, add selenium dioxide to the filtrate (control the concentration of selenium dioxide to 0.027 g / L) to obtain a low-concentration manganese electrolyte.

[0058] The above-mentioned low-concentration manganese electrolyte is electrolyzed by a diaphragm electrolytic cell, which comprises a cell body, a false bottom, a diaphragm frame, a diaphragm bag, a serpentine lead pipe, a cathode plate and an anode plate. The diaphragm frame is made of fir wood, and the diaphragm bag is covered on the diaphragm frame. The lower part of the diaphragm bag is hollow and the cell body is divided into three parts connected at the lower part. The left and right sides are anode parts, which are provided with 11 lead-antimony-tin-silver quaternary alloy anode plates with a thickness of 15mm (the size is 570mm×470mm, and the percentage of each element is respectively: lead 98.15wt%, antimony 0.2wt%, tin 1.5wt%, silver 0.15wt%), and the cathode part is inside the diaphragm bag, which is provided with 10 1Cr18Ni9Ti stainless steel plate cathode plates with a thickness of 1.5mm (the size is 600mm×500mm). The outer wall of the electrolytic cell is provided with a stainless steel serpentine pipe for cooling, and tap water is passed through the pipe. The temperature of the electrolyte in the electrolytic cell during the electrolysis process is 40°C, and the current density during electrolysis is 354A / m 2 The flow rate of low-concentration manganese electrolyte was 3.23 L / min. After 24 hours of electrolysis, the average weight increase of the cathode plate was 2.904 kg / piece, the current efficiency was 58.94%, and the recovery rate was 45.59%.

[0059] Example 6

[0060] Wash the electrolytic manganese waste residue with water, filter and obtain the washing liquid, adjust the Mn content of the washing liquid 2+ The concentration is 13.26g / L, the concentration of ammonium sulfate is 93.34g / L, and hydrogen peroxide is added (the volume concentration of hydrogen peroxide is 5%, and the volume ratio of hydrogen peroxide added to the washing liquid is 100mL:1000L) to make the Fe in the solution 2+ Oxidized to Fe 3+ , add ammonium sulfide solution (the concentration of ammonium sulfide solution is 8 g / L, and the volume ratio of the added amount of ammonium sulfide solution to the washing liquid is 25 mL: 1000 L) for preliminary weight removal, filter press to remove precipitate, add ammonia water to the filtrate to adjust the pH value of the system to 6.24, add sodium fume (the ratio of the added amount of sodium fume to the filtrate is 50 g: 1000 L) for further weight removal, filter press again, add selenium dioxide to the filtrate (control the concentration of selenium dioxide to 0.026 g / L) to obtain a low-concentration manganese electrolyte.

[0061] The above-mentioned low-concentration manganese electrolyte is electrolyzed by a diaphragm electrolytic cell, which comprises a cell body, a false bottom, a diaphragm frame, a diaphragm bag, a serpentine lead pipe, a cathode plate and an anode plate. The diaphragm frame is made of fir wood, and the diaphragm bag is covered on the diaphragm frame. The lower part of the diaphragm bag is hollow and the cell body is divided into three parts connected at the lower part. The left and right sides are anode parts, which are provided with 11 lead-antimony-tin-silver quaternary alloy anode plates with a thickness of 15mm (the size is 570mm×470mm, and the percentage of each element is respectively: lead 98.15wt%, antimony 0.2wt%, tin 1.5wt%, silver 0.15wt%), and the cathode part is inside the diaphragm bag, which is provided with 10 1Cr18Ni9Ti stainless steel plate cathode plates with a thickness of 1.5mm (the size is 600mm×500mm). The outer wall of the electrolytic cell is provided with a stainless steel serpentine pipe for cooling, and tap water is passed through the pipe. The temperature of the electrolyte in the electrolytic cell during the electrolysis process is 40°C, and the current density during electrolysis is 377A / m 2 The flow rate of low-concentration manganese electrolyte was 4.39 L / min. After 24 hours of electrolysis, the average weight gain of the cathode plate was 3.024 kg / piece, the current efficiency was 57.69%, and the recovery rate was 37.84%.

[0062] Example 7

[0063] Wash the electrolytic manganese waste residue with water, filter and obtain the washing liquid, adjust the Mn content of the washing liquid 2+ The concentration is 14.89 g / L, the concentration of ammonium sulfate is 75.19 g / L, and hydrogen peroxide is added (the volume concentration of hydrogen peroxide is 5%, and the volume ratio of hydrogen peroxide added to the washing liquid is 100 mL: 1000 L) to make the Fe in the solution 2+ Oxidized to Fe 3+ , add ammonium sulfide solution (the concentration of ammonium sulfide solution is 8 g / L, and the volume ratio of the added amount of ammonium sulfide solution to the washing liquid is 25 mL: 1000 L) for preliminary weight removal, filter press to remove precipitate, add ammonia water to the filtrate to adjust the pH value of the system to 6.84, add sodium fume (the ratio of the added amount of sodium fume to the filtrate is 50 g: 1000 L) for further weight removal, filter press again, add selenium dioxide to the filtrate (control the concentration of selenium dioxide to 0.028 g / L) to obtain a low-concentration manganese electrolyte.

[0064] The above-mentioned low-concentration manganese electrolyte is electrolyzed by a diaphragm electrolytic cell, which comprises a cell body, a false bottom, a diaphragm frame, a diaphragm bag, a serpentine lead pipe, a cathode plate and an anode plate. The diaphragm frame is made of fir wood, and the diaphragm bag is covered on the diaphragm frame. The lower part of the diaphragm bag is hollow and the cell body is divided into three parts connected at the lower part. The left and right sides are anode parts, which are provided with 11 lead-antimony-tin-silver quaternary alloy anode plates with a thickness of 15mm (the size is 570mm×470mm, and the percentage of each element is respectively: lead 98.15wt%, antimony 0.2wt%, tin 1.5wt%, silver 0.15wt%), and the cathode part is inside the diaphragm bag, which is provided with 10 1Cr18Ni9Ti stainless steel plate cathode plates with a thickness of 1.5mm (the size is 600mm×500mm). The outer wall of the electrolytic cell is provided with a stainless steel serpentine pipe for cooling, and tap water is passed through the pipe. The temperature of the electrolyte in the electrolytic cell during the electrolysis process is 39.41°C, and the current density during electrolysis is 299A / m 2 The flow rate of low-concentration manganese electrolyte was 2.77 L / min. After 24 hours of electrolysis, the average weight gain of the cathode plate was 2.856 kg / piece, the current efficiency was 68.55%, and the recovery rate was 45.67%.

[0065] Example 8

[0066] Wash the electrolytic manganese waste residue with water, filter and obtain the washing liquid, adjust the Mn content of the washing liquid 2+ The concentration is 13g / L, the concentration of ammonium sulfate is 80.11g / L, and hydrogen peroxide is added (the volume concentration of hydrogen peroxide is 5%, and the volume ratio of hydrogen peroxide added to the washing liquid is 100mL:1000L) to make the Fe in the solution 2+ Oxidized to Fe 3+ , add ammonium sulfide solution (the concentration of ammonium sulfide solution is 8 g / L, and the volume ratio of the added amount of ammonium sulfide solution to the washing liquid is 25 mL: 1000 L) for preliminary weight removal, filter press to remove precipitate, add ammonia water to the filtrate to adjust the pH value of the system to 6.76, add sodium fume (the ratio of the added amount of sodium fume to the filtrate is 50 g: 1000 L) for further weight removal, filter press again, add selenium dioxide to the filtrate (control the concentration of selenium dioxide to 0.023 g / L) to obtain a low-concentration manganese electrolyte.

[0067] The above-mentioned low-concentration manganese electrolyte is electrolyzed by a diaphragm electrolytic cell, which comprises a cell body, a false bottom, a diaphragm frame, a diaphragm bag, a serpentine lead pipe, a cathode plate and an anode plate. The diaphragm frame is made of fir wood, and the diaphragm bag is covered on the diaphragm frame. The lower part of the diaphragm bag is hollow and the cell body is divided into three parts connected at the lower part. The left and right sides are anode parts, which are provided with 11 lead-antimony-tin-silver quaternary alloy anode plates with a thickness of 15mm (the size is 570mm×470mm, and the percentage of each element is respectively: lead 98.15wt%, antimony 0.2wt%, tin 1.5wt%, silver 0.15wt%), and the cathode part is inside the diaphragm bag, which is provided with 10 1Cr18Ni9Ti stainless steel plate cathode plates with a thickness of 1.5mm (the size is 600mm×500mm). The outer wall of the electrolytic cell is provided with a stainless steel serpentine pipe for cooling, and tap water is passed through the pipe. The temperature of the electrolyte in the electrolytic cell during the electrolysis process is 39.23°C, and the current density is 328A / m 2 The flow rate of low-concentration manganese electrolyte was 2.52L / min. After 24 hours of electrolysis, the average weight increase of the cathode plate was 2.664kg / piece, the current efficiency was 58.36%, and the recovery rate was 53.23%.

[0068] Example 9

[0069] Wash the electrolytic manganese waste residue with water, filter and obtain the washing liquid, adjust the Mn content of the washing liquid 2+ The concentration is 14.31g / L, the concentration of ammonium sulfate is 79.53g / L, and hydrogen peroxide is added (the volume concentration of hydrogen peroxide is 5%, and the volume ratio of hydrogen peroxide added to the washing liquid is 100mL:1000L) to make the Fe in the solution 2+ Oxidized to Fe 3+ , add ammonium sulfide solution (the concentration of ammonium sulfide solution is 8 g / L, and the volume ratio of the added amount of ammonium sulfide solution to the washing liquid is 25 mL: 1000 L) for preliminary weight removal, filter press to remove precipitate, add ammonia water to the filtrate to adjust the pH value of the system to 6.24, add sodium fume (the ratio of the added amount of sodium fume to the filtrate is 50 g: 1000 L) for further weight removal, filter press again, add selenium dioxide to the filtrate (control the concentration of selenium dioxide to 0.034 g / L) to obtain a low-concentration manganese electrolyte.

[0070] The above-mentioned low-concentration manganese electrolyte is electrolyzed by a diaphragm electrolytic cell, which comprises a cell body, a false bottom, a diaphragm frame, a diaphragm bag, a serpentine lead pipe, a cathode plate and an anode plate. The diaphragm frame is made of fir wood, and the diaphragm bag is covered on the diaphragm frame. The lower part of the diaphragm bag is hollow and the cell body is divided into three parts connected at the lower part. The left and right sides are anode parts, which are provided with 11 lead-antimony-tin-silver quaternary alloy anode plates with a thickness of 15mm (the size is 570mm×470mm, and the percentage of each element is respectively: lead 98.15wt%, antimony 0.2wt%, tin 1.5wt%, silver 0.15wt%), and the cathode part is inside the diaphragm bag, which is provided with 10 1Cr18Ni9Ti stainless steel plate cathode plates with a thickness of 1.5mm (the size is 600mm×500mm). The outer wall of the electrolytic cell is provided with a stainless steel serpentine pipe for cooling, and tap water is passed through the pipe. The temperature of the electrolyte in the electrolytic cell during the electrolysis process is 39.34°C, and the current density during electrolysis is 327A / m 2 The flow rate of low-concentration manganese electrolyte was 2.58 L / min. After 24 hours of electrolysis, the average weight gain of the cathode plate was 0.904 kg / piece, the current efficiency was 63.78%, and the recovery rate was 53.11%.

[0071] Comparative Example 1

[0072] The only difference between this comparative example and Example 1 is that the concentration of selenium dioxide in the configured low-concentration manganese electrolyte is only 0.01 g / L.

[0073] The above-mentioned low-concentration manganese electrolyte without adding selenium dioxide is electrolyzed by using a diaphragm electrolytic cell, which comprises a cell body, a false bottom, a diaphragm frame, a diaphragm bag, a serpentine lead pipe, a cathode plate and an anode plate. The diaphragm frame is made of fir wood, and the diaphragm bag is covered on the diaphragm frame. The lower part of the diaphragm bag is hollow and the cell body is divided into three parts connected at the lower part. The left and right sides are anode parts, which are provided with 11 lead-antimony-tin-silver quaternary alloy anode plates with a thickness of 15mm (the size is 570mm×470mm, and the percentage content of each element is respectively: lead 98.15wt%, antimony 0.2wt%, tin 1.5wt%, silver 0.15wt%), and the inside of the diaphragm bag is a cathode part, which is provided with 10 1Cr18Ni9Ti stainless steel plate cathode plates with a thickness of 1.5mm (the size is 600mm×500mm). The outer wall of the electrolytic cell is provided with a stainless steel serpentine pipe for cooling, and tap water is passed through the pipe. The temperature of the electrolyte during the electrolysis process was 41.1°C and the current density during the electrolysis was 327A / m 2 The flow rate of low-concentration manganese electrolyte was 3.98L / min. After 24 hours of electrolysis, the average weight gain of the cathode plate was 1.628kg / piece, the current efficiency was 37.05%, and the recovery rate was 20.16%.

[0074] Comparative Example 2

[0075] The only difference between this comparative example and Example 1 is that the concentration of ammonium sulfate in the configured low-concentration manganese electrolyte is 50 g / L.

[0076] The above-mentioned low-concentration manganese electrolyte without ammonium sulfate is electrolyzed by a diaphragm electrolytic cell, which comprises a cell body, a false bottom, a diaphragm frame, a diaphragm bag, a serpentine lead pipe, a cathode plate and an anode plate. The diaphragm frame is made of fir wood, and the diaphragm bag is covered on the diaphragm frame. The lower part of the diaphragm bag is hollow and the cell body is divided into three parts connected at the lower part. The left and right sides are anode parts, which are provided with 11 lead-antimony-tin-silver quaternary alloy anode plates with a thickness of 15mm (the size is 570mm×470mm, and the percentage of each element is respectively: lead 98.15wt%, antimony 0.2wt%, tin 1.5wt%, silver 0.15wt%), and the inside of the diaphragm bag is a cathode part, which is provided with 10 1Cr18Ni9Ti stainless steel plate cathode plates with a thickness of 1.5mm (the size is 600mm×500mm). The outer wall of the electrolytic cell is provided with a stainless steel serpentine pipe for cooling, and tap water is passed through the pipe. The temperature of the electrolyte during the electrolysis process was 41.1°C and the current density during the electrolysis was 327A / m 2 The flow rate of low-concentration manganese electrolyte was 3.98 L / min. After 24 hours of electrolysis, the cathode plate weight increased by 1.865 kg, the current efficiency was 41.11%, and the recovery rate was 23.17%.

[0077] Comparative Example 3

[0078] The difference between this comparative example and Example 1 is that the concentration of ammonium sulfate in the prepared low-concentration manganese electrolyte is 50 g / L, and the concentration of selenium dioxide is 0.01 g / L.

[0079] The above-mentioned low-concentration manganese electrolyte without ammonium sulfate and selenium dioxide is electrolyzed by a diaphragm electrolytic cell, which comprises a cell body, a false bottom, a diaphragm frame, a diaphragm bag, a serpentine lead pipe, a cathode plate and an anode plate. The diaphragm frame is made of fir wood, and the diaphragm bag is covered on the diaphragm frame. The lower part of the diaphragm bag is hollow and the cell body is divided into three parts connected at the lower part. The left and right sides are anode parts, which are provided with 11 lead-antimony-tin-silver quaternary alloy anode plates with a thickness of 15mm (the size is 570mm×470mm, and the percentage of each element is respectively: lead 98.15wt%, antimony 0.2wt%, tin 1.5wt%, silver 0.15wt%), and the inside of the diaphragm bag is a cathode part, which is provided with 10 1Cr18Ni9Ti stainless steel plate cathode plates with a thickness of 1.5mm (the size is 600mm×500mm). The outer wall of the electrolytic cell is provided with a stainless steel serpentine pipe for cooling, and tap water is passed through the pipe. The temperature of the electrolyte during the electrolysis process was 41.1°C and the current density during the electrolysis was 327A / m 2The flow rate of low-concentration manganese electrolyte was 3.98 L / min. After 24 hours of electrolysis, the average weight gain of the cathode plate was 0.894 kg / piece, the current efficiency was 19.69%, and the recovery rate was 11.11%.

[0080] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for recovering metallic manganese from electrolytic manganese waste residue, characterized in that: The following steps are involved: The electrolytic manganese waste residue is washed with water and the washing liquid is collected; the washing liquid is mixed with ammonium sulfate and selenium dioxide to obtain a low-concentration manganese electrolyte; the low-concentration manganese electrolyte is electrolyzed to obtain metallic manganese, thereby completing the recovery of metallic manganese; The low concentration manganese electrolyte contains Mn 2+ The concentration of is 12-15 g / L, the concentration of ammonium sulfate is 80-100 g / L, and the concentration of SeO2 is 0.025-0.035 g / L.

2. The method for recovering metallic manganese by electrolytic manganese waste slag according to claim 1, characterized in that: During the electrolysis process, the flow rate of the low-concentration manganese electrolyte is 2.5 to 5 L / min; The temperature of the electrolysis is 37-42°C.

3. The method for recovering metallic manganese by electrolytic manganese waste slag according to claim 2, characterized in that: The cathode current density of the electrolysis is 300-400A / m 2 .

4. A method for recovering metallic manganese from electrolytic manganese waste slag according to any one of claims 1 to 3, characterized in that: The electrolysis is carried out in a diaphragm electrolyzer; The diaphragm electrolyzer comprises a cell body, a false bottom, a diaphragm mold frame, a diaphragm bag, a serpentine tube, a cathode plate and an anode plate.

5. The method for recovering metallic manganese through electrolytic manganese waste slag according to claim 4, characterized in that: The diaphragm frame is made of fir wood, and a diaphragm bag is arranged on the diaphragm frame. The lower part of the diaphragm bag is hollow and divides the tank body into three parts which are connected at the lower part.

6. The method for recovering metallic manganese by electrolyzing manganese waste slag according to claim 5, characterized in that: The serpentine tube is placed on the outer wall of the electrolytic cell, and a coolant flows through the serpentine tube.

7. The method for recovering metallic manganese by electrolyzing manganese waste slag according to claim 6, characterized in that: The cathode plate is a 1Cr18Ni9Ti stainless steel plate with a thickness of 1 to 2 mm; The anode plate is a lead-antimony-tin-silver quaternary alloy plate with a thickness of 8 to 15 mm.

8. The method for recovering metallic manganese through electrolytic manganese waste slag according to claim 7, characterized in that: The percentage of each element in the lead-antimony-tin-silver quaternary alloy plate is: 98.15-98.45wt% lead, 0.2wt% antimony, 1.2-1.5wt% tin, and 0.15wt% silver.

9. The method for recovering metallic manganese through electrolytic manganese waste slag according to claim 8, characterized in that: The effective area of ​​the anode plate is 55% to 60% of the effective area of ​​the cathode plate; The anode plate is provided with grid holes.