A method for preparing manganese cobaltate by solid phase sintering of high-cobalt slag from hydrometallurgical zinc smelting

Abstract

The present invention discloses a method for preparing manganese cobaltate by solid-phase sintering of high-cobalt slag from wet zinc smelting, which belongs to the field of resource utilization of metallurgical solid waste. High-cobalt slag produced by the wet zinc smelting process is used as raw material, and after impurities are removed by alkaline leaching, solid-phase sintering is carried out in an air atmosphere; the roasted product is ball-milled to obtain solid particles containing manganese cobaltate. The method for preparing manganese cobaltate by solid-phase sintering of high-cobalt slag provided by the present invention has a short process flow and does not require the addition of other raw materials. The obtained manganese cobaltate particles have the characteristics of fine particle size and large specific surface area, thereby effectively realizing the high-value utilization of high-cobalt slag from metallurgical solid waste.

Description

Technical Field

[0001] The invention belongs to the technical field of comprehensive utilization of hydrometallurgical solid waste, and in particular relates to a method for preparing manganese cobaltate by solid-phase sintering of high-cobalt slag from hydrometallurgy zinc smelting. Background Art

[0002] Hydrometallurgy is the mainstream process for smelting zinc sulfide concentrate. During the leaching process, cobalt from the zinc sulfide concentrate enters the zinc leachate, negatively impacting subsequent electrolytic zinc production. Currently, zinc powder replacement is the most common method for purifying and removing cobalt from the leachate. By adding large amounts of zinc powder, the cobalt concentration in the leachate is reduced to below 1 mg / L. The resulting purified cobalt slag is further enriched through neutral leaching, acid leaching, and potassium permanganate oxidation precipitation to produce high-cobalt slag with a cobalt grade of up to 30%, making it an important raw material for cobalt smelting. High-cobalt slag primarily contains cobalt and manganese compounds, as well as trace amounts of zinc and cadmium. Further cobalt extraction requires separation of zinc and cobalt, as well as separation of cobalt and manganese. Acid leaching, extraction, and stripping are commonly used to obtain pure cobalt sulfate. This process is lengthy, with multiple solid-liquid and liquid-liquid conversions, resulting in low resource utilization and high costs.

[0003] Due to its excellent performance, manganese cobalt oxide has been applied and studied in the fields of battery materials, magnetic materials, thermosensitive materials, and adsorption materials. Existing methods and research on the preparation of manganese cobalt oxide are mainly based on wet synthesis processes, such as the solvothermal method. This type of method usually involves mixing metal salts of cobalt and manganese with a precipitant such as urea in an alcohol solution (generally a mixed solution of ethylene glycol and water), stirring evenly, and then sealing in a reactor for a solvothermal reaction. After separation, a cobalt-manganese precursor is obtained, which is then calcined to obtain the manganese cobalt oxide product. The disadvantages of this method are long processes, complex operations, low production efficiency of manganese cobalt oxide, and product quality affected by various factors. Summary of the Invention

[0004] In view of the current status of recycling high-cobalt slag with cobalt-manganese compounds as the main component produced in the hydrometallurgical zinc smelting process, the present invention provides a method for preparing manganese cobaltate by solid-phase sintering of high-cobalt slag from hydrometallurgical zinc smelting. Using metallurgical solid waste high-cobalt slag as raw material, through alkaline leaching to remove impurities, solid-phase roasting, ball milling and other processes, a high-specific surface area, nano-sized manganese cobaltate material is obtained, which can effectively achieve high-value utilization of high-cobalt slag.

[0005] The present invention provides a method for preparing manganese cobalt oxide by solid-phase sintering of high-cobalt slag from hydrometallurgy zinc smelting, which mainly comprises the following steps:

[0006] Step 1: Wash the high-cobalt slag with water, dry it, and sieve it;

[0007] Step 2: using an alkaline solution to leach and remove impurities from the high-cobalt slag to obtain leached slag and leachate;

[0008] Step 3: pressing the leached residue into tablets and then roasting them in an air atmosphere to obtain a roasted product;

[0009] Step 4: crushing and ball-milling the calcined product to obtain granular manganese cobalt oxide material.

[0010] Furthermore, the high-cobalt slag described in step 1 is a high-grade cobalt slag obtained by further enriching the zinc leaching solution in the hydrometallurgical zinc smelting process except for the cobalt slag, wherein the cobalt content is 20-30wt.%, and the manganese content is 15-25wt.%.

[0011] Furthermore, the alkaline solution described in step 2 is a single solution or a mixed solution of NaOH, KOH, and NH4OH, with a concentration of 2 to 6 mol / L, and the leaching conditions are 50 to 90°C, a liquid-solid ratio of 10 to 40 mL / g, and a time of 30 to 90 min.

[0012] Furthermore, the leachate in step 2 can be sent to a zinc and cadmium recovery process for recovery.

[0013] Furthermore, the calcination conditions in step 3 are: calcination temperature of 600-1200° C., and calcination time of 60-180 min.

[0014] Furthermore, the crushing and ball milling conditions of the calcined product described in step 4 are as follows: the mass ratio of the calcined product to the abrasive is 1:20 to 1:100, the abrasive is a steel ball, the diameters of the steel balls are 12, 10, and 8 mm, respectively, the mass ratio is 3:4:3, the ball milling time is 30 to 90 min, and the rotation speed is 200 rpm to 800 rpm.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. The present invention uses alkaline leaching to remove impurities and solid-phase roasting to recycle high-cobalt slag, without the need for multi-stage acid leaching, oxidation precipitation, extraction and other processes. It has less solid-liquid conversion, simple and clean process, low cost and wide application range.

[0017] 2. Based on the differences in properties between zinc and cadmium compounds and cobalt and manganese compounds, the present invention uses an alkaline solution to remove impurities from high-cobalt slag, thereby reducing the zinc and cadmium contents in the high-cobalt slag and improving the cobalt and manganese qualities in the high-cobalt slag. Furthermore, through roasting and ball milling, the phase, morphology and particle size of manganese cobaltate are regulated to obtain high-quality spinel manganese cobaltate material. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a process flow chart of the present invention;

[0019] Figure 2 Phase analysis results of manganese cobalt oxide prepared in Example 1;

[0020] Figure 3 These are the SEM-EDS analysis results of the manganese cobalt oxide prepared in Example 1. DETAILED DESCRIPTION

[0021] The specific technical implementation scheme of the present invention is further described below through examples and drawings.

[0022] The present invention provides a method for preparing manganese cobalt oxide by solid phase sintering of high cobalt slag from hydrometallurgical zinc smelting. The process flow is as follows: Figure 1 shown.

[0023] The embodiment of the present invention uses high-cobalt slag produced by a hydrometallurgical zinc smelting enterprise in Henan Province. The high-cobalt slag mainly contains elements such as cobalt, manganese, zinc, and cadmium. The contents of cobalt, manganese, zinc, and cadmium are 22.01wt.%, 19.64wt.%, 6.19wt.%, and 3.41wt.%, respectively.

[0024] The roasting equipment in the embodiment of the present invention includes but is not limited to roasting rotary kilns, boiling furnaces and other equipment that can heat high-cobalt slag.

[0025] The ball milling equipment in the embodiment of the present invention includes but is not limited to planetary high-energy ball mills and other equipment that can crush and grind the calcined product.

[0026] Example 1

[0027] This embodiment relates to a method for preparing manganese cobalt oxide by solid-phase sintering of high-cobalt slag from hydrometallurgical zinc smelting, and the specific steps are as follows:

[0028] Step 1: Wash the high-cobalt slag with industrial water at a liquid-to-solid ratio of 20:1, a temperature of 90°C, and a stirring speed of 400 rpm for 120 minutes to remove soluble sulfate;

[0029] Step 2: After washing with water, the filter cake is filtered and dried at 100°C for 120 minutes. After being completely dried, the filter cake is sieved using a 200-mesh standard test sieve to obtain a washed high-cobalt slag;

[0030] Step 3: Take the washed high-cobalt slag from step 2 and leach it in a 4 mL / g NaOH solution to remove zinc and cadmium elements. The leaching solution temperature is 90° C., the liquid-solid ratio is 40 mL / g, the stirring speed is 300 rpm, and the time is 60 min;

[0031] Step 4: Take 8 g of the alkaline leaching residue from step 3 and use a fully automatic tablet press to compress it under the conditions of a pressure of 5t and a pressure holding time of 10s to obtain a columnar roasted sample;

[0032] Step 5: Place the calcined sample from step 4 on a corundum porcelain boat, place it in a tube furnace, and heat it to 800°C at a rate of 5°C / min in an air atmosphere. Calcinate for 90 minutes, and cool the calcined product in the furnace.

[0033] Step 6: The calcined product of step 5 was crushed and refined using a planetary high-energy ball mill with a ball-to-material ratio of 20:1 (steel balls with diameters of 12, 10, and 8 mm, respectively, and a mass ratio of 3:4:3), a ball mill speed of 600 rpm, and a time of 60 min to obtain granular manganese cobalt oxide material. The product XRD and SEM-EDS were as follows: Figure 2 、 Figure 3 As shown. XRD analysis confirmed that the obtained product is spinel manganese cobalt oxide. SEM images show that the product particles are small, reaching the nanometer level. High-magnification results show that the fine particles have a polyhedral appearance. In addition, EDS results also confirm that the metal elements manganese, cobalt, zinc, and cadmium are very evenly distributed in the obtained manganese cobalt oxide material.

[0034] Example 2

[0035] This embodiment relates to a method for preparing manganese cobalt oxide by solid-phase sintering of high-cobalt slag from hydrometallurgical zinc smelting, and the specific steps are as follows:

[0036] Step 1: Wash the high-cobalt slag with industrial water at a liquid-to-solid ratio of 20:1, a temperature of 90°C, and a stirring speed of 400 rpm for 120 minutes to remove soluble sulfate;

[0037] Step 2: After washing with water, the filter cake is filtered and dried at 100°C for 120 minutes. After being completely dried, the filter cake is sieved using a 200-mesh standard test sieve to obtain a washed high-cobalt slag;

[0038] Step 3: Take the water-washed high-cobalt slag from step 2 and leach it in a 6 mL / g NaOH solution to remove zinc and cadmium elements. The leaching solution temperature is 90° C., the liquid-solid ratio is 40 mL / g, the stirring speed is 300 rpm, and the time is 90 min;

[0039] Step 4: Take 8 g of the alkaline leaching residue from step 3 and use a fully automatic tablet press to compress it under the conditions of a pressure of 5t and a pressure holding time of 10s to obtain a columnar roasted sample;

[0040] Step 5: Place the calcined sample from step 4 on a corundum boat, place it in a tube furnace, and heat it to 600°C at a rate of 5°C / min in an air atmosphere. Calcinate for 60 minutes, and cool the calcined product in the furnace.

[0041] Step 6: The calcined product of step 5 is crushed and refined using a planetary high-energy ball mill with a ball-to-material ratio of 100:1 (the diameters of the steel balls are 12, 10, and 8 mm, respectively, and the mass ratio is 3:4:3), a ball mill speed of 200 rpm, and a time of 30 min to obtain a granular manganese cobalt oxide material.

[0042] Example 3

[0043] This embodiment relates to a method for preparing manganese cobalt oxide by solid-phase sintering of high-cobalt slag from hydrometallurgical zinc smelting, and the specific steps are as follows:

[0044] Step 1: Wash the high-cobalt slag with industrial water at a liquid-to-solid ratio of 20:1, a temperature of 90°C, and a stirring speed of 400 rpm for 120 minutes to remove soluble sulfate;

[0045] Step 2: After washing with water, the filter cake is filtered and dried at 100°C for 120 minutes. After being completely dried, the filter cake is sieved using a 200-mesh standard test sieve to obtain a washed high-cobalt slag;

[0046] Step 3: Take the washed high-cobalt slag from step 2 and leach it in a 6 mL / g KOH solution to remove zinc and cadmium elements. The leaching solution temperature is 90° C., the liquid-solid ratio is 40 mL / g, the stirring speed is 300 rpm, and the time is 90 min;

[0047] Step 4: Take 8 g of the alkaline leaching residue from step 3 and use a fully automatic tablet press to compress it under the conditions of a pressure of 5t and a pressure holding time of 10s to obtain a columnar roasted sample;

[0048] Step 5: Place the calcined sample from step 4 on a corundum boat, place it in a tube furnace, and heat it to 600°C at a rate of 5°C / min in an air atmosphere. Calcinate for 60 minutes, and cool the calcined product in the furnace.

[0049] Step 6: The calcined product of step 5 is crushed and refined using a planetary high-energy ball mill with a ball-to-material ratio of 100:1 (the diameters of the steel balls are 12, 10, and 8 mm, respectively, and the mass ratio is 3:4:3), a ball mill speed of 200 rpm, and a time of 30 min to obtain a granular manganese cobalt oxide material.

[0050] Example 4

[0051] This embodiment relates to a method for preparing manganese cobalt oxide by solid-phase sintering of high-cobalt slag from hydrometallurgical zinc smelting, and the specific steps are as follows:

[0052] Step 1: Wash the high-cobalt slag with industrial water at a liquid-to-solid ratio of 20:1, a temperature of 90°C, and a stirring speed of 400 rpm for 120 minutes to remove soluble sulfate;

[0053] Step 2: After washing with water, the filter cake is filtered and dried at 100°C for 120 minutes. After being completely dried, the filter cake is sieved using a 200-mesh standard test sieve to obtain a washed high-cobalt slag;

[0054] Step 3: Take the water-washed high-cobalt slag from step 2 and leach it in a 6 mL / g NH4OH solution to remove zinc and cadmium elements. The leaching solution temperature is 90°C, the liquid-solid ratio is 40 mL / g, the stirring speed is 300 rpm, and the time is 90 min;

[0055] Step 4: Take 8 g of the alkaline leaching residue from step 3 and use a fully automatic tablet press to compress it under the conditions of a pressure of 5t and a pressure holding time of 10s to obtain a columnar roasted sample;

[0056] Step 5: Place the calcined sample from step 4 on a corundum boat, place it in a tube furnace, and heat it to 600°C at a rate of 5°C / min in an air atmosphere. Calcinate for 60 minutes, and cool the calcined product in the furnace.

[0057] Step 6: The calcined product of step 5 is crushed and refined using a planetary high-energy ball mill with a ball-to-material ratio of 100:1 (the diameters of the steel balls are 12, 10, and 8 mm, respectively, and the mass ratio is 3:4:3), a ball mill speed of 200 rpm, and a time of 30 min to obtain a granular manganese cobalt oxide material.

[0058] Example 5

[0059] This embodiment relates to a method for preparing manganese cobalt oxide by solid-phase sintering of high-cobalt slag from hydrometallurgical zinc smelting, and the specific steps are as follows:

[0060] Step 1: Wash the high-cobalt slag with industrial water at a liquid-to-solid ratio of 20:1, a temperature of 90°C, and a stirring speed of 400 rpm for 120 minutes to remove soluble sulfate;

[0061] Step 2: After washing with water, the filter cake is filtered and dried at 100°C for 120 minutes. After being completely dried, the filter cake is sieved using a 200-mesh standard test sieve to obtain a washed high-cobalt slag;

[0062] Step 3: Take the washed high-cobalt slag from step 2 and leach it into a 6 mL / g NaOH-KOH-NH4OH mixed solution to remove zinc and cadmium elements. The leaching temperature is 90°C, the liquid-solid ratio is 40 mL / g, the stirring speed is 300 rpm, and the time is 90 min;

[0063] Step 4: Take 8 g of the alkaline leaching residue from step 3 and use a fully automatic tablet press to compress it under the conditions of a pressure of 5t and a pressure holding time of 10s to obtain a columnar roasted sample;

[0064] Step 5: Place the calcined sample from step 4 on a corundum boat, place it in a tube furnace, and heat it to 600°C at a rate of 5°C / min in an air atmosphere. Calcinate for 60 minutes, and cool the calcined product in the furnace.

[0065] Step 6: The calcined product of step 5 is crushed and refined using a planetary high-energy ball mill with a ball-to-material ratio of 100:1 (the diameters of the steel balls are 12, 10, and 8 mm, respectively, and the mass ratio is 3:4:3), a ball mill speed of 200 rpm, and a time of 30 min to obtain a granular manganese cobalt oxide material.

[0066] Example 6

[0067] This embodiment relates to a method for preparing manganese cobalt oxide by solid-phase sintering of high-cobalt slag from hydrometallurgical zinc smelting, and the specific steps are as follows:

[0068] Step 1: Wash the high-cobalt slag with industrial water at a liquid-to-solid ratio of 20:1, a temperature of 90°C, and a stirring speed of 400 rpm for 120 minutes to remove soluble sulfate;

[0069] Step 2: After washing with water, the filter cake is filtered and dried at 100°C for 120 minutes. After being completely dried, the filter cake is sieved using a 200-mesh standard test sieve to obtain a washed high-cobalt slag;

[0070] Step 3: Take the washed high-cobalt slag from step 2 and leach it in a 2 mL / g NaOH solution to remove zinc and cadmium elements. The leaching solution temperature is 50° C., the liquid-to-solid ratio is 10 mL / g, the stirring speed is 300 rpm, and the time is 30 min.

[0071] Step 4: Take 8 g of the alkaline leaching residue from step 3 and use a fully automatic tablet press to compress it under the conditions of a pressure of 5t and a pressure holding time of 10s to obtain a columnar roasted sample;

[0072] Step 5: Place the calcined sample from step 4 on a corundum boat, place it in a tube furnace, and heat it to 600°C at a rate of 5°C / min in an air atmosphere. Calcinate for 60 minutes, and cool the calcined product in the furnace.

[0073] Step 6: The calcined product of step 5 is crushed and refined using a planetary high-energy ball mill with a ball-to-material ratio of 100:1 (the diameters of the steel balls are 12, 10, and 8 mm, respectively, and the mass ratio is 3:4:3), a ball mill speed of 200 rpm, and a time of 30 min to obtain a granular manganese cobalt oxide material.

[0074] Example 7

[0075] This embodiment relates to a method for preparing manganese cobalt oxide by solid-phase sintering of high-cobalt slag from hydrometallurgical zinc smelting, and the specific steps are as follows:

[0076] Step 1: Wash the high-cobalt slag with industrial water at a liquid-to-solid ratio of 20:1, a temperature of 90°C, and a stirring speed of 400 rpm for 120 minutes to remove soluble sulfate;

[0077] Step 2: After washing with water, the filter cake is filtered and dried at 100°C for 120 minutes. After being completely dried, the filter cake is sieved using a 200-mesh standard test sieve to obtain a washed high-cobalt slag;

[0078] Step 3: Take the water-washed high-cobalt slag from step 2 and leach it in a 6 mL / g NaOH solution to remove zinc and cadmium elements. The leaching solution temperature is 90° C., the liquid-solid ratio is 40 mL / g, the stirring speed is 300 rpm, and the time is 90 min;

[0079] Step 4: Take 8 g of the alkaline leaching residue from step 3 and use a fully automatic tablet press to compress it under the conditions of a pressure of 5t and a pressure holding time of 10s to obtain a columnar roasted sample;

[0080] Step 5: Place the calcined sample from step 4 on a corundum boat, place it in a tube furnace, and heat it to 1200°C at a rate of 5°C / min in an air atmosphere. Calcinate for 180 min, and cool the calcined product in the furnace.

[0081] Step 6: The calcined product of step 5 is crushed and refined using a planetary high-energy ball mill with a ball-to-material ratio of 100:1 (the diameters of the steel balls are 12, 10, and 8 mm, respectively, and the mass ratio is 3:4:3), a ball mill speed of 200 rpm, and a time of 30 min to obtain a granular manganese cobalt oxide material.

[0082] Example 8

[0083] This embodiment relates to a method for preparing manganese cobalt oxide by solid-phase sintering of high-cobalt slag from hydrometallurgical zinc smelting, and the specific steps are as follows:

[0084] Step 1: Wash the high-cobalt slag with industrial water at a liquid-to-solid ratio of 20:1, a temperature of 90°C, and a stirring speed of 400 rpm for 120 minutes to remove soluble sulfate;

[0085] Step 2: After washing with water, the filter cake is filtered and dried at 100°C for 120 minutes. After being completely dried, the filter cake is sieved using a 200-mesh standard test sieve to obtain a washed high-cobalt slag;

[0086] Step 3: Take the water-washed high-cobalt slag from step 2 and leach it in a 6 mL / g NaOH solution to remove zinc and cadmium elements. The leaching solution temperature is 90° C., the liquid-solid ratio is 40 mL / g, the stirring speed is 300 rpm, and the time is 90 min;

[0087] Step 4: Take 8 g of the alkaline leaching residue from step 3 and use a fully automatic tablet press to compress it under the conditions of a pressure of 5t and a pressure holding time of 10s to obtain a columnar roasted sample;

[0088] Step 5: Place the calcined sample from step 4 on a corundum boat, place it in a tube furnace, and heat it to 1200°C at a rate of 5°C / min in an air atmosphere. Calcinate for 180 min, and cool the calcined product in the furnace.

[0089] Step 6: The calcined product of step 5 was crushed and refined using a planetary high-energy ball mill with a ball-to-material ratio of 20:1 (steel ball diameters of 12, 10, and 8 mm, respectively, and a mass ratio of 3:4:3), a ball mill speed of 800 rpm, and a time of 90 min to obtain granular manganese cobalt oxide material.

[0090] The above content is a further detailed description of the present invention in conjunction with specific embodiments, and the specific implementation of the present invention should not be considered to be limited to these descriptions. For those skilled in the art of the present invention, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should be considered to fall within the scope of protection of the present invention.

Claims

1. A method for preparing manganese cobalt oxide by solid phase sintering of high-cobalt slag from hydrometallurgy zinc smelting, characterized in that: The main steps include: Step 1: Washing high-cobalt slag, drying it, and screening it. The high-cobalt slag is high-grade cobalt slag obtained by further enriching the zinc leachate in the hydrometallurgical zinc smelting process after removing cobalt slag, wherein the cobalt content is 20-30 wt.%, and the manganese content is 15-25 wt.%; Step 2: using an alkaline solution to leach and remove impurities from the high-cobalt slag to obtain leached slag and leachate; Step 3: pressing the leached residue into tablets and then roasting them in an air atmosphere to obtain a roasted product; Step 4: crushing and ball-milling the calcined product to obtain granular manganese cobalt oxide material.

2. The method for preparing manganese cobaltate by solid phase sintering of high-cobalt slag from hydrozincification according to claim 1, characterized in that: The alkaline solution described in step 2 is a single solution or a mixed solution of NaOH, KOH, and NH4OH, with a concentration of 2-6 mol / L, and the leaching conditions are 50-90°C, a liquid-solid ratio of 10-40 mL / g, and a time of 30-90 min.

3. The method for preparing manganese cobaltate by solid phase sintering of high-cobalt slag from hydrozincification according to claim 1, characterized in that: The leachate in step 2 can be sent to the zinc and cadmium recovery process for recovery.

4. The method for preparing manganese cobaltate by solid phase sintering of high-cobalt slag from hydrozincification according to claim 1, characterized in that: The calcination conditions described in step 3 are: calcination temperature of 600-1200° C., and calcination time of 60-180 min.

5. The method for preparing manganese cobalt oxide by solid phase sintering of high-cobalt slag from hydrometallurgy according to claim 1, characterized in that: The crushing and ball milling conditions of the calcined product described in step 4 are as follows: the mass ratio of the calcined product to the abrasive is 1: 20~1: 100, the abrasive is steel balls, the diameters of the steel balls are 12, 10, and 8 mm, respectively, the mass ratio is 3: 4: 3, the ball milling time is 30~90 min, and the rotation speed is 200 rpm~800 rpm.

Images