Method for recycling valuable metal cobalt in zinc hydrometallurgy purification slag through organic acid
Through citric acid solvent and fine grinding leaching reaction technology, the cobalt in the wet zinc purification slag is efficiently recovered, solving the problem of resource waste and achieving efficient and economical cobalt recycling and comprehensive resource utilization.
Patent Information
- Application Number
- CN202411852206.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-16
- Publication Date
- 2025-03-07
AI Technical Summary
The purified slag produced during wet zinc smelting contains cobalt of the metal, which is difficult to efficiently recycle and utilize in the existing technology, resulting in waste of resources.
Citric acid is used as a solvent, and the cobalt in the wet zinc purifying residue is recovered through fine grinding and leaching reactions, and solid-liquid separation is performed using dispersant and a method of controlling pH. Finally, a cobalt-containing product is obtained by washing and hot filtration.
It realizes efficient recycling of cobalt in wet zinc smelting slag, and the Co leaching rate can reach more than 93%, providing an economical and environmentally friendly comprehensive resource utilization method.
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of recycling and utilization, and specifically relates to a method for recovering valuable metal cobalt in hydrometallurgical zinc purification slag using organic acid. Background Art
[0002] Hydrometallurgy of zinc refers to the process of dissolving zinc in zinc roasted sand or other zinc sulfide materials and zinc sulfide concentrate in aqueous solution to extract metallic zinc or zinc compounds. It is the main method of modern zinc smelting. It consists of three major links: zinc leaching, purification from acid zinc solution, and zinc electrolytic deposition. Hydrometallurgy of zinc mainly includes roasting, leaching, leachate purification and electrolytic deposition. After the zinc concentrate is roasted, the electrolytic waste liquid is used for neutral leaching to dissolve most of the zinc oxide, and the obtained slurry is separated into supernatant and underflow slurry. After the supernatant is purified, metallic zinc is produced by electrolysis and cast into ingots. The underflow slurry is subjected to acid leaching to dissolve the residual zinc oxide, and the acid leaching solution is returned to the neutral leaching; the acid leaching slag containing about 20% zinc must be further treated. It is very necessary to develop a method to recover the valuable metals in the purified slag. Summary of the invention
[0003] The object of the present invention is to provide a method for recovering valuable metal cobalt in hydrometallurgical zinc purification slag using organic acid.
[0004] The object of the present invention is achieved in that the method for recovering valuable metal cobalt from hydrometallurgical zinc purification slag with organic acid comprises pre-treatment, leaching and post-treatment steps, specifically comprising: A. Pre-treatment: 1) Grinding the organic acid recovery hydrometallurgical zinc purification slag to be treated to obtain material a; 2) Prepare a citric acid solution with a concentration of 0.6-0.8 mol / L to obtain leaching solution b for later use; B. Leaching: adding the leachate b to the material a, and then adding a dispersant to carry out stirring and leaching reaction, and separating the solid and liquid to obtain the leachate c and the leach residue d. During the leaching reaction, the pH is controlled to be 1-1.5; C. Post-treatment: The leached residue d is washed and hot filtered to obtain a cobalt-containing product.
[0005] The technical principles of the present invention are as follows: Citric acid is H 3 Cit, chemical formula is C 6 H 8 O 7 , the ionization principle is: H 3 Cit=H 2 Cit - +H + H2 Cit - =HCit 2- +H + HCit 2- =Cit 3- +H + After ionization, Co 2+ Reaction principle: 2H 2 Cit - +Co 2+ →Co[H 2 Cit － ] 2 2HCit 2- +2Co 2+ →Co 2 [HCit 2－ ] 2 2Cit 3- +3Co 2+ →Co 3 [Cit 3- ] 2 After ionization, Ni 2+ Reaction principle: 2H 2 Cit - +Ni 2+ →Ni[H 2 Cit － ] 2 2HCit 2- +2N 2+ →Ni 2 [HCit 2－ ] 2 2Cit 3- +3Ni 2+ →Ni 3 [Cit 3- ] 2 After ionization, Zn in the reaction solution 2+ Reaction principle: 2H 2 Cit - +Zn 2+ →Zn[H 2 Cit － ] 2 2HCit 2- +2Zn 2+→Zn 2 [HCit 2－ ] 2 2Cit 3- +3Zn 2+ →Zn 3 [Cit 3- ] 2 .
[0006] The method of the present invention uses weak acid to leach Co from the second-stage purification slag of hydrometallurgy, and the Co leaching rate can reach more than 93%. The present invention is applied to the field of hydrometallurgy. Compared with the active method for recovering cobalt, the method of the present invention adopts a full wet process to provide an economical and environmentally friendly method for recovering valuable metals in the hydrometallurgy purification slag, thereby achieving the purpose of comprehensive utilization of zinc ore resources. DETAILED DESCRIPTION
[0007] The present invention is further described below in conjunction with the embodiments, but the present invention is not limited in any way. Any changes or substitutions made based on the teachings of the present invention belong to the protection scope of the present invention.
[0008] The method for recovering valuable metal cobalt from hydrometallurgical zinc purification slag using organic acid in the present invention comprises pre-treatment, leaching and post-treatment steps, specifically comprising: A. Pre-treatment: 1) Grinding the organic acid recovery hydrometallurgical zinc purification slag to be treated to obtain material a; 2) Prepare a citric acid solution with a concentration of 0.6-0.8 mol / L to obtain leaching solution b for later use; B. Leaching: adding the leachate b to the material a, and then adding a dispersant to carry out stirring and leaching reaction, and separating the solid and liquid to obtain the leachate c and the leach residue d. During the leaching reaction, the pH is controlled to be 1-1.5; C. Post-treatment: The leached residue d is washed and hot filtered to obtain a cobalt-containing product.
[0009] A. The particle size of material a in step 1) is 150-250 mesh.
[0010] In step B, the liquid-to-solid volume ratio of the leaching solution b and the material a is (9~10):1.
[0011] The amount of dispersant added in step B is 1-3% of the mass of material a.
[0012] The dispersant is lignan.
[0013] The stirring speed in step B is 400~500r / min.
[0014] The leaching reaction time in step B is 100~120min.
[0015] In step B, the pH is controlled by adjusting concentrated sulfuric acid.
[0016] The washing hot filtration described in step C is performed by using hot water with a temperature of more than 80°C.
[0017] The components of the wet zinc smelting purification slag to be treated for organic acid recovery are: Co4-6%, Ni0.1-1%, Cu0.1-0.5%, Fe1-2%, Cd0.01-0.1%, As0.0005-0.001%, Ag0.001-0.002%, Al0.001-0.002%, and Zn remainder.
[0018] The present invention is further described below with specific implementation cases: Example 1 The second-stage purification slag of a company in Qujing, Yunnan was used as raw material, and the main components were: Co4.3%, Ni0.17%, Cu0.15%, Fe1.6%, Cd0.02%, As0.0001%, Ag0.0015%, Al0.0017%, and Zn remainder. After fine grinding to 200 mesh, 500g of the second-stage purification slag was taken, and 4.5L of leaching solution was prepared according to the liquid-solid ratio of 9:1, in which the concentration of citric acid was 0.6mol / L, and the amount of dispersant lignin added was 5g according to 1% of the amount of purified slag. The reaction time was 100min, and the pH was 1. After sufficient reaction, water at a temperature of 80°C was used for washing and hot filtration. The weight of the slag after the reaction was 117.3g, of which the Co content was 1.26%, and the Co leaching rate was .
[0019] Example 2 The second-stage purification slag of a company in Baoshan, Yunnan was used as raw material, and the main components were: Co5.6%, Ni0.53%, Cu0.11%, Fe1.2%, Cd0.04%, As0.0003%, Ag0.0011%, Al0.001%, and Zn remainder. After fine grinding to 200 mesh, 400g of the second-stage purification slag was taken, and 4L of leaching solution was prepared according to a liquid-solid ratio of 10:1, in which the citric acid concentration was 0.8mol / L, and the amount of dispersant lignin added was 8g according to 2% of the amount of purified slag. The reaction time was 120min, and the pH was 1.5. After sufficient reaction, water at a temperature of 85°C was used for washing and hot filtration. The weight of the slag after the reaction was 87.1g, of which the Co content was 1.43%, and the Co leaching rate was .
Claims
1. A method for recovering valuable metal cobalt from hydrometallurgical zinc purification slag using organic acid, characterized in that: The method for recovering valuable metal cobalt from hydrometallurgical zinc purification slag using organic acid comprises pre-treatment, leaching and post-treatment steps, specifically comprising: A. Pre-treatment: 1) Grinding the organic acid recovery hydrometallurgical zinc purification slag to be treated to obtain material a; 2) Prepare a citric acid solution with a concentration of 0.6-0.8 mol / L to obtain leaching solution b for later use; B. Leaching: adding the leachate b to the material a, and then adding a dispersant to carry out stirring and leaching reaction, and separating the solid and liquid to obtain the leachate c and the leach residue d. During the leaching reaction, the pH is controlled to be 1-1.5; C. Post-treatment: The leached residue d is washed and hot filtered to obtain a cobalt-containing product.
2. The method for recovering valuable metal cobalt from hydrometallurgical zinc purification slag using organic acid according to claim 1, characterized in that: A. The particle size of material a in step 1) is 150-250 mesh.
3. The method for recovering valuable metal cobalt from hydrometallurgical zinc purification slag with organic acid according to claim 1, characterized in that: In step B, the liquid-to-solid volume ratio of the leaching solution b and the material a is (9~10):
1.
4. The method for recovering valuable metal cobalt from hydrometallurgical zinc purification slag with organic acid according to claim 1, characterized in that: The amount of dispersant added in step B is 1-3% of the mass of material a.
5. The method for recovering valuable metal cobalt from hydrometallurgical zinc purification slag using organic acid according to claim 1 or 4, characterized in that: The dispersant is lignan.
6. The method for recovering valuable metal cobalt from hydrometallurgical zinc purification slag using organic acid according to claim 1, characterized in that: The stirring speed in step B is 400~500r / min.
7. The method for recovering valuable metal cobalt from hydrometallurgical zinc purification slag using organic acid according to claim 1, characterized in that: The leaching reaction time in step B is 100~120min.
8. The method for recovering valuable metal cobalt from hydrometallurgical zinc purification slag using organic acid according to claim 1, characterized in that: In step B, the pH is controlled by adjusting concentrated sulfuric acid.
9. The method for recovering valuable metal cobalt from hydrometallurgical zinc purification slag using organic acid according to claim 1, characterized in that: The washing hot filtration described in step C is performed by using hot water with a temperature of more than 80°C.
10. The method for recovering valuable metal cobalt from hydrometallurgical zinc purification slag using organic acid according to claim 1, characterized in that: The components of the wet zinc smelting purification slag to be treated for organic acid recovery are: Co4-6%, Ni0.1-1%, Cu0.1-0.5%, Fe1-2%, Cd0.01-0.1%, As0.0005-0.001%, Ag0.001-0.002%, Al0.001-0.002%, and Zn remainder.