Method for removing silicon from acidic manganese sulfate solution
By converting silicon impurities into silicon-containing heteropolyacids in manganese sulfate solution and using acid-neutral synergistic extraction agent for extraction and separation, the problems of complex silicon removal process and large wastewater in the prior art were solved, and efficient and stable silicon removal effect was achieved.
Patent Information
- Application Number
- CN202510379061.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-28
- Publication Date
- 2025-05-13
AI Technical Summary
When removing silicon from manganese sulfate solution, the prior art has complicated processes and large wastewater yields, which is not conducive to environmental protection and application.
By adjusting the H+ concentration of the manganese sulfate solution, the silicon impurities are converted into silicon-containing heteropolyacids, and the extraction and separation are used to perform extraction and separation, so as to achieve efficient removal of silicon.
This method can reduce the silicon content in the manganese sulfate solution from 15 to 35 mg/L to below 2.0 mg/L, and has excellent deep silicon removal effect, simple operation and low drug cost.
Smart Images
Figure CN119976974A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a method for removing silicon from an acidic manganese sulfate solution, belonging to the technical field of chemical extraction. Background Art
[0002] Manganese sulfate is one of the main products in the manganese salt series. With the rapid development of the new energy battery industry, the demand for manganese sulfate-related products for lithium-ion battery positive electrode materials is increasing day by day, and the requirements for their impurity content are also getting higher and higher.
[0003] The manganese sulfate solution obtained by hydrometallurgy contains impurities such as iron, cobalt, calcium, magnesium, lead, zinc, and silicon. Precipitation and extraction methods are usually used to remove impurities such as iron, cobalt, calcium, magnesium, lead, and zinc. However, there is no mature and simple treatment process for the impurity silicon. The silicon content in the manganese sulfate solution system is generally maintained at 15-35 mg / L.
[0004] In the prior art, the commonly used resin adsorption desiliconization method requires the use of a large amount of acid, pure water, and alkali solution to desorb, clean, and regenerate the resin. The process is complicated and produces a large amount of wastewater, which is not conducive to environmental protection and application. Summary of the invention
[0005] The object of the present invention is to provide a method for removing silicon from an acidic manganese sulfate solution. The method transforms silicon impurities in the manganese sulfate solution into silicon-containing heteropolyacids, and then uses a special acid-neutral synergistic extractant to achieve efficient extraction and separation of the silicon-containing heteropolyacids. The method has the advantages of simple operation, stable silicon removal effect, low reagent cost, etc.
[0006] In order to achieve the above technical purpose, the present invention provides a method for removing silicon from an acidic manganese sulfate solution, the method comprising: removing H from the manganese sulfate solution containing silicon impurities; + After the concentration is adjusted to 1.0-2.0 mol / L, a hybridizing agent is added to perform hybridization reaction with silicon impurities to form a silicon-containing heteropoly acid, thereby obtaining a manganese sulfate solution containing silicon-containing heteropoly acid, wherein the manganese sulfate solution containing silicon-containing heteropoly acid is extracted and separated using an organic phase containing an acidic-neutral synergistic extractant, and the raffinate is the desiliconized liquid;
[0007] The acid-neutral synergistic extractant consists of an acidic extractant and a neutral extractant; the acidic extractant includes at least one of P204, P507, and naphthalenesulfonic acid; and the neutral extractant includes at least one of isooctyl alcohol, isopentanol, and TBP.
[0008] The components of the manganese sulfate solution containing silicon impurities of the present invention include: Mn 30-110g / L, Si 15-35mg / L, Co≤200mg / L, Ca≤30mg / L, and Mg≤30mg / L.
[0009] The method for removing silicon from an acidic manganese sulfate solution provided by the present invention has the key of first using a hybridizing agent to chemically transform silicate impurities, controlling an appropriate acidic environment, and reacting the hybridizing agent with silicate impurities to transform into silicon-containing heteropolyacids. In view of the physicochemical characteristics of silicon-containing heteropolyacids, the present invention innovatively proposes to use an acidic-neutral synergistic extractant to extract and separate silicon-containing heteropolyacids from the manganese sulfate solution. The acidic-neutral synergistic extractant is mainly composed of an acidic extractant such as P204 and a neutral extractant such as isooctyl alcohol. Compared with a single acidic or neutral extractant, the extraction effect of the acid-containing heteropolyacid on the silicon-containing heteropolyacid is significantly improved, and the silicon impurities in the acidic manganese sulfate solution can be deeply purified.
[0010] As a preferred solution, the molar ratio of the acidic extractant to the neutral extractant in the acid-neutral synergistic extractant is 1: 1 to 3: 1. If the acidic extractant ratio is low, the silicon removal rate is poor, and if the acidic extractant ratio is high, the manganese co-extraction rate will increase, resulting in increased manganese loss.
[0011] As a preferred solution, the hybridizing agent includes molybdate and / or tungstate. The preferred hybridizing agent can convert silicate into molybdenum silicopoly acid and tungstosilicopoly acid, respectively.
[0012] As a preferred solution, the amount of the hybridizing agent added is 0.5 to 5 times the molar amount of silicon impurities in the manganese sulfate solution containing silicon impurities. Different ratios of hybridizing agent to silicon impurities will produce different stabilities of heteropolyacids, which will affect the removal effect of silicon impurities. The amount of the hybridizing agent added is controlled within a preferred range, which can ensure that silicate is converted into stable heteropolyacids, which is beneficial to subsequent extraction and separation.
[0013] As a preferred solution, the hybridization reaction conditions are: reaction time of 30 to 60 minutes at room temperature.
[0014] As a preferred solution, the volume proportion of the acidic-neutral synergistic extractant in the organic phase is 25-50%. If the proportion of the acidic-neutral synergistic extractant in the organic phase is too low, the extraction efficiency is low and the required organic phase ratio is increased, while if the proportion of the acidic-neutral synergistic extractant in the organic phase is too high, the extractant is difficult to fully dissolve and disperse to exert its extraction effect.
[0015] As a preferred solution, the organic phase contains a diluent; the diluent includes light white oil.
[0016] As a preferred solution, the extraction conditions are: the extraction level is 1 to 5, and the O / A ratio is 1:1 to 3:1.
[0017] As a preferred solution, the silicon-loaded organic phase obtained by the extraction and separation is back-extracted with an aqueous ammonia solution, and the regenerated organic phase is returned to the extraction section.
[0018] As a preferred solution, the pH of the ammonia solution is 12-14; the stripping conditions are: the number of stages is 1-5, and the O / A ratio is 1:10-1:20.
[0019] Compared with the prior art, the technical solution of the present invention has the following beneficial technical effects:
[0020] The method for removing silicon from an acidic manganese sulfate solution provided by the present invention can reduce the silicon content in the manganese sulfate solution from 15 to 35 mg / L to below 2.0 mg / L, and has an excellent deep silicon removal effect.
[0021] The method for removing silicon from an acidic manganese sulfate solution provided by the invention has the advantages of simple operation, low reagent consumption, stable silicon removal effect, and the like. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.
[0023] Figure 1 The present invention is a schematic diagram of the process of removing silicon from an acidic manganese sulfate solution. DETAILED DESCRIPTION
[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of this application; the terms used in the specification of the application herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, not to describe a specific order.
[0025] Example 1
[0026] This example serves as a comparative example.
[0027] In manganese sulfate solution, manganese: 53.67 g / L, silicon: 28.62 mg / L.
[0028] Silicon removal steps:
[0029] 1. Add sulfuric acid to adjust the H of the manganese sulfate solution. + The concentration is 1.0 mol / L.
[0030] 2. Add molybdate in a molar amount of 0.5 times the molar amount of silicon, and the hybridization time is 30 minutes.
[0031] 3. A single acidic extractant or a neutral extractant was prepared at a volume concentration of 20%, and light white oil was used as a diluent to prepare an organic phase, and a single-stage extraction was performed with the aqueous phase at a ratio of O / A=1:1 to investigate the effect of a single extractant on silicon removal. The results showed that a single acidic extractant had no effect on silicon removal, and although a single neutral extractant had a silicon removal effect, the removal rate was less than 60%, and the silicon removal depth was insufficient.
[0032]
[0033] Example 2
[0034] Preparation of synergistic extractant: P204 and isooctyl alcohol are mixed in a ratio of 1:1 to prepare a synergistic extractant.
[0035] In manganese sulfate solution, manganese: 50.67 g / L, silicon: 21.19 mg / L.
[0036] Silicon removal steps:
[0037] 1. Add sulfuric acid to adjust the H of the manganese sulfate solution. + The concentration is 1.0 mol / L.
[0038] 2. Add molybdate in a molar amount of 0.5 times the molar amount of silicon, and the hybridization time is 30 minutes.
[0039] 3. The synergistic extractant and light white oil were mixed in a volume ratio of 1:1 as the organic phase, and three-stage extraction was performed with the aqueous phase at O / A=1:1. Silicon entered the organic phase, and the raffinate was the purified silicon-removing liquid, with manganese: 50.54 g / L, silicon: 1.54 mg / L.
[0040] 4. The silicon-containing organic phase is subjected to secondary stripping with an ammonia solution of pH=13 at an O / A=1:10. After stripping, the silicon content in the organic phase is 0.05 mg / L and is returned to the extraction section.
[0041] Example 3
[0042] Preparation of synergistic extractant: P507 and isoamyl alcohol were mixed in a ratio of 2:1 to prepare a synergistic extractant.
[0043] In manganese sulfate solution, manganese: 50.88g / L, silicon: 31.58mg / L.
[0044] Silicon removal steps:
[0045] 1. Add sulfuric acid to adjust the H of the manganese sulfate solution.+ The concentration is 1.5mol / L.
[0046] 2. Add molybdate in a molar amount twice that of silicon and the hybridization time is 45 minutes.
[0047] 3. Mix the synergistic extractant and light white oil in a volume ratio of 1:1 as the organic phase, and perform three-stage extraction with the aqueous phase at O / A=1:1. Silicon enters the organic phase, and the raffinate is the purified silicon removal liquid, with manganese: 50.61g / L, silicon: 1.92mg / L;
[0048] 4. The silicon-containing organic phase is subjected to secondary stripping with an ammonia solution of pH=13 at an O / A=1:10. After stripping, the silicon content in the organic phase is 0.06 mg / L and is returned to the extraction section.
[0049] Example 4
[0050] Preparation of synergistic extractant: Naphthalenesulfonic acid and TBP were mixed in a ratio of 3:1 to prepare a synergistic extractant.
[0051] In manganese sulfate solution, manganese: 79.88g / L, silicon: 27.79mg / L.
[0052] Silicon removal steps:
[0053] 1. Add sulfuric acid to adjust the H of the manganese sulfate solution. + The concentration is 2mol / L.
[0054] 2. Add molybdate in a molar amount three times that of silicon and the hybridization time is 45 minutes.
[0055] 3. Mix the synergistic extractant and light white oil in a volume ratio of 1:3 as the organic phase, and perform 5-stage extraction with the aqueous phase at O / A=1:1. Silicon enters the organic phase, and the raffinate is the purified silicon-removing liquid, with manganese: 78.54g / L, silicon: 1.86mg / L.
[0056] 4. The silicon-containing organic phase is stripped in five stages with an ammonia solution of pH=13 at an O / A=1:20. After stripping, the silicon content in the organic phase is 0.05 mg / L and it is returned to the extraction section.
[0057] Example 5
[0058] Preparation of synergistic extractant: P204 and TBP were mixed in a ratio of 1:1 to prepare a synergistic extractant.
[0059] In manganese sulfate solution, manganese: 105.96 g / L, silicon: 25.44 mg / L.
[0060] Silicon removal steps:
[0061] 1. Add sulfuric acid to adjust the H of the manganese sulfate solution. + The concentration is 1.2mol / L.
[0062] 2. Add molybdate in a molar amount 5 times the molar amount of silicon, and the hybridization time is 45 minutes.
[0063] 3. The synergistic extractant and light white oil were mixed in a volume ratio of 1:1 as the organic phase, and four-stage extraction was performed with the aqueous phase at O / A=1:1. Silicon entered the organic phase, and the raffinate was the purified silicon-removing liquid, with manganese: 103.74 g / L, silicon: 1.49 mg / L.
[0064] 4. The silicon-containing organic phase is subjected to secondary stripping with an ammonia solution of pH=13 at an O / A=1:20. After stripping, the silicon content in the organic phase is 0.06 mg / L and is returned to the extraction section.
[0065] Example 6
[0066] Preparation of synergistic extractant: P507 and isooctyl alcohol were mixed in a ratio of 1:1 to prepare a synergistic extractant.
[0067] In manganese sulfate solution, manganese: 93.49g / L, silicon: 31.58mg / L.
[0068] Silicon removal steps:
[0069] 1. Add sulfuric acid to adjust the H of the manganese sulfate solution. + The concentration is 1.8mol / L.
[0070] 2. Add molybdate in a molar amount three times that of silicon and the hybridization time is 50 minutes.
[0071] 3. Mix the synergistic extractant and light white oil in a volume ratio of 1:2 as the organic phase, and perform 4-stage extraction with the aqueous phase at O / A=1:1. Silicon enters the organic phase, and the raffinate is the purified silicon-removing liquid, with manganese: 92.45g / L, silicon: 1.87mg / L.
[0072] 4. The silicon-containing organic phase is stripped in three stages with an ammonia solution of pH=13 at an O / A=1:18. After stripping, the silicon content in the organic phase is 0.06 mg / L and is returned to the extraction section.
[0073] Example 7
[0074] Preparation of synergistic extractant: Naphthalenesulfonic acid and isoamyl alcohol are mixed in a ratio of 2:1 to prepare a synergistic extractant.
[0075] In manganese sulfate solution, manganese: 62.46g / L, silicon: 32.48mg / L.
[0076] Silicon removal steps:
[0077] 1. Add sulfuric acid to adjust the H of the manganese sulfate solution. + The concentration is 1.4 mol / L.
[0078] 2. Add molybdate in a molar amount 4 times the molar amount of silicon, and the hybridization time is 35 minutes.
[0079] 3. Mix the synergistic extractant and light white oil in a volume ratio of 1:1 as the organic phase, and perform three-stage extraction with the aqueous phase at O / A=1:1. Silicon enters the organic phase, and the raffinate is the purified silicon-removing liquid, with manganese: 61.08 g / L, silicon: 1.67 mg / L.
[0080] 4. The silicon-containing organic phase is stripped in three stages with an ammonia solution of pH=13 at an O / A=1:15. After stripping, the silicon content in the organic phase is 0.05 mg / L and is returned to the extraction section.
[0081] The above examples demonstrate the synergistic extractant of the present invention and its specific implementation method for removing silicon from an acidic manganese sulfate solution, and verify the advantages of the method such as simple process operation, high degree of automation, and stable silicon removal effect.
[0082] In summary, the above technical solutions of the present invention are only preferred embodiments of the present invention, and the patent scope of the present invention is not limited thereto. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.
Claims
1. A method for removing silicon from an acidic manganese sulfate solution, characterized in that: The H of manganese sulfate solution containing silicon impurities + After the concentration is adjusted to 1.0-2.0 mol / L, a hybridizing agent is added to perform hybridization reaction with silicon impurities to form a silicon-containing heteropoly acid, thereby obtaining a manganese sulfate solution containing silicon-containing heteropoly acid, wherein the manganese sulfate solution containing silicon-containing heteropoly acid is extracted and separated using an organic phase containing an acidic-neutral synergistic extractant, and the raffinate is the desiliconized liquid; The acid-neutral synergistic extractant consists of an acidic extractant and a neutral extractant; the acidic extractant includes at least one of P204, P507, and naphthalenesulfonic acid; and the neutral extractant includes at least one of isooctyl alcohol, isopentanol, and TBP.
2. A method for removing silicon from an acidic manganese sulfate solution according to claim 1, characterized in that: The molar ratio of the acidic extractant to the neutral extractant in the acidic-neutral synergistic extractant is 1:1 to 3:
1.
3. A method for removing silicon from an acidic manganese sulfate solution according to claim 1 or 2, characterized in that: The hybridizing agent includes molybdate and / or tungstate.
4. A method for removing silicon from an acidic manganese sulfate solution according to claim 3, characterized in that: The amount of the hybridizing agent added is 0.5 to 5 times the molar amount of silicon impurities in the manganese sulfate solution containing silicon impurities.
5. A method for removing silicon from an acidic manganese sulfate solution according to claim 1, 2 or 4, characterized in that: The conditions of the hybridization reaction are: reaction at room temperature for 30 to 60 minutes.
6. A method for removing silicon from an acidic manganese sulfate solution according to claim 1 or 2, characterized in that: The volume proportion of the acidic-neutral synergistic extractant in the organic phase is 25-50%.
7. A method for removing silicon from an acidic manganese sulfate solution according to claim 6, characterized in that: The organic phase contains a diluent; the diluent includes light white oil.
8. A method for removing silicon from an acidic manganese sulfate solution according to claim 1, 2, 4 or 7, characterized in that: The extraction conditions are as follows: the extraction level is 1 to 5, and the O / A ratio is 1:1 to 3:
1.
9. The method for removing silicon from an acidic manganese sulfate solution according to claim 1, characterized in that: The silicon-loaded organic phase obtained by the extraction and separation is back-extracted with an aqueous ammonia solution, and the regenerated organic phase is returned to the extraction section.
10. A method for removing silicon from an acidic manganese sulfate solution according to claim 9, characterized in that: The pH of the ammonia solution is 12-14; the stripping conditions are: the number of stages is 1-5, and the ratio of O / A is 1:10-1:20.