阅读说明：本技术 一种制备硫酸锰的离心萃取系统 (Centrifugal extraction system for preparing manganese sulfate ) 是由 张曼曼 张德友 陈崔龙 方毅 邓超 于 2021-08-11 设计创作，主要内容包括：本发明公开一种制备硫酸锰的离心萃取系统,该装置由用于萃取剂预处理的萃取剂皂化单元、实现硫酸锰与钙、镁深度分离的萃取-洗涤-反萃单元、用于萃取剂再生的萃取剂酸洗单元及用于萃余液深度处理的萃余液提锰-除油单元组成。本发明设备布置安装灵活,各工艺料能在萃取机内快速建立相平衡,极大缩短试验时间；而且萃取机内容积小,萃取剂和物料耗用少,节省投资费用；萃取剂可循环使用,原料成本低。通过本发明装置能够实现对硫酸锰的深度提纯,获得满足电池级的高纯硫酸锰产品。(The invention discloses a centrifugal extraction system for preparing manganese sulfate, which consists of an extractant saponification unit for pretreating an extractant, an extraction-washing-back extraction unit for realizing deep separation of manganese sulfate from calcium and magnesium, an extractant pickling unit for regenerating the extractant and a raffinate manganese-extracting-deoiling unit for deeply treating raffinate. The equipment is flexible to arrange and install, and the process materials can quickly establish phase balance in the extraction machine, so that the test time is greatly shortened; the volume in the extractor is small, the consumption of an extracting agent and materials is low, and the investment cost is saved; the extractant can be recycled, and the cost of raw materials is low. The device can realize the deep purification of manganese sulfate and obtain a high-purity manganese sulfate product meeting the battery grade.)

1. The centrifugal extraction system for preparing manganese sulfate is characterized by comprising an extractant saponification unit (1) and an extraction-washing-back extraction unit (2), wherein the extractant saponification unit (1) separates an extractant and a saponifying agent after mixed reaction into a saponified extractant and a saponified liquid, and the extraction-washing-back extraction unit (2) comprises an extraction section (201), a washing section (202) and a back extraction section (203) which are sequentially connected; the saponified extractant enters an extraction section (201) through a first pipeline via a first-stage light phase inlet, manganese materials enter from a last-stage heavy phase inlet of the extraction section (201), manganese in the manganese materials is subjected to phase inversion in the extraction section (201) and enters the saponified extractant, the manganese materials are in countercurrent contact with a washing liquid in the washing section (202), impurities such as calcium and magnesium ions are washed away, and then the manganese materials enter a reverse extraction section (203) and enter a water phase through reverse extraction, so that a high-purity manganese sulfate product is prepared.

2. The centrifugal extraction system for preparing manganese sulfate according to claim 1, wherein the extractant saponification unit (1) comprises an extractant storage tank (101) for containing the extractant, a saponifying agent storage tank (102) for containing the saponifying agent, a mixer (103) for mixing and reacting the extractant and the saponifying agent, and a first oil-water separation device (104) for separating mixed liquid in the mixer (103).

3. The centrifugal extraction system for preparing manganese sulfate according to claim 1 or 2, further comprising a raffinate manganese-deoiling unit (3), wherein the raffinate manganese-deoiling unit (3) comprises a second oil-water separation device (301) and a raffinate manganese centrifugal extractor (302); the saponified extractant enters a raffinate manganese extraction centrifugal extractor (302) through a second pipeline via a first-stage light phase inlet; the manganese material is in reverse contact with the saponified extractant in the first pipeline in the extraction section (201) to generate raffinate, the raffinate enters a raffinate manganese extraction centrifugal extractor (302) and is in reverse contact with the saponified extractant in the second pipeline, manganese in the raffinate enters the saponified extractant to generate loaded organic matters and residual products, the loaded organic matters enter the stripping section (203), the stripping agent enters the last-stage heavy phase inlet of the stripping section (203) and is in countercurrent contact with the loaded organic matters to prepare a high-purity manganese sulfate product, and the residual products are treated by the second oil-water separation device (301) to respectively obtain an oil phase and ammonium sulfate.

4. The centrifugal extraction system for preparing manganese sulfate according to claim 3, further comprising an extractant pickling unit (4), wherein the extractant pickling unit (4) comprises a pickling solution storage tank (401), a pickling solution feed pump (402) and a pickling centrifugal extractor (403), the extractant after stripping from the stripping section (203) enters from a first-stage light phase inlet of the pickling centrifugal extractor (403), the pickling solution is introduced into a last-stage heavy phase inlet of the pickling centrifugal extractor (403) through the feed pump (402), the two phases are in countercurrent contact, the obtained idle extractant is recycled, and the pickling solution after pickling automatically flows into the pickling solution storage tank (401).

5. The centrifugal extraction system for preparing manganese sulfate according to claim 1 or 3, wherein the extractant consists of a diluent and at least one of the following: di (2-ethylhexyl) phosphate, i.e. P204, mono 2-ethylhexyl phosphonate, i.e. P507, di (2,4, 4-trimethylpentyl) phosphinic acid, i.e. Cyanex272, and the diluent is sulfonated kerosene.

6. The centrifugal extraction system for preparing manganese sulfate according to claim 2, wherein the saponification rate of the extractant in the extractant saponification unit (1) is 40-80%, and the saponifying agent is ammonia water or NaOH solution.

7. The centrifugal extraction system for preparing manganese sulfate according to claim 1 or 3, wherein an extraction section (201) in the extraction-washing-stripping unit (2) is 3-5 grades, a washing section (202) is 5-8 grades, and a stripping section (203) is 4-6 grades, and the extraction section (201), the washing section (202) and the stripping section (203) are sequentially connected by steel-based fluorine-lined corrugated hoses.

8. The centrifugal extraction system for preparing manganese sulfate according to claim 1 or 3, wherein the extraction phase ratio O/A of the extraction section (201) is (4-12):1, the extraction phase ratio O/A of the washing section (202) is (10-30):1, and the extraction phase ratio O/A of the stripping section (203) is (8-24): 1.

9. The centrifugal extraction system for preparing manganese sulfate according to claim 4, wherein the stripping agent is introduced into the stripping section (203), and the pickling solution is introduced into the pickling solution storage tank (401) and is sulfuric acid solution with different concentrations.

10. The centrifugal extraction system for preparing manganese sulfate according to claim 4, wherein the extraction stage number of the raffinate manganese extracting centrifugal extractor (302) is 3-5 stages, and the extraction stage number of the extractant acid washing centrifugal extractor (403) is 3-5 stages.

Technical Field

The invention belongs to the field of inorganic salt chemical industry, and particularly relates to a centrifugal extraction system for preparing manganese sulfate.

Background

In recent years, after a lithium ion battery positive electrode material is developed from single lithium cobaltate or lithium manganate to a nickel cobalt lithium manganate ternary material with precise coordination and strict impurity concentration control, the purity requirement on manganese sulfate is high, and particularly, the content of harmful impurities such as potassium, sodium, calcium, magnesium and the like is required to be controlled to be less than 5.0 multiplied by 10^-5. The high-purity manganese sulfate is mainly applied to the production of precursors of ternary or binary materials of the positive electrode of the lithium battery and high-purity manganese oxides. Therefore, the preparation of battery grade high-purity manganese sulfate meeting the requirements is the key for producing the anode material of the lithium ion battery.

Potassium, sodium, heavy metals and the like in industrial manganese sulfate can be reduced to a very low level by various methods, while the removal of calcium and magnesium is always a great problem in the production of high-purity manganese sulfate, and particularly the deep removal of impurities is required for battery grade high-purity manganese sulfate. The method for removing calcium and magnesium in manganese sulfate mainly comprises a crystallization method, an electrolysis method, a chemical precipitation method and an extraction method. The crystallization method is to increase MnSO in the solution₄Concentration to inhibit MgSO₄、CaSO₄The dissolving amount in the solution is to remove magnesium and calcium, but for the leaching solution containing a large amount of magnesium and calcium, the impurity removal process needs to be repeated for many times, so that the recovery rate of manganese is reduced, and the production cost is increased. Meanwhile, MnSO₄And MgSO₄Mixed crystals are formed to affect the solubility and thus the magnesium removal effect. The process for removing calcium and magnesium impurities by an electrolytic method has the advantages of multiple working procedures, long flow, low efficiency and high energy consumption, and if the content of the calcium and magnesium impurities in the solution is high, the hydrogen potential is reduced, so that the production efficiency of a target product is influenced. The chemical precipitation method mainly uses fluoride precipitator. The calcium fluoride and magnesium fluoride produced in the precipitation reaction have excessively fine particles and high viscosity, and are easily formed even at high temperatureWhen the colloid uses fluoride as an impurity removing agent, hydrogen fluoride is easy to generate to corrode equipment if the condition is not well controlled, and the consumption of the fluoride is large and the cost is high.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides a centrifugal extraction system for preparing battery-grade high-purity manganese sulfate, which has the advantages of short flow, high efficiency, low energy consumption and the like.

In order to solve the technical problem, the technical scheme is that the centrifugal extraction system for preparing the manganese sulfate comprises an extractant saponification unit and an extraction-washing-back extraction unit, wherein the extractant saponification unit separates an extractant and a saponifying agent after mixed reaction into a saponified extractant and a saponified liquid, and the extraction-washing-back extraction unit comprises an extraction section, a washing section and a back extraction section which are sequentially connected; and the saponified extractant enters an extraction section through a first pipeline by virtue of a first-stage light phase inlet, manganese materials enter from a last-stage heavy phase inlet of the extraction section, manganese in the manganese materials enters the saponified extractant after being subjected to phase inversion in the extraction section, and is in countercurrent contact with a washing solution in the washing section, and after impurities of calcium and magnesium ions are washed away, the manganese materials enter a back extraction section and enter a water phase by virtue of back extraction, so that a high-purity manganese sulfate product is prepared.

As a further improvement of the centrifugal extraction system for preparing manganese sulfate:

preferably, the extractant saponification unit comprises an extractant storage tank for containing the extractant, a saponifying agent storage tank for containing the saponifying agent, a mixer for mixing and reacting the extractant and the saponifying agent, and a first oil-water separation device for separating mixed liquid in the mixer.

Preferably, the system further comprises a raffinate manganese-oil removal unit, wherein the raffinate manganese-oil removal unit comprises a second oil-water separation device and a raffinate manganese centrifugal extractor; the saponified extractant enters a raffinate manganese extraction centrifugal extractor through a second pipeline through a first-stage light phase inlet; the manganese material is in reverse contact with the saponified extractant in the first pipeline in the extraction section to generate raffinate, the raffinate enters a raffinate manganese extraction centrifugal extractor and is in reverse contact with the saponified extractant in the second pipeline, manganese in the raffinate enters the saponified extractant to generate loaded organic and residual products, the loaded organic enters the stripping section, the stripping agent enters the last heavy phase inlet of the stripping section and is in reverse contact with the loaded organic to prepare a high-purity manganese sulfate product, and the residual products are treated by the second oil-water separation device to respectively obtain an oil phase and ammonium sulfate.

Preferably, still include extractant pickling unit, extractant pickling unit includes pickle storage tank, pickle feed pump and pickling centrifugal extractor, follows the back extraction back extractant that the back extraction section came out gets into by pickling centrifugal extractor first order light phase entry, and the pickle passes through the feed pump and lets in pickling centrifugal extractor last order heavy phase entry, and two-phase countercurrent contact, the unloaded extractant circulation that obtains uses, and pickling back pickle flows into pickle storage tank certainly.

Preferably, the extractant consists of a diluent and at least one of the following: di (2-ethylhexyl) phosphate, i.e. P204, mono 2-ethylhexyl phosphonate, i.e. P507, di (2,4, 4-trimethylpentyl) phosphinic acid, i.e. Cyanex272, and the diluent is sulfonated kerosene.

Preferably, the saponification rate of the extracting agent in the extracting agent saponification unit is 40% -80%, and the saponifying agent is ammonia water or NaOH solution.

Preferably, the extraction section, the washing section and the back extraction section in the extraction-washing-back extraction unit are sequentially connected by steel-based fluorine-lined corrugated hoses, wherein the extraction section is 3-5 grades, the washing section is 5-8 grades, and the back extraction section is 4-6 grades.

Preferably, the extraction phase ratio O/A of the extraction section is (4-12):1, the extraction phase ratio O/A of the washing section is (10-30):1, and the extraction phase ratio O/A of the back-extraction section is (8-24): 1.

Preferably, the stripping agent introduced into the stripping section and the pickling solution in the pickling solution storage tank are sulfuric acid solutions with different concentrations.

Preferably, the extraction stage number of the raffinate manganese extraction centrifugal extractor is 3-5, and the extraction stage number of the extractant acid washing centrifugal extractor is 3-5.

Compared with the prior art, the invention has the beneficial effects that:

1) the invention introduces a centrifugal extractor, and according to the specific process section, the centrifugal extractors with different numbers form an extraction-washing-back extraction unit, a raffinate manganese extraction-oil removal unit and an extractant acid washing unit with different levels. The centrifugal extractor has a compact structure, the equipment arrangement and installation are flexible, the materials of each process can quickly establish phase balance in the extractor, and the test time is greatly shortened; and the volume in the machine is small, the consumption of an extracting agent and materials is reduced, and the investment cost is saved.

2) The invention further extracts manganese from the extracted raffinate, and more manganese in the manganese material can be converted into a high-purity manganese sulfate product, so that the manganese in the manganese material is fully utilized.

3) The device synchronously realizes the acid washing regeneration and the recycling of the extracting agent, and reduces the input cost of raw materials.

4) By the device, the deep purification of manganese can be realized, and a high-purity manganese sulfate product meeting the battery grade is obtained.

Drawings

FIG. 1 is a schematic flow diagram of a centrifugal extraction system for preparing manganese sulfate

The notations in the figures have the following meanings:

1. an extractant saponification unit; 101. an extractant storage tank; 102. a saponifier storage tank; 103. a mixer; 104. a first oil-water separation device;

2. an extraction-washing-stripping unit; 201. an extraction section; 202. a washing section; 203. a back extraction section;

3. raffinate manganese extraction-oil removal unit; 301. a second oil-water separation device; 302. a raffinate manganese extraction centrifugal extractor;

4. an extractant acid washing unit; 401. a pickle liquor storage tank; 402. a pickling solution feeding pump; 403. the extractant acid washes the centrifugal extractor.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to embodiments, and all other embodiments obtained by a person of ordinary skill in the art without any creative effort based on the embodiments of the present invention belong to the protection scope of the present invention.

Example 1

As shown in FIG. 1, the main functions of the extractant saponification unit 1 are pretreatment and storage of the extractant, and the extractant saponification unit comprises an extractant storage tank 101, a saponifying agent storage tank 102, a mixer 103 and a first oil-water separation device 104. The extractant in the extractant storage tank 101 and the saponifier in the saponifier storage tank 102 are respectively conveyed to the mixer 103 for saponification, and the solution after the saponification is introduced into the first oil-water separation device 104 to be separated into the saponified extractant (oil phase) and the saponified liquid (water phase).

The extraction-washing-back extraction unit 2 mainly functions to realize the deep separation of manganese and impurities of calcium and magnesium ions and material phase inversion backflow, and comprises an extraction section 201, a washing section 202 and a back extraction section 203. The saponified extractant enters a first-stage light phase inlet of the extraction section 201 through a first pipeline, and passes through the washing section 202 and the back-extraction section 203 in sequence to obtain a back-extracted extractant, and the back-extracted extractant enters the extractant pickling unit 4 and is regenerated to obtain a recyclable idle-load extractant; manganese material enters from the last-stage heavy phase inlet of the extraction section 201 and is in countercurrent contact with the saponified extractant in the first pipeline, the manganese inversion phase enters the saponified extractant, calcium and magnesium ions are washed away by the washing section 202, and then the manganese material enters the back extraction section 203 and enters the water phase after back extraction, so that a high-purity manganese sulfate product is prepared.

The raffinate manganese extracting and oil removing unit 3 mainly functions to further extract manganese in the raffinate, so as to reduce manganese loss, and comprises a second oil-water separation device 301 and a raffinate manganese centrifugal extractor 302. Manganese material enters from the last-stage heavy phase inlet of the extraction section 201 and is in countercurrent contact with the saponified extractant in the first pipeline to obtain raffinate, the raffinate exits from the first-stage heavy phase outlet of the extraction section 201 and then enters from the last-stage heavy phase inlet of the raffinate manganese-extracting centrifugal extractor 302, the saponified extractant in the second pipeline enters from the first-stage light phase inlet of the raffinate manganese-extracting centrifugal extractor 302, and the two phases are in countercurrent contact to obtain loaded organic and residual products; the loaded organic phase enters a stripping section 203, a stripping agent enters from a heavy phase inlet at the last stage of the stripping section 203 and is in countercurrent contact with the loaded organic phase, and manganese in the loaded organic phase is stripped and enters a water phase to obtain a high-purity manganese sulfate product; and after the residual product enters the second oil-water separation device 301 for treatment, collecting and recycling the obtained oil phase.

The main function of the extractant acid washing unit 4 is to realize extractant regeneration. Comprises a pickling solution storage tank 401, a pickling solution feeding pump 402 and a centrifugal extractor 403 for pickling. The back-extraction extractant prepared from the back-extraction section 203 enters from a first-stage light phase inlet of an extractant pickling centrifugal extractor 403, the pickling solution is introduced into a last-stage heavy phase inlet of the pickling centrifugal extractor 403 through a pickling solution feeding pump 402, the two phases are in countercurrent contact, the obtained no-load extractant is recycled, and the pickling solution after pickling automatically flows into a pickling solution storage tank 401.

The invention will be further illustrated with reference to the following specific examples. These examples are intended to illustrate the invention only and do not limit the scope of the invention.

Example 2

Connecting pipelines according to a device flow chart, wherein the extraction section 201 is 4 stages, the washing section 202 is 8 stages, the back extraction section 203 is 6 stages, the raffinate manganese extraction centrifugal extractor 302 is 3 stages, and the extractant acid washing centrifugal extractor 403 is 3 stages;

the extractant consists of Cyanex272 and diluent sulfonated kerosene, and the organic phase is saponified by adopting concentrated ammonia water as a saponifying agent; the feed liquid contains Mn²⁺、Mg²⁺、Ca²⁺The concentration is 33.54g/L, 1.26g/L and 0.29g/L in sequence; the O/A ratio of the extraction phase ratio (i.e., the volume ratio of the organic phase to the aqueous phase) of the extraction section 201 is 4:1, the O/A ratio of the washing section 202 is 10:1, and the O/A ratio of the stripping section 203 is 8: 1.

After being treated by a centrifugal extraction device, Mn in the obtained manganese sulfate solution²⁺The concentration reaches 65.36g/L, Mg²⁺、Ca²⁺Respectively reduced to 3.12mg/L and 1.18mg/L, thereby reaching the indexes of battery grade high-purity manganese sulfate.

Example 3

The device flow and the extracting agent are the same as those in the embodiment 2, and the concentration of the feed liquid, the O/A ratio of the extraction section 201 and the O/A ratio of the back extraction section 203 are changed;

the feed liquid contains Mn²⁺、Mg²⁺、Ca²⁺Concentration in turn50.31g/L, 0.84g/L and 0.17 g/L; the O/A ratio of the extraction section 201 is 6:1, the O/A ratio of the washing section 202 is 10:1, and the O/A ratio of the stripping section 203 is 10: 1.

After being treated by a centrifugal extraction device, Mn in the obtained manganese sulfate solution²⁺The concentration is 81.70g/L, Mg²⁺、Ca²⁺Respectively 2.08mg/L and 0.69mg/L, and reaches the indexes of battery grade high-purity manganese sulfate.

From the extraction results of the embodiments 2-3, it can be known that by adopting the centrifugal extraction system of the present invention, when the concentration of the feed liquid is changed, the extraction O/a ratio is properly adjusted, and the battery grade high-purity manganese sulfate product meeting the requirements can also be obtained;

example 4

The technological process and the feed liquid adopt the parameters in the example 3, and only the raffinate manganese extraction centrifugal extractor 302 is removed.

After being treated by a centrifugal extraction device, Mn in the obtained manganese sulfate solution²⁺The concentration is 78.43g/L, Mg²⁺、Ca²⁺1.87mg/L and 0.64mg/L respectively, and meets the indexes of battery grade high-purity manganese sulfate.

As can be seen from the extraction results of examples 3-4, the absence of a raffinate Mn-extracting stage affects the Mn in the high-purity manganese sulfate product²⁺The manganese in the feed liquid can not be fully utilized due to the concentration. The technical scheme of the invention can effectively improve the purity of manganese sulfate and prepare high-purity manganese sulfate meeting the requirement of battery grade.

It should be understood by those skilled in the art that the foregoing is only illustrative of several embodiments of the invention, and not of all embodiments. It should be noted that many variations and modifications are possible to those skilled in the art, and all variations and modifications that do not depart from the gist of the invention are intended to be within the scope of the invention as defined in the appended claims.