WO2016064163A2 - Metal separation method using precipitation reaction in couette-taylor reactor and metal separation apparatus therefor - Google Patents

Abstract

The present invention relates to a metal separation method and a metal separation apparatus therefor. The metal separation method according to the present invention is directed to a method for separating metals from a metal solution containing a first metal and a second metal, wherein the method comprises the steps of: carrying out a reaction of the metal solution using a Couette-Taylor reactor in the conditions in which metal hydroxide precipitation tendencies of the first and second metals are different; and solid-liquid separating an effluence from the Couette-Taylor reactor.

Description

Metal Separation Method Using Precipitation in Cuette-Taylor Reactor and Separator

The present invention relates to a metal separation method and a separation device therefor.

There are many processes in the industrial field to separate the metal mixed in the solution. In particular, there are many processes in which ferrous and nonferrous metals must be separated from a metal solution in which ferrous and nonferrous metals are mixed. For example, in the smelting process of nonferrous metals, separation of iron and nonferrous metals is required.

In the case of ferrous and non-ferrous metals, conventional separation methods include the gothite precipitation method and the iron hydroxide precipitation method. The gothite precipitation method oxidizes iron and precipitates iron in the form of gothite, which has a disadvantage that the reaction temperature is about 80 ° C. and the separation is not high. Iron hydroxide precipitation is performed at room temperature and has a high degree of separation, but the filterability of the precipitate is poor, which makes it difficult to filter.

Accordingly, it is an object of the present invention to provide a method for separating a metal having a high degree of separation and a separation process, and a separation device for the same.

An object of the present invention is a method for separating iron and nonferrous metals from a metal solution containing iron and non-ferrous metal, comprising the steps of oxidizing at least a portion of iron in the metal solution from divalent to trivalent; Reacting the metal solution oxidized with iron in a Kuet-Taylor reactor; Solid-separating the effluent from the Quet-Taylor reactor.

The pH in the reaction step may be 3 to 5.

The oxidation step can take place in a Quet-Taylor reactor.

The reaction is a continuous process and the pH control agent and the oxidant may be continuously added to the Kuet-Taylor reactor.

The non-ferrous metal may be less prone to precipitation of metal hydroxide than iron of trivalent ions in the pH conditions of the reaction step.

The non-ferrous metal may have a pH at which hydroxide is generated is three or more higher than iron of trivalent ions.

The nonferrous metal may include at least one of aluminum, nickel, cobalt, zinc, and copper.

The solid-liquid separation may be performed through a filtering method.

The reaction step may be performed at room temperature.

The object of the present invention is a method for separating iron and non-ferrous metals from a metal solution containing iron and non-ferrous metals, the step of reacting the metal solution in a Kuet-Taylor reactor to precipitate the iron into crystalline FeOOH; Solid-separating the effluent from the Kuet-Taylor reactor.

The precipitation step may be performed under conditions in which the tendency of the metal hydroxide precipitation of iron is greater than the tendency of the metal hydroxide precipitation of the nonferrous metal.

The pH of the precipitation step may be 3 to 5.

The precipitation step may be performed at room temperature.

The method may further include oxidizing the iron from divalent to trivalent.

The precipitation step is a continuous process and the pH control agent and the oxidant may be continuously added to the Kuet-Taylor reactor.

The non-ferrous metal may have a pH at which hydroxide is generated is three or more higher than iron of trivalent ions.

The nonferrous metal may include at least one of aluminum, nickel, cobalt, zinc, and copper.

The solid-liquid separation may be performed through a filtering method.

The object of the present invention is a method for separating a metal from a metal solution containing a first metal and a second metal, the Cue-Taylor reactor under conditions in which the metal hydroxide precipitation tendency of the first metal and the second metal is different Reacting the metal solution using; Solid-separating the effluent of the Kuet-Taylor reactor.

Conditions for which the precipitation tends to be different may include pH conditions.

The method may further include changing an ionic state to change a metal hydroxide precipitation tendency according to pH with respect to at least one of the first metal and the second metal.

By changing the ion state, the pH of the hydroxide formation of the first metal and the second metal may vary by 3 or more.

The reaction is carried out at room temperature, the solid-liquid separation may be carried out by a filtering method.

Another object of the present invention and the Kuet-Taylor reactor body including a reaction space therein; A pH regulator supply unit for supplying a pH regulator to the reaction space; An oxidant supply unit supplying an oxidant to the reaction space; A reaction solution supply unit supplying a reaction solution containing iron and nonferrous metals to the reaction space; It can be achieved by a separation device of iron and non-ferrous metal including a filtering portion for solid-liquid separation of the effluent flowing out of the reaction space.

PH measuring unit for measuring the pH of the reaction space; A control unit for controlling the supply amount of the pH adjuster supply unit based on the measurement result of the pH measuring unit may be further included.

According to the present invention, there is provided a method for separating a metal having a simple process and a high degree of separation, and a separator for the same.

1 shows a separation device according to an embodiment of the present invention,

Figure 2 shows the reaction control in the separation device according to an embodiment of the present invention,

Figure 3 shows the hydroxide precipitation tendency of the metal to be separated,

Figure 4 shows a separation method according to an embodiment of the present invention,

Figure 5 shows a separation method according to another embodiment of the present invention,

Figure 6 shows the precipitation rate of iron and cobalt in the first experimental example of the present invention,

Figure 7 shows the precipitation rate of iron and cobalt in the second experimental example of the present invention,

8 is an XRD graph of iron precipitate obtained in Experimental Example 2 of the present invention.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

The accompanying drawings are only examples as illustrated in order to explain the technical idea of the present invention in more detail, and thus the spirit of the present invention is not limited to the accompanying drawings.

 In the following description, the separation of iron and nonferrous metals will mainly be described. However, the present invention is not limited thereto, and may be applied to separating two or more metals.

1 is a separator of ferrous and nonferrous metals according to the present invention.

The separator consists of a reactor 10, a filtering unit 20, a reactant supply unit 30, a pH measuring unit 41 and a control unit 50.

The reactor 10 of the present invention is a Kuet-Taylor reactor. In the Kuet-Taylor reactor, the reaction space S is formed between the inner cylinder 11 and the outer cylinder 12. As the inner cylinder 11 rotates at a high speed, a vortex (taylor vortex) is formed in the reaction space S. The reaction is promoted by the vortex formed while flowing from the left side to the right side of the reaction space (S).

Rotating means 13 and a rotating shaft 14 for rotating the inner cylinder 11 are provided, and sealing parts 15 and 16 are provided on the left and right of the reaction space S.

In the outer cylinder 11, a plurality of communication holes 17a to 17e are formed. The reaction solution is supplied to the reaction space S from the outside through some communication holes 17a, 17c, and 17d, and the reaction state of the reaction space S is checked through the other communication holes 17b. . The reactant after the reaction flows out through the communication hole 17e.

The filtering unit 20 solid-separates the effluent from the reactor 10. In the exemplary embodiment, the filtering is performed by using a natural load, but in another exemplary embodiment, the filtering may be performed by using pressure and / or vacuum.

The reactant supply unit 30 includes pH adjuster supply units 31a and 31b, oxidant supply units 32a and 32b, and reaction solution supply units 33a and 33b. The pH regulator supply parts 31a and 31b include a pH regulator tank 31a and a pump 31b, and the oxidant supply parts 32a and 32b include an oxidant tank 32a and a pump 32b, and a reaction solution supply part ( 33a, 33b includes a reaction solution tank 33a and a pump 33b.

The pH regulator, the oxidizing agent and the reaction solution are continuously supplied through the reactant supply unit 30, and the reactants are continuously discharged through the communication hole 17e, so that the entire reaction may be made in a continuous reaction.

The pH measuring unit 41 measures the pH of the reaction space (S) through the communication hole (17b).

Figure 2 shows a control unit of the separation device according to the present invention.

The controller 50 receives the pH of the reaction space S from the pH measuring unit 41 and controls the flow rate of the pH regulator pump 31b to obtain a desired pH. In addition, the controller 50 controls the oxidant pump 32b and the reaction solution pump 33b so that a constant reaction is performed.

In another embodiment, the reactor 10 further includes a temperature measuring part and a temperature adjusting part of the reaction space S, and the controller 50 may control the temperature adjusting part based on the measured temperature. The temperature control part may be made of a jacket type surrounding the outer cylinder 12 or may be provided to adjust the temperature of the reaction solution tank 33a.

Hereinafter, a separation method according to the present invention will be described.

The present invention utilizes the fact that metal hydroxide precipitation tends to vary depending on pH and metal ion state, and that a hydroxide of a crystalline form can be obtained by the Kuet-Taylor reaction.

 Figure 3 shows the metal hydroxide precipitation tendency by metal at 25 ℃ (E. Jackson, Hydrometallugical Extraction and Reclamation, Ellis Horwood publishing, etc. can be found). The iron (Fe) shows a high hydroxide precipitation tendency when the pH is higher than 7 to 8 in the divalent state, but a high precipitation tendency when the pH is higher than about 2 in the trivalent state. In addition, when the pH is higher than 7 to 8, nickel, It can be seen that cobalt, silver, manganese, zinc and the like have a high hydroxide precipitation tendency.

Therefore, converting iron to trivalent and maintaining a pH between 2 and 7 can make a difference in the hydroxide precipitation tendency of iron and other nonferrous metals. In other words, in this pH condition, iron is more selectively precipitated as a hydroxide than other nonferrous metals, and thus iron and nonferrous metals can be separated.

As such, when the hydroxide reaction is carried out at pH conditions in which the precipitation tendency of both metals is different, one metal precipitates as a hydroxide and the other metal remains in solution, allowing separation.

In the Kuet-Taylor reactor, the reaction occurs in the Taylor turbulence, leading to the resulting solid phase in crystalline form. Fe ^{3 +} in the solution are precipitated as a tight bars (FeOOH) form, bars are tight This crystal form. The precipitation of iron in the form of gothite herein means that most of the precipitated iron, for example at least 80%, or at least 90% or at least 95% or at least 99%, is precipitated in crystalline goatite form.

Crystalline gothite is easier to filter than iron hydroxide. Thus, filtering by self weight can also be performed in a fairly short time.

In addition, using the Kuet-Taylor reactor, crystalline goatite can be obtained at room temperature. Reaction at room temperature can simplify the reactor structure and reduce operating costs.

A separation method according to the present invention will be described with reference to FIG. 4.

First, the reaction solution is injected into the reactor (S101). The reaction solution contains two or more metals, and may be iron and nonferrous metals. The reaction solution is not limited thereto, but may be obtained in a non-ferrous metal manufacturing process or a waste battery recycling process.

It is important to completely separate a small amount of iron from the non-ferrous metal in the non-ferrous metal manufacturing process, it can be removed using the present invention.

In the waste battery recycling, a reaction solution containing the cathode active material of the waste battery can be obtained. In this case, the reaction solution may include at least one of iron, manganese, nickel, cobalt, and lithium.

In waste battery recycling, (1) separating the waste battery pack into waste battery modules (2) separating the waste battery module to obtain waste battery cells (3) obtaining positive and negative active materials from the battery cells (4) positive and negative active materials After discharging and drying, to obtain a positive electrode (5) to crush the positive electrode and to separate the particle size, and then leaching sulfuric acid (6) to remove aluminum and copper through precipitate filtration to obtain a reaction solution.

The reaction solution may be prepared in various ways, such as two components (iron and cobalt, etc.), three components (iron, cobalt, manganese, etc.), and four components (iron, cobalt, manganese, nickel, etc.).

Next, iron is oxidized from divalent to trivalent (S102). This is to change the hydroxide precipitation tendency of iron and nonferrous metals according to pH. Trivalently oxidized iron tends to precipitate hydroxide above pH 2, while most other nonferrous metals tend to precipitate hydroxide above pH above pH 2.

Oxidation of iron may be performed by injecting an oxidant into the reaction space. The oxidant is not limited thereto, and hydrogen peroxide may be used.

Next, trivalent iron is precipitated as a goot (S103). This process can be carried out with constant pH.

PH for the separation of ferrous and nonferrous metals varies from 2 to 7, 2 to 6, 2 to 5, 2 to 4, 2 to 3, 3 to 6, 3 to 5, 3 to 4, 4 to 6 or 4 to 5 Can be adjusted. Specifically, the pH can be adjusted to 3, 4, 5, or 6. The pH may vary depending on the nonferrous metal component.

pH control may be performed by injecting a pH control agent into the reaction space. The pH adjusting agent may vary depending on the pH of the reaction solution and the desired pH. If the reaction solution is a sulfuric acid solution and the pH is lower than 5 and the desired pH is 5, a basic solution such as NaOH may be used as the pH adjusting agent. The dose of pH adjuster can be adjusted while monitoring the pH of the reaction space.

Reaction solution injection (S101), iron oxidation (S102) and FeOOH formation (S103) described above can all be made in a single reaction space of the Kuet-Taylor reactor, in which case these reactions can be substantially simultaneously performed.

On the other hand, the separation reaction using the Kuet-Taylor reactor may be carried out at room temperature, the reaction may be carried out in a continuous reaction.

Next, the effluent flowing out of the reactor is filtered out. Iron precipitates in the gothite crystalline form and is present in the solid phase, while other nonferrous metals are present in solution in an ionic state. Therefore, filtering the effluent can separate ferrous and nonferrous metals.

The present invention is not limited to the separation of iron, but may be applied to the separation of metals in a metal solution, which will be described with reference to FIG. 5.

First, a reaction solution including the first metal and the second metal is prepared (S201), and both the first metal and the second metal may not be iron.

Next, the precipitation conditions of the first metal and the second metal are changed (S202). This is to selectively precipitate only one of the first metal and the second metal by precipitation reaction under different precipitation conditions. The precipitation reaction rate may be, for example, at least 80%, at least 90%, at least 95%, or at least 99% of the first metal and at most 20%, at most 10%, at most 5%, or at most 1%. Alternatively, the precipitation rate of the first metal may be 10 times, 20 times, 30 times, 50 times, or 100 times higher than the precipitation rate of the second metal.

Precipitation conditions may be pH, but is not limited thereto and may be variously selected such as temperature or reactor rpm. If the precipitation conditions of the first metal and the second metal are already different, this step may be omitted.

This may be performed by changing the ionic state of any one of the first metal and the second metal to adjust the pH at which precipitation occurs. Thereby, it can be adjusted so that the difference in pH of both metals in which precipitation is made may be 6, 5, 4, 3, or 2 or more.

Since the precipitation conditions are different from the precipitation reaction (S203) is carried out. At this time, the precipitation reaction is carried out in the intermediate condition of the precipitation conditions of both metals. For example, when the hydroxide generation pH of the first metal is 2 or more, and the hydroxide production pH of the second metal is 7 or more, the precipitation reaction may be performed while maintaining the pH between 2 and 7. Specifically, the precipitation reaction is controlled by adjusting the pH to 2 to 7, 2 to 6, 2 to 5, 2 to 4, 2 to 3, 3 to 6, 3 to 5, 3 to 4, 4 to 6 or 4 to 5 Can be done. More specifically, the precipitation reaction may be carried out while adjusting the pH to 3, 4, 5 or 6.

By precipitation reaction (S203) any one of the first metal and the second metal is selectively precipitated to form a solid phase.

After the solids separation (S204) the effluent is made of metal separation.

The present invention will be described in more detail using the following experimental examples.

In the experiment, a reaction solution containing iron and cobalt was carried out. Cobalt was used for CoSO ₄ 7H ₂ O and FeSO ₄ 7H ₂ O was used for iron. Cobalt and iron were diluted with water and a certain amount of sulfuric acid was added to lower the pH.

As the Kuet-Taylor reactor, LAMINAR and LCR-TERA 3100 were used, and ICP-OES was used for metal analysis. A 2 M NaOH aqueous solution was used as a pH adjusting agent and a 34.5% hydrogen peroxide aqueous solution was used as an oxidizing agent. The reactor RPM was 600 and the reaction was carried out at 25 ° C.

The reactor was first filled with distilled water and the distilled water was substituted while supplying the reaction solution, pH adjuster and oxidant. The distillate was sampled every 30 minutes after all the distilled water had been replaced and the pH was set to 5. The sampled effluent was filtered and analyzed by XRD on the liquid component to obtain the precipitation rate of each component.

Experimental Example 1

The concentration of the metal component was 3 g / L cobalt and 30 g / L iron. The pH of the reaction solution was 3.22, NaOH was added to maintain the pH 5.

Experimental results are shown in Table 1 and FIG. 6 below.

Minutes	ICP- OES ; Co mg / L	ICP- OES Fe mg / L	Co precipitation rate (%)	Fe precipitation rate (%)
30	1490	0.31	3.43	99.9
60	1570	0.25	1.62	99.8
90	1650	1.80	6	99.8
120	1620	1.39	8.9	99.8
150	1470	1.04	4.8	99.9
180	1470	0.25	12.6	99.9

As shown in the results, iron was precipitated more than 99%, while cobalt was precipitated to less than 10%. Therefore, it was confirmed that iron and cobalt can be separated.

On the other hand, the filtering was carried out by its own weight, and it was confirmed that the filtering was performed in a shorter time than the general iron hydroxide.

Experimental Example 2

The concentration of the metal component was 90 g / L cobalt and 9 g / L iron. The pH of the reaction solution was 1.91, and NaOH was added to keep the pH at 5.

Experimental results are shown in Table 2 and FIG. 7 below.

Minutes	ICP- OES ; Co mg / L	ICP- OES  Fe mg / L	Co precipitation rate (%)	Fe precipitation rate (%)
30	44600	0.25	3.8	99.9
60	48900	0.25	5.51	99.9
90	50900	0.25	9.9	99.9
120	52900	0.25	14.1	99.9
150	50800	0.25	9.6	99.9
180	50400	0.25	8.8	99.9

As shown in the results, iron was precipitated more than 99%, while cobalt was precipitated to less than 10%. Therefore, it was confirmed that iron and cobalt can be separated.

On the other hand, the filtering was carried out by its own weight, and it was confirmed that the filtering was performed in a shorter time than the general iron hydroxide.

8 is an XRD analysis of the solid precipitate after the filter. A peak corresponding to crystalline FeOOH was found, confirming that iron precipitated into crystalline FeOOH.

The above-described embodiments are examples for explaining the present invention, but the present invention is not limited thereto. Those skilled in the art to which the present invention pertains will be capable of carrying out the present invention by various modifications therefrom, and the technical protection scope of the present invention should be defined by the appended claims.

The present invention can be used for separation between metals.

Claims (25)

1. In the method for separating ferrous and nonferrous metals from a metal solution containing ferrous and nonferrous metals,

   Oxidizing at least a portion of iron in the metal solution from divalent to trivalent;

   Reacting the metal solution oxidized with iron in a Kuet-Taylor reactor;

   A method for separating ferrous and nonferrous metals comprising solid-liquid separation of an effluent from a Quet-Taylor reactor.
2. In claim 1,

   PH of the reaction step is a separation method of iron and non-ferrous metal, characterized in that 3 to 5.
3. In claim 2,

   The oxidation step is a separation method of iron and non-ferrous metal, characterized in that in the Kuet-Taylor reactor.
4. In claim 3,

   The reaction is a continuous process and the method of separating the ferrous and non-ferrous metal, characterized in that the pH control agent and the oxidant is continuously added to the Kuet-Taylor reactor.
5. In claim 1,

   The non-ferrous metal is a separation method of iron and non-ferrous metals, characterized in that the metal hydroxide precipitation tends to be less than the trivalent iron in the pH conditions of the reaction step.
6. In claim 5,

   The non-ferrous metal is a separation method of iron and non-ferrous metal, characterized in that the pH of the hydroxide is formed more than three than the iron of trivalent ions.
7. In claim 5,

   The non-ferrous metal is an iron, non-ferrous metal separation method characterized in that it comprises at least any one of nickel, cobalt, zinc, copper.
8. In claim 1,

   The solid-liquid separation is a separation method of ferrous and non-ferrous metal, characterized in that carried out through a filtering method.
9. In claim 1,

   The reaction step is separated iron and non-ferrous metal, characterized in that carried out at room temperature.
10. In the method for separating ferrous and nonferrous metals from a metal solution containing ferrous and nonferrous metals,

    Reacting the metal solution in a Kuet-Taylor reactor to precipitate the iron into crystalline FeOOH;

    Solid-liquid separation of the effluent from the Kuet-Taylor reactor.
11. In claim 10,

    The precipitation step is a method of separating iron and nonferrous metals, characterized in that the metal hydroxide precipitation tendency of iron is carried out in a condition larger than the metal hydroxide precipitation tendency of the nonferrous metal.
12. In claim 11,

    PH of the precipitation step is a separation method of iron and non-ferrous metal, characterized in that 3 to 5.
13. In claim 11,

    The precipitation step is a separation method of iron and nonferrous metals, characterized in that carried out at room temperature.
14. In claim 11,

    Separating the iron and non-ferrous metal further comprising the step of oxidizing the iron from divalent to trivalent.
15. The method of claim 14,

    The precipitation step is a continuous process and the method of separating the ferrous and non-ferrous metal, characterized in that the pH control agent and the oxidant is continuously added to the Kuet-Taylor reactor.
16. The method of claim 14,

    The non-ferrous metal is a separation method of iron and non-ferrous metal, characterized in that the pH of the hydroxide is formed more than three than the iron of trivalent ions.
17. In claim 10,

    The non-ferrous metal is an iron, non-ferrous metal separation method characterized in that it comprises at least any one of nickel, cobalt, zinc, copper.
18. In claim 10,

    The solid-liquid separation is a separation method of ferrous and non-ferrous metal, characterized in that carried out through a filtering method.
19. In the method for separating the metal in the metal solution containing the first metal and the second metal,

    Reacting the metal solution using a Kuet-Taylor reactor under conditions in which the metal hydroxide precipitation tendency of the first metal and the second metal is different;

    Solid-liquid separation of the effluent of the Kuet-Taylor reactor.
20. The method of claim 19,

    Conditions for different precipitation tendency include a metal separation method characterized in that it comprises a pH condition.
21. The method of claim 20,

    And changing the ionic state to change the metal hydroxide precipitation tendency according to pH for at least one of the first metal and the second metal.
22. The method of claim 21,

    The hydroxide formation pH of the first metal and the second metal is changed by at least three by the ion state change.
23. The method of claim 19,

    The reaction is carried out at room temperature,

    The solid-liquid separation is metal separation method, characterized in that carried out by a filtering method.
24. A Kuet-Taylor reactor body including a reaction space therein;

    A pH regulator supply unit for supplying a pH regulator to the reaction space;

    An oxidant supply unit supplying an oxidant to the reaction space;

    A reaction solution supply unit supplying a reaction solution containing iron and nonferrous metals to the reaction space;

    Separation device of iron and non-ferrous metal comprising a filtering unit for separating the effluent flowing out of the reaction space in a solid-liquid.
25. The method of claim 24,

    PH measuring unit for measuring the pH of the reaction space;

    Separating device for iron and non-ferrous metal, characterized in that further comprising a control unit for controlling the supply amount of the pH regulator supply unit based on the measurement result of the pH measuring unit.

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