阅读说明：本技术 一种分离锂溶液中钾离子的系统及分离方法 (System and method for separating potassium ions in lithium solution ) 是由 袁永生 周小强 苏娟 张嫚 于 2021-08-17 设计创作，主要内容包括：本发明涉及一种分离锂溶液中钾离子的系统及分离方法。所述分离锂溶液中钾离子的系统,包括锂溶液储存装置、分离装置、淋洗装置、锂溶液收集装置、淋洗液收集装置和浓缩冷冻装置；其中：所述分离装置分别与所述锂溶液储存装置、所述淋洗装置、所述锂溶液收集装置、所述淋洗液收集装置相连接；所述淋洗液收集装置与所述浓缩冷冻装置相连接。所述分离锂溶液中钾离子的系统,能够有效吸附锂溶液中的钾离子,将钾离子的含量直接降至5g/L以下,使分离钾离子后的锂溶液能够直接用于制备合格的氢氧化锂产品。(The invention relates to a system and a method for separating potassium ions in a lithium solution. The system for separating potassium ions in the lithium solution comprises a lithium solution storage device, a separation device, a leaching device, a lithium solution collection device, a leaching solution collection device and a concentration and refrigeration device; wherein: the separation device is respectively connected with the lithium solution storage device, the leaching device, the lithium solution collecting device and the leaching solution collecting device; the leacheate collecting device is connected with the concentration refrigerating device. The system for separating potassium ions in the lithium solution can effectively adsorb potassium ions in the lithium solution, directly reduce the content of potassium ions to be below 5g/L, and enable the lithium solution after potassium ion separation to be directly used for preparing qualified lithium hydroxide products.)

1. A system for separating potassium ions in a lithium solution is characterized by comprising a lithium solution storage device, a separation device, a leaching device, a lithium solution collection device, a leaching solution collection device and a concentration and refrigeration device; wherein:

the separation device is respectively connected with the lithium solution storage device, the leaching device, the lithium solution collecting device and the leaching solution collecting device;

the leacheate collecting device is connected with the concentration refrigerating device.

2. The system for separating potassium ions from a lithium solution according to claim 1, wherein the washing means comprises a pure water washing means and an inorganic salt solution washing means.

3. The system for separating potassium ions from a lithium solution according to claim 2, wherein the inorganic salt solution leaching device contains an inorganic salt leaching solution, and the inorganic salt leaching solution is a sodium sulfate solution.

4. The system for separating potassium ions in a lithium solution according to claim 1, wherein the separation device is an adsorption column filled with a potassium selective cation exchange resin.

5. A method for separating potassium ions in a lithium solution is characterized by comprising the following steps:

(1) introducing a lithium solution to be treated into the lithium solution storage device, pumping the lithium solution to the separation device, adsorbing potassium ions in the lithium solution by the separation device, and finally flowing the lithium solution to the lithium solution collection device;

(2) introducing an eluent into the leaching device, flushing the separation device adsorbing potassium ions, and finally flowing to the eluent collection device;

(3) and pumping the leaching solution containing potassium ions into the concentration and freezing device for concentration and freezing crystallization, and separating out the potassium element.

6. The method for separating potassium ions from a lithium solution according to claim 5, wherein in the step (1), the molar ratio of the lithium ions to the potassium ions in the lithium solution to be treated is 1-10: 1.

7. The method for separating potassium ions from a lithium solution according to claim 5, wherein in the step (1), the flow rate of the lithium solution to be treated pumped to the separation device is 0.2-10 BV/h.

8. The method for separating potassium ions from a lithium solution according to claim 5, wherein in the step (2), the flow rate of the eluent for washing the separation device is 0.5-3 BV/h.

Technical Field

The invention belongs to the field of separation, and particularly relates to a system and a method for separating potassium ions in a lithium solution.

Background

In the mother liquor produced in the process of producing lithium hydroxide, the content proportion of potassium ions is higher. If the lithium solution mother liquor is directly concentrated and recrystallized, the LiOH & H obtained by crystallization₂In O products, the content of potassium ions is far beyond the standard. Therefore, the mother liquor can not be directly used for preparing the lithium hydroxide monohydrate product at present.

Therefore, the scheme of the invention is provided on the basis of the method.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a system and a method for separating potassium ions in a lithium solution. The system for separating potassium ions in the lithium solution can effectively adsorb potassium ions in the lithium solution, directly reduce the content of potassium ions to be below 5g/L, and enable the lithium solution after potassium ion separation to be directly used for preparing qualified lithium hydroxide products.

The scheme of the invention is that a system for separating potassium ions in a lithium solution is provided, which comprises a lithium solution storage device, a separation device, a leaching device, a lithium solution collection device, a leaching solution collection device and a concentration and refrigeration device; wherein:

the separation device is respectively connected with the lithium solution storage device, the leaching device, the lithium solution collecting device and the leaching solution collecting device;

the leacheate collecting device is connected with the concentration refrigerating device.

Preferably, the washing device comprises a pure water washing device and an inorganic salt solution washing device.

Preferably, the inorganic salt solution leaching device contains an inorganic salt leaching solution, and the inorganic salt leaching solution is a sodium sulfate solution.

Preferably, the separation device is an adsorption column filled with potassium selective cation exchange resin.

Based on the same technical concept, another aspect of the present invention is to provide a method for separating potassium ions from a lithium solution, comprising the following steps:

(1) introducing a lithium solution to be treated into the lithium solution storage device, pumping the lithium solution to the separation device, adsorbing potassium ions in the lithium solution by the separation device, and finally flowing the lithium solution to the lithium solution collection device;

(2) introducing an eluent into the leaching device, flushing the separation device adsorbing potassium ions, and finally flowing to the eluent collection device;

(3) and pumping the leaching solution containing potassium ions into the concentration and freezing device for concentration and freezing crystallization, and separating out the potassium element.

Preferably, in the step (1), the molar ratio of lithium ions to potassium ions in the lithium solution to be treated is 1-10: 1.

Preferably, in the step (1), the flow rate of the lithium solution to be treated pumped to the separation device is 0.2-10 BV/h.

Preferably, in the step (2), the flow rate of the eluent for washing the separation device is 0.5-3 BV/h.

The invention has the beneficial effects that:

the system for separating potassium ions in the lithium solution is internally provided with potassium selective cation exchange resin, and by utilizing the principle that the adsorption selectivity of the resin to potassium ions is far greater than that of lithium ions, the potassium ions in the lithium solution can be effectively adsorbed, the potassium is removed, the content of the potassium ions is directly reduced to be below 5g/L, and the lithium solution after the potassium ions are separated can be directly used for preparing qualified lithium hydroxide products.

Preferably, the cation exchange resin can be repeatedly used after being washed by pure water, so that the use cost is reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a system for separating potassium ions from a lithium solution according to the present invention.

Fig. 2 is a schematic structural diagram of another system for separating potassium ions from a lithium solution according to the present invention.

The reference numbers in the figures are:

1-a lithium solution storage device; 2-a separation device; 3-leaching the device; 31-a pure water leaching device; 32-inorganic salt solution leaching device; 4-a lithium solution collection device; 5-an eluent collecting device; 6-concentration and freezing device.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without any inventive step, are within the scope of the present invention.

Example 1

The embodiment provides a system for separating potassium ions in a lithium solution, and with reference to fig. 1, the system includes a lithium solution storage device 1, a separation device 2, a leaching device 3, a lithium solution collection device 4, a leaching solution collection device 5, and a concentration freezing device 6; wherein:

the separation device 2 is respectively connected with the lithium solution storage device 1, the leaching device 3, the lithium solution collection device 4 and the leaching solution collection device 5;

the leacheate collecting device 5 is connected with a concentration refrigerating device 6.

As an alternative embodiment, referring to fig. 2, the washing apparatus 3 includes a pure water washing apparatus 31 and an inorganic salt solution washing apparatus 32.

As an alternative embodiment, the inorganic salt solution leaching device contains an inorganic salt leaching solution, and the inorganic salt leaching solution is preferably a sodium sulfate solution.

In an alternative embodiment, the separation device is an adsorption column packed with a potassium ion selective cation exchange resin.

Example 2

The embodiment provides a method for separating potassium ions from a lithium solution, which comprises the following steps:

(1) introducing a lithium solution to be treated containing potassium ions into a lithium solution storage device 1, pumping the lithium solution to a separation device 2 at a flow rate of 0.2BV/h, adsorbing the potassium ions to the separation device 2, and finally flowing the residual solution to a lithium solution collection device 4 after the residual solution passes through the separation device 2;

(2) introducing a sodium sulfate solution with the concentration of 10 wt.% into the leaching device 3, flushing the separation device 2 which adsorbs potassium ions at the flow rate of 0.5BV/h to obtain a sodium sulfate solution containing potassium ions, and finally flowing to the leaching solution collecting device 5;

(3) pumping the leaching solution containing potassium ions into a concentration and freezing device 6 for concentration and freezing crystallization to separate out the glaserite, wherein the potassium element is separated out.

The lithium solution after absorbing potassium ions can be directly used for preparing LiOH & H due to the great reduction of the concentration of the potassium ions₂O。

Example 3

The embodiment provides a method for separating potassium ions from a lithium solution, which comprises the following steps:

(1) introducing a lithium solution to be treated containing potassium ions into a lithium solution storage device 1, pumping the lithium solution to an adsorption column filled with cation exchange resin at a flow rate of 5BV/h for adsorption separation, adsorbing the potassium ions in the adsorption column, and allowing the residual solution to flow to a lithium solution collecting device 4 after passing through the exchange column;

(2) introducing pure water to the pure water leaching device 31; introducing a sodium sulfate solution having a concentration of 5 wt.% to the inorganic salt solution leaching unit 32; after the adsorption of the adsorption column is saturated, firstly washing the adsorption column by pure water in a pure water leaching device 31 at the flow rate of 3BV/h, then washing a separation device 2 adsorbing potassium ions by a lithium sulfate solution in an inorganic salt solution leaching device 32 at the flow rate of 3BV/h to obtain a sodium sulfate solution containing potassium ions, enabling the salt solution to flow to a leaching solution collection device 5, continuing to wash the adsorption column by pure water in the pure water leaching device 31, and completing regeneration of resin in the adsorption column for reuse;

(3) and pumping the leaching solution containing potassium ions into a concentration and freezing device 6 for concentration and freezing crystallization, so that potassium element is separated out.

The lithium solution after absorbing potassium ions can be directly used for preparing LiOH & H due to the great reduction of the concentration of the potassium ions₂O。

Example 4

The embodiment provides a method for separating potassium ions from a lithium solution, which comprises the following steps:

(1) introducing a lithium solution to be treated containing potassium ions into a lithium solution storage device 1, pumping the lithium solution to an adsorption column filled with potassium selective cation exchange resin at a flow rate of 5BV/h for adsorption separation, adsorbing the potassium ions in the adsorption column, and allowing the residual solution to flow to a lithium solution collecting device 4 after passing through the exchange column;

(2) introducing pure water to the pure water leaching device 31; introducing a sodium sulfate solution having a concentration of 15 wt.% to the inorganic salt solution leaching unit 32; after the adsorption of the adsorption column is saturated, firstly washing the adsorption column by pure water in a pure water leaching device 31 at the flow rate of 3BV/h, then washing a separation device 2 adsorbing potassium ions by a sodium sulfate solution in an inorganic salt solution leaching device 32 at the flow rate of 3BV/h to obtain a sodium sulfate solution containing potassium ions, enabling the salt solution to flow to a leaching solution collection device 5, continuing to wash the adsorption column by pure water in the pure water leaching device 31, and completing regeneration of resin in the adsorption column for reuse;

(3) and pumping the leaching solution containing potassium ions into a concentration and freezing device 6 for concentration and freezing crystallization, so that potassium element is separated out.

The lithium solution after absorbing potassium ions can be directly used for preparing LiOH & H due to the great reduction of the concentration of the potassium ions₂O。

In order to show the effect of separating potassium ions, the content of potassium ions in the lithium solution before and after separation in examples 2 to 4 was measured, and the results are shown in table 1.

TABLE 1

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.