CN220520651U - Metal lithium electrolytic tank - Google Patents

Abstract

The utility model discloses a metal lithium electrolytic tank, belongs to the technical field of electrolytic preparation of metals, and is mainly used for preparing metal lithium by molten salt electrolysis. The utility model aims to solve the technical problem of providing a metal lithium electrolytic tank, which comprises a tank body and a cover body, wherein an anode is arranged in the tank body, the bottom end of the anode is electrically connected with an anode conducting plate, a cathode is circumferentially arranged on the anode and is electrically connected with the inner wall of the tank body, and the outer wall of the tank body is electrically connected with a cathode conducting plate; an annular separation net is further arranged between the anode and the cathode, the separation net is arranged on the circumference of the anode to divide the tank body into an anode region and a cathode region, the upper end of the separation net is connected with the cover body, the lower end of the separation net is in butt joint with the bottom surface of the tank body, a gas absorption pipeline and an anode opening are arranged on the cover body, and a cathode opening is arranged on the upper portion of the cathode. By adopting the lithium metal electrolytic tank for preparing lithium metal, slag materials falling off from the anode are prevented from entering the cathode, the electrolytic efficiency of the cathode is influenced, the discharge tank and the feeding of the continuous tank are realized, and the lithium metal is continuously produced by electrolysis.

Description

Metal lithium electrolytic tank

Technical Field

The utility model relates to the technical field of electrolytic preparation of metals, in particular to a metal lithium electrolytic tank.

Background

The preparation of metallic lithium by electrolysis of chloride molten salt is a common metallic lithium production process, and key control parameters of the process are the configuration of an electrolytic tank and the purity of raw materials. At present, common metal lithium electrolytic tanks are divided into an upper plug-in electrolytic tank and a lower plug-in electrolytic tank according to the anode installation mode, such as the metal lithium electrolytic tank proposed by the publication No. CN207749191U, and after long-time electrolysis, li in the electrolyte ⁺ The content of the metal lithium is reduced, so that the subsequent output of the metal lithium is reduced, and at the moment, the energization is stopped to prepare the metal lithium, and the electrolyte in the electrolytic tank is replaced; in addition, long-time electrolysis can also cause the graphite anode to drop a large amount of slag, the mixing of the slag in the electrolyte can influence the fluidity of the electrolyte, part of slag can be adsorbed on the surface of the cathode, the electrolysis efficiency of the cathode is reduced, the yield of metal lithium is influenced, and when the situation is serious, the electrifying is stopped to prepare the metal lithium, so that the slag attached to the surface of the cathode is treated; it can be seen that the existing electrolytic cell cannot continuously electrolyze to produce high-purity metallic lithium.

Disclosure of Invention

The utility model aims to solve the technical problem of providing a metal lithium electrolytic tank which is mainly used for preparing metal lithium by molten salt electrolysis so as to achieve the purpose of producing high-purity metal lithium by continuous electrolysis.

The utility model discloses a metal lithium electrolytic tank, which comprises a tank body, wherein a cover body is arranged above the tank body, an anode is vertically arranged in the tank body, the bottom end of the anode is electrically connected with an anode conducting plate, a cathode is circumferentially arranged around the anode, the cathode is electrically connected with the inner wall of the tank body, and the outer wall of the tank body is electrically connected with a cathode conducting plate; the method is characterized in that: an annular separation net is arranged between the anode and the cathode, the separation net is circumferentially arranged on the anode and divides the tank body into an anode region and a cathode region, the upper end of the separation net is connected with the cover body, the lower end of the separation net is abutted with the bottom surface of the tank body, a gas absorption pipeline, an anode port and a cathode port are arranged on the cover body, and the gas absorption pipeline is positioned above the anode; the anode port and the cathode port may be closed, the anode port being located above the anode, and the cathode port being located above the cathode.

Further, a siphon device is arranged on the outer side of the anode port.

Further, a guide pipe is further arranged on the groove cover, the guide pipe is located above the cathode region, one end of the guide pipe extends into the groove body, the other end of the guide pipe is connected with the metal lithium collecting chamber, and a lithium pump is further arranged on the guide pipe.

Further, the mesh diameter of the separation net is 10-10000 μm.

Preferably, the separation net is detachably connected with the cover body, and the separation net is made of stainless steel.

As a preferred form, the pores of the screen are provided with ceramic, polymer or fibres.

As a preferred mode, the separation net is a double-layer structure, and ceramics, polymers or fibers are filled in the middle of the double-layer structure.

Furthermore, refractory bricks are arranged above the bottom surface of the tank body, and the anode is arranged in the tank body through the refractory bricks.

The beneficial effects of the utility model are as follows: by arranging the annular separation net between the anode and the cathode, the whole metal lithium electrolytic tank is divided into an anode region and a cathode region, slag materials falling off from the anode cannot enter the cathode region through the separation net, further, the influence of the slag materials on the cathode on the electrolytic efficiency of the cathode is avoided, and meanwhile, the influence on the purity of the metal lithium produced in the cathode region is reduced; meanwhile, the electrolyte in the anode region and the electrolyte in the cathode region are effectively separated by the separation net, the molten electrolyte in the two regions are relatively static under the action of no external force, the molten electrolyte in the two regions can flow through the separation net, when the electrolyte in the anode region cannot continue to electrolyze, the electrolyte in the anode region is taken out from the anode port, and meanwhile, new electrolyte is added into the cathode region from the cathode port, and due to the liquid level difference of the anode region and the cathode region, the new electrolyte added into the cathode region can flow into the anode region to supplement the electrolyte in the anode region, so that the electrolytic process reaches dynamic balance, the discharge and the feeding can be performed without stopping the tank, the adverse influence on the production caused by operations such as stopping the tank and slotting is reduced, and the aim of continuously preparing high-purity metallic lithium is fulfilled.

Drawings

Fig. 1: the structure of the electrolytic tank is schematically shown;

fig. 2: electron microscope pictures of graphite anode fall-off.

Reference numerals: 1-anode, 2-cathode, 3-screen, 4-anode port, 5-cathode port, 6-cathode conductive plate, 7-anode conductive plate, 8-gas absorption pipeline, 9-cover, 10-tank, 101-anode region, 102-cathode region, 11-refractory brick; 12-conduit, 13-metallic lithium collection chamber; 14-a lithium extraction pump; 15-an extraction tube; 16-siphon pump.

Detailed Description

The utility model will be further described with the following, taking care that the quality electrolyte referred to herein refers to: the mass fraction of the main component KCl-LiCl is more than 99.9%, and the electrolyte has very good electrolytic process without infusible impurities such as carbon powder particles and the like; the poor electrolyte refers to: the mass fraction of main component KCl-LiCl is between 99.5% and 99.9%, the mass fraction of infusible impurities such as carbon powder particles is lower than 0.05%, the electrolytic process is abnormal, and the electrolyte is usually used together with high-quality electrolyte; the deteriorating electrolyte means: the mass fraction of the main component KCl-LiCl is less than 99.5%, the mass fraction of infusible impurities such as carbon powder particles is more than 0.05%, and the electrolyte cannot be electrolyzed; in the present utility model, ppm means the mass fraction of solute, parts per million, unless otherwise specified.

The utility model provides a metal lithium electrolytic tank which is mainly used for preparing metal lithium by molten salt electrolysis and comprises a tank body 10, wherein a cover body 9 is arranged above the tank body 10, an anode 1 is vertically arranged in the tank body 10, the bottom end of the anode 1 is electrically connected with an anode conducting plate 7, a cathode 2 is circumferentially arranged around the anode 1, the cathode 2 is electrically connected with the inner wall of the tank body 10, and the outer wall of the tank body 10 is electrically connected with a cathode conducting plate 6; a separation net 3 is further arranged between the anode 1 and the cathode 2, the separation net 3 is circumferentially arranged on the anode 1 and divides the tank body 10 into an anode region 101 and a cathode region 102, the upper end of the separation net 3 is fixedly connected with a cover body 9, the lower end of the separation net 3 is abutted to the bottom surface of the tank body 10, a gas absorption pipeline 8, an anode port 4 and a cathode port 5 are arranged on the cover body 9, and the gas absorption pipeline 8 is positioned above the anode 1; the anode port 4 and the cathode port 5 may be closed, the anode port 4 being located above the anode 1 and the cathode port 5 being located above the cathode 2.

When the lithium metal electrolytic tank is used, KCl-LiCl electrolyte in a molten state is introduced into the electrolytic tank from an anode port 4 or a cathode port 5, so that the electrolyte is enabled to permeate through an anode 1 and a cathode 2, direct current is introduced into the anode 1 and the cathode 2, the electrolyte and the anode 1 undergo oxidation reaction, chlorine gas is separated out, the chlorine gas can be uniformly collected and treated through a gas absorption pipeline 8, the electrolyte and the cathode 2 undergo reduction reaction, metal lithium is separated out, the metal lithium is accumulated above the molten electrolyte due to the density of the metal lithium being less than one third of the density of the molten electrolyte, and when the metal lithium floating above the electrolyte needs to be taken out, the cathode port 5 is opened, and the metal lithium is taken out from the cathode port 5; the cathode 2 is arranged around the anode 1, the distance between two poles is reduced, the current efficiency is effectively improved, an annular separation net 3 is arranged between the anode 1 and the cathode 2, the upper end of the separation net 3 is connected with a cover body 9, the lower end of the separation net 3 is abutted with the bottom surface of a tank body 10, the whole metal lithium electrolytic tank is divided into an anode region 101 and a cathode region 102, slag falling off from the anode 1 cannot enter the cathode region 102 through the separation net 3, further, the influence of slag on the cathode 2 on the electrolysis efficiency of the cathode 2 is avoided, and meanwhile, the influence on the purity of metal lithium produced in the cathode region 102 is also reduced; the annular separation net 3 effectively separates the electrolytes of the anode region 101 and the cathode region 102 when isolating slag materials fallen from the anode 1, the molten electrolytes in the two regions are relatively static under the action of no external force, and the molten electrolytes in the two regions can flow through the separation net 3; when the electrolyte in the anode region 101 cannot continue to electrolyze, the anode opening 4 and the cathode opening 5 are opened, the electrolyte in the anode region 101 is taken out from the anode opening 4, new electrolyte is added into the cathode region 102 from the cathode opening 5 while the electrolyte in the anode region 101 is taken out, and the new electrolyte added into the cathode region 102 can flow into the anode region 101 to supplement the electrolyte in the anode region 101 due to the liquid level difference of the anode region 101 and the cathode region 102, so that the dynamic balance of the electrolysis process is achieved, the discharge and the charging can be carried out without stopping the tank, the adverse effect on the production caused by the operations such as stopping the tank and slotting is reduced, and the aim of continuously preparing the high-purity metallic lithium is fulfilled.

In addition, the device can also effectively reduce the production cost, and as the separation net 3 can well separate electrolytes at two sides of a cathode and an anode, the electrolyte added in the anode region 101 which can not produce metal lithium can be inferior electrolyte, and the high-quality electrolyte is added in the cathode region 102 which can produce metal lithium; because the effect of the anode is mainly to balance charges, the purity of the electrolyte can be not too high, after a period of electrolysis, the poor electrolyte in the anode region 101 is electrolyzed to deteriorated electrolyte, the poor electrolyte in the cathode region 102 is electrolyzed to poor electrolyte, at the moment, the deteriorated electrolyte in the anode region 101 is discharged from the anode port 4, the poor electrolyte in the cathode region 102 can flow through the separation net 3 to enter the anode region 101 to supplement the anode region 101 due to the liquid level difference, and new good electrolyte can be added from the cathode port 5 in the cathode region 102, so that the cycle can not only ensure that the electrolyte in the cathode region 102 is always good electrolyte, so as to improve the yield of metal lithium, but also can directly enter the anode region 101 for continuous use for electrolysis without other treatment, thereby realizing the reutilization of the poor electrolyte and reducing the production cost.

To facilitate removal of deteriorated electrolyte in the anode region 101 which has not been able to continue electrolysis anymore, while allowing electrolyte in the cathode region 102 to rapidly enter the anode region 101 to replenish electrolyte in the anode region 101, a siphon device is provided outside the anode port 4; the siphon device can be a siphon device formed by the existing siphon pump and a liquid suction pipe, or can be a siphon device described in a siphon device with a publication number of CN201241880Y, but the device needs to be high-temperature resistant; referring to fig. 1, when the siphon device is used, the anode port 4 is opened, the siphon pump 16 is opened after the suction pipe 15 of the siphon device is extended into the anode region 101, and when the siphon device pumps out the deteriorated electrolyte in the anode region 101, the electrolyte in the cathode region 102 flows to the anode region 101 due to suction force, so that the anode region is supplemented with electrolyte, and new electrolyte can be supplemented while the deteriorated electrolyte is pumped out, so that dynamic balance is achieved, and continuous electrolysis is realized.

The metallic lithium can be taken out manually and float the metallic lithium on the surface of the molten electrolyte and scooped out from the cathode opening 5, in order to avoid oxidation in the scooping-out process and conflict between the collected metallic lithium and the replenishing electrolyte, a guide pipe 12 is further arranged on the tank cover 9, the guide pipe 12 is positioned above the cathode region 102, one end of the guide pipe 12 stretches into the tank body 10 to be flush with the upper surface of the electrolyte in the cathode region 102, the other end of the guide pipe 12 is connected with the metallic lithium collecting chamber 13, and a lithium pump 14 for extracting the metallic lithium is further arranged on the guide pipe 12, so that the metallic lithium cannot be oxidized by contact with air in the transferring process, and the purity of the metallic lithium is ensured.

The particle size of the slag removed by the graphite anode 1 is measured by a plurality of times of electron microscopy, and referring to fig. 2, the particle size of the slag particles removed by the graphite anode 1 is found to be tens of micrometers at the minimum, most of the particle sizes are hundreds of micrometers to centimeters, and in order to effectively isolate the slag removed by the graphite anode 1, the mesh diameter of the separation net 3 is 10-10000 micrometers; the mesh diameter of the separation net 3 is too small, so that a better isolation effect can be achieved, but the manufacturing difficulty is high, the manufacturing cost is high, the mesh diameter of the separation net 3 is too large, and although a certain isolation effect can be achieved, the purity of the metallic lithium produced in the cathode region 102 is still influenced to a certain extent; the isolation amount of the separation net 3 to the slag material falling off from the graphite anode 1 reaches 95% when the diameter of the mesh hole of the separation net 3 is 10 mu m through multiple tests; when the mesh diameter of the separation net 3 is 100 mu m, the separation amount of the separation net 3 to the slag material falling off from the graphite anode 1 reaches 88%; when the mesh diameter of the separation net 3 is 1000 mu m, the separation amount of the separation net 3 to the slag material falling off from the graphite anode 1 reaches 84%; when the mesh diameter of the separation net 3 is 10000 mu m, the separation amount of the separation net 3 to the slag material fallen off from the graphite anode 1 reaches 70 percent.

For being convenient for change separates net 3, select different mesh diameter separate net 3 to use, separate net 3 can adopt the detachable connection mode setting such as grafting, mortise and tenon fourth of the twelve earthly branches to be covered on 9, for being convenient for make annular separate net and can be applicable to the high temperature state, separate net 3 and make by the stainless steel.

When a separation net 3 with larger mesh diameter is needed, a stainless steel separation net can be directly adopted; when the smaller mesh diameter screen 3 is needed, ceramic, polymer or fiber with small aperture is arranged in the stainless steel framework to adjust the mesh diameter of the screen 3, specifically, the stainless steel screen is made into a similar large woven mesh structure, the ceramic, polymer and fiber are directly sintered on the stainless steel framework during calcination, and the fiber can be directly bound on the stainless steel framework by using stainless steel wires; in addition, another arrangement mode can be adopted, stainless steel is made into the partition net which is of a double-layer structure, materials such as ceramic, polymer or fiber are filled in the middle of the double-layer structure, and then the double-layer structure is sintered in an interlayer to form an integrated structure. It should be noted that the above-mentioned ceramics, polymers or fibers are all made of a high temperature resistant material, and are prevented from being deformed by high temperature when the electrolyte is melted.

Since the upper end of the anode 1 is not abutted with the cell cover 9, in order to stably install the anode 1 in the electrolytic cell and ensure the stability of the electrolytic process, a refractory brick 11 is arranged above the bottom surface of the cell body 10, and the anode 1 is arranged in the cell body 10 through the refractory brick 11.

Claims (8)

1. The utility model provides a metal lithium electrolytic tank, includes cell body (10), cell body (10) top is equipped with lid (9), vertically be equipped with positive pole (1) in cell body (10), positive pole (1) bottom electrically conductive anode conductive plate (7) that is connected, positive pole (1) circumference is encircled and is provided with negative pole (2), negative pole (2) are electrically conductive with cell body (10) inner wall and are connected, cell body (10) outer wall electrically conductive cathode conductive plate (6) that is connected; the method is characterized in that: an annular separation net (3) is further arranged between the anode (1) and the cathode (2), the separation net (3) is circumferentially arranged on the anode (1) and divides the tank body (10) into an anode region (101) and a cathode region (102), the upper end of the separation net (3) is connected with a cover body (9), the lower end of the separation net (3) is abutted to the bottom surface of the tank body (10), a gas absorption pipeline (8), an anode opening (4) and a cathode opening (5) are arranged on the cover body (9), and the gas absorption pipeline (8) is positioned above the anode (1); the anode opening (4) and the cathode opening (5) can be closed, the anode opening (4) is positioned above the anode (1), and the cathode opening (5) is positioned above the cathode (2).

2. The metal lithium electrolytic cell according to claim 1, wherein: and a siphon device is arranged outside the anode port (4).

3. The metal lithium electrolytic cell according to claim 1, wherein: the lithium ion battery is characterized in that a guide pipe (12) is further arranged on the cover body (9), the guide pipe (12) is located above the cathode region (102), one end of the guide pipe (12) extends into the groove body (10), the other end of the guide pipe is connected with the metal lithium collecting chamber (13), and a lithium extraction pump (14) is further arranged on the guide pipe (12).

4. The metal lithium electrolytic cell according to claim 1, wherein: the diameter of the mesh of the separation net (3) is 10-10000 mu m.

5. The metal lithium electrolytic cell according to claim 4, wherein: the separation net (3) is detachably connected with the cover body (9), and the separation net (3) is made of stainless steel.

6. The metal lithium electrolytic cell according to claim 5, wherein: the pores on the separation net (3) are provided with ceramics, polymers or fibers.

7. The metal lithium electrolytic cell according to claim 5, wherein: the separation net (3) is of a double-layer structure, and ceramic, polymer or fiber is filled in the middle of the double-layer structure.

8. The metal lithium electrolytic cell according to claim 1, wherein: refractory bricks (11) are arranged above the bottom surface of the tank body (10), and the anode (1) is arranged in the tank body (10) through the refractory bricks (11).