A method and apparatus for removing impurities from high-purity fluorinated liquid by ionization

Abstract

This invention relates to the field of high-purity chemical impurity removal technology, specifically to a method and apparatus for ion-based impurity removal from high-purity fluorinated liquids. The method comprises the following steps: adding an exchange-adsorbent material to a container holding the fluorinated liquid, then adding ultrapure water, adsorbing and removing impurities, and separating the impurities. By adding ultrapure water, a layer of aqueous phase is formed on top of the fluorinated liquid. The exchange-adsorbent material is located between the aqueous phase and the organic phase of the fluorinated liquid. Impurity ions in the fluorinated liquid migrate to the more easily ionized aqueous phase after contacting the phase interface, and are then adsorbed by the exchange-adsorbent material, achieving the effect of ion-based impurity removal. This invention solves the problem of incompatibility between fluorinated liquids and exchange-adsorbent materials such as resins, achieving effective impurity removal from high-purity fluorinated liquids.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of impurity removal of high-purity chemicals, and particularly relates to a method and device for removing impurities from high-purity fluorinated liquid. BACKGROUND

[0002] In the semiconductor and display panel industry, fluorine chemicals and materials can be used as fluorine solvents, cleaning agents, heat-conducting liquids, etching materials, photosensitive materials, etc. due to their special properties, and are key materials in the industry. Since fluorides are used in the semiconductor field, the product purity needs to meet the electronic grade requirement, and the metal ions need to be purified to <0.1 ppb. The conventional ion removal method is ion exchange, that is, ion exchange resin is used to purify by column, but since the chemical structure of the fluorinated liquid is perfluorinated, it is hydrophobic and not compatible with the ion exchange resin. When the fluorinated liquid flows in, the ion exchange resin floats above the fluorinated liquid, and the fluorinated liquid is difficult to adhere to the surface of the ion exchange resin. This method cannot fully immerse to exchange ions, and the conventional column method has limited effect on the removal of metal impurities. SUMMARY

[0003] To solve the technical problem of incompatibility between fluorinated liquid and resin, the present application provides a method and device for removing impurities from high-purity fluorinated liquid, which achieves the effect of ion removal and purification.

[0004] The present application adopts the following technical solutions:

[0005] On the one hand, the present application provides a method for removing impurities from high-purity fluorinated liquid, comprising the following steps: adding exchange adsorption material in a container containing fluorinated liquid, then adding ultrapure water, adsorbing and removing impurities, and separating.

[0006] Further, the exchange adsorption material is any one of ion exchange resin, ion exchange membrane, activated carbon, and activated alumina.

[0007] Further, the exchange adsorption material is ion exchange resin, and the addition amount of the ion exchange resin is 0.1-10wt% of the content of the fluorinated liquid.

[0008] Further, the ion exchange resin is any one or several of cation resin, anion resin, boron-removing resin, polishing resin, chelating resin, and adsorbing resin.

[0009] Further, the addition amount of the ultrapure water is at least to immerse or cover the exchange adsorption material.

[0010] Further, the standing time is 0.5-10h.

[0011] In another aspect, the application also provides a high-purity fluoride liquid ion impurity removal device, comprising a reaction kettle, a feed inlet, and a discharge outlet, wherein n groups of partitions are arranged in parallel from the top to the bottom in the reaction kettle to divide the reaction kettle into (n+1) cavities, n>=0, and the distance between the lowest end of the partition and the bottom of the reaction kettle is less than the addition height of the fluoride liquid; the fluoride liquid, the exchange adsorption material, and ultrapure water are added from the feed inlet, and the fluoride liquid after adsorption and impurity removal is discharged from the discharge outlet.

[0012] Further, a screen is arranged horizontally in the reaction kettle, the distance between the screen and the bottom of the reaction kettle is less than the addition height of the fluoride liquid, and the exchange adsorption material is located above the screen.

[0013] Further, a column is arranged in the cavity, and any one or several of a stirring device, a shaking device, and an ultrasonic device are arranged on the column.

[0014] Further, the feed inlet and the discharge outlet are oppositely arranged in the reaction kettle; the feed inlet comprises a fluoride liquid feed inlet and a water inlet, the discharge outlet comprises a fluoride liquid discharge outlet and a water outlet; the fluoride liquid feed inlet is located at the lower end of the side wall of the reaction kettle, the fluoride liquid discharge outlet is located at the lower end of the side wall on the opposite side of the fluoride liquid feed inlet; the water inlet is located at the upper end of the side wall of the reaction kettle, and the water outlet is located at the upper end of the side wall on the opposite side of the water inlet.

[0015] The high-purity fluoride liquid ion impurity removal method of the application can cover a layer of water phase above the fluoride liquid by adding ultrapure water, the exchange adsorption material is located between the water phase and the organic phase of the fluoride liquid, the impurity ions in the fluoride liquid migrate to the water phase which is more easily ionized after contacting the phase interface, and then are adsorbed by the exchange adsorption material, thereby achieving the effect of ion impurity removal. The application solves the problem of incompatibility between the fluoride liquid and the exchange adsorption material such as resin, can reduce the impurity content of ppb level by one order of magnitude, and realizes effective impurity removal of high-purity fluoride liquid.

[0016] The high-purity fluoride liquid ion impurity removal device of the application does not increase the operation cost on the basis of solving the compatibility problem compared with the traditional ion exchange column equipment, and can integrate multiple exchange adsorption functions into one after being divided into multiple cavities, which is more economical. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the application, and those skilled in the art can obtain other drawings according to these drawings without any creative effort.

[0018] Figure 1 is a structure diagram of the intermittent purification device in the embodiment of the present application;

[0019] Figure 2 is a structure diagram of the continuous purification device in another embodiment of the present application;

[0020] In the figure: 1-reaction kettle, 2-feed inlet, 3-discharge outlet, 4-baffle, 5-cavity, 6-sieve, 7-column, 8-water inlet, 9-fluorination liquid feed inlet, 10-fluorination liquid discharge outlet, 11-water outlet, 12-resin, 13-water layer, 14-fluorination liquid layer, 15-fluorination liquid / water phase interface, 16-feeding cover. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings of the specification. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the protection scope of the present application.

[0022] The method for removing impurity ions from high-purity fluorination liquid in the present application comprises the following steps: adding exchange adsorption material in a container containing fluorination liquid, adding ultrapure water, adsorbing and removing impurities, and separating. By adding ultrapure water, a water phase is formed on the fluorination liquid according to the hydrophobic property of the fluorination liquid and the density difference between the fluorination liquid and the ultrapure water. The exchange adsorption material is located between the water phase and the organic phase of the fluorination liquid. The impurity ions in the fluorination liquid migrate to the water phase which is more easily ionized after contacting the phase interface, and are then adsorbed by the exchange adsorption material, achieving the effect of removing ions. At the same time, since fluorides with low molecular weight are extremely volatile, the formation of a water phase on the fluorination liquid for liquid sealing can effectively reduce the volatilization of the fluorination liquid during the purification process, thereby reducing the loss of the material liquid.

[0023] Specifically, in some embodiments of the present application, the exchange adsorption material is any one of ion exchange resin, ion exchange membrane, activated carbon, and activated alumina. When the exchange adsorption material is an ion exchange membrane, a layer of ion exchange membrane is uniformly covered at the phase interface of the fluorination liquid, and then ultrapure water is added. Since the high molecular membrane material can simultaneously have hydrophilic and oleophilic properties, it can enhance the compatibility between the phases while adsorbing ion impurities.

[0024] Preferably, the exchange adsorption material is ion exchange resin. A water phase layer is covered above the fluorination liquid, the resin is filled in the water phase due to its higher wettability in ultra-pure water, and the resin is concentrated on the side of the water phase at the interface between the water phase and the organic phase of the fluorination liquid due to the density difference, the water phase and the fluorination liquid have a larger phase interface in contact in the container, the anions and cations in the fluorination liquid migrate to the water phase which is more easily ionized after contacting the phase interface, and then are adsorbed by the resin soaked in the water phase after entering the water phase, so as to achieve the ion removal effect.

[0025] Specifically, in some embodiments of the present application, the exchange adsorption material is ion exchange resin, and the addition amount of the ion exchange resin is 0.1-10wt% of the content of the fluorination liquid. More specifically, the addition amount of the ion exchange resin is 0.1wt%, 0.5wt%, 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, or 10wt% of the content of the fluorination liquid. More preferably, the addition amount of the ion exchange resin is 2wt% of the content of the fluorination liquid.

[0026] Specifically, in some embodiments of the present application, the ion exchange resin is any one or several of cation resin, anion resin, boron removal resin, polishing resin, chelating resin, and adsorption resin. Different ion exchange resins can be used alone for removal of specific impurities, or can be used continuously in a set of devices for removal of multiple impurities. The type of ion exchange resin can be changed according to product requirements, and all belong to the protection scope of the present application.

[0027] Specifically, in some embodiments of the present application, the addition amount of the ultra-pure water is at least to immerse or cover the exchange adsorption material.

[0028] Specifically, in some embodiments of the present application, the standing time is 0.5-10h. More specifically, the standing time is 0.5h, 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, or 10h. More preferably, the standing time is 2h.

[0029] The present application also provides a device for removing ions from high-purity fluorination liquid, which comprises a container, an exchange adsorption material, and ultra-pure water. Figures 1-2As shown, it comprises a reaction kettle 1, a feed inlet 2, and a discharge outlet 3, a plurality of n sets of partitions 4 are arranged in parallel from the top to the bottom in the reaction kettle 1, so as to divide the reaction kettle 1 into (n+1) cavities 5, n≥0, the distance between the lowest end of the partition 4 and the bottom of the reaction kettle 1 is less than the adding height of the fluorinated liquid; the fluorinated liquid, the exchange adsorption material, and the ultrapure water are added from the feed inlet 2, and the fluorinated liquid after impurity removal is discharged from the discharge outlet 3. The arrangement of the partition 4 divides the reaction kettle into a plurality of cavities 5, different exchange adsorption materials can be added in different cavities 5, different types of impurity ions are adsorbed, and the multi-stage column effect in the conventional metal impurity removal mode can be realized in one reaction kettle. Specifically, the number of partitions can be increased or decreased according to requirements, for example, when combined with other adsorption materials, more partitions can be added in series, therefore, the maximum number of partitions is not limited in the application. Preferably, 0≤n≤3 from the perspective of cost and equipment setting difficulty.

[0030] Specifically, in some embodiments of the application, a screen 6 is arranged horizontally in the reaction kettle, the distance between the screen 6 and the bottom of the reaction kettle 1 is less than the adding height of the fluorinated liquid, and the exchange adsorption material is located on the upper part of the screen 6. The arrangement of the screen 6 ensures that the exchange adsorption material, especially the ion exchange resin, can quickly be located at the interface between the organic phase and the aqueous phase for adsorption when the fluorinated liquid or water is added. More specifically, the distance between the screen 6 and the bottom of the reaction kettle 1 is greater than the distance between the lowest end of the partition 4 and the bottom of the reaction kettle 1, so as to ensure that the exchange adsorption materials on the screen 6 in different cavities 5 are independent of each other, and the adsorption of different ions in different cavities 5 is realized.

[0031] Specifically, in some embodiments of the application, a column stand 7 is arranged in the cavity, and any one or several of a stirring device, a shaking device, and an ultrasonic device is arranged on the column stand 7. By arranging the column stand 7, the fluorinated liquid flows along a tortuous path in the reaction kettle 1, so as to reduce the dead volume and the back mixing of the liquid in the reaction kettle 1. At the same time, the addition of the stirring device, the shaking device, and the ultrasonic device helps to further increase the mass transfer rate of ion exchange. The structure of the stirring device, the shaking device, and the ultrasonic device is not specially limited in the application, any device that can realize the effects of stirring, shaking, and ultrasonic is within the protection scope of the application; at the same time, the addition of other conventional devices that help to increase the mass transfer rate of ion exchange is also within the protection scope of the application.

[0032] Specifically, in some embodiments of the present application, the feed inlet 2 and the discharge outlet 3 are oppositely arranged in the reactor 1; the feed inlet 2 comprises a water inlet 8 and a fluorination liquid inlet 9, and the discharge outlet 3 comprises a fluorination liquid outlet 10 and a water outlet 11; the fluorination liquid inlet 9 is located at the lower end of the side wall of the reactor 1, the fluorination liquid outlet 10 is located at the lower end of the side wall opposite to the fluorination liquid inlet 9, the water inlet 8 is located at the upper end of the side wall of the reactor 1, and the water outlet 11 is located at the upper end of the side wall opposite to the water inlet 8. The fluorination liquid inlet is located at the lower end of the side wall, and during the feeding process, the fluorination liquid flows in the reactor 1 in a zigzag manner through the column 7 and the stirring device, so as to reduce the dead volume in the reactor 1; and according to the density difference, the purified fluorination liquid flows out from the lower end outlet, and the water flows into and out of the reactor 1 from the upper end, so that the ion exchange resin and the fluorination liquid are fully contacted at the junction of the water phase and the fluorination liquid phase.

[0033] As an embodiment of the present application, as shown in Figure 1 n = 0, that is, in a single reactor, which belongs to a batch purification device. The fluorination liquid to be purified is added from the feed inlet 2, then the resin 12 is added, and then the ultrapure water is added, and the water layer 13 is located above the fluorination liquid layer 14, the resin 12 is filled in the water phase and is concentrated on the water phase side at the fluorination liquid / water phase interface 15, and the ion exchange is fully carried out after standing for a period of time, and the fluorination liquid after ion exchange is discharged from the discharge outlet 3. Specifically, the addition amount of the fluorination liquid is 0-80% of the volume of the reactor, preferably, the addition amount is 2 / 3 of the volume of the reactor; the amount of ultrapure water added is just enough to immerse the resin, and preferably, the amount of ultrapure water is 10wt% of the addition amount of the fluorination liquid. The batch operation in this embodiment completes the purification amount at one time, and the ultrapure water and the resin can be reused, and the next batch of liquid is added, and the fluorination liquid is directly added from the feed inlet, and the addition amount is the same as the first batch, and the fluorination liquid is re-layered with water and resin due to the density difference to achieve the state after the first batch is added. Through different resins, this embodiment can realize the removal of single type impurities such as cation impurities and anion impurities.

[0034] As an embodiment of the present application, as shown in Figure 2As shown, n = 3, the reactor 1 is divided into multiple cavities 5, for the integrated continuous purification device of multiple resins. Four cavities are used from left to right as cation resin, anion resin, boron removal resin, polishing resin as exchange adsorption material, and the fluorination liquid is purified to remove anions and boron elements. Specifically, a feeding cover 16 is arranged at the top of each cavity 5, and the cation resin, anion resin, boron removal resin and polishing resin are added to the reactor 1 from the feeding cover 16, the fluorination liquid outlet 10 is closed, and the water outlet 11 is opened; the fluorination liquid is slowly introduced from the fluorination liquid inlet 9 to the fluorination liquid layer 14, and the liquid level is slightly higher than the screen 6, at this time the resin 12 floats above the fluorination liquid layer 14; the ultrapure water is added from the water inlet 8, and the space of the upper water layer 13 is slowly filled until the water outlet 11 is opened, and the fluorination liquid is circulated back to the fluorination liquid inlet 9, and the adsorption and impurity removal are performed for a period of time, and then the purified fluorination liquid is discharged from the fluorination liquid outlet. The continuous device of the embodiment can realize the adsorption of multiple types of ion impurities at one time, and the content of the purified fluorination liquid flowing out is the added amount, that is, the purification of the fluorination liquid with the corresponding content is completed; continue to add the corresponding mass of fluorination liquid, and repeat the above adsorption process, that is, the continuous purification can be realized.

[0035] More specifically, in the continuous purification device, the addition amount of the fluorination liquid is 0-90% of the volume of the reactor, preferably, the addition amount of the fluorination liquid is 3 / 4 of the volume of the reactor; and the remaining volume of the device is filled with ultrapure water.

[0036] The continuous purification device of the present application can use multiple resins in one system to achieve multiple ion removal effects in one device; compared with the traditional ion exchange column device, the operation cost is not increased on the basis of solving the compatibility problem, and multiple resin purification functions can be integrated, which is more economical.

[0037] The ion impurity removal method of the present application can solve the problem of incompatibility between the resin and the fluorination liquid, and can achieve the effect of removing ions in the fluorination liquid. The fluorination liquid treated by the process, such as the ion impurity of the fluorination liquid raw material, can reach 10ppb or less after purification; when the ion impurity of the raw material is 10ppb or less, the metal ion and B element can reach 1ppb or less; under the condition of further prolonging the treatment time in the continuous purification device, the purity of the fluorination liquid can reach G4 level, that is, the metal ion and B element will be less than 0.1ppb. Specifically, the present application does not limit the prolonged purification treatment time, and the treatment time can be prolonged as much as possible to improve the purification effect. Preferably, considering the timeliness and purification efficiency of the purification process, the purification treatment time is 0.5-10h.

[0038] The fluorinated liquid of the present invention is a fluoride such as perfluorohydroether, perfluoropolyether, or perfluoroester. In addition to the fluorinated liquid, other exchange adsorption substances such as resins and water-incompatible organic substances, such as perchlorinated compounds and fluorochlorinated compounds, can be purified by the method and apparatus described in the present invention, and all fall within the protection scope of the present invention.

[0039] The present invention will be further described below with reference to specific embodiments.

[0040] Example 1

[0041] This embodiment adopts Figure 1 The intermittent purification apparatus shown involves adding fluorinated liquid to the reactor until it reaches 2 / 3 of its volume, then adding cation exchange resin (2 wt% of the fluorinated liquid content) and ultrapure water (10 wt% of the fluorinated liquid content). After standing for 2 hours, the fluorinated liquid is discharged from the outlet to achieve separation. ICP-MS and IC are tested to determine the ion purification and impurity removal status.

[0042] Example 2

[0043] This embodiment adopts Figure 1 The intermittent purification apparatus shown involves adding fluorinated liquid to the reactor until it reaches 2 / 3 of its volume, then adding chelating resin at 2 wt% of the fluorinated liquid content, and finally adding ultrapure water at 10 wt% of the fluorinated liquid content. After standing for 2 hours, the fluorinated liquid is discharged from the outlet to achieve separation. ICP-MS and IC are tested to determine the ion purification and impurity removal status.

[0044] Example 3

[0045] This embodiment adopts Figure 1 The intermittent purification apparatus shown involves adding fluorinated liquid to the reactor until it reaches 2 / 3 of its volume, then adding anion exchange resin at 2 wt% of the fluorinated liquid content, and then adding ultrapure water at 10 wt% of the fluorinated liquid content. After standing for 2 hours, the fluorinated liquid is discharged from the outlet to achieve separation. ICP-MS and IC are tested to determine the ion purification and impurity removal status.

[0046] Example 4

[0047] This embodiment adopts Figure 1 The intermittent purification apparatus shown involves adding fluorinated liquid to the reactor until it reaches 2 / 3 of its volume, then adding 0.1 wt% of cation exchange resin and 10 wt% of ultrapure water. After standing for 2 hours, the fluorinated liquid is discharged from the outlet to achieve separation. ICP-MS and IC are tested to determine the ion purification and impurity removal status.

[0048] Example 5

[0049] This embodiment adopts Figure 1The intermittent purification device shown, the fluorination liquid is added to the reaction kettle to 2 / 3 of the volume of the reaction kettle, then 10wt% of the cationic resin content of the fluorination liquid is added, 10wt% of the ultrapure water content of the fluorination liquid is added, and the fluorination liquid is discharged from the discharge port to realize separation after 2h of standing; ICP-MS and IC are tested to judge the ion purification and impurity removal.

[0050] Example 6

[0051] This example uses Figure 1 The intermittent purification device shown, the fluorination liquid is added to the reaction kettle to 2 / 3 of the volume of the reaction kettle, then 10wt% of the cationic resin content of the fluorination liquid is added, 10wt% of the ultrapure water content of the fluorination liquid is added, and the fluorination liquid is discharged from the discharge port to realize separation after 2h of standing; ICP-MS and IC are tested to judge the ion purification and impurity removal.

[0052] Example 7

[0053] This example uses Figure 1 The intermittent purification device shown, the fluorination liquid is added to the reaction kettle to 2 / 3 of the volume of the reaction kettle, then 10wt% of the cationic resin content of the fluorination liquid is added, 10wt% of the ultrapure water content of the fluorination liquid is added, and the fluorination liquid is discharged from the discharge port to realize separation after 2h of standing; ICP-MS and IC are tested to judge the ion purification and impurity removal.

[0054] Example 8

[0055] This example uses Figure 1 The intermittent purification device shown, the fluorination liquid is added to the reaction kettle to 2 / 3 of the volume of the reaction kettle, then 10wt% of the cationic resin content of the fluorination liquid is added, 10wt% of the ultrapure water content of the fluorination liquid is added, and the fluorination liquid is discharged from the discharge port to realize separation after 2h of standing; ICP-MS and IC are tested to judge the ion purification and impurity removal.

[0056] Comparative Example 1

[0057] This comparative example uses an ion exchange column to purify the fluorination liquid by column, the cation exchange resin is filled in the resin column, the height-diameter ratio is 10:1, the fluorination liquid is purified by column, and ICP-MS and IC are tested to judge the ion purification and impurity removal after the fluorination liquid is purified.

[0058] Comparative Example 2

[0059] This comparative example uses Figure 1 The intermittent purification device shown, the fluorination liquid is added to the reaction kettle to 2 / 3 of the volume of the reaction kettle, then 10wt% of the cationic resin content of the fluorination liquid is added, 10wt% of the ultrapure water content of the fluorination liquid is added, and the fluorination liquid is discharged from the discharge port to realize separation after 2h of standing; ICP-MS and IC are tested to judge the ion purification and impurity removal.

[0060] Comparative Example 3

[0061] The comparative example uses the intermittent purification device shown in Figure 1 The comparative example uses the intermittent purification device shown in

[0062] Comparative Example 4

[0063] The comparative example uses the intermittent purification device shown in Figure 1 The comparative example uses the intermittent purification device shown in

[0064] Comparative Example 5

[0065] The comparative example uses the intermittent purification device shown in Figure 1 The comparative example uses the intermittent purification device shown in

[0066] Example 9

[0067] The example uses the continuous purification device shown in Figure 2 The example uses the continuous purification device shown in

[0068] Example 10

[0069] The example uses the continuous purification device shown in Figure 2The continuous purification device shown, select the reaction kettle with 4 cavities, from left to right into the cavity in turn cation resin, anion resin, boron removal resin, polishing resin, resin on the screen, from the fluorinated liquid feed port to add fluorinated liquid to the volume of 3 / 4 of the reaction kettle, the amount of each resin is 0.1wt% of the fluorinated liquid content, then add ultrapure water from the water inlet to the reaction kettle is filled; open the fluorinated liquid discharge port, the fluorinated liquid circulating back to the fluorinated liquid feed port, circulating 2h to adsorb impurities, then the purified fluorinated liquid from the fluorinated liquid discharge port; test ICP-MS and IC to determine the ion purification and impurity removal.

[0070] Example 11

[0071] This example uses Figure 2 The continuous purification device shown, select the reaction kettle with 4 cavities, from left to right into the cavity in turn cation resin, anion resin, boron removal resin, polishing resin, resin on the screen, from the fluorinated liquid feed port to add fluorinated liquid to the volume of 3 / 4 of the reaction kettle, the amount of each resin is 0.1wt% of the fluorinated liquid content, then add ultrapure water from the water inlet to the reaction kettle is filled; open the fluorinated liquid discharge port, the fluorinated liquid circulating back to the fluorinated liquid feed port, circulating 2h to adsorb impurities, then the purified fluorinated liquid from the fluorinated liquid discharge port; test ICP-MS and IC to determine the ion purification and impurity removal.

[0072] Example 12

[0073] This example uses Figure 2 The continuous purification device shown, and the screen is removed. Select the reaction kettle with 4 cavities, from left to right into the cavity in turn cation resin, anion resin, boron removal resin, polishing resin, from the fluorinated liquid feed port to add fluorinated liquid to the volume of 3 / 4 of the reaction kettle, the amount of each resin is 2wt% of the fluorinated liquid content, then add ultrapure water from the water inlet to the reaction kettle is filled; open the fluorinated liquid discharge port, the fluorinated liquid circulating back to the fluorinated liquid feed port, circulating 2h to adsorb impurities, then the purified fluorinated liquid from the fluorinated liquid discharge port; test ICP-MS and IC to determine the ion purification and impurity removal.

[0074] Comparative Example 6

[0075] This example uses Figure 2The continuous purification device shown in the drawing is used, the partition is removed, the cationic resin, the anionic resin, the boron removal resin and the polishing resin are mixed and loaded into the reaction kettle, the resins are located on the screen, the fluorinated liquid is added from the fluorinated liquid feeding port to 3 / 4 of the volume of the reaction kettle, the addition amount of each resin is 2wt% of the fluorinated liquid content, and then ultrapure water is added from the water inlet to fill the reaction kettle; open the fluorinated liquid discharge port, circulate the outflowing fluorinated liquid back to the fluorinated liquid feeding port, circulate for 2h to adsorb impurities, and then discharge the purified fluorinated liquid from the fluorinated liquid discharge port; test ICP-MS and IC to judge the ion purification and impurity removal.

[0076] The test results of examples 1-12 and comparative examples 1-6 are shown in table 1.

[0077] Table 1

[0078]

[0079]

[0080] As shown in examples 1-12, by the ion impurity removal method of the present application, the effect of removing ions in the fluorinated liquid can be achieved. Specifically, as shown in examples 1-8, when using an intermittent purification device, using a specific resin for the adsorption of a specific ion has a better adsorption effect; as can be seen from the comparison of example 1 and comparative example 1, the traditional column method, due to the difficulty of the fluorinated liquid to adhere to the surface of the ion exchange resin, it is difficult to exchange ions; in comparative example 2, no ultrapure water is added, the resin is not compatible with the fluorinated liquid, and effective adsorption is difficult; in comparative example 3, no resin is added, only part of the ions at the phase interface migrate to the water phase which is more easily ionized, and the purification effect is limited. As can be seen from examples 1, examples 4-5 and comparative examples 4-5, when the amount of resin added is too small, the purification effect is limited; when the amount of resin added is too large, the difference in purification effect is not large; the preferred amount of resin added is 0.1-10wt% of the fluorinated liquid content.

[0081] As shown in examples 9-12, when using a continuous purification device, the anions, cations and boron elements in the fluorinated liquid can be purified at the same time. As can be seen from the comparison of example 9 and example 12, by increasing the contact area of the fluorinated liquid and the ultrapure water, the ion impurity removal effect can be improved; at the same time, as can be seen from the comparison of example 9 and comparative example 6, the effect of sequentially adsorbing specific impurities in each cavity is better than the purification effect of mixed resins.

[0082] The above describes the present application with the help of specific examples, but it should be understood that the specific description here should not be understood as limiting the essence and scope of the present application, and various modifications of the above examples made by those skilled in the art after reading the present specification are within the scope of the present application.

Claims

1. A method for impurity removal from a high purity fluoride liquid ion, characterized in that, The method comprises the following steps: adding exchange adsorption material into a container containing fluorination liquid, and then adding ultrapure water to adsorb and remove impurities and separate; the exchange adsorption material is ion exchange resin, and the addition amount of the ion exchange resin is 0.1-10wt% of the content of the fluorination liquid; the exchange adsorption material is located between the water phase and the organic phase of the fluorination liquid.

2. The method of claim 1, wherein the high purity fluoride liquid ion is selected from the group consisting of potassium fluoride, sodium fluoride, lithium fluoride, rubidium fluoride, cesium fluoride, and combinations thereof. The ion exchange resin is any one or several of cation resin, anion resin, boron-removing resin, polishing resin, chelating resin and adsorbing resin.

3. The method of claim 1, wherein the high purity fluoride liquid ion is selected from the group consisting of potassium fluoride, sodium fluoride, lithium fluoride, rubidium fluoride, cesium fluoride, and combinations thereof. The addition amount of the ultrapure water is at least to immerse or cover the exchange adsorption material.

4. The method of claim 1, wherein the high purity fluoride liquid ion is selected from the group consisting of potassium fluoride, sodium fluoride, lithium fluoride, rubidium fluoride, cesium fluoride, and combinations thereof. The time for adsorbing and removing impurities is 0.5-10h.

5. A high purity fluoride liquid ion impurity removal device, characterized in that, The method comprises a reaction kettle, a feed inlet and a discharge outlet, n sets of partitions are arranged in the reaction kettle from the top to the bottom in parallel to divide the reaction kettle into (n+1) cavities, n≥0, the distance between the lowest end of the partition and the bottom of the reaction kettle is less than the addition height of the fluorination liquid; the fluorination liquid, the exchange adsorption material and the ultrapure water are added from the feed inlet, and the fluorination liquid after adsorbing and removing impurities is discharged from the discharge outlet; a screen is arranged horizontally in the reaction kettle, the distance between the screen and the bottom of the reaction kettle is less than the addition height of the fluorination liquid, and the exchange adsorption material is located on the upper part of the screen; the distance between the screen and the bottom of the reaction kettle is greater than the distance between the lowest end of the partition and the bottom of the reaction kettle; the exchange adsorption material is ion exchange resin, and the addition amount of the ion exchange resin is 0.1-10wt% of the content of the fluorination liquid.

6. The high purity fluoride liquid ion removal device of claim 5, wherein, A column is arranged in the cavity, and any one or several of a stirring device, a shaking device and an ultrasonic device are arranged on the column.

7. The high purity fluoride liquid ion removal device of claim 5, wherein, The feed inlet and the discharge outlet are arranged oppositely in the reaction kettle; the feed inlet comprises a fluorination liquid feed inlet and a water inlet, and the discharge outlet comprises a fluorination liquid discharge outlet and a water outlet; the fluorination liquid feed inlet is located at the lower end of the side wall of the reaction kettle, and the fluorination liquid discharge outlet is located at the lower end of the side wall on the side opposite to the fluorination liquid feed inlet; the water inlet is located at the upper end of the side wall of the reaction kettle, and the water outlet is located at the upper end of the side wall on the side opposite to the water inlet.

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