Method and system for refining hydrogen peroxide water

Abstract

The present invention relates to a method and a system for purifying hydrogen peroxide water, which can reduce the re-elution of ions during the purification process by preventing the layer separation of a mixed ion exchange resin in which a cation exchange resin and an anion exchange resin are mixed, thereby satisfying the purity required in the precision chemistry field such as the semiconductor industry field. The method for purifying hydrogen peroxide water comprises: (a) a step for producing a mixed ion exchange resin by injecting a gas into a mixture of a cation exchange resin, an anion exchange resin, and water and bubbling; (b) passing hydrogen peroxide water through the mixed ion exchange resin; and (c) discharging the hydrogen peroxide water that has passed through the mixed ion exchange resin.

Description

Technical Field

[0001] The present invention relates to a method and system for purifying hydrogen peroxide water by passing hydrogen peroxide water through an ion exchange resin for purification. Background Art

[0002] Hydrogen peroxide is easily soluble in water, ethanol, and ether. It partially dissociates hydrogen ions in aqueous solution and becomes weakly acidic. Since it has strong oxidizing power, it is used as an oxidizing agent in various fields. In particular, hydrogen peroxide is used for cleaning semiconductor wafers and etching in semiconductor and display manufacturing processes. In this case, high-purity hydrogen peroxide with extremely limited impurities is required.

[0003] However, when commercially available hydrogen peroxide is used directly, it is difficult to produce high-quality products because of the high concentration of impurities in hydrogen peroxide, which may damage semiconductors. Therefore, in the field of fine chemicals such as the semiconductor industry, high-purity hydrogen peroxide is required.

[0004] Conventionally, as a method for purifying hydrogen peroxide, there is a method of purifying and concentrating by distillation in a column made of aluminum or special steel filled with a filler, but there is a problem that various metal ions such as aluminum ions are contained.

[0005] As other methods for reducing impurities in hydrogen peroxide water, a method using a reverse osmosis membrane and a method using an ion exchange resin have been proposed. However, the method using a reverse osmosis membrane has the problem that the reverse osmosis membrane will deteriorate and the supporting capacity will decrease as the high-concentration hydrogen peroxide water continues to contact the reverse osmosis membrane. In the method using an ion exchange resin, due to the reaction between hydrogen peroxide and the ion exchange resin, oxygen and the like will be generated, which poses a risk of explosion, and therefore it is necessary to improve the process stability.

[0006] On the other hand, Japanese Patent Publication No. 1996-143303 discloses a method for purifying hydrogen peroxide water, which uses a mixed ion exchange resin composed of a cation exchange resin and an anion exchange resin to remove dissociative impurities. However, there is a problem that the impurity concentration in the purified hydrogen peroxide water is still high and cannot meet the purity required in the field of fine chemicals.

[0007] Therefore, it is necessary to develop a method and system for purifying hydrogen peroxide water that can satisfy the purity required in the field of fine chemicals such as the semiconductor industry.

[0008] Prior art literature

[0009] Patent Literature

[0010] Patent Document 1: Japanese Patent Publication No. 1996-143303 Summary of the invention

[0011] Issues to be solved

[0012] An object of the present invention is to provide a method and system for purifying hydrogen peroxide water, which can reduce the re-elution of ions during the purification process by preventing the layer separation of a mixed ion exchange resin formed by mixing a cation exchange resin and an anion exchange resin, thereby satisfying the purity required in the field of fine chemicals such as the semiconductor industry.

[0013] Another object of the present invention is to provide a method and system for purifying hydrogen peroxide water, which can stably discharge the gas generated by the reaction between hydrogen peroxide and ion exchange resin to reduce the risk of explosion, and can constantly maintain the liquid level of hydrogen peroxide water in a refining tower to improve process stability.

[0014] Another object of the present invention is to provide a method and system for purifying hydrogen peroxide solution, which can increase the purification capacity and purification speed without excessively expanding the equipment, thereby improving productivity.

[0015] Another object of the present invention is to provide a method and system for purifying hydrogen peroxide solution, which can prevent the catalytic reaction caused by drying of the ion exchange resin in the purification tower, thereby reducing unintended gas generation and further improving the ion exchange performance.

[0016] However, the problems to be solved by the present application are not limited to the problems mentioned above, and a person skilled in the art should be able to clearly understand other problems not mentioned through the following description.

[0017] Solution to the problem

[0018] In order to solve the above-mentioned problems, the present invention provides a method for purifying hydrogen peroxide water, which comprises: (a) a step of injecting gas into a mixture of a cation exchange resin, an anion exchange resin and water and bubbling the mixture to produce a mixed ion exchange resin; (b) a step of passing the hydrogen peroxide water through the mixed ion exchange resin; and (c) a step of discharging the hydrogen peroxide water that has passed through the mixed ion exchange resin.

[0019] According to one embodiment of the present invention, in the above step (a), the volume of water (V W ) and the total volume of the cation exchange resin and the anion exchange resin (V R ) ratio (V W / V R ) can be from 0.1 to 0.3.

[0020] According to one embodiment of the present invention, the above step (a) is carried out in a resin mixing tank, and after the above step (a) and before the above step (b), it may further include the step of (a-2) injecting the above-produced mixed ion exchange resin into a refining tower.

[0021] According to one embodiment of the present invention, the cation exchange resin and the anion exchange resin may be included in a volume ratio of 0.8:1.0 to 1.0:0.8.

[0022] According to one embodiment of the present invention, in the above step (a), the resistivity of the water may be greater than 18 MΩ·cm.

[0023] According to one embodiment of the present invention, in the above step (a), the gas may be an unreactive gas or air.

[0024] According to one embodiment of the present invention, the non-reactive gas may be selected from nitrogen, helium, neon, argon, krypton, xenon and SF 6 One or more of the groups consisting of.

[0025] According to one embodiment of the present invention, in the above step (a), the gas may be heated at 0.5 to 1.5 kgf / cm 2 pressure injection.

[0026] According to one embodiment of the present invention, the above step (a) can be performed for more than 24 hours.

[0027] According to one embodiment of the present invention, after the above step (c), the method may further include: (d) transferring the hydrogen peroxide solution discharged in the above step (c) to an intermediate storage tank; and (e) transferring the hydrogen peroxide solution in the above intermediate storage tank to a subsequent process or a final storage tank via a transfer pipe equipped with a pump.

[0028] According to one embodiment of the present invention, the liquid level of the hydrogen peroxide solution in the intermediate storage tank may be greater than 30% of the internal height of the intermediate storage tank.

[0029] According to one embodiment of the present invention, in the step (e), the pump may provide the transfer thrust.

[0030] In addition, the present invention provides a purification system for hydrogen peroxide solution, comprising a purification tower equipped with a gas injection pipe and a discharge pipe provided at the rear end of the purification tower, wherein after a mixture of a cation exchange resin, an anion exchange resin and water is introduced into the purification tower, a gas is injected through the gas injection pipe and bubbled to produce a mixed ion exchange resin, and hydrogen peroxide solution is introduced into the purification tower to pass through the mixed ion exchange resin.

[0031] In addition, the present invention provides a purification system for hydrogen peroxide solution, comprising a resin mixing tank having a gas injection pipe and a resin transfer pipe, a refining tower provided at the rear end of the resin mixing tank, and a discharge pipe provided at the rear end of the refining tower, wherein after a mixture of a cation exchange resin, an anion exchange resin and water is introduced into the resin mixing tank, a gas is injected and bubbled through the gas injection pipe to produce a mixed ion exchange resin, the produced mixed ion exchange resin is injected into the refining tower through the resin transfer pipe, and hydrogen peroxide solution is introduced into the refining tower to pass through the mixed ion exchange resin.

[0032] According to one embodiment of the present invention, in the above mixture, the volume of water (V W ) and the total volume of the cation exchange resin and the anion exchange resin (V R ) ratio (V W / V R ) can be from 0.1 to 0.3.

[0033] According to one embodiment of the present invention, the cation exchange resin and the anion exchange resin may be included in a volume ratio of 0.8:1.0 to 1.0:0.8.

[0034] According to one embodiment of the present invention, the resistivity of the water may be greater than 18 MΩ·cm.

[0035] According to one embodiment of the present invention, the gas may be a non-reactive gas or air.

[0036] According to one embodiment of the present invention, the non-reactive gas may be selected from nitrogen, helium, neon, argon, krypton, xenon and SF 6 One or more of the groups consisting of.

[0037] According to one embodiment of the present invention, the gas may be heated to 0.5 to 1.5 kgf / cm 2 pressure injection.

[0038] According to one embodiment of the present invention, the gas may be injected for more than 24 hours.

[0039] According to one embodiment of the present invention, the refining system may further include an intermediate storage tank provided at the rear end of the discharge pipe and a transfer pipe provided at the rear end of the intermediate storage tank and including a pump.

[0040] According to one embodiment of the present invention, the liquid level of the hydrogen peroxide solution in the intermediate storage tank may be greater than 30% of the internal height of the intermediate storage tank.

[0041] Effects of the Invention

[0042] The present invention can reduce the re-elution of ions during the purification process by preventing the layer separation of a mixed ion exchange resin formed by mixing a cation exchange resin and an anion exchange resin, thereby providing a method and a system for purifying hydrogen peroxide water having a purity that meets the requirements of the fine chemical field such as the semiconductor industry field.

[0043] In addition, the present invention can provide a method and system for purifying hydrogen peroxide water, wherein the risk of explosion is reduced by stably discharging the gas generated by the reaction between hydrogen peroxide and the ion exchange resin, and the process stability is improved by stably maintaining the liquid level of hydrogen peroxide water in the purification tower.

[0044] In addition, the present invention can increase the refining capacity and refining speed without excessively expanding the equipment, thereby providing a method and system for refining hydrogen peroxide water with improved productivity.

[0045] In addition, the present invention can prevent the catalytic reaction caused by drying of the ion exchange resin in the refining tower, thereby providing a method and a system for purifying hydrogen peroxide water in which unintended gas generation is reduced and ion exchange performance is further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 This is a diagram schematically showing the configuration of a hydrogen peroxide water purification system according to the first embodiment of the present invention.

[0047] Figure 2 This is a diagram schematically showing the configuration of a hydrogen peroxide water purification system according to a second embodiment of the present invention.

[0048] Figure 3 This is a diagram schematically showing the configuration of a hydrogen peroxide water purification system according to a third embodiment of the present invention.

[0049] Figure 4 This is a reference diagram for evaluating whether or not layer separation occurs in the mixed ion exchange resins used in Examples and Comparative Examples of the present invention.

[0050] Explanation of symbols

[0051] 10: Mixed ion exchange resin 20: Hydrogen peroxide water

[0052] 100: Refining tower 110: Hydrogen peroxide water injection pipe

[0053] 120: Gas injection pipe 200: Exhaust pipe

[0054] 300: Resin mixing tank 310: Gas injection pipe

[0055] 320: Resin transfer pipe 330: Ejector

[0056] 340: Fluid injection unit 400: Intermediate storage tank

[0057] 500: Pump 600: Transfer pipe DETAILED DESCRIPTION

[0058] The present invention relates to a method and system for purifying hydrogen peroxide water by passing hydrogen peroxide water through an ion exchange resin for purification, and to a method and system for purifying hydrogen peroxide water that satisfies the purity required in the field of fine chemicals and has improved process stability and productivity.

[0059] More specifically, the present invention relates to a method for purifying hydrogen peroxide water, comprising: (a) injecting gas into a mixture of a cation exchange resin, an anion exchange resin and water and bubbling the mixture to produce a mixed ion exchange resin; (b) passing the hydrogen peroxide water through the mixed ion exchange resin; and (c) discharging the hydrogen peroxide water that has passed through the mixed ion exchange resin.

[0060] The present invention also relates to a hydrogen peroxide water purification system, comprising a purification tower equipped with a gas injection pipe and a discharge pipe provided at the rear end of the purification tower, wherein after a mixture of a cation exchange resin, an anion exchange resin and water is fed into the purification tower, a gas is injected and bubbled through the gas injection pipe to produce a mixed ion exchange resin, and then hydrogen peroxide water is fed into the purification tower to pass through the mixed ion exchange resin.

[0061] In addition, the present invention relates to a hydrogen peroxide water purification system, comprising a resin mixing tank having a gas injection pipe and a resin transfer pipe, a refining tower provided at the rear end of the resin mixing tank, and a discharge pipe provided at the rear end of the refining tower, wherein a mixture of a cation exchange resin, an anion exchange resin, and water is introduced into the resin mixing tank, and then a gas is injected and bubbled through the gas injection pipe to produce a mixed ion exchange resin, the produced mixed ion exchange resin is injected into the refining tower through the resin transfer pipe, and hydrogen peroxide water is introduced into the refining tower so as to pass through the mixed ion exchange resin.

[0062] The method for purifying hydrogen peroxide water of the present invention is a method for removing impurities from hydrogen peroxide water synthesized by oneself or purchased from a supplier to obtain hydrogen peroxide water of higher purity.

[0063] The hydrogen peroxide water purification system of the present invention refers to the structure of a purification device for removing impurities from hydrogen peroxide water synthesized by oneself or purchased from a supplier to obtain hydrogen peroxide water of higher purity and its operation method.

[0064] Before being purified by the purification method or purification system of the present invention, the hydrogen peroxide water may contain undesirable amounts of contaminants and impurities. After being purified by the purification method or purification system of the present invention, a large amount of contaminants and impurities can be removed from the hydrogen peroxide water.

[0065] Hydrogen peroxide water before being purified by the purification method or purification system of the present invention is also referred to as "unpurified hydrogen peroxide water". Hydrogen peroxide water after being purified by the purification method or purification system of the present invention is also referred to as "purified hydrogen peroxide water". The above-mentioned "purified hydrogen peroxide water" may contain impurities limited to a predetermined range. In particular, the sodium ion of the purified hydrogen peroxide water used in the semiconductor process is preferably 10 ppt or less. The hydrogen peroxide water purified by the purification method or purification system of the present invention may contain sodium ions of 10 ppt or less.

[0066] Hereinafter, the embodiments of the present invention will be described in more detail with reference to the accompanying drawings. However, the following drawings attached to this specification are illustrations of preferred embodiments of the present invention, which serve to make the technical concept of the present invention and the above-mentioned invention contents more understandable, and therefore the present invention should not be interpreted only in accordance with the matters recorded in these drawings.

[0067] In this specification, unless otherwise specified in the context, a singular form also includes a plural form. Throughout the specification, the same reference numerals refer to the same constituent elements.

[0068] The terms “comprising…”, “including…”, “having…”, “having…”, “having…” and / or “having…” used in this specification are used in a sense that does not exclude the existence or addition of one or more other components, steps, actions and / or devices other than the mentioned components, steps, actions and / or devices.

[0069] As shown in the drawings, spatially relative terms such as "below", "lower (end, part)", "above", "upper (end, part)", etc. may be used to easily describe the relationship between one component and other components. Spatially relative terms should be understood as terms that include different directions from each other when used or operated in addition to the directions shown in the drawings.

[0070] The term “connect” as used in this specification is used to include both indirect connection and direct connection of a plurality of components.

[0071] In this specification, "ppb" means "parts per billion" and "ppt" means "parts per trillion".

[0072] <Hydrogen Peroxide Purification System>

[0073] Figures 1 to 3 It is a diagram schematically showing the configuration of a hydrogen peroxide water purification system according to first to third embodiments of the present invention.

[0074] Reference Figure 1 The hydrogen peroxide water purification system of the first embodiment of the present invention includes a purification tower 100 having a gas injection pipe 120 and a discharge pipe 200 provided at the rear end of the purification tower 100. Unpurified hydrogen peroxide water is introduced into the purification tower 100 through the hydrogen peroxide water introduction pipe 110, and is purified by the mixed ion exchange resin 10. The purified hydrogen peroxide water is discharged through the discharge pipe 200.

[0075] Unrefined hydrogen peroxide water contains a variety of impurities. Generally speaking, a cation exchange resin is used to remove cationic impurities, and an anion exchange resin is used to remove anionic impurities. In addition, in order to improve the process efficiency by removing cationic and anionic impurities at the same time, a mixed ion exchange resin formed by mixing a cation exchange resin and an anion exchange resin can be used. However, since the specific gravities of the cation exchange resin and the anion exchange resin are different from each other, it is difficult to prevent layer separation after mixing by the usual stirring method in the past. In this way, when the layer separation of the mixed ion exchange resin occurs, there is a problem that ions are re-dissolved in the resin and the removal performance of dissociative impurities is reduced.

[0076] The purification system of hydrogen peroxide water of the present invention is characterized in that the mixed ion exchange resin is manufactured by bubbling to prevent the layer separation of the mixed ion exchange resin. More specifically, after a mixture of a cation exchange resin, an anion exchange resin and water is put into the purification tower 100, a gas is injected through the gas injection pipe 120 and bubbling is performed to manufacture the mixed ion exchange resin 10.

[0077] In this way, the mixed ion exchange resin 10 is manufactured by fully mixing the cation exchange resin and the anion exchange resin by bubbling, so that the hydrogen peroxide water purification system of the present invention can prevent the layer separation of the mixed ion exchange resin during the purification process and reduce the re-elution of ions in the resin, thereby obtaining high-purity hydrogen peroxide water that meets the purity required in the field of fine chemicals.

[0078] When manufacturing the mixed ion exchange resin 10, a mixture of a cation exchange resin, an anion exchange resin and water is used. In this case, the volume of water (V W ) and the total volume of the cation exchange resin and the anion exchange resin (V R More specifically, in the mixture of the cation exchange resin, the anion exchange resin and water, the volume of water (V W ) and the total volume of the cation exchange resin and the anion exchange resin (V R ) ratio (V W / V R ) may be 0.1 to 0.3, preferably 0.1 to 0.2. The volume of water in the above mixture (V W ) and the total volume of the resin (V R ) ratio (V W / V R ) is less than 0.1, the problem that the entire amount of cation exchange resin and anion exchange resin cannot be completely mixed may occur, and when it is greater than 0.3, the mixed ion exchange resin may be separated into layers again during the refining process.

[0079] The cation exchange resin is not particularly limited as long as it can remove cationic impurities in hydrogen peroxide water, and may be one or more selected from the group consisting of strongly acidic cation exchange resins mainly composed of polystyrene and having a sulfonic acid group.

[0080] The anion exchange resin is not particularly limited as long as it can remove anionic impurities in hydrogen peroxide water, and may be one or more selected from the group consisting of strongly basic anion exchange resins having a quaternary ammonium group on a styrene skeleton.

[0081] The cation exchange resin and the anion exchange resin may be contained in a volume ratio of 0.8:1.0 to 1.0:0.8. When the volume ratio is satisfied, it is advantageous in that impurities generated in the respective ion exchange resins can be effectively purified from each other, which is preferred.

[0082] Pure water may be used as the water used in the production of the mixed ion exchange resin. However, water having a resistivity of 18 MΩ·cm or more is preferably used in order to prevent a decrease in the ion exchange capacity of the ion exchange resin.

[0083] The gas injected during the manufacture of the mixed ion exchange resin may be a non-reactive gas or air. The non-reactive gas may be selected from nitrogen, helium, neon, argon, krypton, xenon and SF 6Preferably, nitrogen can be used as one or more of the group consisting of. In addition, the gas may be a gas that has passed through a filter device to prevent impurities from being mixed in, and the filter device may be a filter having a filtration level of 0.001 to 0.01 um.

[0084] When manufacturing the mixed ion exchange resin, the gas injected may be 0.5 to 1.5 kgf / cm 2 The pressure injection is preferably 0.8 to 1.2 kgf / cm 2 When the gas is injected within the above pressure range, it is preferred because it has the advantages of ensuring physical stability during mixing and ensuring stable mixing to prevent layer separation of the mixed ion exchange resin.

[0085] The gas injected when manufacturing the mixed ion exchange resin can be injected for more than 24 hours, preferably for more than 36 hours, and more preferably for more than 48 hours. When the gas is injected within the above time range, the ion exchange resin can be completely mixed and the layer separation can be more effectively prevented, so it is preferred. The upper limit of the gas injection time is not particularly limited, but from the perspective of process time versus mixing efficiency, it can be less than 150 hours, preferably less than 120 hours.

[0086] Figure 2 1 and 2. A schematic diagram of a system for purifying hydrogen peroxide solution according to a second embodiment of the present invention is shown below. Figure 2 The hydrogen peroxide water purification system shown is Figure 1 The hydrogen peroxide water purification system of the first embodiment shown in the figure further comprises a resin mixing tank 300, Figure 1 The description of the hydrogen peroxide water purification system described in the same way can also be applied to Figure 2 In the hydrogen peroxide water purification system shown, detailed description of substantially the same or similar structures and compositions will be omitted.

[0087] The hydrogen peroxide water purification system of the second embodiment of the present invention may include a resin mixing tank 300 having a gas injection pipe 310 and a resin transfer pipe 320 , a purification tower 100 disposed at the rear end of the resin mixing tank 300 , and a discharge pipe 200 disposed at the rear end of the purification tower 100 .

[0088] The feature of the refining system of hydrogen peroxide water of the second embodiment of the present invention is that after the mixed ion exchange resin 10 is manufactured in the resin mixing tank 300, it is fed into the refining tower 100 through the resin transfer pipe 320. The mixed ion exchange resin used in the refining of hydrogen peroxide water has a predetermined ion exchange equivalent, and therefore must be replaced after a certain period of refining process. At this time, when the mixed ion exchange resin is manufactured in a separate resin mixing tank 300 and fed into the refining tower 100, there is an advantage that the refining tower 100 can be kept in operation during the manufacturing of the mixed ion exchange resin, thereby improving the overall process efficiency.

[0089] The hydrogen peroxide water purification system of the second embodiment of the present invention can prepare the mixed ion exchange resin 10 by injecting a mixture of a cation exchange resin, anion exchange resin and water into the resin mixing tank 300 and then injecting gas through the gas injection pipe 310 for bubbling.

[0090] The mixed ion exchange resin 10 manufactured as described above is injected into the refining tower 100 through the resin transfer piping 320. For example, the mixed ion exchange resin 10 can be put into the refining tower 100 through the resin transfer piping 320 equipped with an ejector 330, but it is not limited thereto. More specifically, the ejector 330 is arranged on the resin transfer piping 320, and the ejector 330 is arranged so that one end with a small diameter (hereinafter also referred to as the "front end") faces the resin mixing tank 300, and the other end with a large diameter (hereinafter also referred to as the "rear end") faces the refining tower 100. In addition, the front end of the ejector 330 is connected to a fluid injection part 340. When the fluid is injected through the fluid injection part 340, since the fluid flows in the narrow passage with a small diameter at the front end of the ejector 330, the flow velocity increases at the front end of the ejector 330 and the pressure decreases. As a result, a pressure difference is generated between the front end of the ejector 330 and the inside of the resin mixing tank 300, and the mixed ion exchange resin 10 in the resin mixing tank 300 is lifted toward the resin transfer pipe 320 where the ejector 330 is located, and this is used as a thrust to inject the mixed ion exchange resin 10 into the refining tower 100.

[0091] Pure water may be used as the fluid injected through the fluid injection part 340 . In order to prevent the ion exchange capacity of the ion exchange resin from being reduced, it is preferable to use water having a resistivity of 18 MΩ·cm or more.

[0092] After the mixed ion exchange resin 10 manufactured in the resin mixing tank 300 is fed into the refining tower 100, unpurified hydrogen peroxide water is fed into the refining tower 100 through the hydrogen peroxide water feeding pipe 110. The unpurified hydrogen peroxide water injected is purified by passing through the mixed ion exchange resin 10, and the purified hydrogen peroxide water is discharged through the discharge pipe 200.

[0093] Figure 3 This is a diagram schematically showing the configuration of a hydrogen peroxide water purification system according to a third embodiment of the present invention. Figure 3 The hydrogen peroxide water purification system shown is Figure 2 The hydrogen peroxide water purification system of the second embodiment shown in the figure further comprises an intermediate storage tank 400, a pump 500 and a transfer pipe 600. Figure 1 and Figure 2 The description of the hydrogen peroxide water purification system described in the same way can also be applied to Figure 3 The detailed description of the substantially same or similar structure and composition will be omitted.

[0094] The hydrogen peroxide water purification system of the third embodiment of the present invention may include a resin mixing tank 300 having a gas injection pipe 310 and a resin transfer pipe 320, a refining tower 100 disposed at the rear end of the resin mixing tank 300, a discharge pipe 200 disposed at the rear end of the refining tower 100, an intermediate storage tank 400 disposed at the rear end of the discharge pipe 200, and a transfer pipe 600 disposed at the rear end of the intermediate storage tank 400.

[0095] The refining tower 100 contains a mixed ion exchange resin 10 inside, and non-purified hydrogen peroxide water is fed through a hydrogen peroxide water feeding pipe 110. The non-purified hydrogen peroxide water fed is purified while passing from the upper part to the lower part of the mixed ion exchange resin 10, and the purified hydrogen peroxide water is discharged through a discharge pipe 200 at the lower end of the refining tower 100. The discharged purified hydrogen peroxide water is temporarily stored in an intermediate storage tank 400, and is transferred to a subsequent process or a final storage tank through a transfer pipe 600 provided at the rear end of the intermediate storage tank 400.

[0096] Considering the control of gas generated in the refining tower 100 and the refining efficiency of hydrogen peroxide solution, the mixed ion exchange resin 10 may be filled to 30 to 90% of the internal height of the refining tower 100, preferably 30 to 80%, and more preferably 30 to 70%.

[0097] At this time, the liquid level of the hydrogen peroxide solution 20 in the refining tower 100 is preferably maintained above the height of the mixed ion exchange resin 10 to prevent a portion of the mixed ion exchange resin 10 in the refining tower 100 from being exposed and dried due to not being immersed in the hydrogen peroxide solution 20 .

[0098] The liquid level of the hydrogen peroxide solution in the intermediate storage tank 400 is preferably 30% or more of the internal height of the intermediate storage tank 400. If this is satisfied, it is advantageously possible to prevent the pump 500 described later from running dry due to a drop in the liquid level of the hydrogen peroxide solution.

[0099] The hydrogen peroxide water purification system of the present invention may further include a pump 500 provided at the rear end of the intermediate storage tank 400 to provide thrust to the transfer pipe 600 .

[0100] If the pump 500 is disposed at the front end of the intermediate storage tank 400, i.e., the rear end of the refining tower 100, there will be a limitation in increasing the transfer thrust due to the outflow of the mixed ion exchange resin 10 in the refining tower 100, and it is difficult to provide sufficient transfer thrust. Therefore, the refining system of hydrogen peroxide water of the present invention has the advantages of solving the outflow problem of the mixed ion exchange resin 10 and providing sufficient transfer thrust to the transfer pipe 600 by disposing the pump 500 at the rear end of the intermediate storage tank 400.

[0101] The hydrogen peroxide water purification system of the present invention may be provided with the overall configuration of the purification system described above in a single unit or in a plurality of units. When provided with a plurality of units, the purity of the purified hydrogen peroxide water can be further improved by repeatedly performing the hydrogen peroxide water purification step.

[0102] <Method for Purifying Hydrogen Peroxide Water>

[0103] The method for purifying hydrogen peroxide water of the present invention may include: (a) a step of injecting gas into a mixture of a cation exchange resin, an anion exchange resin and water and bubbling to produce a mixed ion exchange resin; (b) a step of passing hydrogen peroxide water through the mixed ion exchange resin; and (c) a step of discharging the hydrogen peroxide water that has passed through the mixed ion exchange resin. In addition, after the above step (a) and before the above step (b), it may further include a step of (a-2) injecting the above-produced mixed ion exchange resin into a refining tower; after the above step (c), it may further include: (d) a step of transferring the hydrogen peroxide water discharged in the above step (c) to an intermediate storage tank; and (e) a step of transferring the hydrogen peroxide water in the above intermediate storage tank to a subsequent process or a final storage tank through a transfer pipe equipped with a pump.

[0104] The method for purifying hydrogen peroxide water of the present invention can produce hydrogen peroxide water by utilizing the above-mentioned system for purifying hydrogen peroxide water, and the contents of the above-mentioned <system for purifying hydrogen peroxide water> can be applied without limitation.

[0105] (a) Steps for producing mixed ion exchange resin

[0106] The method for purifying hydrogen peroxide water of the present invention comprises the step of injecting and bubbling a gas into a mixture of a cation exchange resin, an anion exchange resin and water to produce a mixed ion exchange resin.

[0107] As described above, in order to remove various impurities contained in unpurified hydrogen peroxide water, a mixed ion exchange resin in which a cation exchange resin and an anion exchange resin are mixed can be used. However, there is a problem that it is difficult to prevent layer separation after mixing by conventional stirring.

[0108] Therefore, the method for purifying hydrogen peroxide water of the present invention is characterized in that a mixed ion exchange resin is produced by bubbling to prevent layer separation of the mixed ion exchange resin. In this way, the mixed ion exchange resin is produced by fully mixing the cation exchange resin and the anion exchange resin by bubbling, so that the layer separation of the mixed ion exchange resin can be prevented during the purification process, and the re-elution of ions in the resin can be reduced, thereby obtaining high-purity hydrogen peroxide water that meets the purity required in the field of fine chemicals.

[0109] When preparing the above mixed ion exchange resin, the volume of water (V W ) and the total volume of the cation exchange resin and the anion exchange resin (V R More specifically, in the mixture of the cation exchange resin, the anion exchange resin and water, the volume of water (V W ) and the total volume of the cation exchange resin and the anion exchange resin (V R ) ratio (V W / V R ) may be 0.1 to 0.3, preferably 0.1 to 0.2. The volume of water in the above mixture (V W ) and the total volume of the resin (V R ) ratio (V W / V R ) is less than 0.1, the problem that the entire amount of cation exchange resin and anion exchange resin cannot be completely mixed may occur, and when it is greater than 0.3, the mixed ion exchange resin may be separated into layers again during the refining process.

[0110] The cation exchange resin is not particularly limited as long as it can remove cationic impurities in hydrogen peroxide water, and may be one or more selected from the group consisting of strongly acidic cation exchange resins mainly composed of polystyrene and having a sulfonic acid group.

[0111] The anion exchange resin is not particularly limited as long as it can remove anionic impurities in hydrogen peroxide water, and may be one or more selected from the group consisting of strongly basic anion exchange resins having a quaternary ammonium group on a styrene skeleton.

[0112] The cation exchange resin and the anion exchange resin may be contained in a volume ratio of 0.8:1.0 to 1.0:0.8. When the volume ratio is satisfied, it is advantageous in that impurities generated in the respective ion exchange resins can be effectively purified from each other, which is preferred.

[0113] Pure water may be used as the water used in the production of the mixed ion exchange resin. However, water having a resistivity of 18 MΩ·cm or more is preferably used in order to prevent a decrease in the ion exchange capacity of the ion exchange resin.

[0114] The gas injected during the manufacture of the mixed ion exchange resin may be a non-reactive gas or air. The non-reactive gas may be selected from nitrogen, helium, neon, argon, krypton, xenon and SF 6 Preferably, nitrogen can be used as one or more of the group consisting of. In addition, the gas may be a gas that has passed through a filter device to prevent impurities from being mixed in, and the filter device may be a filter having a filtration level of 0.001 to 0.01 um.

[0115] When manufacturing the mixed ion exchange resin, the gas injected may be 0.5 to 1.5 kgf / cm 2 The pressure injection is preferably 0.8 to 1.2 kgf / cm 2 When the gas is injected within the above pressure range, it is preferred because it has the advantages of ensuring physical stability during mixing and ensuring stable mixing to prevent layer separation of the mixed ion exchange resin.

[0116] The gas injected when manufacturing the mixed ion exchange resin can be injected for more than 24 hours, preferably for more than 36 hours, and more preferably for more than 48 hours. When the gas is injected within the above time range, the ion exchange resin can be completely mixed and the layer separation can be more effectively prevented, so it is preferred. The upper limit of the gas injection time is not particularly limited, but from the perspective of process time versus mixing efficiency, it can be less than 150 hours, preferably less than 120 hours.

[0117] The production of the mixed ion exchange resin can be carried out in the purification tower 100. In this case, it can be directly used for purification of unpurified hydrogen peroxide water.

[0118] In addition, the manufacture of the mixed ion exchange resin can be implemented in a separate resin mixing tank 300. In this case, the step of injecting the mixed ion exchange resin manufactured above into the refining tower 100 can be further included, and then it can be used for the refining of non-refined hydrogen peroxide water. Since the mixed ion exchange resin used in the refining of hydrogen peroxide water has a predetermined ion exchange equivalent, it must be replaced after a certain period of refining process. In this case, when the mixed ion exchange resin is manufactured in a separate resin mixing tank 300 and is fed into the refining tower 100, it has the advantage of being able to keep the refining tower 100 in operation during the manufacture of the mixed ion exchange resin, thereby improving the overall process efficiency.

[0119] Considering the control of gas generated in the refining tower 100 and the refining efficiency of hydrogen peroxide solution, the mixed ion exchange resin 10 may be filled to 30 to 90% of the internal height of the refining tower 100, preferably 30 to 80%, and more preferably 30 to 70%.

[0120] (b) Steps for carrying out purification

[0121] The method for purifying hydrogen peroxide water of the present invention comprises the steps of supplying unpurified hydrogen peroxide water to a purification tower 100 including a mixed ion exchange resin 10, and passing the unpurified hydrogen peroxide through the mixed ion exchange resin.

[0122] The unpurified hydrogen peroxide solution can be purified while passing from the upper part to the lower part of the mixed ion exchange resin 10, or while passing from the lower part to the upper part of the mixed ion exchange resin 10, and preferably, can be purified while moving from the upper part to the lower part of the mixed ion exchange resin 10. Since the hydrogen peroxide solution passes from the upper part to the lower part of the mixed ion exchange resin 10 in the refining tower 100, the concern that the ion exchange efficiency of the mixed ion exchange resin 10 is reduced due to the floating of the mixed ion exchange resin 10 can be prevented, and the refining capacity and refining speed of the hydrogen peroxide solution can be sufficiently increased without excessively enlarging the refining tower.

[0123] The amount of hydrogen peroxide solution supplied from the upper portion of the mixed ion exchange resin 10 and the amount of hydrogen peroxide solution discharged from the lower portion of the mixed ion exchange resin 10 are adjusted so that the mixed ion exchange resin 10 can be completely immersed in the hydrogen peroxide solution 20. This can be adjusted in a manner to stably maintain the liquid level of the hydrogen peroxide solution 20 through steps (c) to (e) described later.

[0124] At this time, the liquid level of the hydrogen peroxide solution 20 in the refining tower 100 is preferably maintained above the height of the mixed ion exchange resin 10 to prevent a portion of the mixed ion exchange resin 10 in the refining tower 100 from being exposed and dried due to not being immersed in the hydrogen peroxide solution 20 .

[0125] In this way, by preventing a portion of the mixed ion exchange resin 10 from being exposed and dried due to not being immersed in the hydrogen peroxide solution 20, the generation of gas can be minimized during the hydrogen peroxide solution purification process, and the risk of explosion in the process due to gas generation can be prevented without increasing the equipment. In addition, the generation of impurities caused by gas can be minimized to improve the purification efficiency.

[0126] The method for purifying hydrogen peroxide water of the present invention may repeatedly implement the above step (b). In this case, the mixed ion exchange resins 10 contained in each purification tower 100 may be of different types or of the same type.

[0127] (c) Step of discharging hydrogen peroxide solution

[0128] The method for purifying hydrogen peroxide water of the present invention includes the step of discharging the hydrogen peroxide water having passed through the mixed ion exchange resin.

[0129] The purified hydrogen peroxide solution having passed through the mixed ion exchange resin 10 in the purification tower 100 may be discharged through the discharge pipe 200 , and the discharged purified hydrogen peroxide solution may be transferred to a subsequent process or a final storage tank.

[0130] (d) Step of transferring to an intermediate storage tank

[0131] The method for purifying hydrogen peroxide water of the present invention may further include the step of transferring the hydrogen peroxide water discharged in the above step (c) to an intermediate storage tank 400 .

[0132] The liquid level of the hydrogen peroxide solution in the intermediate storage tank 400 may be greater than 30% of the internal height of the intermediate storage tank 400. When this is satisfied, it has the advantage of preventing the pump 500 described later from running idle due to the drop in the liquid level of the hydrogen peroxide solution.

[0133] (e) Steps of moving via transfer pipe

[0134] The method for purifying hydrogen peroxide solution of the present invention may further include the step of transferring the hydrogen peroxide solution in the intermediate storage tank 400 to a subsequent process or a final storage tank via a transfer pipe 600 having a pump 500 . In the transfer step, the pump 500 may provide a transfer thrust.

[0135] The transfer thrust provided by the pump 500 is preferably adjusted to a constant strength so as to maintain the liquid level of the intermediate storage tank 400 in the step (d) above, thereby being able to constantly adjust the flow rate transferred through the transfer pipe 600 .

[0136] In this way, by stably maintaining the liquid level of the hydrogen peroxide solution in the intermediate storage tank 400 , the liquid level of the hydrogen peroxide solution in the refining tower 100 can also be stably maintained.

[0137] The method for purifying hydrogen peroxide water of the present invention can further improve the purity of the purified hydrogen peroxide water by repeatedly performing all the steps for purifying hydrogen peroxide water described above.

[0138] The following are specific examples of the present invention. However, the present invention is not limited to the following examples, and can be implemented in various different ways. The examples are only provided to complete the description of the present invention and to enable a person skilled in the art to fully understand the scope of the invention. The present invention is only defined by the scope of the claims.

[0139] <Examples and Comparative Examples>

[0140] Example 1

[0141] In a refining tower with an inner diameter of 700 mm and an inner height of 3600 mm, a mixture of 275 L of cation exchange resin (functional group: sulfonic acid group; ion exchange capacity: 2.0 eq / L; effective acidity: pH 0-14), 275 L of anion exchange resin (functional group: quaternary ammonium group; ion exchange capacity: 1.0 eq / L; effective acidity: pH 1-14) and 55 L of water (resistivity 18.2 MΩ·cm) was charged and the mixture was heated at 1.0 kgf / cm2 through a gas injection valve connected to the lower end of the refining tower. 2 The mixed ion exchange resin was produced by injecting air that had passed through a filter (filtration grade 0.05 um) for 24 hours at a pressure of 1000 μm and bubbling. The height of the mixed ion exchange resin produced above was 40% (1440 mm) of the internal height of the refining tower. Then, unrefined hydrogen peroxide water (31%, impurity level 10 ppb) was introduced through the introduction pipe at the top of the refining tower to pass through the mixed ion exchange resin, and the temperature was maintained below 15°C.

[0142] The purified hydrogen peroxide solution (31%) that had passed through the mixed ion exchange resin was discharged at a flow rate of 1650 L / hr through a discharge pipe connected to the lower end of the purification tower.

[0143] Example 2

[0144] The unpurified hydrogen peroxide solution was purified by the same method as in Example 1 except that a mixture of 275 L of cation exchange resin, 275 L of anion exchange resin, and 110 L of water was used when producing the mixed ion exchange resin.

[0145] Example 3

[0146] The unpurified hydrogen peroxide solution was purified by the same method as in Example 1 except that a mixture of 275 L of cation exchange resin, 275 L of anion exchange resin, and 165 L of water was used when producing the mixed ion exchange resin.

[0147] Example 4

[0148] The unpurified hydrogen peroxide solution was purified by the same method as in Example 1 except that a mixture of 275 L of cation exchange resin, 275 L of anion exchange resin, and 198 L of water was used when producing the mixed ion exchange resin.

[0149] Example 5

[0150] The unpurified hydrogen peroxide solution was purified by the same method as in Example 1 except that a mixture of 220 L of cation exchange resin, 275 L of anion exchange resin, and 79 L of water was used when producing the mixed ion exchange resin.

[0151] Example 6

[0152] The unpurified hydrogen peroxide solution was purified by the same method as in Example 1 except that a mixture of 275 L of cation exchange resin, 220 L of anion exchange resin, and 79 L of water was used when producing the mixed ion exchange resin.

[0153] Example 7

[0154] The unpurified hydrogen peroxide solution was purified by the same method as in Example 1 except that a mixture of 165 L of cation exchange resin, 275 L of anion exchange resin, and 70 L of water was used when producing the mixed ion exchange resin.

[0155] Example 8

[0156] The unpurified hydrogen peroxide solution was purified by the same method as in Example 1 except that a mixture of 275 L of cation exchange resin, 165 L of anion exchange resin, and 70 L of water was used when producing the mixed ion exchange resin.

[0157] Example 9

[0158] The unpurified hydrogen peroxide solution was purified by the same method as in Example 2 except that air was injected for 10 hours during the production of the mixed ion exchange resin.

[0159] Example 10

[0160] The unpurified hydrogen peroxide solution was purified by the same method as in Example 2 except that air was injected for 48 hours during the production of the mixed ion exchange resin.

[0161] Embodiment 11

[0162] The unpurified hydrogen peroxide solution was purified by the same method as in Example 2 except that the mixed ion exchange resin was produced in a separate resin mixing tank and then charged into the purification tower.

[0163] Example 12

[0164] The unpurified hydrogen peroxide water was purified by the same method as in Example 2, except that the hydrogen peroxide water discharged through the discharge pipe was transferred to an intermediate storage tank (inner diameter 1000 mm, inner height 1500 mm), and the hydrogen peroxide water temporarily stored in the intermediate storage tank was transferred to the final storage tank through a transfer pipe equipped with a pump. At this time, the height of the hydrogen peroxide water transferred to the intermediate storage tank was adjusted so as to be maintained at 50% of the inner height of the intermediate storage tank.

[0165] Comparative Example 1

[0166] The unpurified hydrogen peroxide solution was purified by the same method as in Example 1, except that mixing was performed by stirring without injecting air when producing the mixed ion exchange resin.

[0167] Experimental example

[0168] 1. Evaluation of layer separation of mixed ion exchange resins

[0169] Each mixed ion exchange resin produced in the above Examples and Comparative Examples was placed in a 50 L cylinder and visually observed to determine whether layer separation occurred after 1 hour and 14 days. Evaluation was performed based on the following evaluation criteria. The results are shown in Table 1 below.

[0170] <Layer Separation Evaluation Criteria>

[0171] ○: No layer separation occurred (refer to Figure 4 "○"

[0172] ×: Layer separation occurred (refer to Figure 4 "×"

[0173] 2. Purity evaluation of purified hydrogen peroxide water

[0174] The sodium ion concentration of the hydrogen peroxide water purified by the above-mentioned examples and comparative examples was measured on a daily basis for 2 months using an inductively coupled plasma-mass spectrometer (ICP-MS; Agilent, 8900), and evaluated according to the following evaluation criteria. The results are shown in the following Table 1.

[0175] <Purity Evaluation Criteria for Purified Hydrogen Peroxide>

[0176] ◎: Average sodium ion concentration is below 0.005 ppb

[0177] ○: Average sodium ion concentration is greater than 0.005 ppb and less than 0.01 ppb

[0178] △: Average sodium ion concentration is greater than 0.01 ppb and less than 0.02 ppb

[0179] ×: Average sodium ion concentration greater than 0.02 ppb

[0180] 3. Evaluation of gas generation in the refining tower

[0181] A gas flow meter was installed on the top of the refining tower to measure the gas generation amount for one week. The gas generation amount was evaluated according to the following evaluation criteria. The results are shown in Table 1 below.

[0182] <Evaluation criteria for gas generation in refining tower>

[0183] ○: Gas generation is less than 7L / hr

[0184] △: Gas generation is 7L / hr or more and less than 10L / hr

[0185] ×: Gas generation is 10L / hr or more

[0186] [Table 1]

[0187]

Claims

1. A method for refining hydrogen peroxide solution, comprising: (a) a step of injecting and bubbling a gas into a mixture of a cation exchange resin, an anion exchange resin and water to produce a mixed ion exchange resin; (b) a step of passing hydrogen peroxide water through the mixed ion exchange resin; and (c) a step of discharging the hydrogen peroxide solution that has passed through the mixed ion exchange resin.

2. The method for purifying hydrogen peroxide water according to claim 1, wherein in step (a), the volume V of water is W The total volume V of the cation exchange resin and anion exchange resin R V W / V R It is 0.1 to 0.

3.

3. The method for purifying hydrogen peroxide water according to claim 1, wherein the step (a) is performed in a resin mixing tank. After the step (a) and before the step (b), the method further comprises the step of (a-2) injecting the produced mixed ion exchange resin into a refining tower.

4. The method for purifying hydrogen peroxide water according to claim 1, wherein in the step (a), the cation exchange resin and the anion exchange resin are contained in a volume ratio of 0.8:1.0 to 1.0:0.

8. 5 . The method for purifying hydrogen peroxide water according to claim 1 , wherein in the step (a), the resistivity of the water is 18 MΩ·cm or more. 6 . The method for purifying hydrogen peroxide water according to claim 1 , wherein in the step (a), the gas is a non-reactive gas or air.

7. The method for purifying hydrogen peroxide water according to claim 6, wherein the non-reactive gas is one or more selected from the group consisting of nitrogen, helium, neon, argon, krypton, xenon and SF6.

8. The method for purifying hydrogen peroxide water according to claim 1, wherein in the step (a), the gas is heated at a rate of 0.5 to 1.5 kgf / cm 2 pressure injection.

9. The method for purifying hydrogen peroxide water according to claim 1, wherein the step (a) is performed for more than 24 hours.

10. The method for purifying hydrogen peroxide water according to claim 1, further comprising, after step (c): (d) a step of transferring the hydrogen peroxide solution discharged in step (c) to an intermediate storage tank; as well as (e) A step of transferring the hydrogen peroxide solution in the intermediate storage tank to a subsequent step or a final storage tank via a transfer pipe equipped with a pump. 11 . The method for purifying hydrogen peroxide solution according to claim 10 , wherein the liquid level of the hydrogen peroxide solution in the intermediate storage tank is 30% or more of the internal height of the intermediate storage tank.

12. The method for purifying hydrogen peroxide water according to claim 10, wherein in the step (e), the pump provides the transfer thrust.

13. A system for refining hydrogen peroxide solution, comprising a refining tower having a gas injection pipe and a discharge pipe provided at the rear end of the refining tower, In the hydrogen peroxide water purification system, After a mixture of a cation exchange resin, an anion exchange resin and water is introduced into the refining tower, a gas is injected through the gas injection pipe for bubbling to produce a mixed ion exchange resin. Aqueous hydrogen peroxide is introduced into the refining tower to pass through the mixed ion exchange resin.

14. The hydrogen peroxide water purification system according to claim 13, wherein the volume V of water in the mixture is W The total volume V of the cation exchange resin and anion exchange resin R V W / V R It is 0.1 to 0.

3. 15 . The system for purifying hydrogen peroxide water according to claim 13 , wherein the cation exchange resin and the anion exchange resin are contained in a volume ratio of 0.8:1.0 to 1.0:0.

8. 16 . The system for purifying hydrogen peroxide water according to claim 13 , wherein the resistivity of the water is 18 MΩ·cm or more.

17. The hydrogen peroxide water purification system according to claim 13, wherein the gas is a non-reactive gas or air.

18. The system for purifying hydrogen peroxide solution according to claim 17, wherein the non-reactive gas is one or more selected from the group consisting of nitrogen, helium, neon, argon, krypton, xenon and SF6.

19. The hydrogen peroxide water purification system according to claim 13, wherein the gas has a flow rate of 0.5 to 1.5 kgf / cm 2 pressure injection.

20. The system for purifying hydrogen peroxide water according to claim 13, wherein the gas is injected for more than 24 hours.

21. The hydrogen peroxide water purification system according to claim 13, further comprising: an intermediate storage tank provided at the rear end of the discharge pipe; and A transfer pipe is provided at the rear end of the intermediate storage tank and includes a pump.

22. The system for purifying hydrogen peroxide solution according to claim 21, wherein the liquid level of the hydrogen peroxide solution in the intermediate storage tank is 30% or more of the internal height of the intermediate storage tank.

23. A hydrogen peroxide water purification system comprising a resin mixing tank having a gas injection pipe and a resin transfer pipe, a purification tower provided at the rear end of the resin mixing tank, and a discharge pipe provided at the rear end of the purification tower, In the hydrogen peroxide water purification system, After a mixture of a cation exchange resin, an anion exchange resin and water is placed in the resin mixing tank, gas is injected through the gas injection pipe for bubbling to produce a mixed ion exchange resin. The manufactured mixed ion exchange resin is injected into the refining tower through the resin transfer pipe, Aqueous hydrogen peroxide is fed into the refining tower so as to pass through the mixed ion exchange resin.

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