Method and device for purifying hydrogen peroxide water

Abstract

The present invention relates to a method and an apparatus for purifying hydrogen peroxide water, which can provide a part in which an ion exchange resin does not dry when purifying hydrogen peroxide water by using the ion exchange resin, so that the generated gas can be controlled without expanding equipment. And high-purity hydrogen peroxide water can be obtained by the method and the device for purifying the hydrogen peroxide water. The method for purifying hydrogen peroxide water is characterized by comprising: (a) a step in which hydrogen peroxide water is supplied to a purification tower containing an ion exchange resin and purified; and (b) a step for discharging hydrogen peroxide water through a discharge pipe connected to the lower end of the purification tower and including a liquid level holding pipe, in which the hydrogen peroxide water flows downward from above the ion exchange resin in step (a), and in which the hydrogen peroxide water flows downward from below the ion exchange resin in step (b), the hydrogen peroxide water flows downward from below the ion exchange resin in step (b). And the maximum height of the liquid level keeping pipe is more than the height of ion exchange resin in the refining tower.

Description

Technical Field

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

[0002] Generally speaking, hydrogen peroxide is easily soluble in water, ethanol, and ether. It partially dissociates hydrogen ions in aqueous solution and becomes weakly acidic. It also has strong oxidizing power, so it is used in many fields such as the bleaching process of paper and pulp, industrial oxidants, and wastewater treatment. In particular, hydrogen peroxide is used for cleaning semiconductor wafers and etching in the semiconductor and display manufacturing process. Since tiny dust or impurities on the wafer in the semiconductor manufacturing process can greatly affect the reliability of the semiconductor and become a cause of the decline in semiconductor yield, it is very important to use high-purity materials.

[0003] Therefore, in order to use hydrogen peroxide water in the field of precision chemicals such as the semiconductor industry, hydrogen peroxide water with very high purity is required.

[0004] As a method for reducing impurities in hydrogen peroxide water, a method using ion exchange resin or a method using reverse osmosis membrane has been proposed. However, the method using reverse osmosis membrane has a problem that as high-concentration hydrogen peroxide water continues to contact the reverse osmosis membrane, the reverse osmosis membrane deteriorates and the supporting capacity decreases.

[0005] When the above-mentioned ion exchange resin is used to purify hydrogen peroxide water, when hydrogen peroxide contacts the ion exchange resin, the hydrogen peroxide undergoes a decomposition reaction to generate heat or gas. Therefore, in order to smoothly discharge the generated gas, an upflow process is designed to make the hydrogen peroxide water flow from the bottom of the ion exchange resin to the top.

[0006] In the case of such an upflow process, the ion exchange resin will float upward (i.e., float), so it is necessary to expand the equipment such as the purification tower containing the ion exchange resin to improve productivity. However, there are limitations in expanding the equipment, so there are also limitations in improving the purification efficiency of hydrogen peroxide water.

[0007] Therefore, a downflow process is designed to make hydrogen peroxide water flow from the top to the bottom of the ion exchange resin, thereby developing a technology for improving the above-mentioned problem. However, in the above-mentioned downflow process, there is a concern that the ion exchange resin is not immersed in the hydrogen peroxide water but is exposed to the air. In this case, a dry area will appear in the ion exchange resin. Due to the contact between the dry ion exchange resin and the hydrogen peroxide water added, the generation of gas will increase rapidly, which may lead to an increase in the concentration of impurities.

[0008] Japanese Patent Publication No. 2006-077118 discloses a method for purifying hydrogen peroxide water that can reduce the concentration of impurities by providing a tower containing an ion exchange resin and adjusting the mixing ratio of cations and anions. However, there is still a problem that gas generation may increase due to exposure of the ion exchange resin to air.

[0009] Prior art literature

[0010] Patent Literature

[0011] Patent Document 1: Japanese Patent Publication No. 2006-077118 Summary of the invention

[0012] Issues to be solved

[0013] The present invention aims to provide a method and apparatus for purifying hydrogen peroxide water, which can constantly maintain the liquid level of hydrogen peroxide water in a purification tower when purifying hydrogen peroxide water using an ion exchange resin, and can stably discharge the gas generated during the purification of hydrogen peroxide water to improve process stability.

[0014] In addition, the present invention aims to provide a method and apparatus for purifying hydrogen peroxide water, which can increase the purification capacity and purification speed without excessively expanding the equipment, thereby improving productivity.

[0015] In addition, the present invention aims to provide a method and apparatus for purifying hydrogen peroxide water, which can reduce unintended gas generation and further improve ion exchange performance by preventing the ion exchange resin in the purification tower from drying and causing a mixed contact reaction.

[0016] In addition, the present invention intends to provide a method and apparatus for purifying hydrogen peroxide solution that can provide high-purity hydrogen peroxide solution.

[0017] 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.

[0018] Solution to the problem

[0019] In order to solve the above-mentioned problems, the present invention provides a method for purifying hydrogen peroxide solution, characterized in that it includes: (a) supplying hydrogen peroxide solution to a refining tower including an ion exchange resin to perform purification; and (b) discharging the hydrogen peroxide solution through a discharge pipe connected to the lower end of the refining tower and including a liquid level holding pipe, wherein in the above-mentioned step (a), the hydrogen peroxide solution flows downward from above the ion exchange resin, and in the above-mentioned step (b), the maximum height of the above-mentioned liquid level holding pipe is greater than the height of the ion exchange resin in the above-mentioned refining tower.

[0020] According to one embodiment of the present invention, the maximum height of the liquid level holding tube may be 110% or more, or 120% or more of the height of the ion exchange resin in the refining tower.

[0021] According to one embodiment of the present invention, the maximum height of the liquid level holding tube may be 140% or less or 130% or less of the height of the ion exchange resin in the refining tower.

[0022] According to one embodiment of the present invention, the ion exchange resin may be a mixed ion exchange resin formed by mixing a cation exchange resin and an anion exchange resin.

[0023] According to one embodiment of the present invention, after the above step (b), the method may further include: (c) a step of transferring the hydrogen peroxide water discharged in the above step (b) to an intermediate storage tank; and (d) a step of transferring the hydrogen peroxide water in the above intermediate storage tank to a subsequent process or a final storage tank via a transfer pipe equipped with a pump.

[0024] 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.

[0025] According to one embodiment of the present invention, in the step (d), the pump may provide the transfer thrust.

[0026] According to one embodiment of the present invention, the purity of the purified hydrogen peroxide solution can be further improved by repeating the entire process including the above steps (a) and (b).

[0027] The present invention also provides a hydrogen peroxide water purification device comprising a purification tower equipped with an ion exchange resin, and a discharge pipe connected to the lower end of the purification tower and equipped with a liquid level holding pipe, wherein the maximum height of the liquid level holding pipe is greater than the height of the ion exchange resin in the purification tower.

[0028] According to one embodiment of the present invention, the maximum height of the liquid level holding tube may be 110% or more, or 120% or more of the height of the ion exchange resin in the refining tower.

[0029] According to one embodiment of the present invention, the maximum height of the liquid level holding tube may be 140% or less or 130% or less of the height of the ion exchange resin in the refining tower.

[0030] According to one embodiment of the present invention, the ion exchange resin may be a mixed ion exchange resin formed by mixing a cation exchange resin and an anion exchange resin.

[0031] According to one embodiment of the present invention, the refining device may further include an intermediate storage tank connected to the discharge pipe.

[0032] According to one embodiment of the present invention, the rear end of the intermediate storage tank may be connected to a transfer pipe, and the transfer pipe may include a pump.

[0033] Effects of the Invention

[0034] According to the present invention, a method and apparatus for purifying hydrogen peroxide water can be provided, which can maintain the liquid level of hydrogen peroxide water in a purification tower constant when purifying hydrogen peroxide water using an ion exchange resin, and can stably discharge gas generated during purification of hydrogen peroxide water to improve process stability.

[0035] In addition, the present invention can provide a method and apparatus for purifying hydrogen peroxide solution that can increase the purification capacity and purification speed without excessively expanding the equipment, thereby improving productivity.

[0036] In addition, the present invention can provide a method and apparatus for purifying hydrogen peroxide water, which can reduce unexpected gas generation and further improve ion exchange performance by preventing the ion exchange resin in the purification tower from drying out and causing a catalytic reaction.

[0037] In addition, the present invention can provide a method and apparatus for purifying hydrogen peroxide water, which can obtain high-purity hydrogen peroxide water by minimizing the generation of impurities when purifying hydrogen peroxide water using an ion exchange resin. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a diagram schematically showing an apparatus for purifying hydrogen peroxide water and a method for producing hydrogen peroxide water using the apparatus according to an embodiment of the present invention.

[0039] Figure 2 This is a diagram schematically showing an apparatus for purifying hydrogen peroxide water and a method for producing hydrogen peroxide water using the same according to another embodiment of the present invention.

[0040] Explanation of symbols

[0041] 10: ion exchange resin 20: hydrogen peroxide water

[0042] 100: Refining tower 130: Input pipe

[0043] 200: discharge pipe 210: liquid level holding pipe

[0044] 300: Intermediate storage tank 400: Pump

[0045] 500: Transfer piping DETAILED DESCRIPTION

[0046] The present invention relates to a method and an apparatus for purifying hydrogen peroxide water by passing hydrogen peroxide water through an ion exchange resin for purification, and relates to a method and an apparatus for purifying hydrogen peroxide water that satisfies the purity required in the field of fine chemicals and improves process stability and productivity.

[0047] More specifically, the present invention provides a method for purifying hydrogen peroxide solution, characterized in that it includes: (a) supplying hydrogen peroxide solution to a refining tower including an ion exchange resin to perform purification; and (b) discharging the hydrogen peroxide solution through a discharge pipe connected to the lower end of the refining tower and including a liquid level holding pipe, wherein in the step (a), the hydrogen peroxide solution flows downward from above the ion exchange resin, and in the step (b), the maximum height of the liquid level holding pipe is greater than the height of the ion exchange resin in the refining tower.

[0048] The present invention also provides a hydrogen peroxide water purification device comprising a purification tower equipped with an ion exchange resin, and a discharge pipe connected to the lower end of the purification tower and equipped with a liquid level holding pipe, wherein the maximum height of the liquid level holding pipe is greater than the height of the ion exchange resin in the purification tower.

[0049] 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.

[0050] Before the purification method of the present invention is implemented, the hydrogen peroxide water may contain undesirable amounts of pollutants and impurities. After purification by the purification method of the present invention, a large amount of pollutants and impurities can be removed from the hydrogen peroxide water.

[0051] Hydrogen peroxide water before being purified by the purification method or purification device 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 device 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.

[0052] In particular, the sodium ion content of the purified hydrogen peroxide solution used in semiconductor processes is preferably 10 ppt or less. The hydrogen peroxide solution purified by the purification method or purification device of the present invention may contain 10 ppt or less of sodium ions.

[0053] 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.

[0054] The terms used in this specification are intended to illustrate the embodiments and are not intended to limit the present invention. In this specification, unless otherwise specifically mentioned in the context, a singular form also includes a plural form.

[0055] 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 constituent elements, steps, actions and / or devices other than the mentioned constituent elements, steps, actions and / or devices. Throughout the specification, the same reference numerals refer to the same constituent elements.

[0056] 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.

[0057] The term “connect” as used in this specification is used to include both indirect connection and direct connection of a plurality of components.

[0058] In this specification, "ppb" means "parts per billion" and "ppt" means "parts per trillion".

[0059] <Hydrogen Peroxide Purification Device>

[0060] Figure 1 is a diagram schematically showing a hydrogen peroxide water purification device and a method for producing hydrogen peroxide water using the same according to one embodiment of the present invention. Figure 2 This is a diagram schematically showing an apparatus for purifying hydrogen peroxide water and a method for producing hydrogen peroxide water using the same according to another embodiment of the present invention.

[0061] Reference Figure 1The hydrogen peroxide water purification device of the present invention includes a purification tower 100 and a discharge pipe 200 for discharging the hydrogen peroxide water purified by the purification tower 100 .

[0062] The discharge pipe 200 is characterized in that it is connected to the lower end of the refining tower 100 so that the hydrogen peroxide solution purified in the refining tower 100 is discharged to the lower end of the refining tower 100 , and includes a liquid level holding pipe 210 .

[0063] The refining tower 100 may include an ion exchange resin 10 therein, and unrefined hydrogen peroxide water is fed in through a feed pipe 130. The unrefined hydrogen peroxide water fed in is purified while passing from the upper part to the lower part of the 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.

[0064] Considering the control of gas generated in the refining tower 100 and the refining efficiency of hydrogen peroxide solution, the 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%.

[0065] 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 ion exchange resin 10 to prevent a portion of the 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 .

[0066] To this end, the present invention may include a liquid level holding pipe 210 on the discharge pipe 200 , and the liquid level of the hydrogen peroxide solution 20 may be maintained above the level of the ion exchange resin 10 by the liquid level holding pipe 210 .

[0067] In the present invention, the above-mentioned liquid level maintaining tube 210 refers to a part of the discharge piping 200 including a U-shaped bent portion, and may have a shape bent in such a manner that the two ends of the liquid level maintaining tube face the same direction and the middle portion protrudes in a direction different from the above-mentioned two ends. The shape of the above-mentioned bent portion is not limited to the U-shape, and may include a U-shaped variant, a V-shaped variant, and a V-shaped variant.

[0068] In view of piping pressure loss, the diameter of the liquid level holding pipe 210 is preferably 50 to 100 mm, and in view of piping cost and pressure loss, the distance between the liquid level holding pipe 210 and the refining tower 100 is preferably within 20 m.

[0069] In addition, the liquid level maintaining pipe 210 is preferably made of the same material as that of the refining tower 100 .

[0070] The U-shaped curved portion faces upward rather than the ground, and its uppermost portion is the maximum height of the liquid level holding pipe 210. The purified hydrogen peroxide solution transferred through the liquid level holding pipe 210 passes through a section where it is transferred in the opposite direction to the action of gravity before passing through the U-shaped curved portion with the maximum height.

[0071] Therefore, when the liquid level of the hydrogen peroxide solution 20 in the refining tower 100 is higher than or equal to the maximum height of the liquid level holding tube 210, the purified hydrogen peroxide solution discharged from the refining tower 100 can pass through the liquid level holding tube 210. On the contrary, if the liquid level of the hydrogen peroxide solution 20 in the refining tower 100 is lower than the maximum height of the liquid level holding tube 210, the purified hydrogen peroxide solution discharged from the refining tower 100 cannot reach the maximum height of the liquid level holding tube 210 and cannot pass through the liquid level holding tube 210.

[0072] Therefore, when the maximum height of the liquid level holding tube 210 is higher than the height of the ion exchange resin 10 in the refining tower 100, the liquid level of the hydrogen peroxide solution 20 in the refining tower 100 can be maintained higher than the height of the ion exchange resin 10, thereby fundamentally preventing a portion of the ion exchange resin 10 in the refining tower 100 from being exposed and dried without being immersed in the hydrogen peroxide solution 20.

[0073] By maintaining the height of the hydrogen peroxide solution 20 in the purification tower 100 above the height of the ion exchange resin 10 by the liquid level holding tube 210, sufficient time for the hydrogen peroxide solution to pass through the ion exchange resin can be ensured, thereby improving the purification efficiency and the purity of the purified hydrogen peroxide solution.

[0074] Furthermore, the maximum height of the liquid level holding tube 210 may be 110% or more, preferably 120% or more, of the height of the ion exchange resin 10 in the refining tower 100. When the above numerical range is satisfied, there is an advantage that even if the liquid level of the hydrogen peroxide solution 20 in the refining tower 100 slightly shakes, the ion exchange resin can be fully immersed in the hydrogen peroxide solution, and thus even if the refining process is performed, no exposed part of the ion exchange resin will appear, thereby enabling more stable control of the generated gas.

[0075] In addition, the maximum height of the liquid level holding pipe 210 may be 140% or less, preferably 130% or less, of the height of the ion exchange resin 10 in the refining tower 100. When the above numerical range is satisfied, there are advantages that the resin layer will not be exposed even if the liquid level of the hydrogen peroxide solution in the refining tower is shaken, and sufficient space is ensured at the top of the refining tower, making it easy to control the gas generated in the refining tower.

[0076] The liquid level holding pipe 210 may have a symmetrical shape centered on the U-shaped curved portion as shown in the drawings, but is not limited thereto. If necessary, the heights of the left and right pipes may be formed to be different based on the U-shaped curved portion.

[0077] In the present invention, the ion exchange resin 10 contained in the refining tower 100 may be selected from cation exchange resin, anion exchange resin or mixed ion exchange resin, wherein, considering the purification efficiency of hydrogen peroxide water, a mixed ion exchange resin in which a cation exchange resin and anion exchange resin are mixed is preferably used.

[0078] 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.

[0079] 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.

[0080] 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, impurities generated in the ion exchange resins can be purified mutually, which is preferred.

[0081] Reference Figure 2 The hydrogen peroxide water purification device of the present invention may further include an intermediate storage tank 300. The intermediate storage tank 300 is connected to the discharge piping 200 connected to the lower end of the refining tower 100, so that the hydrogen peroxide water purified and discharged by the refining tower 100 can be collected in the intermediate storage tank 300, and the hydrogen peroxide water in the intermediate storage tank 300 can be transferred to the subsequent process or the final storage tank through the transfer piping 500.

[0082] The liquid level of the hydrogen peroxide solution in the intermediate storage tank 300 is preferably 30% or more of the internal height of the intermediate storage tank 300. When this is satisfied, it is advantageously possible to prevent the pump 400 described later from running idle due to a drop in the liquid level of the hydrogen peroxide solution.

[0083] The hydrogen peroxide water purification device of the present invention may further include a pump 400 provided at the rear end of the intermediate storage tank 300 to provide thrust to the transfer pipe 500 .

[0084] If the pump 400 is disposed at the front end of the intermediate storage tank 300, 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 ion exchange resin 10 in the refining tower 100, and it is difficult to provide a sufficient transfer thrust. Therefore, the refining system of hydrogen peroxide water of the present invention has the advantage of being able to solve the outflow problem of the ion exchange resin 10 and provide a sufficient transfer thrust to the transfer pipe 500 by disposing the pump 400 at the rear end of the intermediate storage tank 300.

[0085] The refining device for hydrogen peroxide water of the present invention can be configured as a single unit or multiple units to form the entire refining device including the above-mentioned structure. When configured as multiple units, the ion exchange resin 10 contained in the refining tower 100 can be the same resin as the ion exchange resin 10 used above, or can be a different type of resin.

[0086] When the hydrogen peroxide water purification apparatus of the present invention is installed in a plurality of units, the hydrogen peroxide water purification step can be fully performed, and the purity of the purified hydrogen peroxide water can be improved.

[0087] <Method for Purifying Hydrogen Peroxide Water>

[0088] The method for purifying hydrogen peroxide water of the present invention can purify hydrogen peroxide water using the above-mentioned hydrogen peroxide water purifying device, and specifically, can include: (a) supplying hydrogen peroxide water to a purifying tower including an ion exchange resin to purify the hydrogen peroxide water; and (b) discharging the hydrogen peroxide water through a discharge pipe connected to the lower end of the above-mentioned purifying tower and including a liquid level holding pipe, and after the above-mentioned step (b), can further include: (c) transferring the hydrogen peroxide water discharged in the above-mentioned step (b) to an intermediate storage tank; and (d) transferring the hydrogen peroxide water in the above-mentioned intermediate storage tank to a subsequent process or a final storage tank through a transfer pipe equipped with a pump.

[0089] The method for purifying hydrogen peroxide water of the present invention may be a method of purifying hydrogen peroxide water using the above-mentioned apparatus for purifying hydrogen peroxide water, and the contents of the above-mentioned <Apparatus for purifying hydrogen peroxide water> may be applied without limitation.

[0090] (a) Refining steps

[0091] The method for purifying hydrogen peroxide water of the present invention includes a step of supplying hydrogen peroxide water to a purification tower 100 including an ion exchange resin 10 to purify the water.

[0092] The hydrogen peroxide solution is purified by passing through the ion exchange resin 10 in the purification tower 100 . Specifically, the hydrogen peroxide solution can be purified while passing from the upper part to the lower part of the ion exchange resin 10 .

[0093] For this purpose, the hydrogen peroxide solution may be sprayed on the upper portion of the ion exchange resin 10 in the refining tower 100 so as to flow downward through the ion exchange resin 10 and be discharged in the subsequent step (b).

[0094] By allowing the hydrogen peroxide solution to flow from the upper part to the lower part of the ion exchange resin 10 in the refining tower 100, it is possible to prevent the ion exchange efficiency of the ion exchange resin 10 from being reduced due to the floating of the ion exchange resin 10, and even without excessively increasing the size of the refining tower, the refining capacity and refining speed of the hydrogen peroxide solution can be sufficiently increased.

[0095] The amount of hydrogen peroxide solution supplied from the upper portion of the ion exchange resin 10 and the amount of hydrogen peroxide solution discharged from the lower portion of the ion exchange resin 10 are adjusted so that the ion exchange resin 10 can be completely immersed in the hydrogen peroxide solution 20. This can be adjusted by stably maintaining the liquid level of the hydrogen peroxide solution 20 through steps (b) to (d) described later.

[0096] 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 ion exchange resin 10 to prevent a portion of the 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 .

[0097] In this way, by preventing a portion of the ion exchange resin 10 from being exposed and dried due to not being immersed in the hydrogen peroxide solution 20, the gas generation during the purification process of the hydrogen peroxide solution can be minimized, and even without increasing the equipment, the risk of explosion in the process due to the generation of gas can be prevented, and the generation of impurities caused by the gas can be minimized to improve the purification efficiency.

[0098] In consideration of the control of the gas generated in the refining tower 100 and the refining efficiency of the hydrogen peroxide solution, the ion exchange resin 10 may be filled to a height of 30 to 90%, preferably 30 to 80%, and more preferably 30 to 70% of the internal height of the refining tower 100. The ion exchange resin 10 may be selected from cation exchange resins, anion exchange resins, or mixed ion exchange resins, wherein in consideration of the refining efficiency of the hydrogen peroxide solution, a mixed ion exchange resin in which a cation exchange resin and anion exchange resin are mixed is preferably used.

[0099] 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.

[0100] The anion exchange resin is not particularly limited as long as it can remove anionic impurities in hydrogen peroxide water, and can be one or more selected from the group consisting of strongly basic anion exchange resins that are resins having quaternary ammonium groups on a styrene skeleton. The cation exchange resin and the anion exchange resin can be contained in a volume ratio of 0.8:1.0 to 1.0:0.8. When the above volume ratio is satisfied, it has the advantage of being able to effectively purify the impurities generated in each ion exchange resin, and is therefore preferred.

[0101] The method for purifying hydrogen peroxide water of the present invention may repeatedly implement the above step (a). In this case, the ion exchange resins 10 contained in the purification towers 100 may be of different types or of the same type.

[0102] (b) Step of discharging hydrogen peroxide solution

[0103] The method for purifying hydrogen peroxide solution of the present invention includes the step of discharging the hydrogen peroxide solution purified in the above step (a) through the discharge pipe 200 connected to the lower end of the purification tower 100 .

[0104] The discharge pipe 200 includes a liquid level holding pipe 210 , and the height of the hydrogen peroxide solution 20 in the refining tower 100 can be adjusted in conjunction with the maximum height of the liquid level holding pipe 210 .

[0105] Therefore, it is preferable that the maximum height of the liquid level holding pipe 210 is greater than or equal to the height of the ion exchange resin 10 so that the ion exchange resin 10 in the refining tower 100 can be kept immersed in the hydrogen peroxide solution 20 .

[0106] When the maximum height of the liquid level holding tube 210 is higher than the height of the ion exchange resin 10 in the refining tower 100, the liquid level of the hydrogen peroxide solution 20 in the refining tower 100 can also be maintained higher than the height of the ion exchange resin 10, thereby fundamentally preventing a portion of the ion exchange resin 10 in the refining tower 100 from being exposed and dried without being immersed in the hydrogen peroxide solution 20.

[0107] By maintaining the height of the hydrogen peroxide solution 20 in the purification tower 100 above the height of the ion exchange resin 10 by the liquid level holding tube 210, sufficient time for the hydrogen peroxide solution to pass through the ion exchange resin can be ensured, thereby improving the purification efficiency and the purity of the purified hydrogen peroxide solution.

[0108] In addition, the maximum height of the liquid level holding tube 210 may be 110% or more, and preferably 120% or more, of the height of the ion exchange resin 10 in the refining tower 100. When the above numerical range is satisfied, there is an advantage that even if the liquid level of the hydrogen peroxide solution 20 in the refining tower 100 slightly shakes, the ion exchange resin can be fully immersed in the hydrogen peroxide solution, and thus even if the refining process is performed, there will be no exposed part of the ion exchange resin, thereby enabling more stable control of the generated gas.

[0109] In addition, the maximum height of the liquid level holding pipe 210 may be 140% or less, preferably 130% or less of the height of the ion exchange resin 10 in the refining tower 100. When the above numerical range is satisfied, there is an advantage that the resin layer will not be exposed even if the liquid level of the hydrogen peroxide solution in the refining tower fluctuates.

[0110] (c) Step of transferring to intermediate storage tank

[0111] 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 (b) to an intermediate storage tank 300 .

[0112] The liquid level of the hydrogen peroxide solution in the intermediate storage tank 300 is preferably greater than 30% of the internal height of the intermediate storage tank 300. When this is satisfied, it is advantageously possible to prevent the pump 400 from running idle due to a drop in the liquid level of the hydrogen peroxide solution.

[0113] (d) Steps of transferring via transfer pipe

[0114] The method for purifying hydrogen peroxide water of the present invention further includes a step of transferring the hydrogen peroxide water discharged in the above step (c) to a subsequent process or a final storage tank via a transfer pipe 500 having a pump 400. In the above transfer step, the pump 400 may provide a transfer thrust.

[0115] The transfer thrust provided by the pump 400 is preferably adjusted to a constant strength so as to maintain the liquid level of the intermediate storage tank 300 in the step (c) above, thereby being able to constantly adjust the flow rate transferred through the transfer pipe 500 .

[0116] In this way, by stably maintaining the liquid level of the hydrogen peroxide solution in the intermediate storage tank 300 , the liquid level of the hydrogen peroxide solution in the refining tower 100 can also be stably maintained.

[0117] 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.

[0118] 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.

[0119] <Examples and Comparative Examples>

[0120] Example 1

[0121] according to Figure 1 The purification device and the method for purifying hydrogen peroxide water using the same purify hydrogen peroxide water. Specifically, a mixed ion exchange resin (a 1:1 mixture of cation exchange resin and anion exchange resin) is filled in a purification tower having an inner diameter of 700 mm and an inner height of 3600 mm until it reaches 33.3% (1200 mm) of the inner height of the purification tower, and unpurified hydrogen peroxide water (31%, impurity level of 10 ppb) is introduced through the introduction pipe at the upper part of the purification tower, and the temperature is maintained below 15°C.

[0122] The cation exchange resin of the mixed ion exchange resin is a strongly acidic ion exchange resin having a sulfonic acid group as a functional group, an ion exchange capacity of 2.0 eq / L, and an effective acidity of pH 0 to 14, and the anion exchange resin is a strongly basic ion exchange resin having a quaternary ammonium group as a functional group, an ion exchange capacity of 1.0 eq / L, and an effective acidity of pH 1 to 14.

[0123] The purified hydrogen peroxide solution having 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 refining tower and including a liquid level holding pipe having a maximum height of 1200 mm. The purity of the discharged hydrogen peroxide solution and the amount of gas generated in the refining tower were evaluated as follows. The results are shown in Table 2 below.

[0124] Examples 2 to 5

[0125] In the above-mentioned Example 1, purification was carried out by the same method except that the maximum height of the liquid level holding tube was set to the height shown in the following Table 1.

[0126] Example 6

[0127] according to Figure 2The purification device and the method for purifying hydrogen peroxide water using the same purify hydrogen peroxide water. That is, in the above-mentioned embodiment 1, the hydrogen peroxide water discharged through the discharge pipe is transferred to the intermediate storage tank 300 (inner diameter 1000mm, inner height 1500mm) equipped with a pump 400 at the lower end, and the height of the hydrogen peroxide water transferred to the above-mentioned intermediate storage tank is adjusted to be maintained at 30% of the inner height of the intermediate storage tank.

[0128] Examples 7 to 9

[0129] In Example 6, purification was performed by the same method as in Example 6 above, except that the level of hydrogen peroxide in the intermediate storage tank was set to the level shown in Table 1.

[0130] Examples 10 to 12

[0131] In the above-mentioned Example 9, purification was carried out by the same method except that the maximum height of the liquid level holding tube was set to the height shown in the following Table 1.

[0132] Comparative Example 1

[0133] In Example 1, the purified hydrogen peroxide solution through which the mixed ion exchange resin had flowed was discharged through a discharge pipe connected to the lower end of the refining tower but not including a liquid level holding pipe, and the height of the hydrogen peroxide solution in the refining tower was as shown in Table 1. The purity of the discharged hydrogen peroxide solution and the amount of gas generated in the refining tower were evaluated as follows, and the results are shown in Table 2 below.

[0134] Comparative Example 2

[0135] In Example 1, a discharge pipe including a liquid level holding pipe having a maximum height of 500 mm connected to the lower end of the refining tower was used, and the height of the hydrogen peroxide solution in the refining tower was as shown in Table 1. The purity of the discharged hydrogen peroxide solution and the amount of gas generated in the refining tower were evaluated as follows, and the results are shown in Table 2 below.

[0136] 1. Purity evaluation method of purified hydrogen peroxide water

[0137] The sodium ion concentration of the hydrogen peroxide water purified by the above-mentioned examples and comparative examples was measured for 2 months in units of one day 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 2.

[0138] <Purity Evaluation Criteria for Purified Hydrogen Peroxide>

[0139] ◎: Average sodium ion concentration is below 0.005 ppb

[0140] ○: Average sodium ion concentration is greater than 0.005 ppb and less than 0.01 ppb

[0141] △: Average sodium ion concentration is greater than 0.01 ppb and less than 0.02 ppb

[0142] ×: Average sodium ion concentration greater than 0.02 ppb

[0143] 2. Evaluation method of gas generation in refining tower

[0144] A gas flow meter was installed at the top of the refining tower to measure the gas generation amount in one week, and evaluation was performed according to the following evaluation criteria. The results are shown in Table 2 below.

[0145] <Evaluation criteria for gas generation in refining tower>

[0146] ○: Gas generation is less than 7L / hr

[0147] △: Gas generation is 7L / hr or more and less than 10L / hr

[0148] ×: Gas generation is 10L / hr or more

[0149] [Table 1]

[0150]

[0151] (*: Since the liquid level of hydrogen peroxide solution is lower than that of ion exchange resin, it cannot be measured.)

[0152] [Table 2]

[0153] Purity of purified hydrogen peroxide water Gas generation in the refining tower Example 1 ○ △ Example 2 ◎ ○ Example 3 ◎ ○ Example 4 ◎ ○ Example 5 ○ ○ Example 6 ◎ △ Example 7 ◎ ○ Example 8 ◎ ○ Example 9 ◎ ○ Example 10 ◎ ○ Embodiment 11 ◎ ○ Example 12 ◎ ○ Comparative Example 1 △ × Comparative Example 2 △ ×

Claims

1. A method for purifying hydrogen peroxide water, characterized in that: include: (a) supplying the hydrogen peroxide solution to a refining tower containing an ion exchange resin to purify the hydrogen peroxide solution; as well as (b) discharging the hydrogen peroxide solution through a discharge pipe connected to the lower end of the refining tower and including a liquid level maintaining pipe, In the step (a), the hydrogen peroxide solution flows from the top to the bottom of the ion exchange resin. In the step (b), the maximum height of the liquid level holding tube is greater than or equal to the height of the ion exchange resin in the refining tower. 2 . The method for purifying hydrogen peroxide solution according to claim 1 , wherein the maximum height of the liquid level holding tube is 110% or more of the height of the ion exchange resin in the purification tower. 3 . The method for purifying hydrogen peroxide solution according to claim 1 , wherein the maximum height of the liquid level holding tube is 120% or more of the height of the ion exchange resin in the purification tower. 4 . The method for purifying hydrogen peroxide solution according to claim 1 , wherein the maximum height of the liquid level holding tube is 140% or less of the height of the ion exchange resin in the purification tower. 5 . The method for purifying hydrogen peroxide solution according to claim 1 , wherein the maximum height of the liquid level holding tube is 130% or less of the height of the ion exchange resin in the purification tower.

6. The method for purifying hydrogen peroxide water according to claim 1, wherein the ion exchange resin is a mixed ion exchange resin formed by mixing a cation exchange resin and an anion exchange resin.

7. The method for purifying hydrogen peroxide water according to claim 1, further comprising, after step (b): (c) a step of transferring the hydrogen peroxide solution discharged in step (b) to an intermediate storage tank; as well as (d) 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. 8 . The method for purifying hydrogen peroxide solution according to claim 7 , 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.

9. The method for purifying hydrogen peroxide solution according to claim 7, wherein in the step (d), the pump provides the transfer thrust.

10. The method for purifying hydrogen peroxide water according to claim 1, characterized in that: The purification method further improves the purity of the purified hydrogen peroxide water by repeating the entire process including the steps (a) and (b).

11. A hydrogen peroxide water purification device, comprising: a refining tower equipped with an ion exchange resin; and a discharge pipe connected to the lower end of the refining tower and having a liquid level maintaining pipe, The maximum height of the liquid level holding tube is greater than or equal to the height of the ion exchange resin in the refining tower. 12 . The hydrogen peroxide water purification device according to claim 11 , wherein the maximum height of the liquid level holding pipe is 110% or more of the height of the ion exchange resin in the purification tower. 13 . The hydrogen peroxide water purification device according to claim 11 , wherein the maximum height of the liquid level holding pipe is 120% or more of the height of the ion exchange resin in the purification tower. 14 . The hydrogen peroxide water purification device according to claim 11 , wherein the maximum height of the liquid level holding pipe is 140% or less of the height of the ion exchange resin in the purification tower. 15 . The hydrogen peroxide water purification device according to claim 11 , wherein the maximum height of the liquid level holding pipe is 130% or less of the height of the ion exchange resin in the purification tower. 16 . The hydrogen peroxide water purification device according to claim 11 , wherein the ion exchange resin is a mixed ion exchange resin formed by mixing a cation exchange resin and an anion exchange resin. 17 . The hydrogen peroxide water purification device according to claim 11 , further comprising an intermediate storage tank connected to the discharge pipe. 18 . The hydrogen peroxide water purification device according to claim 17 , wherein the rear end of the intermediate storage tank is connected to a transfer pipe, and the transfer pipe includes a pump.

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