TW201930200A - Method and apparatus for removing hydrogen peroxide - Google Patents

Abstract

A method and an apparatus both for decomposing and removing hydrogen peroxide by flowing water containing hydrogen peroxide through columns 21 to 25 each filled with a platinum-based catalyst, wherein the hydrogen peroxide removal performance can be recovered by halting the flowing of the water through one or some of the columns at a predetermined point of time and storing the platinum-based catalyst in the columns in ultra-pure water. It is possible to flow a nitrogen gas or hydrogen-dissolved water through the columns through which the flowing of the water is halted at the predetermined point of time, and it is also possible to increase the volume of the water to be flowed through the other columns.

Description

Hydrogen peroxide removal method and device

The invention relates to a method and a device for removing hydrogen peroxide in water in the manufacturing step of pure water. In the present invention, pure water includes ultrapure water.

Ultrapure water for cleaning semiconductors and electronic materials is a process for treating raw water (industrial water, tap water, etc.) by ultrapure water manufacturing equipment consisting of a pre-treatment device, a primary pure water manufacturing device, and a secondary pure water manufacturing device (subsystem). Well water, etc.).

The pre-treatment device formed by agglomeration, pressurized floatation (precipitation), filtration (membrane filtration) device, etc. is used to remove suspended substances or colloidal substances in raw water. Moreover, in this process, it is possible to remove polymer-based organic substances, hydrophobic organic substances, and the like.

It is equipped with a reverse osmosis membrane separation device, degassing device and ion exchange device (mixed bed type or 4 bed 5 tower type, etc.) primary pure water production device, which is used to remove ions or organic components in raw water. In the reverse osmosis membrane separation device to remove salts and ionic and colloidal TOC. In the ion exchange device, the salts are removed, and the TOC component by adsorption or ion exchange is removed by the ion exchange resin. In the degassing device, the inorganic carbon (IC) and dissolved oxygen are removed.

The primary pure water from the primary pure water manufacturing device is processed in the auxiliary system by ultraviolet (UV) irradiation device, ion exchange device and ultrafiltration (UF) membrane separation device to produce ultrapure water. The UV oxidation device decomposes TOC into organic acids and then into CO ₂ by 185 nm UV irradiated from a UV lamp. The organic matter and CO ₂ generated by the decomposition are removed in an ion exchange device (usually a mixed bed type ion exchange device) in the latter stage. In the UF membrane separation device, remove the fine particles, and also remove the fragments of the ion exchange resin flowing out from the ion exchange resin. The ultrapure water thus obtained is supplied to the point of use.

The oxidation treatment by ultraviolet irradiation using an ultraviolet oxidation device decomposes organic matter (TOC component) in water and produces organic acids and carbonic acid. The oxidative decomposition mechanism of the TOC component in the ultraviolet oxidizing device is to oxidize and decompose water to generate OH radicals, and the OH radical oxidizes and decomposes the TOC component. Irradiation.

When there is a large amount of ultraviolet irradiation in this way, the OH radicals generated by the decomposition of water become excessive, so that the remaining OH radicals associate to generate hydrogen peroxide. The generated hydrogen peroxide decomposes when it comes into contact with an anion exchange resin of a mixed bed ion exchange device described later, but at this time, the ion exchange resin is deteriorated. With this decomposition, dissolved oxygen also increases. Moreover, due to the decomposition of the ion exchange resin, a new TOC component derived from the ion exchange resin is generated, which reduces the water quality of the obtained ultrapure water. In addition, the hydrogen peroxide remaining after the mixed bed type ion exchange device passes water deteriorates the degassing device or the UF membrane in the subsequent stage of the mixed bed type ion exchange device.

Patent Document 1 describes, as a method for removing hydrogen peroxide in ultrapure water, the hydrogen peroxide-containing treated water discharged from the ultraviolet oxidation treatment device of the ultrapure water production device and the platinum group metal nanocolloid particles Hydrogen peroxide decomposition catalyst supported on anion exchange resin carrier is contacted to decompose hydrogen peroxide in the treated water to below 1 ppb.

Patent Document 2 describes that in order to suppress the deterioration of the platinum catalyst, after the water to be treated is subjected to ultraviolet oxidation treatment with an ultraviolet oxidation device, the method for producing pure water using a platinum-based catalyst to perform hydrogen peroxide removal treatment, the ultraviolet The TOC of the water supply of the oxidation device is set to 5 ppb or less.

[Patent Literature 1] Japanese Patent Application Publication No. 2007-185587 [Patent Literature 2] Japanese Patent Application Publication No. 2015-93226

As mentioned above, the platinum group catalyst system represented by Pt has been used for decomposition of oxidizing substances. In the ultrapure water production system, the removal of hydrogen peroxide as a by-product in the ultraviolet oxidation step for the purpose of decomposing organic substances contained in water has become a problem in recent years. Hydrogen peroxide decomposition treatment of ion exchange resin or Pt support resin.

Through the hydrogen peroxide decomposition treatment, the concentration of hydrogen peroxide in the treated water can be reduced to below the target concentration (for example, 1 ppb), but the catalyst performance decreases with long-term use.

The purpose of the present invention is to provide a method and a device for removing hydrogen peroxide that can suppress the reduction of the performance of the platinum-based catalyst or restore its performance, and can maintain the state of having sufficient catalyst activity for a long time.

Generally, by reducing the concentration of organic matter in the water to be treated flowing into the platinum-based catalyst device, the performance degradation of the platinum-based catalyst is suppressed. The present inventors repeated active research in order to further suppress performance degradation. As a result, it was found that the oxidation of the catalyst surface is also one of the reasons for the performance degradation of the platinum catalyst. By suppressing the oxidation of the catalyst surface, the performance degradation of the platinum catalyst can be suppressed.

The present invention was completed based on this knowledge.

The hydrogen peroxide removal method of the present invention is a hydrogen peroxide removal method in which a hydrogen peroxide removal device having a platinum-based catalyst filled container arranged in parallel is passed through water containing hydrogen peroxide and hydrogen peroxide is removed. Hydrogen peroxide removal performance recovery operation is performed by stopping the passage of water containing hydrogen peroxide to a part of the platinum catalyst-filled container, and storing the platinum catalyst filled in the container in ultrapure water for a specific time.

In one aspect of the present invention, the hydrogen peroxide removal performance recovery operation is to replace the water in the container where the water passage has been stopped with ultrapure water, and store the platinum-based catalyst in the ultrapure water in the container to store specific During the operation.

In one aspect of the present invention, the hydrogen peroxide removal performance recovery operation is to take out the platinum catalyst in the container from which the water flow has been stopped, and store the taken platinum catalyst in ultrapure water for a specific period , Then refill the container.

In one aspect of the present invention, non-oxidizing gas such as nitrogen is supplied to the ultrapure water.

In one aspect of the invention, the aforementioned ultrapure water is ultrapure water in which hydrogen has been dissolved.

In one aspect of the present invention, the hydrogen peroxide removal device is provided in an ultrapure water production device, and the water flow rate to the platinum-based catalyst-filled container other than the aforementioned part is increased within the specified time.

The hydrogen peroxide removal device of the present invention is provided with platinum-based catalyst-filled containers arranged in parallel, a hydrogen peroxide-containing water passage means for passing hydrogen peroxide-containing water into each container, and supplying non-oxidizing properties to each container The means for supplying gas or hydrogen-dissolved water, and the means for switching the supply of hydrogen peroxide-containing water to non-oxidizing gas or hydrogen-dissolved water in each container. [Effect of the invention]

The catalyst has the function of not changing itself, which can lower the barrier of certain chemical reactions and promote the progress. The catalyst surface is oxidized due to long-term exposure to oxidizing conditions, thus causing a decrease in catalyst performance.

Platinum-based catalysts become irreversible oxides if they undergo strong oxidation, but during the reversible surface oxidation stage, they can be recovered and restored by releasing from the continuous oxidation state. The inventors found that by stopping the water flow and immersing the platinum-based catalyst in ultrapure water for storage, the platinum-based catalyst can be released from the continuous state and the catalyst performance can be restored. During the stop of the water passing, the hydrogen peroxide decomposition performance can be restored in a shorter time by introducing N ₂ gas in ultra-pure water or ultra-pure water in which hydrogen is dissolved.

The reason for the deterioration of the catalyst is not only the deterioration caused by the surface oxidation of the platinum group catalyst itself, but also the pollution caused by impurities such as organic substances contained in the treated water. Moreover, the substrate, that is, the carrier (for example, ion exchange resin) itself may deteriorate. Therefore, when there are few impurities in the water to be treated, and the hydrogen peroxide concentration is relatively high, the oxidation becomes the main cause of performance degradation, so the present invention becomes effective.

According to the present invention, the effective period of the platinum-based catalyst can be extended without replacing the platinum-based catalyst with a new product.

Multiple platinum-based catalyst-filled containers are arranged in parallel, and during the performance recovery process of some containers, by sequentially repeating the water flow switching operation of setting the water flow rate to other containers to a higher level, the desired treatment water quality can be maintained With the amount of water, hydrogen peroxide decomposition treatment is carried out for a long period of time.

Hereinafter, the present invention will be described in further detail.

The method and device for removing hydrogen peroxide of the present invention can be preferably used in the ultrapure water manufacturing step. In the ultrapure water production step, as described above, the primary pure water from the primary pure water production device is processed by the auxiliary system to produce ultrapure water. In the sub-system, once the pure water is treated with an ultraviolet oxidation device, the hydrogen peroxide removal treatment is carried out with a hydrogen peroxide removal device with a platinum catalyst, followed by a non-regenerative ion exchange device, membrane degassing device, UF membrane Device.

The TOC component is oxidized and decomposed by the ultraviolet oxidation treatment of the ultraviolet oxidation device to generate organic acid and carbonic acid, and hydrogen peroxide is generated. In the present invention, the outflow water from the ultraviolet oxidation device passes through the hydrogen peroxide removal device to remove hydrogen peroxide. As the hydrogen peroxide removal device, a container filled with a platinum catalyst is used. The platinum-based catalyst is preferably a colloidal particle of a platinum-based metal, and particularly preferably supports nanocolloid particles on a carrier.

Examples of platinum-based metals include ruthenium, rhodium, palladium, osmium, iridium, and platinum. These platinum group metals may be used alone or in combination of two or more, or as two or more alloys, or the purified product of a naturally produced mixture may be used without separating into monomers. Among these, platinum, palladium, platinum / palladium alloy alone or a mixture of two or more of these can be used particularly well because of their strong catalytic activity.

The method of producing the nanocolloid particles of platinum-based metal is not particularly limited, and examples thereof include a metal salt reduction reaction method and a combustion method. Among these, the metal salt reduction reaction method is easy to manufacture and can be used well because it can obtain metal nanocolloid particles of stable quality.

The average particle diameter of the platinum-based metal nanocolloid particles is preferably 1 to 50 nm, more preferably 1.2 to 20 nm, and still more preferably 1.4 to 5 nm. The particle size is a value obtained from imaging with an electron microscope.

Examples of the carrier that supports the platinum-based metal nanocolloid particles include magnesium oxide, titanium oxide, aluminum oxide, silica-alumina, zirconium oxide, activated carbon, zeolite, diatomaceous earth, and ion exchange resin. Among these, anion exchange resins can be particularly preferably used. The platinum-based metal nanocolloid particles have an electric double layer, and since they are negatively charged, they are stably supported by the anion exchange resin and become difficult to peel. The platinum-based metal nanocolloid particles supported on the anion exchange resin show strong catalytic activity for the decomposition and removal of hydrogen peroxide. The exchange group of the anion exchange resin is preferably OH form. The OH-type anion exchange resin becomes alkaline on the surface of the resin, which promotes the decomposition of hydrogen peroxide.

The supporting amount of the platinum-based metal nanocolloid particles to the anion exchange resin is preferably 0.01 to 0.2% by weight, more preferably 0.04 to 0.1% by weight.

By bringing the water containing hydrogen peroxide into contact with the hydrogen peroxide decomposition catalyst holding platinum-based metal nanocolloid particles on the carrier, the hydrogen peroxide in the water reacts by 2H ₂ O ₂ à2H ₂ O + O ₂ And decomposition.

The flow rate of water containing hydrogen peroxide to the platinum-based catalyst filled container is preferably space velocity SV100 ~ 2,000h ^-1 , more preferably 300 ~ 1,500h ^-1 . The platinum catalyst has a very rapid decomposition rate of hydrogen peroxide, so even if the SV is 100h ^-1 or more, hydrogen peroxide can be fully decomposed. However, when the SV exceeds 2,000h ^-1 , there is a possibility that the pressure loss of passing water is too large and the decomposition and removal of hydrogen peroxide may become insufficient.

A specific example of the method and device for removing peroxide according to the present invention will be described with reference to FIGS. 1 and 2.

In FIG. 1, a plurality of columns (five shown in the figure) filled with platinum-based catalysts 21 to 25 are arranged in parallel. Hydrogen peroxide-containing water, such as water flowing out of the ultraviolet irradiation device, passes from the pipe 1 to the columns 21 to 25 via the valves 11 to 15. The effluent water from the columns 21 to 25 is taken out through the valves 31 to 35 and the collection piping 2.

Treat with 5 pipes 21 ~ 25 juxtaposed to pass water. When seeing the signs of water degradation, as shown in Figure 1 (b), by closing the valves 11, 31, stop the flow of water to one pipe string (Figure 1 (b) is the pipe string 21). The flow rates of the columns 22 to 25 are increased by 25% respectively to ensure the parallel operation of the treated water.

For the column 21 whose water flow has been stopped, the hydrogen peroxide removal performance recovery operation is performed as follows. (1) The water in the column 21 is replaced with ultrapure water, and the platinum-based catalyst in the column 21 is immersed in the ultrapure water in the column 21 for a specific period of time. (2) The platinum catalyst in the column 21 is temporarily withdrawn, immersed in ultrapure water in another container and stored for a specific period, and then filled in the column 21 again. (3) In the operation of (1) or (2) above, non-oxidizing gas such as N ₂ gas is supplied to the ultrapure water used for the immersion treatment of the platinum catalyst. (4) In the operation of (1) or (2) above, the ultrapure water used for the impregnation treatment of the platinum-based catalyst uses ultrapure water in which hydrogen is dissolved. The above operations (1) to (4) can also be performed in combination of two or more.

The ultrapure water used for the immersion treatment of the platinum catalyst does not contain hydrogen peroxide, preferably the hydrogen peroxide concentration is less than 2 μg / L, particularly preferably less than 1 μg / L.

In the present invention, the specific period for storing the platinum-based catalyst in ultrapure water is preferably 1 day or more, and particularly preferably 2 days to 2 weeks or so.

In addition, in the present invention, in addition to the above operations (1) to (4), it is also possible to perform an operation of replacing the atmosphere in the column 21 with a non-oxidizing gas such as N ₂ gas or to pass water in which hydrogen is dissolved operating.

After performing the above-mentioned hydrogen peroxide removal performance recovery operation, it is preferable to test-pass water to the pipe string 21, and after confirming that the treated water quality is good, open the valves 11, 31 to start water flow to the pipe string 21 again. Subsequently, the same performance recovery operation was also performed for other columns 22 to 25 in order to restore the performance to a good state.

After all the 5 pipes 21 to 25 have been completely restored, they will return to use the 5 parallel flow of the original standard flow.

Fig. 2 shows that instead of valves 11 to 15, three-way valves 41 to 45 are provided, and instead of valves 31 to 35, three-way valves 51 to 55 are provided. By switching the three-way valves 31 to 35 and 51 to 55, Each column 21 to 25 is supplied with a hydrogen peroxide removal device for ultrapure water, N ₂ gas, or hydrogen dissolved water.

The piping 61 to 65 branched from the piping 60 are connected to the third port of the three-way valves 41 to 45. The third ports of the three-way valves 51 to 55 are connected to the discharge pipe 70 via branch pipes 71 to 75. The self-piping 60 supplies ultrapure water, N ₂ gas, or hydrogen-dissolved water to any one of the columns 21 to 25, and the outflow gas or outflow water is discharged from the piping 70.

In addition, as shown in FIGS. 1 and 2, when each of the columns 21 to 25 of the hydrogen peroxide removal device with five columns 21 to 25 in parallel is fed with water at a standard SV of 400 / h, if one is restored When the treatment becomes four parallel water passes (for example, FIG. 1 (b)), the SV of each column increases to 500 / h. This is undesirable in terms of treatment water quality maintenance. However, the hydrogen peroxide decomposition life of platinum-based resins (when no recovery treatment is applied) is several years, and the recovery treatment time is about 1 week per piece. Therefore, a 25% increase in the burden time is applied to each column It is about 4 weeks long. During this period, it is not difficult to maintain the treated water volume (SV500 / h) as the entire hydrogen peroxide removal device because the water flow to the recovery performance string is resumed in sequence.

In Figures 1, 2 series, 5 pipes are arranged in parallel, but 6 pipes can be arranged in parallel, and one of them is stopped in sequence (performance recovery operation). Usually, 5 pipes are run with water.

In this case, even after a certain period of time (a specific hydrogen peroxide load), you can still stop one of them and start watering the one that is not used at the same time. For 5/6 of the whole time, the so-called carousel-type operation of intermittent operation for 1/6 of the time is stopped, and it can be operated with a margin.

Based on the experimental results of the present inventors, it is confirmed as follows. (1) After the water flow through the treated container filled with the platinum-based catalyst is stopped for a certain period of time and the water flow starts again, the hydrogen peroxide decomposition performance is restored. The longer the stop time, the higher the degree of recovery. (2) Adding the operation of removing O ₂ from the container by venting the treated water to the platinum-based catalyst-filled container by aeration with N ₂ gas, the result was seen to be shorter than (1) Restore hydrogen peroxide decomposition performance. (3) While the flow of treated water to the platinum catalyst filled container is stopped, the water in the container is replaced with ultrapure water, and the platinum catalyst in the container is immersed and stored in the ultrapure water, As a result, the hydrogen peroxide decomposition performance was restored in a shorter time than (1) and (2). (4) While the flow of treated water to the platinum-based catalyst-filled container is stopped, the platinum-based catalyst is temporarily pulled out of the container, immersed in another container and stored in ultrapure water at a specific time, then refilled and refilled Starting to pass water, as a result, the hydrogen peroxide decomposition performance was restored in a shorter time than the above (1) to (3). (5) While the flow of treated water to the platinum-based catalyst-filled container was stopped, ultra-pure water with dissolved hydrogen was introduced, and as a result, hydrogen peroxide was recovered in a shorter time than the above (1) to (4). Decomposition performance.

The above-mentioned embodiment is an example of the present invention, and the present invention may be an embodiment other than the above. For example, the pipe string is not limited to five. [Example]

[Reference Example 1] prepared as shown in Fig. 3 as an ultrapure water production device. The ultrapure water production device 81 is a three-stage device composed of a pretreatment device 82, a primary pure water production device 83, and a secondary pure water production device (subsystem) 84. In the pretreatment device 82 of the ultrapure water production device 81, the raw water W is filtered, coagulated and precipitated, and pre-processed using a precision filtration membrane.

The primary pure water production device 83 has a tank 85 for pre-treatment water W1, a reverse osmosis (RO) membrane device 86, an ultraviolet (UV) oxidation device 87, and a regenerative ion exchange device (mixed bed type or 4 bed 5 tower type, etc.) 88 、 Membrane degassing device 89.

The sub-system 84 is composed of the following: a sub-tank 91 that stores the primary pure water W2 manufactured in the primary pure-water manufacturing device 83, and treatment of ultraviolet oxidation of the primary pure water W2 sent from the sub-tank 91 via a pump not shown An apparatus 92, a platinum group metal catalyst resin tower 93, a membrane degasser 94, a non-regenerating mixed bed ion exchange apparatus 95, and an ultrafiltration (UF) membrane 96 as a membrane filtration apparatus. The ultrafiltration (UF) membrane 96 removes fine particles to become ultrapure water W3, which is supplied to the use point 97, and unused ultrapure water is refluxed in the sub tank 91.

The platinum nanocolloid particles with an average particle diameter of 3.5 nm are supported on a strong alkaline gel-type anion exchange resin at a support amount of 0.07% by weight, and a platinum group metal nanoparticle is prepared as a platinum group metal catalyst resin. Particle anion exchange resin.

In the ultrapure water production apparatus 81 of the device configuration shown in FIG. 3, the platinum group metal catalyst resin tower 93 is used to manufacture ultrapure water W3 using the platinum group metal catalyst resin, and the platinum group metal catalyst resin of the sub-system 84 is measured The hydrogen peroxide concentration of the inlet water and outlet water of the tower 93 (initial). The results are shown in Table 1. Moreover, the hydrogen peroxide concentration of the outlet water of the platinum group metal catalyst resin tower 93 after the operation of the ultrapure water production device 81 was continued for a long period of time (final period) was measured. The results are summarized in Table 1.

In order to measure the hydrogen peroxide concentration, sodium sulfate (anhydrous) was added to 4.8 mg of phenolphthalein, 8 mg of copper sulfate (anhydrous), and 48 mg of sodium hydroxide to make 10 g, and a trace amount of hydrogen peroxide concentration measurement reagent was prepared. 0.5 g of this sample was added to and dissolved in 10 mL of the test water, and after standing at room temperature for 10 minutes, the absorbance at 552 nm was measured, and the hydrogen peroxide concentration was calculated based on the measured value.

[Table 1]

As understood from Table 1, the hydrogen peroxide concentration of ultrapure water W3 after a long period of operation increases significantly.

[Reference Example 2] In Reference Example 1, the used resin of the platinum group metal catalyst resin tower 93 after long-term operation was taken out and filled in the test column to make a platinum group metal catalyst resin tower for the test. In addition, for comparison, a new-type resin was similarly packed in a test column to make a platinum group metal catalyst resin tower.

Add 300μg / L or 1000μg / L of hydrogen peroxide to ultrapure water (less than 1μg / L of hydrogen peroxide), prepare the test inlet water, and measure the test inlet water at the water flow rate (SV) 300 hr ^{-1 is} the concentration of hydrogen peroxide in the outlet water after the above test column is passed down. The results are shown in Table 2.

[Table 2]

As understood from Table 2, the concentration of hydrogen peroxide in the outlet water of the used resin of the platinum group metal catalyst resin tower 93 after long-term operation is higher than that of the new product. From this, it can be seen that the decomposition energy of hydrogen peroxide decreases.

[Reference Example 3] In Reference Example 1, the used column of the platinum group metal catalyst resin tower 93 after long-term operation was filled in the test column to prepare a platinum group metal catalyst resin tower for the test. In addition, for comparison, a new-type resin was similarly packed in a test column to make a platinum group metal catalyst resin tower.

Add 30μg / L of hydrogen peroxide to ultrapure water (less than 1μg / L of hydrogen peroxide) to prepare the inlet water, and measure the inlet water at the water flow rate (SV) 400hr ^-1 for each test column The hydrogen peroxide concentration (No. 1) in the outlet water after the lower pass. The results are shown in Table 3.

In addition, as a load test, 400 μg / L of hydrogen peroxide was added to ultrapure water (less than 1 μg / L of hydrogen peroxide) to prepare test inlet water, and the test inlet water was passed at a water flow rate (SV) of 6400 hours ^-1 Stop the operation after passing the above test string downward for 22 hours. Next, 30μg / L of hydrogen peroxide inlet water was added to the ultrapure water (less than 1μg / L of hydrogen peroxide) and passed into each test column. After 5 minutes (No. 2) and 60 minutes ( No.3) The hydrogen peroxide concentration in the outlet water. The results are shown in Table 3.

[table 3]

[Example 1] After the test of Reference Example 3, the resin of each test column was taken out, stored in ultrapure water (less than 1μg / L of hydrogen peroxide) for 2 weeks, and filled again, and the measurement will be carried out in ultrapure water ( The hydrogen peroxide concentration of the outlet water when the inlet water of 30 µg / L hydrogen peroxide is added to the inlet water of hydrogen peroxide less than 1 µg / L). The results are shown in Table 4.

[Table 4]

It can be seen from Table 4 that by storing the used platinum catalyst in ultrapure water for a specific period, its hydrogen peroxide removal performance can be restored.

Although the present invention is described in detail using specific aspects, those skilled in the art should understand that various changes can be made without departing from the intention and scope of the present invention. This application is based on Japanese Patent Application No. 2017-240802 filed on December 15, 2017, the entire contents of which are incorporated by reference.

11 ~ 15, 31 ~ 35‧‧‧Valve

21 ~ 25‧‧‧Column

41 ~ 45, 51 ~ 55‧‧‧Three-way valve

60 ~ 65‧‧‧Piping

70‧‧‧Exhaust piping

71 ~ 75‧‧‧ branch piping

81‧‧‧Ultra-pure water manufacturing device

82‧‧‧Pre-processing device

83‧‧‧Pure water manufacturing device

84‧‧‧Second pure water manufacturing device

85‧‧‧slot

86‧‧‧Reverse Osmosis (RO) membrane device

87‧‧‧Ultraviolet (UV) oxidation device

88‧‧‧ Regenerative ion exchange device

89‧‧‧membrane degassing device

91‧‧‧slot

92‧‧‧UV oxidation device

93‧‧‧Platinum metal catalyst resin tower

94‧‧‧membrane degassing device

95‧‧‧non-regenerative mixed bed ion exchange device

96‧‧‧Ultrafiltration (UF) membrane

97‧‧‧point of use

W1‧‧‧Pre-treatment water

W2‧‧‧One time pure water

W3‧‧‧Ultra-pure water

W‧‧‧raw water

FIG. 1 is an explanatory diagram of the method of the present invention. FIG. 2 is an explanatory diagram of an example of the device of the present invention. Figure 3 is a system diagram of an ultrapure water manufacturing device.

Claims (8)

A method for removing hydrogen peroxide, which is a method for removing hydrogen peroxide in which a hydrogen peroxide removal device having a platinum-based catalyst-filled container arranged in parallel is passed through water containing hydrogen peroxide and removes hydrogen peroxide. Hydrogen peroxide removal performance recovery operation is performed by stopping the passage of water containing hydrogen peroxide to a part of the platinum catalyst-filled container, and storing the platinum catalyst filled in the container in ultrapure water for a specific time. The method for removing hydrogen peroxide according to claim 1, wherein the hydrogen peroxide removal performance recovery operation is to replace the water in the container where the water passage has been stopped with ultrapure water, and replace the platinum-based catalyst in the container Store in pure water for a specific period of time. The hydrogen peroxide removal method according to claim 1, wherein the hydrogen peroxide removal performance recovery operation is to remove the platinum-based catalyst in the container from the container that has stopped passing the water, and remove the platinum-based catalyst in ultrapure water After the specific period is saved in the medium, the container is filled again. The hydrogen peroxide removal method according to any one of claims 1 to 3, wherein non-oxidizing gas is supplied to the aforementioned ultrapure water. The method for removing hydrogen peroxide according to claim 4, wherein the aforementioned non-oxidizing gas is nitrogen. The hydrogen peroxide removal method according to any one of claims 1 to 5, wherein the aforementioned ultrapure water is ultrapure water in which hydrogen has been dissolved. The hydrogen peroxide removal method according to any one of claims 1 to 6, wherein the hydrogen peroxide removal device is provided in an ultrapure water manufacturing device, and the platinum-based catalyst other than the above-mentioned part is added to the specific time within the specified time The water volume of the container. A hydrogen peroxide removal device, characterized by: juxtaposed platinum-based catalyst-filled containers, flow means for passing hydrogen peroxide-containing water into each container, supply non-oxidation to each container The supply means of sexual gas or hydrogen-dissolved water, and the switching means of switching the supply of hydrogen peroxide-containing water to non-oxidizing gas or hydrogen-dissolved water in each container.