A method for purifying hydrogen peroxide

Abstract

The invention discloses a method for purifying hydrogen peroxide. The method uses industrial-grade hydrogen peroxide as a raw material, adjusts its concentration to 30%-40%, controls the system feed temperature to be 0-5°C, and makes the treated hydrogen peroxide flow through n organic matter treatment units arranged in series in sequence; each treatment unit comprises an ultrasonic treatment device and a membrane filtration device which are connected in sequence, and in each treatment unit, the hydrogen peroxide is sequentially subjected to ultrasonic oscillation treatment and membrane filtration treatment; controls the residence time of the hydrogen peroxide in the latter ultrasonic treatment device to be greater than the residence time in the former ultrasonic treatment device; controls the pore size of the filter element of the latter membrane filtration device to be smaller than the pore size of the filter element of the former membrane filtration device; and in the method, in the organic matter removal stage, no additional resin tower is required, so that the hydrogen peroxide entering the subsequent anion and cation removal resin tower has a higher purity, the service life of the subsequent resin tower is improved, and the content of organic matter can be reduced to below 10 ppb.

Description

Technical Field

[0001] The invention relates to the technical field of hydrogen peroxide purification, and in particular to a method for purifying hydrogen peroxide. Background Art

[0002] Hydrogen peroxide, also known as hydrogen peroxide, is a blue viscous liquid that is soluble in water, alcohol, and ether, but insoluble in benzene and petroleum ether. Its aqueous solution is a colorless and transparent liquid. It is an important inorganic chemical product and is widely used in the fields of chemical industry, medicine, electronics, food, textile, papermaking, light industry, military industry, environmental protection, etc. Industrial hydrogen peroxide contains more organic impurities and cannot meet the needs of the electronics industry or the food industry, so it is necessary to remove the organic impurities in hydrogen peroxide.

[0003] At present, the purification method for industrial hydrogen peroxide is mostly to use multiple resin towers in series, and use resin adsorption and resin ion exchange for purification, specifically, an organic matter (TOC) resin adsorption tower, a cation exchange resin tower and an anion exchange resin tower are arranged in series. However, since the organic matter (TOC) content contained in industrial hydrogen peroxide is generally high and there are many ionic impurities, when the above-mentioned resin adsorption and anion and cation exchange methods are used, there is a large load and high energy consumption, and the resin filler in the resin tower needs to be frequently replaced or regenerated, which is too costly; and the strong oxidizing property, heat sensitivity and instability of hydrogen peroxide limit the application of various conventional purification methods.

[0004] In view of the above problems, Chinese patent CN112723316A discloses a purification method for removing organic matter from hydrogen peroxide at low temperature, which mainly includes a cooling stage and a filtering stage performed in sequence, wherein the cooling stage is to cool the industrial-grade hydrogen peroxide to 0-8°C (preferably 4-8°C), and the filtering stage is to filter the cooled hydrogen peroxide using a membrane filter to remove TOC. However, in the patent document, the organic matter (TOC) content of hydrogen peroxide treated by the purification method is still as high as tens of ppm, which is difficult to meet the high standard requirements of semiconductor-grade ultra-high purity hydrogen peroxide. Summary of the invention

[0005] The object of the present invention is to overcome one or more deficiencies of the prior art and to provide an improved method for purifying hydrogen peroxide, which method can eliminate the need for an additional resin tower in the organic matter (TOC) removal stage, thereby ensuring that the hydrogen peroxide entering the subsequent anion and cation removal resin tower has a higher purity, thereby increasing the service life of the subsequent resin tower, and the content of organic matter (TOC) in the hydrogen peroxide after treatment is less than 10 ppb.

[0006] To achieve the above object, the technical solution adopted by the present invention is: a method for purifying hydrogen peroxide, using industrial grade hydrogen peroxide as raw material, the purification method comprises:

[0007] The mass percentage concentration of industrial-grade hydrogen peroxide is adjusted to 30%-40%, and the system feed temperature is controlled to be 0-5°C, and then the treated hydrogen peroxide is sequentially passed through n organic treatment units arranged in series, where n is greater than or equal to 2;

[0008] Each of the organic matter treatment units independently comprises an ultrasonic treatment device and a membrane filtration device which are connected in sequence. In each of the organic matter treatment units, hydrogen peroxide is sequentially subjected to oscillation treatment by the ultrasonic treatment device and filtration treatment by the membrane filtration device;

[0009] Controlling the residence time of hydrogen peroxide in the ultrasonic treatment device included in the organic matter treatment unit of the next stage to be greater than the residence time in the ultrasonic treatment device included in the organic matter treatment unit of the previous stage;

[0010] The pore size of the filter element of the membrane filtration device included in the organic matter treatment unit of the next stage is controlled to be smaller than the pore size of the filter element of the membrane filtration device included in the organic matter treatment unit of the previous stage.

[0011] According to some preferred aspects of the present invention, n is 3, 4 or 5.

[0012] According to some preferred aspects of the present invention, the operating frequency of the ultrasonic processing device is 25-40 kHz.

[0013] According to some preferred aspects of the present invention, the residence time of hydrogen peroxide in the ultrasonic treatment device included in the organic matter treatment unit of the subsequent stage is controlled to be 1.2-3 times the residence time in the ultrasonic treatment device included in the organic matter treatment unit of the previous stage.

[0014] In some embodiments of the present invention, the residence time of hydrogen peroxide in the ultrasonic treatment device included in the subsequent organic matter treatment unit is controlled to be 1.2-1.5 times the residence time in the ultrasonic treatment device included in the previous organic matter treatment unit.

[0015] In some embodiments of the present invention, the residence time of hydrogen peroxide in the ultrasonic treatment device included in the subsequent organic matter treatment unit is controlled to be 1.5-2.0 times the residence time in the ultrasonic treatment device included in the previous organic matter treatment unit.

[0016] In some embodiments of the present invention, the residence time of hydrogen peroxide in the ultrasonic treatment device included in the subsequent organic matter treatment unit is controlled to be 2.0-3.0 times the residence time in the ultrasonic treatment device included in the previous organic matter treatment unit.

[0017] According to some preferred aspects of the present invention, the pore size of the filter element of the membrane filtration device included in the organic matter treatment unit of the subsequent stage is controlled to be 0.05-0.8 times the pore size of the filter element of the membrane filtration device included in the organic matter treatment unit of the previous stage.

[0018] In some embodiments of the present invention, the pore size of the filter element of the membrane filtration device included in the organic matter treatment unit of the subsequent stage is controlled to be 0.05-0.15 times the pore size of the filter element of the membrane filtration device included in the organic matter treatment unit of the previous stage.

[0019] In some embodiments of the present invention, the pore size of the filter element of the membrane filtration device included in the organic matter treatment unit of the subsequent stage is controlled to be 0.2-0.35 times the pore size of the filter element of the membrane filtration device included in the organic matter treatment unit of the previous stage.

[0020] In some embodiments of the present invention, the pore size of the filter element of the membrane filtration device included in the organic matter treatment unit of the subsequent stage is controlled to be 0.35-0.55 times the pore size of the filter element of the membrane filtration device included in the organic matter treatment unit of the previous stage.

[0021] In some embodiments of the present invention, the pore size of the filter element of the membrane filtration device included in the organic matter treatment unit of the subsequent stage is controlled to be 0.55-0.8 times the pore size of the filter element of the membrane filtration device included in the organic matter treatment unit of the previous stage.

[0022] According to some preferred and specific aspects of the present invention, when n is 3, the treated hydrogen peroxide is sequentially passed through a primary ultrasonic treatment device, a primary membrane filtration device, a secondary ultrasonic treatment device, a secondary membrane filtration device, a tertiary ultrasonic treatment device, and a tertiary membrane filtration device arranged in series.

[0023] According to some preferred and specific aspects of the present invention, the residence time of the first-stage ultrasonic treatment device, the residence time of the second-stage ultrasonic treatment device, and the residence time of the third-stage ultrasonic treatment device are controlled to be 5-15min, 15-25min, and 25-35min, respectively.

[0024] Furthermore, the residence time of the first-stage ultrasonic treatment device, the residence time of the second-stage ultrasonic treatment device, and the residence time of the third-stage ultrasonic treatment device are controlled to be 8-12 minutes, 18-22 minutes, and 28-32 minutes, respectively.

[0025] According to a specific aspect of the present invention, the residence time of the first-stage ultrasonic treatment device, the residence time of the second-stage ultrasonic treatment device, and the residence time of the third-stage ultrasonic treatment device are controlled to be 10 minutes, 20 minutes, and 30 minutes respectively.

[0026] According to some preferred and specific aspects of the present invention, the pore size of the filter element of the primary membrane filtration device, the pore size of the filter element of the secondary membrane filtration device, and the pore size of the filter element of the tertiary membrane filtration device are controlled to be 0.04-0.06μm, 0.005-0.015μm, and 0.5-10nm, respectively.

[0027] According to some specific aspects of the present invention, when the pore size of the filter element of the first-stage membrane filtration device is 0.04-0.06μm, it can be referred to as a microfiltration membrane filtration device; when the pore size of the filter element of the second-stage membrane filtration device is 0.005-0.015μm, it can be referred to as an ultrafiltration membrane filtration device; when the pore size of the filter element of the tertiary membrane filtration device is 0.5-10nm, it can be referred to as a RO reverse osmosis membrane filtration device.

[0028] According to some preferred aspects of the present invention, the filter element of the membrane filtration device is made of polytetrafluoroethylene.

[0029] According to some preferred and specific aspects of the present invention, the filtration pressure of the membrane filtration device is 0.5-0.8 MPa.

[0030] According to some preferred aspects of the present invention, the ultrasonic treatment device comprises an ultrasonic generator and a pipe arranged in the ultrasonic generator, and the length of the pipe is controlled to control the residence time of hydrogen peroxide in the ultrasonic treatment device.

[0031] According to some preferred and specific aspects of the present invention, the flow rate of the treated hydrogen peroxide in the organic matter treatment unit is 100 L / h to 200 L / h.

[0032] In some embodiments of the present invention, the specific process of the purification method is controlled to be carried out at an ambient temperature of less than or equal to 25°C.

[0033] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0034] Based on the problems of high energy consumption, complex operation and unsatisfactory purification effect in the prior art in purifying hydrogen peroxide, especially in removing organic matter in hydrogen peroxide, the present invention innovatively adopts a method of using ultra-low temperature and ultrasonic oscillation to assist membrane filtration to separate organic matter in hydrogen peroxide, further combines multi-stage sequential processing, controls the residence time of ultrasonic oscillation in each stage and adopts a mode of matching multi-stage apertures of membrane filtration, which can not only greatly and effectively reduce the content of organic impurities in hydrogen peroxide to ppb level, or even as low as below 10 ppb, so that high-purity hydrogen peroxide that meets the quality standards can be produced under the premise of ensuring continuous and stable production, and the method of the present invention does not need to pass through a resin tower additionally, so that the hydrogen peroxide entering the subsequent anion and cation removal resin tower has a higher purity, thereby improving the service life of the subsequent resin tower. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a process flow chart of the method for purifying hydrogen peroxide according to an embodiment of the present invention;

[0036] In the accompanying drawings, 1, pretreatment device; 2, first-stage ultrasonic treatment device; 3, first-stage membrane filtration device; 4, second-stage ultrasonic treatment device; 5, second-stage membrane filtration device; 6, third-stage ultrasonic treatment device; 7, third-stage membrane filtration device; 8, ultrasonic generator; 9, pipeline. DETAILED DESCRIPTION

[0037] The process flow chart of the method for purifying hydrogen peroxide in the embodiment of the present invention is as follows: Figure 1As shown, the mass percentage concentration of industrial-grade hydrogen peroxide is adjusted to 30%-40% by a pretreatment device 1, and the system feed temperature is controlled to be 0-5°C, which is lower than the cooling temperature in conventional operation. Under the system of the present invention, practice shows that it can better precipitate organic impurities in hydrogen peroxide, which can be more conducive to the removal of impurities by combining ultrasonic vibration with membrane filtration; then the treated hydrogen peroxide is sequentially passed through three organic treatment units arranged in series, specifically, the treated hydrogen peroxide is sequentially passed through a first-stage ultrasonic treatment device 2, a first-stage membrane filtration device 3, a second-stage ultrasonic treatment device 4, a second-stage membrane filtration device 5, a third-stage ultrasonic treatment device 6, and a third-stage membrane filtration device 7 arranged in series at a certain flow rate (preferably 100L / h~200L / h), wherein the residence time of the first-stage ultrasonic treatment device, the stop time of the second-stage ultrasonic treatment device, and the The residence time of the first-stage ultrasonic treatment device, the residence time of the second-stage ultrasonic treatment device and the residence time of the third-stage ultrasonic treatment device are 5-15min, 15-25min and 25-35min respectively, and the residence time of hydrogen peroxide in the latter-stage ultrasonic treatment device is 1.2-3 times of the residence time in the former-stage ultrasonic treatment device. The pore size of the filter element of the first-stage membrane filtration device, the pore size of the filter element of the second-stage membrane filtration device and the pore size of the filter element of the third-stage membrane filtration device are controlled to be 0.04-0.06μm, 0.005-0.015μm and 0.5-10nm respectively, and the pore size of the filter element of the latter-stage membrane filtration device is 0.05-0.8 times of the pore size of the filter element of the former-stage membrane filtration device. By simultaneously controlling the difference in the residence time and the pore size of the filter element, the organic matter can be removed more comprehensively and thoroughly, and the purity is greatly improved, so that the organic matter content can be basically below 10ppb, or even below 5ppb.

[0038] Furthermore, the ultrasonic treatment device includes an ultrasonic generator 8 and a pipe 9 arranged in the ultrasonic generator 8. The length of the pipe 9 is controlled to control the residence time of hydrogen peroxide in the ultrasonic treatment device. Preferably, the pipe can be distributed in a serpentine shape, thereby achieving control of the length change of the pipe in a limited space without additionally expanding the space occupied by the ultrasonic generator.

[0039] Furthermore, the membrane filter selected in the filtration stage of the present invention is a filter membrane with a special membrane material of polytetrafluoroethylene (PVDF). By utilizing the polarity and surface tension of the filter membrane of this material, as well as the selection of the filtration accuracy of the filter membrane, the insoluble matter precipitated due to cooling in the previous stage can be completely filtered down, and the ultrasonic assisted filtration of the three-stage filter element can effectively reduce the permeability of organic matter, achieve the purpose of nano-level purification, and greatly reduce the organic matter content in the treated hydrogen peroxide. In addition, in some optional embodiments, the selected filter membrane can also be rinsed with ultrapure water before use, which can minimize the dissolution of the filter element, thereby making the filtration more effective.

[0040] The method of the invention can not only meet the strict quality requirements of ultra-high purity hydrogen peroxide products, but also adapt to the characteristics of hydrogen peroxide, will not cause production safety hazards, and has the advantages of short separation time, high efficiency, easy operation, etc.

[0041] The above scheme is further described below in conjunction with specific embodiments; it should be understood that these embodiments are used to illustrate the basic principles, main features and advantages of the present invention, and the present invention is not limited to the scope of the following embodiments; the implementation conditions adopted in the embodiments can be further adjusted according to specific requirements, and the implementation conditions not specified are usually the conditions in conventional experiments.

[0042] Unless otherwise specified in the following examples, all raw materials can be purchased from commercial sources or prepared by conventional methods in the art.

[0043] In the following description, unless otherwise specified, "wt %" refers to concentration in weight percent.

[0044] Example 1

[0045] This example provides a method for purifying hydrogen peroxide, which adopts Figure 1 The process flow shown includes the following steps performed sequentially and continuously:

[0046] (1) adjusting the concentration of industrial hydrogen peroxide (50 wt % from Arkema Chemicals Co., Ltd.) to about 30 wt %, and controlling the feed temperature of hydrogen peroxide to 2.5 ± 1 °C;

[0047] (2) the hydrogen peroxide treated in step (1) is sequentially introduced into a first-stage ultrasonic treatment device at a flow rate of 100 L / h, the hydrogen peroxide flowing out of the pipeline enters a first-stage membrane filtration device (the filter element is a MILLI microporous filter membrane with a pore size of 0.05 μm, and the filter element material is polytetrafluoroethylene (PVDF)), then enters a second-stage ultrasonic treatment device, the hydrogen peroxide flowing out of the pipeline enters a second-stage membrane filtration device (the filter element is a column ultrafiltration membrane (molecular weight cutoff 1000D) with a pore size of 0.01 μm, and the filter element material is polytetrafluoroethylene (PVDF)), and finally enters a third-stage ultrasonic treatment device, the hydrogen peroxide flowing out of the pipeline enters a third-stage membrane filtration device (the filter element is an American Hyde reverse osmosis (RO) membrane with a pore size of 1 nm, and the filter element material is polytetrafluoroethylene (PVDF)), to obtain hydrogen peroxide with organic matter removed;

[0048] Among them, the filtration pressure is: 0.5MPa for the first-stage membrane filtration device, 0.5MPa for the first-stage membrane filtration device, and 0.5MPa for the first-stage membrane filtration device; the residence time of the first-stage ultrasonic treatment device, the residence time of the second-stage ultrasonic treatment device, and the residence time of the third-stage ultrasonic treatment device are controlled to be 10min, 20min, and 30min respectively;

[0049] The operating frequency of the ultrasonic generator of the ultrasonic treatment device is 25kHz;

[0050] The specific process of the purification method is controlled to be carried out at an ambient temperature of 20±5°C;

[0051] The test results of organic impurity content in the purified hydrogen peroxide are shown in Table 1.

[0052] Example 2

[0053] This example provides a method for purifying hydrogen peroxide, which is basically the same as Example 1, except that:

[0054] In step (1), the concentration of industrial hydrogen peroxide (50 wt % from Arkema Chemicals Co., Ltd.) was adjusted to 35 wt %;

[0055] In step (2), the hydrogen peroxide treated in step (1) is sequentially introduced into a primary ultrasonic treatment device at a flow rate of 150 L / h.

[0056] The test results of organic impurity content in the purified hydrogen peroxide are shown in Table 1.

[0057] Example 3

[0058] This example provides a method for purifying hydrogen peroxide, which is basically the same as Example 1, except that:

[0059] In step (1), the concentration of industrial hydrogen peroxide (50 wt % from Arkema Chemicals Co., Ltd.) was adjusted to 40 wt %;

[0060] In step (2), the hydrogen peroxide treated in step (1) is sequentially introduced into a primary ultrasonic treatment device at a flow rate of 200 L / h.

[0061] The test results of organic impurity content in the purified hydrogen peroxide are shown in Table 1.

[0062] Example 4

[0063] This example provides a method for purifying hydrogen peroxide, which is basically the same as Example 1, except that the residence time of the first-stage ultrasonic treatment device, the residence time of the second-stage ultrasonic treatment device, and the residence time of the third-stage ultrasonic treatment device are controlled to be 10 minutes, 25 minutes, and 35 minutes, respectively.

[0064] Comparative Example 1

[0065] This example provides a method for purifying hydrogen peroxide, comprising the following steps performed sequentially and continuously:

[0066] (1) adjusting the concentration of industrial hydrogen peroxide (50 wt % from Arkema Chemicals Co., Ltd.) to about 30 wt %, and controlling the feed temperature of hydrogen peroxide to 2.5 ± 1 °C;

[0067] (2) The treated hydrogen peroxide was passed through macroporous adsorption resins (A and B series macroporous adsorption resins of Anhui Bengbu Tianxing Resin Company) at a flow rate of 200 L / h to obtain hydrogen peroxide with organic matter removed. The results of the detection of organic impurity content in the purified hydrogen peroxide are shown in Table 1.

[0068] Comparative Example 2

[0069] This example provides a method for purifying hydrogen peroxide, which is basically the same as Example 1, except that the three-stage ultrasonic treatment device is omitted, and the hydrogen peroxide is sequentially passed through three-stage membrane filtration devices. The test results of the organic impurity content of the purified hydrogen peroxide are shown in Table 1.

[0070] Comparative Example 3

[0071] This example provides a method for purifying hydrogen peroxide, which is basically the same as Example 1, except that the residence time in the three-stage ultrasonic treatment device is controlled to be the same. The test results of the organic impurity content of the purified hydrogen peroxide are shown in Table 1.

[0072] Table 1 Organic impurity content in hydrogen peroxide after removal of organic matter in Examples 1-4 and Comparative Examples 1-3

[0073]

[0074] As can be seen from the above, compared with Example 1, the removal of organic matter in Comparative Examples 1-3 is significantly reduced. Although the removal effect of organic matter in Comparative Example 1 is relatively good, it uses conventional macroporous adsorption resin, which determines the high frequency of resin desorption and regeneration, making the cost higher; the removal effect of organic matter in Comparative Example 2 is the worst, indicating that ultrasonic treatment plays an important role in the method of the present invention. Comparative Example 3 makes the residence time in different ultrasonic treatment devices, which changes with the coordination of different membrane filtration devices, and it is difficult to maximize the removal of organic matter, resulting in the final high content of organic matter in hydrogen peroxide. The present invention adopts a method of using ultra-low temperature and ultrasonic oscillation to assist membrane filtration to separate organic matter in hydrogen peroxide, further combined with multi-stage sequential processing, and controlling the residence time of ultrasonic oscillation in each stage and using membrane filtration multi-stage aperture coordination to achieve efficient removal of organic matter in hydrogen peroxide, which can make the organic matter content basically below 10ppb, or even below 5ppb.

[0075] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

[0076] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

Claims

1. A method for purifying hydrogen peroxide, using industrial grade hydrogen peroxide as raw material, characterized in that: The purification method comprises: The mass percentage concentration of industrial-grade hydrogen peroxide is adjusted to 30%-40%, and the system feed temperature is controlled to be 0-5°C, and then the treated hydrogen peroxide is passed through n organic treatment units arranged in series, where n is greater than or equal to 2; Each of the organic matter treatment units independently comprises an ultrasonic treatment device and a membrane filtration device which are connected in sequence. In each of the organic matter treatment units, hydrogen peroxide is sequentially subjected to oscillation treatment by the ultrasonic treatment device and filtration treatment by the membrane filtration device; Controlling the residence time of hydrogen peroxide in the ultrasonic treatment device included in the organic matter treatment unit of the next stage to be greater than the residence time in the ultrasonic treatment device included in the organic matter treatment unit of the previous stage; Controlling the pore size of the filter element of the membrane filtration device included in the organic matter treatment unit of the next stage to be smaller than the pore size of the filter element of the membrane filtration device included in the organic matter treatment unit of the previous stage; Wherein, when n is 3, the treated hydrogen peroxide is sequentially passed through a first-stage ultrasonic treatment device, a first-stage membrane filtration device, a second-stage ultrasonic treatment device, a second-stage membrane filtration device, a third-stage ultrasonic treatment device, and a third-stage membrane filtration device arranged in series; Control the residence time of the first-stage ultrasonic treatment device, the residence time of the second-stage ultrasonic treatment device, and the residence time of the third-stage ultrasonic treatment device to be 5-15 minutes, 15-25 minutes, and 25-35 minutes respectively; The pore sizes of the filter element of the primary membrane filtration device, the secondary membrane filtration device, and the pore sizes of the filter element of the tertiary membrane filtration device are controlled to be 0.04-0.06 μm, 0.005-0.015 μm, and 0.5-10 nm, respectively.

2. The method for purifying hydrogen peroxide according to claim 1, characterized in that: n is 3, 4 or 5.

3. The method for purifying hydrogen peroxide according to claim 1, characterized in that: The operating frequency of the ultrasonic processing device is 25-40kHz.

4. The method for purifying hydrogen peroxide according to claim 1, characterized in that: The residence time of hydrogen peroxide in the ultrasonic treatment device included in the organic matter treatment unit of the next stage is controlled to be 1.2-3 times of the residence time in the ultrasonic treatment device included in the organic matter treatment unit of the previous stage.

5. The method for purifying hydrogen peroxide according to claim 1, characterized in that: The pore size of the filter element of the membrane filtration device included in the organic matter treatment unit of the next stage is controlled to be 0.05-0.8 times the pore size of the filter element of the membrane filtration device included in the organic matter treatment unit of the previous stage.

6. The method for purifying hydrogen peroxide according to claim 1, characterized in that: The filter element of the membrane filtration device is made of polytetrafluoroethylene.

7. The method for purifying hydrogen peroxide according to claim 1, characterized in that: The filtration pressure of the membrane filtration device is 0.5-0.8MPa.

8. The method for purifying hydrogen peroxide according to claim 1, characterized in that: The ultrasonic treatment device comprises an ultrasonic generator and a pipeline arranged in the ultrasonic generator. The length of the pipeline is controlled to control the residence time of hydrogen peroxide in the ultrasonic treatment device.

9. The method for purifying hydrogen peroxide according to claim 1, characterized in that: The flow rate of the treated hydrogen peroxide in the organic matter treatment unit is 100L / h to 200L / h; and / or the specific process of the purification method is controlled to be carried out at an ambient temperature of less than or equal to 25°C.

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