Purification method for removing metal ions and anions in hydrogen peroxide

Abstract

The invention provides a purification method for powerfully removing metal ions and anions in hydrogen peroxide, which comprises the following steps of: cooling hydrogen peroxide at normal temperature to 0-20 DEG C, and sequentially passing the cooled hydrogen peroxide through an anion exchange resin tower, a cation exchange resin tower and a mixed ion exchange resin column at the flow rate of 0.3-1.0 L / s to remove metal ions and anions, according to the method, high-flow hydrogen peroxide can be introduced into the resin tower, the actual conditions of industrial production are better matched, the problem that data in the prior art can only be used for processing small flow is solved, and finally electronic-grade hydrogen peroxide with single metal ions smaller than or equal to 5 ppt and anions smaller than or equal to 2 ppb is obtained. The influence of counter ions is eliminated by screening the models of anion / cation resins and determining the mixing ratio, the stability of a mixed ion exchange resin bed layer is ensured by uniformly mixing the anion / cation resins, the purification process is green and safe, waste liquid, waste gas and waste solids are not generated, and meanwhile, the cleanliness and the purification effect of the resins are also improved.

Description

Technical Field

[0001] The invention relates to the field of purification of hydrogen peroxide, and in particular to a purification method for effectively removing metal ions and anions from hydrogen peroxide. Background Art

[0002] With the rapid development of the semiconductor industry, electronic grade hydrogen peroxide (H 2 O 2 ) is a key cleaning and oxidizing agent, playing a vital role in processes such as integrated circuit manufacturing and chip packaging. Compared with industrial-grade hydrogen peroxide, electronic-grade hydrogen peroxide has stricter requirements on the content of impurities, especially metal ions and anion impurities, which may cause device performance degradation, failure or affect product quality. Therefore, developing an efficient purification method to remove these impurities in hydrogen peroxide has become the key to improving the quality of electronic-grade hydrogen peroxide.

[0003] Traditional impurity removal methods such as precipitation and membrane separation, although they have removal capabilities to some extent, have significant deficiencies in processing capacity, cost and reproducibility. In recent years, ion exchange technology has attracted attention due to its high efficiency and strong selectivity. However, it is difficult for a single anion exchange resin tower and a cation exchange resin tower to reduce trace inorganic ions and metal ion impurities in hydrogen peroxide to a low level, and affected by the structure and manufacturing process of the resin itself, anion exchange resins often cause certain metal dissolution when purifying hydrogen peroxide. When alkaline anion exchange resins come into contact with hydrogen peroxide, they will accelerate the decomposition of hydrogen peroxide to produce some bubbles and heat. If the heat is not removed in time, heat will accumulate in the resin column, the temperature will rise rapidly, and a rapid chain reaction will be formed, resulting in the instantaneous decomposition of hydrogen peroxide in the resin column. In addition, cation exchange resins will cause the dissolution of sulfate under the strong oxidation of hydrogen peroxide. Generally, common cation exchange resins are sodium or hydrogen types. The existence of these problems makes it difficult for anion and cation exchange resins to meet the requirements for the removal of trace anions and metal ions in hydrogen peroxide when used alone.

[0004] For example, the patent with announcement number CN117819485A discloses a method for removing trace metal ions in hydrogen peroxide. The mixed ion exchange resin prepared in the patent is affected by counter ions, and the hydroxide-type strong alkaline anion exchange resin has certain safety hazards if it is not transformed. In addition, the resin is not screened before mixing, and the purification effect of hydrogen peroxide is poor. Summary of the invention

[0005] The purpose of the present invention is to overcome the above-mentioned shortcomings and provide a purification method for effectively removing metal ions and anions in hydrogen peroxide. The method uses industrial-grade hydrogen peroxide as a raw material, first cools the hydrogen peroxide at room temperature to 0-20°C, and then passes the cooled hydrogen peroxide through an anion exchange resin tower, a cation exchange resin tower, and a mixed ion exchange resin column in a bottom-in-top-out or top-in-bottom-out manner at a flow rate of 0.3-1.0 L / s to remove metal ions and anions. A large flow of hydrogen peroxide can be introduced into the resin tower, which is more compatible with the actual conditions of industrial production and overcomes the shortcomings of the prior art. Technical data can only handle the problem of small flow, and finally obtain electronic grade hydrogen peroxide with single metal ion ≤10ppt and anion ≤5ppb, and further preferably obtain electronic grade hydrogen peroxide with single metal ion ≤5ppt and anion ≤2ppb; effectively improve the reaction between hydrogen peroxide and resin, eliminate the influence of counter ions by screening the type and mixing ratio of anion / cation resin, and the uniform mixing of anion and cation resin ensures the stability of mixed ion exchange resin, and the purification process is green and safe, and will not produce waste liquid, waste gas and waste solid, and at the same time improve the cleanliness of the resin itself and the purification effect. In addition, the cation exchange resin can be recycled after being treated with a regeneration agent, and still maintains a good purification effect on hydrogen peroxide, saving a certain amount of cost.

[0006] In view of the above technical solution, the present invention provides a purification method for removing metal ions and anions in hydrogen peroxide, comprising the following steps: (1) Anion exchange resin pretreatment: After the anion exchange resin is cleaned, carbon dioxide is introduced and NaHCO is added. 3 Or join NH 4 HCO 3 The anion exchange resin is transformed by any one of the reagents to obtain a pretreated anion exchange resin; (2) Fine treatment of cation exchange resin: After the cation exchange resin is cleaned, acid is added and ultrasonic impregnation is performed to obtain a finely treated cation exchange resin; (3) mixing the anion exchange resin and cation exchange resin treated in steps (1) and (2) to prepare a mixed ion exchange resin, which is then loaded into an ion exchange resin tower; (4) The hydrogen peroxide raw material is passed into a mixed ion exchange resin tower to obtain hydrogen peroxide with cations and anions removed.

[0007] The anion exchange resin described in step (1) is selected from UPW 550B of Xi'an Lanxiao, SA550-6 of Xi'an Lanxiao, HPR550 of Rohm and Haas, NRW505 of Purolite, or SQ-708EC of Jiangsu Suqing.

[0008] In the step (1), during the transformation process, an anion exchange resin is loaded into a resin tower, carbon dioxide gas is introduced, and then maintained under pressure for 1-2 days.

[0009] Alternatively, load the anion exchange resin into the resin tower and add NaHCO 3 solution, or add NH 4 HCO 3 Solution, soak for 1-2 days to achieve the transformation to anion exchange resin.

[0010] It is understood by those skilled in the art that the purity of carbon dioxide gas is greater than 99.9%; NaHCO 3 Solution or NH 4 HCO 3 The purity of the solution is greater than 99.9%.

[0011] The cation exchange resin described in step (2) is selected from SC980N of Xi'an Lanxiao, ZGC650G of Zhejiang Zhengguang, HPR650 of Rohm and Haas, or SQ-608EC of Jiangsu Suqing.

[0012] The acid is selected from hydrochloric acid, sulfuric acid and nitric acid, and the concentration is 1% to 90%.

[0013] It is understandable to those skilled in the art that the purity of hydrochloric acid, sulfuric acid and nitric acid is greater than 99.9%.

[0014] In step (3), the total mass ratio of anion exchange resin to cation exchange resin is (0.5-3):1.

[0015] The hydrogen peroxide is selected from industrial grade or above purity, the concentration of hydrogen peroxide raw material is 20-60%, and the hydrogen peroxide is cooled to 0-20°C.

[0016] In the step (4), the hydrogen peroxide is introduced into the mixed ion exchange resin tower by using a dynamic diaphragm pump, and the gas introduced by the dynamic diaphragm pump is one of hydrogen, oxygen and nitrogen.

[0017] It is understandable to those skilled in the art that the purity of hydrogen, oxygen and nitrogen is greater than 99.9%.

[0018] The flow rate of the hydrogen peroxide raw material is controlled by a pneumatic diaphragm pump to be 0.3-1.0 L / s. In some preferred cases, the flow rate is 0.5-1.0 L / s.

[0019] The pneumatic diaphragm pump is used to pass hydrogen peroxide into the resin tower for experiment. The gas must be clean and safe and have no effect on the quality of hydrogen peroxide. The present invention uses hydrogen, oxygen or nitrogen.

[0020] In some cases, before the hydrogen peroxide raw material is passed into the mixed ion exchange resin column in step (4), an anion exchange resin is first used to pass through the column, and the anion exchange resin is selected from Cl - OH - Type or HCO 3 - A combination of one or more types.

[0021] In other cases, before the hydrogen peroxide raw material in step (4) is passed into the mixed ion exchange resin tower, it is first passed through an anion exchange resin and a cation exchange resin in sequence, and the anion exchange resin is selected from a combination of one or more of Cl-, OH- or HCO3- type.

[0022] The cation exchange resin is selected from a combination of one or more of Na+ or H+ types.

[0023] In the above technical solution, the anion exchange resin is selected from UPW 550B of Xi'an Lanxiao or SA550-6 of Xi'an Lanxiao or HPR550 of Rohm and Haas or NRW505 of Purolite or SQ-708EC of Jiangsu Suqing; The cation exchange resin is selected from SC980N of Xi'an Lanxiao, ZGC650G of Zhejiang Zhengguang, HPR650 of Rohm and Haas, or SQ-608EC of Jiangsu Suqing.

[0024] The feeding and discharging methods of the anion exchange resin tower, cation exchange resin tower and mixed bed resin tower are one of top-in and bottom-out or bottom-in and top-out.

[0025] The anionic resin in the mixed ion exchange resin is transformed from a strongly alkaline environment to a neutral environment, which ensures the safety of hydrogen peroxide and does not produce waste liquid, waste gas and waste solid; the cationic resin in the mixed resin is improved after fine treatment to improve the purity of the resin and the purification effect of the resin; by screening the models and mixing ratios of anionic / cationic resins, the optimal model and ratio are finally obtained, the resins are mixed evenly without agglomeration, the influence of counter ions is eliminated, and the best purification effect for hydrogen peroxide is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0027] In order to more clearly understand the technical problems, technical solutions and advantages solved by the present invention, the purification method for effectively removing metal ions and anions from hydrogen peroxide of the present invention is further described in detail through specific embodiments below: Example 1 (1) Anion exchange resin pretreatment: Use ultrapure water to clean the anion exchange resin (SA550-6) until the conductivity of the eluate is less than or equal to the conductivity of ultrapure water. Then, introduce carbon dioxide from the top of the resin tower. When the pressure in the tower reaches the set value, the ultrapure water in the resin tower is circulated in a bottom-in-top-out manner by a pneumatic diaphragm pump to keep the pressure in the tower unchanged.

[0028] (2) Fine treatment of cation exchange resin: Use ultrapure water to clean the cation exchange resin (SC980N) until the conductivity of the eluate is less than or equal to the conductivity of ultrapure water, then add dilute sulfuric acid with a concentration of 6.5%, stir and ultrasonicate evenly, and then clean the resin with ultrapure water until the cleaning solution is neutral.

[0029] (3) Loading of mixed bed resin into a tower: The anion / cation exchange resins pretreated in steps (1) and (2) are mixed at an ion ratio of 1.5:1 to prepare a mixed ion exchange resin, which is then loaded into an ion exchange resin tower.

[0030] (4) Loading of anion exchange resin into the tower: Use ultrapure water to clean the anion exchange resin (NRW505) until the conductivity of the eluate is less than or equal to the conductivity of ultrapure water, and then load it into the ion exchange resin tower.

[0031] (5) Loading of cation exchange resin into the tower: Use ultrapure water to clean the cation exchange resin (HPR650) until the conductivity of the eluate is less than or equal to the conductivity of ultrapure water, and then load it into the ion exchange resin tower.

[0032] (6) Using ultrapure water, backwash the mixed ion exchange resin, anion exchange resin, and cation exchange resin towers in steps (3), (4), and (5), respectively, until the conductivity of the eluate is less than or equal to the conductivity of the ultrapure water.

[0033] (7) Pre-cool the industrial-grade hydrogen peroxide raw material to 10°C through a heat exchanger.

[0034] (8) The hydrogen peroxide raw material treated in step (7) is sequentially introduced into an anion exchange resin tower, a cation exchange resin tower and a mixed ion exchange resin tower (upper inlet and lower outlet: mixed / anion exchange resin; lower inlet and upper outlet: cation exchange resin) through a pneumatic diaphragm pump at a flow rate of 0.5 L / s to finally obtain electronic grade hydrogen peroxide with a single metal ion of ≤5 ppt and an anion of ≤2 ppb.

[0035] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0036] Example 2 The method and steps are the same as those in Example 1, except that after the experiment in step (1), the cation exchange resin (SC980N) is passed through dilute sulfuric acid with a concentration of 5% to elute the metal ions in the resin, and then the resin is washed with ultrapure water until the washing liquid is neutral.

[0037] Example 3 The method and steps are the same as those in Example 1, except that in step (3), the ion ratio of the anion and cation exchange resins after treatment is adjusted to 2:1.

[0038] Example 4 The method and steps are the same as those in Example 1, except that in step (4), the model of the anion exchange resin after treatment is adjusted to UPW550B.

[0039] Example 5 The method and steps are the same as those in Example 1, except that the addition of the anion exchange resin in step (4) is omitted.

[0040] Example 6 The method and steps are the same as those in Example 1, except that in step (5), the model of the cation exchange resin after treatment is adjusted to SQ-608EC.

[0041] Example 7 The method and steps are the same as those in Example 1, except that the addition of the cation exchange resin in step (5) is omitted.

[0042] Example 8 The method and steps are the same as those in Example 1, except that in step (1), the model of the cation exchange resin after treatment is adjusted to HPR650.

[0043] Example 9 The method and steps are the same as those in Example 1, and the resin models in steps (1), (2), (4), and (5) are respectively changed to UPW550B, ZGC650G, SQ-708EC, and SC980N.

[0044] Example 10 The method and steps are the same as those in Example 3, except that in step (7), the hydrogen peroxide raw material is pre-cooled to 5°C through a heat exchanger.

[0045] Comparative Example 1 The method and steps are the same as those in Example 1, except that the anion exchange resin models in steps (1) and (4) are respectively changed to UPW550B and Amberjet UP4000.

[0046] Comparative Example 2 The method and steps are the same as those in Example 1, except that the cation exchange resin models in steps (2) and (5) are changed to ZGA351 and NRW650.

[0047] Comparative Example 3 (1) Pretreatment and tower loading of anion exchange resin: Use ultrapure water to clean the anion exchange resin (SA550-6) until the conductivity of the eluate is less than or equal to the conductivity of ultrapure water. Then, introduce carbon dioxide from the top of the resin tower. When the pressure in the tower reaches the set value, the ultrapure water in the resin tower is circulated in a bottom-in-top-out manner by a pneumatic diaphragm pump to keep the pressure in the tower unchanged.

[0048] (2) Fine treatment of cation exchange resin: Use ultrapure water to clean the cation exchange resin (SC980N) until the conductivity of the eluate is less than or equal to the conductivity of ultrapure water, then add dilute sulfuric acid with a concentration of 6.5%, stir and ultrasonicate evenly, wash the resin with ultrapure water until the cleaning solution is neutral, and then load it into the ion exchange resin tower.

[0049] (3) Loading of anion exchange resin into the tower: Use ultrapure water to clean the anion exchange resin (NRW505) until the conductivity of the eluate is less than or equal to the conductivity of ultrapure water, and then load it into the ion exchange resin tower.

[0050] (4) Loading of cation exchange resin into the tower: Use ultrapure water to clean the cation exchange resin (HPR650) until the conductivity of the eluate is less than or equal to the conductivity of ultrapure water, and then load it into the ion exchange resin tower.

[0051] (5) Backwash the anion exchange resin tower, cation exchange resin tower, anion exchange resin tower, and cation exchange resin tower in steps (3), (4), (1), and (2) with ultrapure water until the conductivity of the eluate is less than or equal to the conductivity of the ultrapure water.

[0052] (7) Pre-cool the industrial-grade hydrogen peroxide raw material to 10°C through a heat exchanger.

[0053] (8) The hydrogen peroxide raw material treated in step (7) is sequentially introduced into an anion exchange resin tower (NRW505), a cation exchange resin tower (HPR650), an anion exchange resin tower (SA550-6), and a cation exchange resin tower (SC980N) (upper inlet and lower outlet: anion exchange resin; lower inlet and upper outlet: cation exchange resin) through a pneumatic diaphragm pump at a flow rate of 0.3 L / s.

[0054] Comparative Example 4 (1) Loading of anion exchange resin into the tower: Use ultrapure water to clean the anion exchange resin (NRW505) until the conductivity of the eluate is less than or equal to the conductivity of ultrapure water, and then load it into the ion exchange resin tower.

[0055] (2) Loading of cation exchange resin into the tower: Use ultrapure water to clean the cation exchange resin (HPR650) until the conductivity of the eluate is less than or equal to the conductivity of ultrapure water, and then load it into the ion exchange resin tower.

[0056] (3) Using ultrapure water, backwash the mixed ion exchange resin, anion exchange resin, and cation exchange resin towers in steps (3), (4), and (5), respectively, until the conductivity of the eluate is less than or equal to the conductivity of the ultrapure water.

[0057] (4) Pre-cool the industrial-grade hydrogen peroxide raw material to 10°C through a heat exchanger.

[0058] (5) The hydrogen peroxide raw material treated in step (4) is sequentially introduced into an anion exchange resin tower and a cation exchange resin tower (upper inlet and lower outlet: anion exchange resin; lower inlet and upper outlet: cation exchange resin) through a pneumatic diaphragm pump at a flow rate of 0.3 L / s.

[0059] Table 1 Metal ion content in purified hydrogen peroxide of Examples 1-10 and Comparative Examples 1-4

[0060] Table 2 Anion content in purified hydrogen peroxide of Examples 1-10 and Comparative Examples 1-5

[0061] As can be seen from Table 1 and Table 2, the mixed ion exchange resin prepared by the transformed anion exchange resin and the finely treated cation exchange resin can improve the purity of the resin, which is more conducive to removing anions and metal ions in hydrogen peroxide; when the ratio of anion / cation exchange resin is 1.5:1, and the screened anion / cation exchange resin is selected, the ion exchange process between the resin and hydrogen peroxide is more thorough, and the bed stability of the resin is guaranteed. After continuous passing through the anion / cation / mixed three-stage ion exchange resin, the purification effect of hydrogen peroxide is the best, and ultra-high purity electronic grade hydrogen peroxide with single metal ions ≤5ppt and anions ≤2ppb can be obtained. In addition, the elution treatment of the used cation exchange resin in Example 2 has almost no effect on the purification effect of hydrogen peroxide, and the recycling of the resin can save a certain economic cost.

[0062] In Comparative Examples 1 and 2, the purification effect of the disclosed anion / cation exchange resin model on hydrogen peroxide is worse than the resin selected by this patent, and a large flow of hydrogen peroxide can be introduced into the resin tower, which is more compatible with the actual conditions of industrial production. In addition, the anion / cation exchange resin model in the disclosed patent is agglomerated when preparing the mixed ion exchange resin, and the uneven bed layer leads to poor effect. In Comparative Example 3, the use of the anion or cation resin in the mixed ion exchange resin in the tower alone will affect the final purification result of hydrogen peroxide. This patent considers the density, particle size, ion exchange capacity and other parameters of the anion / cation resin to screen the appropriate resin model to prepare the mixed ion exchange resin, which can eliminate the influence of counterions and show the best purification effect. Comparative Example 4 is the same as Comparative Example 3, but the effect is poor without the mixed ion exchange resin in series.

[0063] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A purification method for removing metal ions and anions from hydrogen peroxide, characterized in that: The following steps are involved: (1) Anion exchange resin pretreatment: After the anion exchange resin is cleaned, it is transformed by introducing carbon dioxide, adding NaHCO3 or adding NH4HCO3 reagent to obtain a pretreated anion exchange resin; (2) Fine treatment of cation exchange resin: After the cation exchange resin is cleaned, acid is added and ultrasonic impregnation is performed to obtain a finely treated cation exchange resin; (3) mixing the anion exchange resin and cation exchange resin treated in steps (1) and (2) to prepare a mixed ion exchange resin, which is then loaded into an ion exchange resin tower; (4) The hydrogen peroxide raw material is passed into a mixed ion exchange resin tower to obtain hydrogen peroxide with cations and anions removed.

2. The method for removing metal ions and anions from hydrogen peroxide according to claim 1, characterized in that: The anion exchange resin described in step (1) is selected from UPW 550B of Xi'an Lanxiao, SA550-6 of Xi'an Lanxiao, HPR550 of Rohm and Haas, NRW505 of Purolite, or SQ-708EC of Jiangsu Suqing.

3. The method for purifying hydrogen peroxide for removing metal ions and anions according to claim 1, characterized in that: In the step (1), during the transformation process, an anion exchange resin is loaded into a resin tower, carbon dioxide gas is introduced, and then maintained under pressure for 1-2 days; Alternatively, the anion exchange resin is loaded into a resin tower, and after adding NaHCO3 solution or NH4HCO3 solution, it is immersed for 1-2 days to achieve the transformation of the anion exchange resin.

4. The method for purifying hydrogen peroxide for removing metal ions and anions according to claim 1, characterized in that: The cation exchange resin described in step (2) is selected from SC980N of Xi'an Lanxiao, ZGC650G of Zhejiang Zhengguang, HPR650 of Rohm and Haas, or SQ-608EC of Jiangsu Suqing.

5. The method for purifying hydrogen peroxide for removing metal ions and anions according to claim 1, characterized in that: The acid is selected from hydrochloric acid, sulfuric acid and nitric acid, and the concentration is 1% to 90%.

6. The method for removing metal ions and anions from hydrogen peroxide according to claim 1, characterized in that: In step (3), the total mass ratio of anion exchange resin to cation exchange resin is (0.5-3):

1.

7. The method for purifying hydrogen peroxide for removing metal ions and anions according to claim 1, characterized in that: The hydrogen peroxide is selected from industrial grade or above purity, the concentration of hydrogen peroxide raw material is 20-60%, and the hydrogen peroxide is cooled to 0-20°C.

8. The method for purifying hydrogen peroxide for removing metal ions and anions according to claim 7, characterized in that: In the step (4), the hydrogen peroxide is introduced into the mixed ion exchange resin tower by using a pneumatic diaphragm pump, and the gas introduced by the pneumatic diaphragm pump is one of hydrogen, oxygen and nitrogen; A pneumatic diaphragm pump is used to control the flow rate of the hydrogen peroxide raw material to 10~50 BV / h.

9. The method for purifying hydrogen peroxide for removing metal ions and anions according to claim 1, characterized in that: In the step (4), before the hydrogen peroxide raw material is passed into the mixed ion exchange resin tower, an anion exchange resin is first used to pass through the column, and the anion exchange resin is selected from Cl - OH - Type or HCO3 - A combination of one or more types.

10. The method for purifying hydrogen peroxide for removing metal ions and anions according to claim 1, characterized in that: In the step (4), before the hydrogen peroxide raw material is passed into the mixed ion exchange resin tower, an anion exchange resin and a cation exchange resin are first used to pass through the column in sequence, and the anion exchange resin is selected from Cl - OH - Type or HCO3 - A combination of one or more types; The cation exchange resin is selected from Na + or H + A combination of one or more types.

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