阅读说明：本技术 一种低温去除双氧水中toc的提纯方法 (Purification method for removing TOC in hydrogen peroxide at low temperature ) 是由 林益兴 王琴 于 2021-01-04 设计创作，主要内容包括：本发明公开了一种低温去除双氧水中TOC的提纯方法,属于精细化工中化学品提纯技术领域。该方法主要包括依次进行的冷却阶段和过滤阶段,其中冷却阶段为将工业级双氧水冷却至0-8℃,其中过滤阶段为将经冷却后的双氧水采用膜过滤器进行过滤去除TOC。该方法能够使工业级双氧水在不使用树脂吸附的情况下直接低温去除其中TOC后,再进行阳离子的去除和阴离子的去除,保证进入后续去除阴阳离子树脂塔内的双氧水有较高的纯度,降低阴阳离子树脂塔的负荷,从而能够提高后续树脂塔的使用寿命。(The invention discloses a purification method for removing TOC in hydrogen peroxide at low temperature, belonging to the technical field of purification of chemicals in fine chemical engineering. The method mainly comprises a cooling stage and a filtering stage which are sequentially carried out, wherein the cooling stage is to cool industrial-grade hydrogen peroxide to 0-8 ℃, and the filtering stage is to filter the cooled hydrogen peroxide by a membrane filter to remove TOC. The method can remove TOC in industrial-grade hydrogen peroxide at low temperature directly without resin adsorption, and then remove cations and anions, so that hydrogen peroxide entering a subsequent anion and cation resin removal tower has high purity, the load of the anion and cation resin removal tower is reduced, and the service life of the subsequent resin removal tower can be prolonged.)

1. The purification method for removing TOC in hydrogen peroxide at low temperature is characterized by mainly comprising a cooling stage and a filtering stage which are sequentially carried out, wherein the cooling stage is to cool industrial-grade hydrogen peroxide to 0-8 ℃, and the filtering stage is to filter the cooled hydrogen peroxide by a membrane filter to remove TOC.

2. The purification method for removing TOC in hydrogen peroxide at low temperature according to claim 1, characterized in that: in the cooling stage, industrial-grade hydrogen peroxide is cooled to 4-8 ℃.

3. The purification method for removing TOC in hydrogen peroxide at low temperature according to claim 2, characterized in that: and in the cooling stage, cooling industrial-grade hydrogen peroxide to 8 ℃.

4. The purification method for removing TOC in hydrogen peroxide at low temperature according to claim 1, characterized in that: the membrane filter adopted in the filtering stage is a membrane filter using a polyethersulfone membrane folding filter element, and the filtering precision of the polyethersulfone membrane folding filter element is 0.05-0.1 mu m.

5. The purification method for removing TOC in hydrogen peroxide at low temperature according to claim 4, characterized in that: the filtering precision of the polyethersulfone membrane folding filter element is 0.1 mu m.

6. The purification method for removing TOC in hydrogen peroxide at low temperature according to claim 4, characterized in that: the filtering precision of the polyethersulfone membrane folding filter element is 0.05 mu m.

7. The purification method for removing TOC in hydrogen peroxide at low temperature according to claim 4, characterized in that: the polyethersulfone membrane folding filter element is rinsed by ultrapure water before use.

8. The purification method for removing TOC in hydrogen peroxide at low temperature according to claim 1, characterized in that: the TOC content of the industrial-grade hydrogen peroxide to be treated is below 2500 ppm.

Technical Field

The invention relates to a method for purifying hydrogen peroxide, in particular to a method for purifying hydrogen peroxide by removing TOC at low temperature, belonging to the technical field of purification of chemicals in fine chemical engineering.

Background

Hydrogen peroxide is an important processing chemical in the semiconductor manufacturing industry, and is usually used in the cleaning process of large-scale integrated circuits after being compounded with sulfuric acid, ammonia water, hydrochloric acid and the like. When applied to this process, these processing aids or reagents, particularly hydrogen peroxide, are required to be of extremely high purity, including having extremely low organic matter (TOC), extremely low metal cation content and various anion content, i.e., ultra-clean, high purity, electronic grade hydrogen peroxide is required. In addition, in addition to the requirement of using the ultra-clean and high-purity hydrogen peroxide in the electronic field, hydrogen peroxide is also required to have higher purity in the field of common chemical reagents and in the food industry.

At present, almost all the production of hydrogen peroxide at home and abroad adopts an anthraquinone method, which mainly adopts alkyl anthraquinone to carry out hydrogenation, then the produced alkyl anthraquinone hydroxide is reoxidized to produce alkyl anthraquinone and hydrogen peroxide, and then the hydrogen peroxide is extracted and separated to obtain industrial grade hydrogen peroxide. The industrial grade hydrogen peroxide water inevitably contains various organic impurities, metal impurities and non-metal impurities due to the characteristics of the production process, wherein the organic impurities mainly come from introduced working solvents, soluble degradation products and the like generated in the production process, and mainly contain heavy aromatic hydrocarbon, trioctyl phosphate, anthraquinone and derivatives thereof, and the content of the organic impurities is usually more than 100ppm calculated by Total Organic Carbon (TOC). The presence of the organic impurities causes the appearance of the industrial grade hydrogen peroxide to be light yellow and have special odor, which causes the application of the product to be obviously limited especially in the aforementioned fields requiring the use of ultra-clean high-purity hydrogen peroxide. Therefore, the industrial-grade hydrogen peroxide prepared and formed needs to be purified, and the mass concentration of the organic carbide needs to be reduced from hundreds ppm to dozens of ppm or even a few ppm on the basis of removing various metal impurities and non-metal impurities.

At present, various purification methods are used for industrial grade hydrogen peroxide, such as a rectification method, a resin adsorption method, an adsorbent adsorption method, a membrane separation method, an extraction method and the like. In the prior art, in actual operation, a plurality of resin towers are mostly used for purification by using a resin adsorption method and resin ion exchange in a combined manner, and specifically, a TOC resin adsorption tower, a cation exchange resin tower and an anion exchange resin tower which are sequentially connected in a combined manner in a series manner are arranged. Introducing chemical reagent-grade hydrogen peroxide into a TOC resin adsorption tower at normal temperature to remove TOC impurities in the TOC resin adsorption tower, then cooling the treated hydrogen peroxide to low temperature (generally about 10 ℃) and sequentially introducing the hydrogen peroxide into a cation exchange resin tower and an anion exchange resin tower to remove cations and anions respectively, wherein the purpose of cooling at this stage is to generate certain bubbles in the process of removing the anions, and if the temperature is too high, the hydrogen peroxide is easy to explode, so that the hydrogen peroxide enters the ion exchange resin tower after being cooled firstly. However, since the TOC content in the industrial-grade hydrogen peroxide is generally high and the amount of ionic impurities is also high, when the resin adsorption and anion-cation exchange method is adopted, the load on the resin tower is high, the energy consumption is high, a plurality of resin towers which are used in combination need to be installed on the equipment for impurity removal and purification, and the resin filler in the resin tower needs to be replaced or regenerated frequently, so that the purification cost is also high.

Disclosure of Invention

In order to solve the technical problems, the invention provides a purification method for removing TOC in hydrogen peroxide at low temperature, which directly carries out low-temperature cooling and then filtering on industrial-grade hydrogen peroxide to be treated, can remove TOC in the industrial-grade hydrogen peroxide at low temperature without resin adsorption, and then carries out removal of cations and removal of anions, thereby reducing the load of an anion-cation resin tower.

The technical scheme of the invention is as follows:

a purification method for removing TOC in hydrogen peroxide at low temperature mainly comprises a cooling stage and a filtering stage which are sequentially carried out, wherein the cooling stage is to cool industrial-grade hydrogen peroxide to 0-8 ℃, and the filtering stage is to filter the cooled hydrogen peroxide by a membrane filter to remove TOC.

The further technical scheme is as follows:

in the cooling stage, industrial-grade hydrogen peroxide is cooled to 4-8 ℃.

The further technical scheme is as follows:

and in the cooling stage, cooling industrial-grade hydrogen peroxide to 8 ℃.

The further technical scheme is as follows:

the membrane filter adopted in the filtering stage is a membrane filter using a polyethersulfone membrane folding filter element, and the filtering precision of the polyethersulfone membrane folding filter element is 0.05-0.1 mu m.

The further technical scheme is as follows:

the filtering precision of the polyethersulfone membrane folding filter element is 0.1 mu m.

The further technical scheme is as follows:

the filtering precision of the polyethersulfone membrane folding filter element is 0.05 mu m.

The further technical scheme is as follows:

the polyethersulfone membrane folding filter element is rinsed by ultrapure water before use.

The further technical scheme is as follows:

the TOC content of the industrial-grade hydrogen peroxide to be treated is below 2500 ppm.

The beneficial technical effects of the invention are as follows: the invention sequentially cools and filters industrial-grade hydrogen peroxide to be treated, wherein

1. In the cooling stage of the invention, the industrial grade hydrogen peroxide to be treated is directly cooled to a temperature lower than that in the conventional operation, so that TOC impurities in the hydrogen peroxide can be better separated out, and the hydrogen peroxide can be filtered out in the later period;

2. the filtering membrane selected in the filtering stage is washed by ultrapure water before use, so that the dissolved matters of the filter element can be reduced to the maximum extent, and the filtering is more effective;

3. the membrane filter selected in the filtering stage is a filtering membrane with a special membrane material, and insoluble substances precipitated in the previous stage due to cooling can be completely filtered by utilizing the action of the polarity and the surface tension of the filtering membrane made of the material and the selection of the filtering precision of the filtering membrane, so that the TOC content in the treated hydrogen peroxide is lower than 20 ppm;

4. according to the treatment process, the TOC is removed directly through cooling and filtering without an additional resin tower in the TOC removing stage, and then the anion and the cation are removed through the resin towers in sequence, so that the hydrogen peroxide entering the subsequent anion and cation removing resin tower can be ensured to have higher purity on the basis of omitting one resin tower in the whole impurity removing stage, and the service life of the subsequent resin tower can be prolonged.

Detailed Description

In order to clearly understand the technical means of the present invention and to implement the technical means according to the content of the specification, the following embodiments are further described in detail in the following with reference to the specific examples, which are used for illustrating the present invention and are not intended to limit the scope of the present invention.

The purification method for removing TOC in hydrogen peroxide at low temperature mainly comprises a cooling stage and a filtering stage which are sequentially carried out.

The TOC content of the industrial-grade hydrogen peroxide to be treated in the invention is below 2500 ppm.

The cooling stage is to cool the technical grade hydrogen peroxide water to 0-8 ℃, preferably to 4-8 ℃, more preferably to 8 ℃.

And in the filtering stage, the cooled hydrogen peroxide is filtered by a membrane filter to remove TOC. Wherein the adopted membrane filter is a membrane filter using a polyethersulfone membrane folding filter element, and the polyethersulfone membrane folding filter element has the filtration precision of 0.05-0.1 mu m, and preferably has the filtration precision of 0.1 mu m or 0.05 mu m. The polyethersulfone membrane folding filter element is rinsed by using ultrapure water before use, and more preferably, the rinsing time by using ultrapure water is not less than 3 h.

The model of the polyethersulfone membrane folding filter element selected in the following specific embodiment is SE00120KLS, the filtering precision is 0.1 mu m, the length of the filter element is 20 percent, the lower end of the connector is a 226 connector, the upper end of the connector is a wing plate, and the selected sealing material is silicon rubber. The following comparative example was conducted on the basis of example 3, and the polyethersulfone membrane folded filter element selected was identical to the filter element selected in example 3.

Table 1 hydrogen peroxide solution treatment process and treatment results in specific examples and comparative examples

Compared with the specific example 3, the comparative example 1, the comparative example 2 and the comparative example 3 respectively have the same other treatment processes, and the cooling temperature of the industrial-grade hydrogen peroxide to be treated is different only in the cooling stage. It can be seen from the results that when the cooling temperature is 8 ℃, the TOC content in the hydrogen peroxide after the subsequent filtration stage is the lowest; it can also be seen that the lower the cooling temperature, the lower the TOC content of the hydrogen peroxide after the subsequent filtration stage (see comparative example 1, comparative example 2 and comparative example 3).

Comparative example 4, comparative example 5 and comparative example 6 each compare with the specific example 3, the other treatments are identical, and the time for flushing the filter element before filtration is different. The results show that when the filter element is not flushed, the TOC content of the filtered hydrogen peroxide is still higher although the TOC content of the filtered hydrogen peroxide is reduced, and the filter element still has certain advantages compared with the prior art; when the rinsing time is less than 3 hours (e.g., 1 hour and 2 hours), the TOC content is still high although it is reduced. Therefore, the flushing time can effectively ensure that the TOC content in the filtered hydrogen peroxide is the lowest by adopting the method.

Comparative example 7 compared with the specific example 3, the treatment process was the same, only the filter element selected was different, and the filter membrane in the filter element selected in comparative example 6 was a DU PONT permasep RTMB-10 polyamine membrane. The results show that when a membrane filter which is commonly used for filtering hydrogen peroxide on the market is selected, the polarity of the membrane filter is different due to different membrane materials, the filtering effect is obviously different, and the purifying effect is better when the membrane filter is selected.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, it should be noted that, for those skilled in the art, many modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.