KR20210052674A - Method for preparing ion exchange resin with reduced metal impurity content - Google Patents

Abstract

The present invention relates to a method for preparing an ion exchange resin with a reduced metal impurity content, and more particularly, to a method for preparing an ion exchange resin of which the content of metal ions is extremely low and total organic carbon (TOC) elution is low, and has excellent resistivity to be used in the manufacture of ultrapure water for semiconductors. The method comprises the following steps of: (1) making an ion exchange resin contact with a mineral acid solution at 30°C or higher; and (2) washing the ion exchange resin obtained in the step (1) with ultrapure water.

Description

Manufacturing method of ion exchange resin with reduced metal impurity content{METHOD FOR PREPARING ION EXCHANGE RESIN WITH REDUCED METAL IMPURITY CONTENT}

The present invention relates to a method of manufacturing an ion exchange resin having a reduced content of metal impurities, and more specifically, an extremely low content of metal ions, a low total organic carbon (TOC) elution, and an excellent resistivity value, resulting in ultrapure water for semiconductors. It relates to a method for producing an ion exchange resin used in the manufacture of.

In recent years, in the field of semiconductor manufacturing, high purity has been required for cleaning and chemicals along with production machines or gases applied in the semiconductor manufacturing process, along with high integration of semiconductor devices. ), etc. Also, interest in very high purity water is increasing.

Electricity generated when washing water such as ultrapure water or various liquid agents represented by resist solutions contain large amounts of various metal ions such as sodium ions, calcium ions, magnesium ions, iron ions, copper ions, and zinc ions, which are ionic impurities. · It can cause a great adverse effect on the quality of electronic products. For this reason, liquid agents used in the manufacture of electric and electronic products are required to have high purity that hardly contain impurities and metal ions.

Liquid agents having a small content of such metal ions are manufactured by being purified by ion exchange resin. However, when a large amount of metal impurities are included in the ion exchange resin, metal ions are eluted into the liquid agent, making it difficult to obtain a high-purity liquid agent.

In order to solve the problem caused by the metal contained in the ion exchange resin, Japanese Patent Laid-Open Publication No. 2007-117781 discloses a high-purity mine in which the amount of metal impurities is 1 mg/L (ppm) or less in the ion exchange resin containing metal ions. Disclosed is a method of reducing the amount of impurities of metal ions in an ion exchange resin by passing an aqueous solution in a downward flow. However, since a mineral acid solution with a low content of impurities metal ions (high purity mines with an impurity amount of 1 mg/L or less) is manufactured through an additional purification process, it is very expensive, and the photo acid solution comes into contact in the purification operation of the ion exchange resin. Because the pumps and pipes that are used must also contain a coating made of a special material that is not contaminated by metal ions, high cost is incurred for the establishment of ion exchange resin purification equipment, and there is difficulty in maintaining and managing these equipment so that they are not contaminated . In addition, in the process of passing through a large amount of high-purity mineral acid aqueous solution, the amount of treatment liquid is increased, and a cost loss for neutralization treatment/disposal treatment of the generated treatment liquid may occur.

For this reason, there is a need for a method capable of reducing the metal ion content in the ion exchange resin used in the production of ultrapure water for semiconductors through a more economical treatment method at low cost.

The present invention is to solve the problems of the prior art as described above, the content of metal ions is extremely low, total organic carbon (TOC) elution is low, and the specific resistance value is excellent, so that the ion exchange resin used in the manufacture of ultrapure water for semiconductors. The method of manufacturing is made into a technical problem.

In order to solve the above technical problem, the present invention includes the steps of: (1) contacting an ion exchange resin with a photo acid solution of 30° C. or higher; And (2) washing the ion exchange resin obtained from the step (1) with ultrapure water, wherein the total content of metal impurities in the washed ion exchange resin is 5 mg/LR or less. Provides a method of manufacturing a resin.

According to another aspect of the present invention, an ion exchange resin prepared by the above method is provided.

The ion exchange resin (preferably a cation exchange resin, more preferably a strongly acidic cation exchange resin) prepared according to the method of the present invention has a very low content of metal impurities in the ion exchange resin itself, so that there are few eluted metal impurities, and total organic carbon. (TOC) The elution is low and the specific resistance value is excellent, so it can be suitably used for manufacturing ultrapure water for semiconductors.

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

The present invention comprises the steps of (1) contacting an ion exchange resin with a photo acid solution of 30° C. or higher; And (2) washing the ion exchange resin obtained from the step (1) with ultrapure water, wherein the total content of metal impurities in the washed ion exchange resin is 5 mg/LR or less. It relates to a method of manufacturing a resin.

The ion exchange resin (preferably a cation exchange resin, more preferably a strongly acidic cation exchange resin) obtained by the production method of the present invention has a total organic carbon (TOC) elution amount of 5 ppb or less (preferably 4.5 ppb or less, more Preferably it is 4.3 ppb or less, even more preferably 4.2 ppb or less), has a specific resistance of 16 ㏁·cm or more, and metal impurities (sodium ions, calcium ions, magnesium ions, iron ions, copper ions) present in the ion exchange resin And zinc ions, etc.) having a total content of 5 mg/LR (amount of metal mg per 1 L unit volume of the ion exchange resin in water swelling state) or less (preferably 4 mg/LR or less, more preferably 3 mg/LR). Or less).

The manufacturing method of the present invention includes the step of (1) contacting an ion exchange resin with a photoacid solution of 30°C or higher.

As the photoacid solution used in step (1), an aqueous solution is preferable, and as a specific example, an aqueous hydrochloric acid solution, an aqueous sulfuric acid solution, an aqueous nitric acid solution, an aqueous phosphoric acid solution, or a mixed solution thereof may be used, and an aqueous hydrochloric acid solution that is easy to handle at low cost is used. It may be desirable to use.

In step (1), the "contact" between the ion exchange resin and the photoacid solution includes not only passing the photoacid solution through the ion exchange resin, but also immersing the ion exchange resin in the photoacid solution. In the above step (1), it is preferable to contact the ion exchange resin with the photoacid solution using a batch method in which the ion exchange resin is heated by contacting the photoacid solution.

The ion exchange resin used in the manufacturing method of the present invention may be, for example, a strong acid cation exchange resin, a weak acid cation exchange resin, a strong basic anion exchange resin or a weak basic anion exchange resin, but preferably a strong acid cation exchange resin. have. In addition, the ion exchange resin may be an ion exchange resin having an ion exchange group of Na type, H type or NH type, and preferably H type ion exchange resin may be used.

The total content of metal impurities in the mineral acid solution used in step (1) may be 0.01 mg/L to 3 mg/L, and when the total content of metal impurities in the photo acid solution is 10 mg/L or more, the ion exchange resin Metal impurities in the inside cannot be reduced, and on the contrary, metal impurities may be adsorbed to the ion exchange resin.

The temperature of the photoacid solution used in step (1) may be 30°C or higher, for example, 35°C or higher, 40°C or higher, or 45°C or higher. When the temperature of the photoacid solution is less than 30° C., the ion exchange resin does not expand properly, and metal impurities present in the cross-linking cannot be effectively removed. However, when the temperature of the mineral acid solution exceeds 50° C., chemical bonds constituting the ion exchange resin may be broken, resulting in an increase in the amount of total organic carbon emitted, and cost increase due to temperature increase may occur.

When passing the photoacid solution through the ion exchange resin, the photoacid solution is heated to 30℃ or higher, and then the photoacid solution is passed through the ion exchange resin to make them contact. When the ion exchange resin is immersed in the photoacid solution, immersion After raising the temperature to 30° C. or higher, or after raising the temperature of the photoacid solution to 30° C. or higher, the ion exchange resin may be immersed in the elevated photo acid solution.

The concentration of the photoacid solution used in step (1) may be 1 to 10% by weight, for example, 1% by weight or more, 2% by weight or more, 3% by weight or more, or 4% by weight or more, and 10% by weight % Or less, 8% by weight or less, 7% by weight or less, or 6% by weight or less. If the concentration of the mineral acid solution is too high, the device used for the treatment of the ion exchange resin may be corroded by acid or decomposition of the chemical bonds constituting the ion exchange resin, and if the concentration of the mineral solution is too low , The effect of removing metal impurities may be insignificant.

The manufacturing method of the present invention includes the step of (2) washing the ion exchange resin obtained from step (1) with ultrapure water.

In the step (2), the ion exchange resin obtained from the step (1) is 1 ppb or less of total organic carbon (TOC) and ultrapure water having a specific resistance of 18.2 ㏁·cm or more is used, and SV = 20 hr ^-1 to 30 hr ^{By passing the liquid in a downward flow for 15 to 20 hours at a flow rate of -1} , it is possible to prevent re-contamination of metal impurities while removing the mineral acid solution and organic matter.

According to the method of the present invention, metal impurities in the ion exchange resin are removed by a simple operation of contacting the ion exchange resin with a photoacid solution heated to 30° C. or higher in a reactor, which can be eluted when the ion exchange resin is used. Metal impurities can be reduced, total organic carbon (TOC) elution is low, and a high-quality ion exchange resin can be prepared.

The present invention also relates to an ion exchange resin produced by the production method of the present invention.

The ion exchange resin prepared according to the production method of the present invention has a total organic carbon (TOC) elution of 5 ppb or less (preferably 4.5 ppb or less, more preferably 4.3 ppb or less, even more preferably 4.2 ppb or less). , The specific resistance may be 16 ㏁·cm or more, and the total content of metal impurities may be 5 mg/LR or less (preferably 4 mg/LR or less, more preferably 3 mg/LR or less).

Hereinafter, the present invention will be described in more detail through Examples and Comparative Examples. However, the scope of the present invention is not limited to these.

[ Example ]

Example One

(1) Step: Ion exchange resin and Warmed Contacting the mineral solution

Into a 1 L reactor made of Teflon, 200 ml of H-type cation exchange resin (TRILITE MC-08HUP, Samyang Corporation (manufactured by Samyang Corporation)) was added, and an aqueous hydrochloric acid solution (3% by weight) of 2.5 times the volume of the cation exchange resin was added. Next, after raising the temperature in the reactor to 35° C., the mixture was stirred while maintaining the elevated temperature for 3 hours. Thereafter, the hydrochloric acid aqueous solution was drained, and in order to adjust the pH of the cation exchange resin, 2.5 times the volume of ultrapure water was added to the reactor, stirred for 30 minutes, and then the ultrapure water was drained. The process of (Drain) was repeated 3 times.

(2) Step: Washing the ion exchange resin using ultrapure water

After filling 100 ml of the cation exchange resin obtained in step (1) into a column (L 500mm XD 20mm), SV = 20 hr ^-1 using ultrapure water (the volume ratio of the fluid passing through the ion exchange resin volume per unit time) The cation exchange resin was washed by passing water for 20 hours at a downward flow rate of ). At this time, the total organic carbon (TOC) of the ultrapure water was 1 ppb or less, and the specific resistance was 18.2 ㏁·cm or more.

The specific resistance, total organic carbon (TOC), and metal impurity content of the obtained cation exchange resin were measured, and the results are shown in Table 1 below.

Example 2

A cation exchange resin was obtained by performing the same method as in Steps (1) and (2) of Example 1, except that the temperature-raising temperature in Step (1) of Example 1 was changed from 35°C to 30°C. I did. The specific resistance, total organic carbon (TOC), and metal impurity content of the obtained cation exchange resin were measured, and the results are shown in Table 1 below.

Example 3

A cation exchange resin was obtained by performing the same method as in Steps (1) and (2) of Example 1, except that the temperature rising temperature in Step (1) of Example 1 was changed from 35°C to 40°C. I did. The specific resistance, total organic carbon (TOC), and metal impurity content of the obtained cation exchange resin were measured, and the results are shown in Table 1 below.

Comparative example One

The specific resistance, total organic carbon (TOC), and metal impurity content of the H-type cation exchange resin (TRILITE MC-08HUP, Samyang Corporation (manufactured by Samyang Corporation)) of Example 1 in which steps (1) and (2) were not performed were measured. , The results are shown in Table 1 below.

Comparative example 2

A cation exchange resin was obtained in the same manner as in Example 1, except that step (1) of Example 1 was not performed. The specific resistance, total organic carbon (TOC), and metal impurity content of the obtained cation exchange resin were measured, and the results are shown in Table 1 below.

Comparative example 3

A cation exchange resin was obtained in the same manner as in Steps (1) and (2) of Example 1, except that the temperature rising temperature in Step (1) of Example 1 was changed from 35°C to 28°C. I did. The specific resistance, total organic carbon (TOC), and metal impurity content of the obtained cation exchange resin were measured, and the results are shown in Table 1 below.

Comparative example 4

Except that the temperature in the reactor of step (1) of Example 1 was not raised and maintained at room temperature (25±2°C), it was carried out in the same manner as steps (1) and (2) of Example 1 Thus, a cation exchange resin was obtained. The specific resistance, total organic carbon (TOC) and metal impurity content of the obtained cation exchange resin were measured, and the results are shown in Table 1 below.

<Method of measuring physical properties>

Resistivity and total Organic carbon ( TOC ) How to measure

The cation exchange resins obtained in Examples 1 to 3 and Comparative Examples 1 to 4 were filled in a column (L 500 mm XD 20 mm), and ultrapure water having a total organic carbon (TOC) of 0.5 to 1 μg/L (ppb) was lowered. The flow was passed through SV=30 hr ^-1 for 3 hours, and the specific resistance (㏁·cm) and total organic carbon (TOC) (ppb) of the ultrapure water discharged from the column were measured.

Cation ion exchange How to measure the content of metal impurities in the resin

Cations using high purity analytical hydrochloric acid (metal impurity content of 1 mg/L or less) from the cation exchange resins obtained in Examples 1 to 3 and Comparative Examples 1 to 4 using a non-contaminated Teflon glassware Metal impurities inside the exchange resin were eluted, and the eluent was analyzed using ICP-MS. The metal ion content per unit resin amount was calculated from the analysis result value.

[Table 1]

As shown in Table 1, in the case of Examples 1 to 3 according to the present invention, the inside of the ion exchange resin expands as the temperature is raised to 30° C. or higher, so that even metal impurities present in the cross-linking can be effectively removed. It can be seen that the total content of impurities was very low, and accordingly, the specific resistance value was 16.3 ㏁·cm or more, and the total organic carbon outflow (ΔTOC) was very low as 4.2 ppb or less.

However, in the case of a commercially available ion exchange resin (Comparative Example 1), the total content of metal impurities was very high, so the specific resistance value was low, the total organic carbon outflow (△TOC) was also very high, and only ultrapure water washing treatment was performed on the commercially available ion exchange resin. In the case of (Comparative Example 2), the total content of metal impurities was very high, so the specific resistance value was lowered, and the total organic carbon outflow (△TOC) was relatively high, and a photo-acid solution at 28°C was used (Comparative Example 3). When and room temperature photoacid solution was used (Comparative Example 4), the total content of metal impurities was relatively high, so it was not suitable for use in manufacturing ultrapure water for semiconductors, the specific resistance value was low, and the total organic carbon outflow (△TOC) was also It can be seen that it was relatively high.

Claims (7)

(1) contacting an ion exchange resin with a photo acid solution of 30° C. or higher; And
(2) washing the ion exchange resin obtained from step (1) with ultrapure water; including,
The total content of metal impurities in the washed ion exchange resin is 5 mg/LR or less,
A method of manufacturing an ion exchange resin with reduced metal impurities The method of claim 1,
The mineral acid solution is selected from the group consisting of an aqueous hydrochloric acid solution, an aqueous sulfuric acid solution, an aqueous nitric acid solution, an aqueous phosphoric acid solution, or a combination thereof. The method of claim 1,
A method for producing an ion exchange resin having a reduced content of metal impurities, wherein the concentration of the mineral acid solution is 1 to 10% by weight. The method of claim 1,
(2) A method for producing an ion exchange resin having a reduced content of metal impurities, having a total organic carbon (TOC) of 1 ppb or less and a resistivity of 18.2 MΩ·cm or more. The method of claim 1,
A method for producing an ion exchange resin having a reduced content of metal impurities, wherein the ion exchange resin is a cation exchange resin. The ion exchange resin prepared by the method of any one of claims 1 to 5. The ion exchange resin according to claim 6, wherein the total organic carbon (TOC) elution amount is 5 ppb or less, the specific resistance is 16 MΩ·cm or more, and the total content of metal impurities is 5 mg/L-R or less.