JP5053587B2 - High-purity production method of alkali metal hydroxide - Google Patents

High-purity production method of alkali metal hydroxide Download PDF

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JP5053587B2
JP5053587B2 JP2006207287A JP2006207287A JP5053587B2 JP 5053587 B2 JP5053587 B2 JP 5053587B2 JP 2006207287 A JP2006207287 A JP 2006207287A JP 2006207287 A JP2006207287 A JP 2006207287A JP 5053587 B2 JP5053587 B2 JP 5053587B2
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alkali metal
metal hydroxide
chelate resin
aqueous solution
alkaline earth
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JP2008031004A (en
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次功 刑部
郁雄 石田
麻矢 税田
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東亞合成株式会社
鶴見曹達株式会社
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Description

  The present invention relates to a method for producing a high-purity alkali metal hydroxide capable of effectively removing an alkaline earth metal in a crude alkali metal hydroxide.

  For example, in the manufacture of electronic components such as semiconductor wafers and color filters, an alkali metal hydroxide is used to planarize the wafer surface by etching, remove the resist material, or clean the surface. Alkali metal hydroxide used in the manufacture of these electronic components does not contain metal impurities such as calcium, magnesium, nickel, chromium, iron, and copper to prevent deterioration of semiconductor wafers and semiconductor device characteristics. It is required to use a high purity alkali metal hydroxide. In addition, there is an increasing demand for drugs that do not contain such impurities in medical use and cosmetics.

  As a method for producing high-purity alkali metal hydroxide, a production method for purifying alkali hydroxide with an ion exchange membrane can be mentioned (for example, see Patent Document 1). Although this method has a sufficiently high refining accuracy, it takes a relatively long time to install equipment, and it is difficult to obtain highly purified alkali hydroxide anywhere. Also disclosed are a method for removing nickel in potassium hydroxide with activated carbon (for example, see Patent Document 2) and a method for removing iron and nickel in sodium hydroxide with activated carbon (for example, see Patent Document 3). Yes. These can be handled with relatively simple equipment and can be highly purified, but there are few metal species that can be purified. In addition, some alkaline earth metals and metal species elute from here, and this pretreatment may take effort.

  On the other hand, it is known to supplement a metal with a chelate resin or an ion exchange resin to purify a solution to be contacted or recover a metal. As examples of the purification of alkali hydroxide by these resins, purification by a chelate resin having a specific structure is disclosed (for example, see Patent Document 4). These are disclosed that they can be purified by removing heavy metals such as iron and that heavy metals are removed using magnesium hydroxide, but they do not remove alkaline earth metal compounds.

Aminophosphate-type chelate resins have been reported as those capable of removing calcium, strontium, and the like in salt water (see, for example, Patent Document 5). And it describes that it has selectivity with respect to bivalent metal ions, such as calcium, magnesium, strontium, in high concentration salt solution.
An iminodiacetic acid type or aminophosphate type chelate resin has been reported as a resin having the ability to selectively adsorb alkaline earth metals even in a sample containing a large amount of inorganic salt (see, for example, Patent Document 6). .

  Alkaline hydroxides in the market account for 48% of both typical sodium hydroxide and potassium hydroxide, and they vary in use, but in the range of 20-60%, including temporary storage. Although it is often stored and used, it has become a method that can be easily purified in these concentration ranges.

Japanese Patent Application Laid-Open No. 09-078276 JP 2000-203828 A JP-A-2005-001955 JP-A-01-027648 JP 05-032714 A JP-A-01-292249

  The present invention provides a method for producing a high-purity alkali metal hydroxide aqueous solution capable of removing an alkaline earth metal contained in a crude alkali metal hydroxide aqueous solution in a high concentration state. .

As a result of intensive investigations on the removal of alkaline earth metal in the aqueous solution of crude alkali metal hydroxide at a concentration that is distributed in the market, it was found that the alkaline earth in the crude alkali metal hydroxide by the chelate resin having an N-methylglucamine group. The present inventors have found that similar metals can be removed and have completed the present invention. That is, the present invention specifically includes
(1) Ri manufacturing method der high purity alkali metal hydroxide aqueous solution, and removing the alkaline earth metal in the crude alkali metal hydroxide aqueous solution using a chelating resin having an N- methylglucamine group,
( 2 ) Alkaline earth in a crude alkali metal hydroxide aqueous solution using the chelate resin having an N-methylglucamine group as described in 1 above and a chelate resin having an aminophosphate group and / or a chelate resin having an iminodiacetic acid group The method for producing a high-purity alkali metal hydroxide aqueous solution according to the above 1, which removes a metal species,
( 3 ) It is a manufacturing method of the high purity alkali metal hydroxide aqueous solution in any one of said 1-2 whose density | concentration of the said crude alkali metal hydroxide aqueous solution is 20 to 60 weight%.

  According to the production method of the present invention, alkaline earth metal can be removed even from a high-concentration crude aqueous alkali metal hydroxide solution. Can be provided.

Examples of the crude alkali metal hydroxide handled in the present invention include sodium hydroxide and potassium hydroxide, and potassium hydroxide is more preferable.
In the present invention, the concentration of the crude alkali metal hydroxide aqueous solution can be expected to reduce alkaline earth metal at any concentration, but it is necessary to carry out unnecessary operations such as transportation efficiency, storage efficiency, and subsequent simmering to a high concentration by handling. 20% or more is preferable, and 60% or less is preferable as a range not to be solidified, more preferably 35% or more and 55% or less, and particularly preferably 40% or more and 53% or less.

  The crude alkali metal hydroxide used is exclusively produced by the ion exchange membrane method, but as alkaline earth metals and metals as impurities contained therein, calcium, magnesium, strontium, Barium, iron, nickel, copper, zinc, lead, cadmium, manganese, cobalt, vanadium, molybdenum, chromium, zirconium, silver, tin, aluminum, mercury, antimony, titanium, bismuth, gallium, thallium, etc. It is desirable to reduce as much as possible. Furthermore, even if a specific metal is contained in a small amount, the quality of the product is greatly affected, and it is preferable that calcium and magnesium can be reduced to a lower level.

  In the present invention, impurities of alkaline earth metal such as calcium or magnesium in the high-purity alkali metal hydroxide are 1000 ppb or less, preferably 100 ppb or less, and 1 ppb or more.

  The crude alkali metal hydroxide aqueous solution suitable for this method varies depending on the alkaline earth metal contained, but the concentration that can be mixed before removal is 10 ppm by weight or less (hereinafter ppm). Preferably, it is 3 ppm or less. In addition, the minimum amount of alkaline earth metal contained in the crude alkali metal hydroxide aqueous solution is larger than the content of each alkaline earth metal in the high-purity alkali metal hydroxide.

In the present invention, N- methylglucamine be based as it any way if Re Ah with a chelating resin having a can be used, and it has a basicity as the chelate resin. As the chelate resin, polystyrene, polystyrene - -CH 2 -N (CH 3) divinylbenzene copolymer or a phenol resin CH 2 - (CHOH) n -CH 2 OH groups (n is about 3 to 5 integer Are more preferable. Specifically, there is one in which an N-methylglucamine group is bonded to a polystyrene-divinylbenzene copolymer. Examples of commercially available products include Diaion CRB02 (trade name, manufactured by Mitsubishi Chemical Corporation), Amberlite IRA743 (trade name, manufactured by Rohm & Haas) and Uniselec UR-3500S (trade name, manufactured by Unitika Ltd.). .

  Examples of aminophosphate-type chelate resins used in the present invention include those obtained by phosphorylating amino groups based on styrene derivatives. Specifically, there are UR-3300S (trade name, manufactured by Unitika Ltd.), Levacit Monoplus TP-260 (trade name, manufactured by LANXESS), Duolite C467 (trade name, manufactured by Sumika Chemtex Co., Ltd.), and the like.

  Examples of the iminodiacetic acid type chelating resin used in the present invention include those having an iminodiacetic acid group based on, for example, a styrene derivative. Specifically, Diaion CR11 (trade name, manufactured by Mitsubishi Chemical Co., Ltd.), Lebatit Monoplus TP-208 (trade name, manufactured by LANXESS), Sumichel MC-700 (trade name, manufactured by Sumika Chemtex Co., Ltd.), Amber Light IRC748 (trade name, manufactured by Rohm & Haas).

  In this invention, what is necessary is just to determine the usage-amount of this chelate resin by content of the alkaline-earth metal in crude alkali hydroxide. For example, when adsorbing in a packed tower, the superficial velocity (hereinafter referred to as SV) is SV = 0.1-20 [1 / h], more preferably SV = 0.2-10 [1 / h], particularly preferably. Can adsorb alkaline earth metals efficiently by contact at SV = 0.3-5 [1 / h]. This range is preferable because the alkaline earth metal can be efficiently removed.

  In the production method of the present invention, the operating temperature is about 0 ° C to 60 ° C, preferably 5 ° C to 50 ° C, more preferably 10 ° C to 45 ° C. It is preferable that the contact temperature with the chelate resin is within this range because the alkaline earth metal in the crude alkali metal hydroxide can be efficiently removed.

The production method of the present invention uses a chelate resin having an N-methylglucamine group (referred to as a chelate resin for boron), and a chelate resin having an aminophosphate group or a chelate resin having an iminodiacetic acid group is used together. It is preferable to use a chelate resin having an aminophosphate group, more preferably, a chelate resin having an aminophosphate group and a chelate resin having an iminodiacetic acid group are more preferably used together, and alkaline earth Similar metals can be removed.

Although the alkaline earth metal in the crude alkali metal hydroxide aqueous solution can be removed by the chelating resin for boron, calcium, magnesium, strontium and barium can be preferably removed, magnesium, strontium and barium can be more preferably removed, and magnesium can be removed. Further preferably, it can be removed.
Alkaline earth metal in the crude alkali metal hydroxide aqueous solution can be removed by using a chelate resin for boron, a chelate resin having an aminophosphate group and / or a chelate resin having an iminodiacetic acid group, but calcium, magnesium, Strontium and barium can be removed preferably, and magnesium, strontium and barium can be removed more preferably.

In the production method of the present invention, the alkaline earth metal in the solution can be easily removed by, for example, filling the chelate resin in a packed tower and passing a crude alkali metal hydroxide aqueous solution therethrough. It is also possible to reduce alkaline earth metal by batch operation such as storing a crude alkali metal hydroxide solution in a tank or the like, adding a resin and stirring.
In the present invention, the chelate resin to which the alkaline earth metal is adsorbed is a known dealkalized earth such as washing with ultrapure water or the like, back washing operation, further treatment with acid such as hydrochloric acid or nitric acid, and washing with water. Regeneration methods using metal-like operations can be used. And the chelate resin reproduced | regenerated in this way can be used for the manufacturing method of this invention.

  When multiple types of chelate resins are used in the production method of the present invention, other types of chelate resins can be used before or after the chelate resin for boron, and these chelate resins can be mixed and used, preferably individually. More preferably, a chelating resin for boron is used in the former stage, and a chelating resin having an aminyl phosphate group and / or an iminodiacetic acid group is used in the latter stage.

  The high-purity alkali metal hydroxide aqueous solution produced using the production method of the present invention can be used after adjusting the concentration depending on the application.

High-purity alkali metal hydroxide manufactured using the manufacturing method of the present invention is used for manufacturing electronic parts such as semiconductor wafers and color filters, planarizing by wafer surface etching, removing resist material, or cleaning the surface. Can be used.
By using the purification method of the present invention, high-purity alkali metal hydroxide used for manufacturing electronic components such as semiconductor wafers and color filters, planarizing by wafer surface etching, removing resist material, or cleaning the surface, etc. Can be provided.

○ Implementation
High-purity alkali hydroxide that removes alkaline earth metal in a crude alkali metal hydroxide aqueous solution using a chelate resin having an N-methylglucamine group, a chelate resin having an aminophosphate group, and a chelate resin having an iminodiacetic acid group A method for producing a metal aqueous solution.
A method for producing a high-purity alkali metal hydroxide aqueous solution, wherein alkaline earth metal in a crude alkali metal hydroxide aqueous solution is removed using a chelate resin having an N-methylglucamine group and a chelate resin having an aminophosphate group.
A method for producing a high-purity alkali metal hydroxide aqueous solution, wherein alkaline earth metal in a crude alkali metal hydroxide aqueous solution is removed using a chelate resin having an N-methylglucamine group and a chelate resin having an iminodiacetic acid group.
How to remove the alkaline earth metal of the crude alkali metal hydroxide in an aqueous solution with a chelating resin having an N- methylglucamine group.
A method for removing an alkaline earth metal in a crude aqueous alkali metal hydroxide solution by using a chelate resin having an N-methylglucamine group, a chelate resin having an aminophosphate group and / or a chelate resin having an iminodiacetic acid group.
A method of removing an alkaline earth metal in a crude alkali metal hydroxide aqueous solution having a concentration of 20 to 60% by weight using a chelate resin having an N-methylglucamine group .
Alkali in a crude alkali metal hydroxide aqueous solution having a concentration of 20 to 60% by weight using a chelate resin having an N-methylglucamine group, a chelate resin having an aminophosphate group and / or a chelate resin having an iminodiacetic acid group A method of removing earth metals.

Examples Hereinafter, the present invention will be described using examples, but the present invention is not limited thereto. In addition,% represents weight%, ppm represents weight ppm, and ppb represents weight ppb.

48% sodium hydroxide aqueous solution of Preparation 1400g of crude sodium hydroxide aqueous solution taken in a resin container, magnesium hydroxide 25mg, calcium carbonate 30mg, strontium carbonate 20mg, barium carbonate 20mg addition, 1 hour by a magnetic stirrer After stirring, the insoluble matter was separated by filtration with a 5 μm polytetrafluoroethylene polytetrafluoroethylene (PTFE) filter. This crude sodium hydroxide solution contained 0.34 ppm magnesium, 5.30 ppm calcium, 9.75 ppm strontium, and 10.18 ppm barium .

48% crude sodium hydroxide aqueous solution of 100g prepared above is taken up in a PTFE vessel, Diaion CRB-02 as boron Chelating resin (trade name, Mitsubishi Chemical Co., Ltd. / functional group N- methylglucamine) and 10 g was added and stirred at room temperature for 2 hours. Then, collected sodium hydroxide aqueous solution, magnesium, performs calcium, strontium, and barium analysis, from the difference after the resin pre-contact and the resin contact, calculated as magnesium, calcium, strontium, and the removal rate of barium. The results are shown in Table 1.

○ Analytical method of calcium, magnesium, strontium, and barium After adding ultrapure water to the collected sample, it was made up with nitric acid to prepare a test solution. This was measured with an ICP emission analyzer, and the concentration of each metal was determined by a calibration curve method with sample concentration correction .

<Comparative Example 1>
In place of the chelate resin used in Example 1, aminophosphoric acid type chelate resin (trade name Levacit Monoplus TP-260, manufactured by LANXESS) was used in the same manner as in Example 1, and magnesium, calcium, The removal rate of strontium and barium was determined. The results are shown in Table 1.

< Comparative example 2>
Magnesium, calcium, strontium, and barium were operated in the same manner as in Example 1 except that an aminophosphate chelate resin (trade name UR-3300S, manufactured by Unitika Co., Ltd.) was used instead of the chelate resin used in Example 1. The removal rate was determined. The results are shown in Table 1.

< Comparative Example 3>
In the same manner as in Example 1 except that an iminodiacetic acid type chelate resin (trade name Levacit Monoplus TP-208, manufactured by LANXESS) was used instead of the chelate resin used in Example 1, magnesium, calcium, The removal rate of strontium and barium was determined. The results are shown in Table 1.

< Comparative example 4>
Magnesium, calcium and strontium were operated in the same manner as in Example 1 except that iminodiacetic acid type chelating resin (trade name Diaion CR-11, manufactured by Mitsubishi Chemical Corporation) was used instead of the chelating resin used in Example 1. The barium removal rate was determined. The results are shown in Table 1.

  The same operation as in Example 1 was performed except that Diaion CRB-02 (trade name) and Levacit Monoplus TP-260 (trade name) were used. As a result, the removal rate of magnesium, calcium, strontium, and barium was improved more than the removal rate using a chelate resin alone.

  The same operation as in Example 1 was performed except that Diaion CRB-02 (trade name) and Levacit Monoplus TP-208 (trade name) were used. As a result, the removal rate of magnesium, calcium, strontium, and barium was improved more than the removal rate using a chelate resin alone.

<Comparative Examples 5-9 >
The same procedure as in Example 1 was performed except that the chelate resin was changed to the following chelate resin or ion exchange resin, and the results are shown in Table 1.
Comparative Example 5 Diaion PK-216 (functional group -SO 3 Na)
Comparative Example 6 Diaion PK-228 (functional group -SO 3 Na)
Comparative Example 7 Diaion WA-30 (functional group —CH 2 N (CH 3 ) 2 )
Comparative Example 8 Diaion CR-20 (functional group —CH 2 NH (CH 2 CH 2 NH—) n H)
As above, manufactured by Mitsubishi Chemical Corporation.
Comparative Example 9 Amberlite IRA410JCL (functional group dimethylethanolamine chloride, manufactured by Rohm & Haas Co.).

As a result of treating with Diaion CRB-02 (trade name) and measuring the calcium concentration (ppb) in the same manner as in Example 1 except that a 48% sodium hydroxide aqueous solution containing 20 ppb of calcium was used, the result was less than 20 ppb . .
The lower limit of detection of calcium was 20 ppb.

Since the present invention can remove and purify alkaline earth metals in alkali metal hydroxides, it can be applied to various fields such as semiconductor wafer polishing and other electronic materials, pharmaceuticals, cosmetics, etc. It can be easily applied at any time of acceptance or use.

Claims (3)

  1. A method for producing a high-purity alkali metal hydroxide aqueous solution, wherein an alkaline earth metal in a crude alkali metal hydroxide aqueous solution is removed using a chelate resin having an N-methylglucamine group .
  2. An alkaline earth metal in a crude aqueous alkali metal hydroxide solution is removed using a chelate resin having an N-methylglucamine group, a chelate resin having an aminophosphate group and / or a chelate resin having an iminodiacetic acid group. A method for producing a high-purity alkali metal hydroxide aqueous solution according to 1.
  3. The manufacturing method of the high purity alkali metal hydroxide aqueous solution of Claim 1 or Claim 2 whose density | concentration of the said crude alkali metal hydroxide aqueous solution is 20 to 60 weight%.
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JP5564817B2 (en) * 2009-03-31 2014-08-06 栗田工業株式会社 Ion exchange resin regeneration method and ultrapure water production apparatus
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