JP2008127231A - Method and apparatus for purifying hydrogen peroxide solution - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a high purity hydrogen peroxide solution, by which colloidal metal compound particles (colloid impurities) contained as impurities in a hydrogen peroxide solution can be efficiently removed. <P>SOLUTION: In a method for purifying a raw hydrogen peroxide solution containing impurities by using a purification column filled with an ion exchange resin, a chelate resin or an adsorbing resin or using a RO membrane, the method for purifying the raw hydrogen peroxide solution is characterized by removing colloidal impurities contained in the raw hydrogen peroxide solution as a pretreatment of a purification treatment by adding a chelating agent to the raw hydrogen peroxide solution and then filtering the resulting raw hydrogen peroxide solution with a ceramic filter or by using a cation exchange resin or an anion exchange resin or by (i) adding a chelating agent to the raw hydrogen peroxide solution and then filtering the colloidal impurities contained in the hydrogen peroxide solution with a ceramic filter and (ii) using a cation exchange resin or an anion exchange resin. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for producing purified hydrogen peroxide solution, particularly a method for producing high-purity hydrogen peroxide solution capable of efficiently removing colloidal metal compound particles (colloid impurities) contained as impurities in hydrogen peroxide solution, and The present invention relates to a purification apparatus used in a production method.

  Hydrogen peroxide solution is widely used in many fields such as paper, pulp bleaching, chemical polishing liquid, etc., but in recent years, its use in the electronics industry such as silicon wafer cleaning agents and semiconductor process cleaning agents has increased. In connection with this, high-purity quality in which various impurities in hydrogen peroxide water are reduced as much as possible is required.

  In general, hydrogen peroxide is currently produced mainly by the anthraquinone method. The production method is as follows. First, an anthraquinone derivative such as 2-alkylanthraquinone is hydrogenated in the presence of a hydrogenation catalyst in a water-insoluble solvent to form anthrahydroquinone, and after removing the catalyst, it is oxidized by air. -This is a method for regenerating alkyl anthraquinone and extracting the hydrogen peroxide produced at this time with water to obtain a hydrogen peroxide-containing aqueous solution. This method is called anthraquinone auto-oxidation method (AO method).

  The hydrogen peroxide solution produced by this method contains inorganic ions and compound impurities such as Al, Fe, and Cr due to the material of the apparatus. When hydrogen peroxide containing such metal impurities is used in the semiconductor manufacturing field, the reliability of the obtained semiconductor may be significantly reduced. In particular, in recent years, the requirements for semiconductor reliability have become more sophisticated, so that it is necessary to purify hydrogen peroxide to a lower level of each metal ion component, specifically to the order of ppt or sub-ppt. .

  Conventionally, impurities in hydrogen peroxide water have been removed using ion exchange resins, RO membranes, and the like. However, the amount of impurities of the raw hydrogen peroxide solution produced by the so-called AO method is not constant and varies considerably. Furthermore, the guaranteed items for the raw hydrogen peroxide solution (industrial hydrogen peroxide solution) are low in concentration, evaporation residue, free acid, and stability, and metal impurities important for high-purity purification are not guaranteed. Naturally, the life of the ion exchange resin or RO membrane does not become constant when purified with a refining device composed of ion exchange resin or RO membrane using raw material hydrogen peroxide water with a non-constant amount of impurities. Sometimes it is short. In addition, it often does not reach the level where impurity removal is expected.

  In general, in the purification process of hydrogen peroxide solution, the raw material hydrogen peroxide solution is initially filtered through a MF (microfilter) filter with a pore size of 0.03 to 0.2 μm. The Tyndall phenomenon is observed when a laser beam is applied to hydrogen peroxide that has been concentrated without impurities. Obviously, colloidal impurities are present in the hydrogen peroxide solution. Further, when the clogged filter surface is observed with an SEM (scanning electron microscope), a large amount of spherical foreign matter is captured. When this trapped substance is analyzed with an EPMA electron microanalyzer, an overwhelming amount of Al and other Ca, Fe, etc. are observed.

  We also know from experience that raw material hydrogen peroxide, which uses sodium stannate (colloid) as a stabilizer, can hardly be purified by ion exchange resins. Presumably, sodium stannate (colloid) was adsorbed on the entire surface of the ion exchange resin and inhibited the ion exchange function.

Further, as disclosed in Japanese Patent Application Laid-Open No. 9-2213505 (Patent Document 1), when treated with an ultrafiltration membrane having a pore size of 0.15 μm or less, impurities such as Si, Al, Sn, etc. that are not ionic can be captured. In ultrafiltration, there is no change in the dissolved metal concentration before and after filtration. In addition, when hydrogen peroxide solution is treated with a ceramic filter (ultrafiltration) having a pore diameter of 0.004 to 0.2 μm or less as disclosed in Japanese Patent Application Laid-Open No. 2004-67402 (Patent Document 2), in the example of Reference Document 2, Si 18% , Al72%, Fe50%, organic matter 27.8%, etc. can be removed, but these are temporary traps that leak from the filter over time and become contaminated, which is insufficient for practical use. In these Patent Documents 1 and 2, colloids are not recognized at all as impurities. Furthermore, there has never been a prior art that shows that colloidal impurities exist in hydrogen peroxide water.
Japanese Patent Laid-Open No. 9-2213505 JP 2004-67402 A

  For this reason, the advent of a method capable of efficiently removing colloidal impurities contained in hydrogen peroxide water produced by the AO method has been desired.

  Under such circumstances, the present inventors have intensively studied to solve the above-mentioned problems. As a result, the hydrogen peroxide water purifying apparatus composed of an ion exchange resin, an RO membrane, etc. It has been found that the cause of defects that are short-lived and do not reach the purification standard is the colloidal metal compound particles (colloid impurities) in the raw hydrogen peroxide. In general, colloid means dispersed particles when a substance is dispersed as particles larger than atoms or small molecules. Colloidal particles are approximately in the range of 1-100 nm in diameter.

  A high purity aluminum material is used in the manufacturing process in which the raw hydrogen peroxide solution is manufactured. In general, an aluminum material prevents erosion by an oxide film produced by hydrogen peroxide solution, but there is a literature that partly erodes and forms white precipitate of insoluble aluminum hydroxide. These colloidal impurities are produced in the raw material hydrogen peroxide manufacturing process, but they are very small particles and have a structure of hydroxide or oxide hydrate. It has the property of being easily absorbed. For this reason, the present inventors have found that colloidal impurities are adsorbed on the ion exchange resin or the RO membrane to reduce its purification ability.

  When colloidal impurities are adsorbed on the ion exchange resin, diffusion of ions in the ion exchange resin particles is inhibited, and the ion exchange reaction rate is lowered. Further, the adsorbed colloidal impurities are partly desorbed and cause the treated hydrogen peroxide solution to deteriorate. Adsorption of this colloidal impurity may be partly irreversibly adsorbed, and may not be sufficiently desorbed by normal regeneration, gradually depositing on the ion exchange resin and reducing the life of repeated regeneration, Furthermore, regeneration failure occurs early and must be discarded. When colloidal impurities are adsorbed on the RO membrane, the membrane is closed and the transmittance decreases, making it impossible to process. Since the RO membrane cannot use strong acid or alkali, it is difficult to clean the membrane, and eventually the membrane must be discarded.

In addition, although an attempt was made to filter and capture colloidal impurities with a filter as described above as a pretreatment, most colloidal impurities pass through filtration with a 0.03 μm MF filter. Since the pore diameter of a general organic film such as Teflon (registered trademark) or polyolefin is wide and has a pore diameter more than 10 times the nominal diameter, it cannot always be sufficiently captured. Furthermore, the MF filter has a flow path only in one direction to the filtration membrane in the closed space due to the structure (dead end flow), and the trapped substance is pushed into the membrane surface and from the membrane surface into the membrane. The present inventors have found that a large amount of colloid cannot be captured because there is little space in the membrane for holding the trapped material and the membrane is finally removed from the membrane.

  Therefore, as a result of further studies by the present inventors, metal impurities such as Al, Fe, K, Pb, Ca, Zn, Mg, and Cr are found in the hydrogen peroxide water produced by the AO method. We found that metal impurities exist as colloids in the structure of metal hydroxides and oxide hydrates, and that the size is about 1 nm to 100 nm. As a pretreatment in the water purification process, it has been found that if this colloid is captured, the life can be extended without degrading the purification ability of the ion exchange resin for purifying hydrogen peroxide and the RO membrane.

That is, the constituent requirements of the present invention are as follows.
(1) In a method of purifying a raw material hydrogen peroxide solution containing impurities using a purification tower packed with an ion exchange resin, a chelate resin or an adsorption resin, or using a RO membrane,
As a pretreatment for the purification process,
A method for purifying hydrogen peroxide, in which a chelating agent is added to a raw material hydrogen peroxide solution and then filtered through a ceramic filter to remove colloidal impurities contained in the hydrogen peroxide solution.
(2) In a method of purifying a raw material hydrogen peroxide solution containing impurities using a purification tower packed with an ion exchange resin, a chelate resin or an adsorption resin, or using a RO membrane,
As a pretreatment for the purification process,
A method for purifying hydrogen peroxide that removes colloidal impurities contained in hydrogen peroxide water using a cation ion exchange resin or an anion ion exchange resin.
(3) In a method of purifying a raw material hydrogen peroxide solution containing impurities using a purification tower packed with an ion exchange resin, a chelate resin or an adsorption resin, or using a RO membrane,
As a pretreatment for the purification process,
(i) After adding the chelating agent to the raw hydrogen peroxide solution, filtering the colloidal impurities contained in the hydrogen peroxide solution with a ceramic filter; and
(ii) A method for purifying hydrogen peroxide, wherein colloidal impurities contained in the hydrogen peroxide solution are removed by a cation ion exchange resin or an anion ion exchange resin.
(4) Hydrogen peroxide solution containing impurities is contacted with ion exchange resin, chelate resin or adsorption resin using a purification tower packed with ion exchange resin, chelate resin or adsorption resin, and is peroxidized. A purification device for purifying hydrogen water using a purified hydrogen peroxide solution or a RO membrane;
As a pretreatment means to remove colloidal impurities contained in the raw hydrogen peroxide water,
(i) circulation tank, circulation pump and ceramic filter and / or
(ii) A purified hydrogen peroxide water purifier comprising a purification cylinder filled with an ion exchange resin filled with an ion exchange resin made of a cation ion exchange resin or an anion ion exchange resin.

  ADVANTAGE OF THE INVENTION According to this invention, the colloidal impurity which was the cause of reducing the refinement | purification life and refinement | purification ability at the time of refine | purifying hydrogen peroxide can be filtered effectively. For this reason, if the colloid is captured and removed by the method of the present invention, the life can be extended without degrading the purification ability of the ion exchange resin for purifying hydrogen peroxide solution and the RO membrane.

Hydrogen peroxide solution purification process of the present invention is a purification method for capturing and removing the colloid of hydrogen peroxide in water as a pretreatment of hydrogen peroxide water purification device comprising an ion exchange resin or RO membrane.

The method of capturing and removing the colloid employed in the present invention includes (1) ultrafiltration with a ceramic filter, and (2) contact with an ion exchange resin of a cation ion exchange resin or an anion ion exchange resin. .
(1) Ultrafiltration of ceramic filter When ultrafiltration is performed with a ceramic filter, a chelating agent is added in advance to the raw material hydrogen peroxide solution, and ultrafiltration is performed with a ceramic filter having a pore diameter of 20 nm or less.

The hydrogen peroxide concentration in the hydrogen peroxide water used is not particularly limited as long as it is 70% by weight or less. If the concentration is too high, the durability of the filter or device may be reduced.
The chelating agent is added so that the colloid is aggregated and grown and does not pass through the filtration membrane. The chelating agent added to the hydrogen peroxide solution surrounds the colloid, reduces the charge on the surface of the colloid, causes aggregation between the colloids, causes intermolecular crosslinking, and enlarges the colloidal impurities. The polymerized colloidal impurities are condensed and grown to a size of several tens of nm to several hundreds of nm and do not pass through a ceramic filter of 20 nm or less. If a chelating agent is not used, most colloidal impurities pass through the filter over time even when filtering through a ceramic filter of 20 nm or less.

  As the chelating agent, a phosphorus compound is usually used. Examples of phosphorus compounds include aminotri (methylenephosphonic acid) and salts thereof, 1-hydroxyethylidene-1,1-diphosphone and salts thereof, ethylenediaminetetra (methylenephosphonic acid), diethylenetriaminepenta (methylenephosphonic acid) and salts thereof, nitrilomethylene At least one phosphorus selected from the group consisting of phosphonic acid and its salt, 1,2-propylenediaminetetra (methylenephosphonic acid) and its salt, metaphosphoric acid and its salt, polyphosphoric acid and its salt, pyrophosphoric acid and its salt, etc. System compounds are preferably used.

  Such a phosphorus compound is desirably added in an amount of 10 to 100 ppm (as P), preferably 30 to 100 ppm, based on the hydrogen peroxide solution. It is desirable to age at least one day after adding the phosphorus compound. Ripening may be under stirring conditions or non-stirring conditions. Also, the aging temperature is not particularly limited, but may be usually room temperature. This aging causes the colloidal impurities to aggregate and grow to such a size that they cannot pass through the filtration membrane.

  The hydrogen peroxide solution containing the agglomerated and grown colloid is ultrafiltered with a ceramic filter. As the filter, a known porous ceramic filter made of an inorganic material such as alumina, zirconium oxide or titanium oxide can be used. The pore diameter is 20 nm or less, preferably 20 to 4 nm or less. As a filtration method, it is desirable to use a hollow type porous ceramic filter and a cross flow method (flowing liquid parallel to the inner surface of the membrane and filtering by the flowing pressure). When the cross flow is used, since the colloid deposited in the filter shape is filtered while being washed away with the liquid, the permeation filtration flow rate can be maintained for a long time.

The filter filtration pressure ((inlet pressure + outlet pressure) / 2) is 0.2 MPa or less, preferably 0.16 MPa or less. With this filtration pressure, the colloid can be efficiently filtered.
When the hydrogen peroxide solution added with the chelating agent is ultrafiltered with a ceramic filter, 95% or more of colloidal impurities in the hydrogen peroxide solution are removed. The most colloidal impurity is Al colloid, which cannot be removed at all by ordinary MF filter filtration, but 99% can be removed by ultrafiltration of ceramic filters. Since Al can be physically removed, it can be seen that most Al in the hydrogen peroxide solution is not an ion (having a diameter of about several millimeters) but a colloid. The filter is regularly backwashed so that colloidal impurities deposited on the ceramic filter do not clog the filter, or the colloid-rich hydrogen peroxide solution in the concentration tank is periodically removed. This will prolong the life of the ceramic filter.

If the ceramic filter is clogged, the performance can be recovered by washing with an inorganic acid, so it can be used over and over again.
(2) Capture of cation ion exchange resin or anion ion exchange resin with ion exchange resin As another means of capturing and removing colloids, the raw material hydrogen peroxide solution is passed through the ion exchange resin to capture and remove colloidal impurities. It is. Specifically, a cation ion exchange resin, an anion ion exchange resin, a mixed bed of cation ion exchange resin / anion ion exchange resin, or the like is used. The hydrogen peroxide concentration in the hydrogen peroxide water is not particularly limited as long as it is 70% by weight or less as described above.

The cation ion exchange resin is used in H ⁺ type cation ion exchange.
In general, the cation ion exchange resin is preferably a strongly acidic cation ion exchange having a network molecular structure in which a sulfonic acid group is introduced into a styrene-divinylbenzene crosslinked copolymer. Examples thereof include PK216, SK1B, and IR-120B. These resins are generally marketed in Na ion type. These cation ion exchange resins are used after being treated with an inorganic acid such as hydrochloric acid or sulfuric acid.

A commercially available cation ion exchange resin is regenerated with 5% by weight hydrochloric acid or the like. The SV at this time is preferably 20 Hr ⁻¹ or less. Then, it is washed with water until the washing solution becomes neutral.
The anion ion exchange resin is generally a strongly basic resin obtained by chlormethylating a styrene-divinylbenzene cross-linked copolymer, followed by amination with trimethylamine or dimethylethanolamine (the exchange group is quaternary ammonium). Group), a weakly basic resin having a primary or tertiary amine as an exchange group in a styrene-divinylbenzene crosslinked copolymer, a resin having a tertiary amine as an exchange group in an acrylic acid-based crosslinked polymer, a pyridyl group or Examples thereof include a pyridine anion resin made of a polymer having a substituted pyridyl group. Of these, strongly basic anion exchange resins having a quaternary ammonium group are preferred. Many quaternary ammonium group anion exchange resins are commercially available. For example, Diaion PA series (eg PA-316, PA-416), SA series (eg SA-10A, SA-20A) and Amberlite IRA series (eg IRA-400, IRA-410, IRA-900, A typical example is IRA-904). These resins are generally marketed in the chloride ion type. These anion ion exchange resins are used after being treated with a phosphorus compound.

  Examples of phosphorus compounds include aminotri (methylenephosphonic acid), ethylenediaminetetra (methylenephosphonic acid), 1-hydroxyethylidene-1,1-diphosphone, phosphoric acid, phosphonic acid, polyphosphoric acid, metaphosphoric acid, pyrophosphoric acid, and the like. can give.

In the treatment with the phosphorus compound, first, a commercially available anion ion exchange resin is first regenerated with a 5% by weight aqueous sodium hydroxide solution. The SV at this time is preferably 20 Hr ⁻¹ or less.

Then, it is washed with water until the washing solution becomes neutral. Next, it is regenerated with 2 to 5% by weight of a phosphorus compound. The SV at this time is preferably 20 Hr ⁻¹ or less. Wash with water until the water wash is neutral.

  Hydrogen peroxide solution is passed through the cation ion exchange resin or anion ion exchange treated as described above or a mixed bed ion exchange resin of cation ion exchange resin / anion ion exchange resin. The smaller the SV, the better. The liquid temperature at this time is not particularly limited, but usually does not require cooling.

The removal rate of colloidal impurities in hydrogen peroxide water that has been passed through a mixed bed ion exchange resin of cation ion exchange resin, anion ion exchange, cation ion exchange resin / anion ion exchange resin is inversely proportional to SV, and the larger SV is. The removal rate of colloidal impurities decreases. If SV200Hr- ¹ or less, 90% by weight or more is removed.
Although colloidal impurities can be captured by cation ion exchange resin or anion ion exchange resin, the reason is not clear, but colloidal impurities such as Al and Fe are hydroxides and hydrates that do not dissociate into ions in hydrogen peroxide water. It is thought that it is adsorbed and added to an ion exchange resin that is present and slightly negatively charged and has a charge.

In the present invention, (1) ultrafiltration with a ceramic filter, and (2) contact treatment with a cation ion exchange resin or anion ion exchange resin, or a mixed bed ion exchange resin of cation ion exchange resin / anion ion exchange resin are used in combination. May be. The order in the case of using together is not particularly limited. In this way, by using the treatments (1) and (2) in combination, the colloid can be further efficiently removed.

Thus, the pretreated hydrogen peroxide solution is purified using a purification tower or RO membrane filled with an ion exchange resin, a chelate resin or an adsorption resin.
Known ion exchange resins, chelate resins, adsorbent resins, and RO membranes can be used without particular limitation.
[Pretreatment equipment for hydrogen peroxide solution]
In the present invention, a hydrogen peroxide solution containing impurities is contacted with an ion exchange resin, a chelate resin or an adsorption resin using a purification tower packed with an ion exchange resin, a chelate resin or an adsorption resin, and is peroxidized. A purifying apparatus for purifying hydrogen water using a purified hydrogen peroxide solution or an RO membrane,
As a pretreatment means to remove colloidal impurities contained in the raw hydrogen peroxide water,
(i) Circulation tank, circulation pump and ceramic filter and / or
(ii) A pretreatment apparatus including a purification cylinder filled with an ion exchange resin made of a cation ion exchange resin or an anion ion exchange resin.

  FIG. 1 shows a first embodiment of a pretreatment apparatus according to the present invention, which comprises a circulation tank 1, a circulation pump 2, a ceramic filter 3, and a circulation line 4. Further, as shown in the figure, a pressure valve and a discharge port are appropriately provided.

  The raw hydrogen peroxide solution is sent from the circulation tank 1 to the ceramic filter 3 by the pump 2. Hydrogen peroxide is divided into circulating and permeating water. Most of the hydrogen peroxide solution returns to the circulation tank through the hollow part of the ceramic filter. At the same time, some hydrogen peroxide passes through the ceramic filter and is discharged as colloid-free hydrogen peroxide.

  The filtration pressure of the ceramic filter is determined by adjusting the filter hole diameter, pump rotational speed, inlet pressure and outlet pressure. The tank material and the piping material are preferably those that do not corrode or have impurities mixed therein. Typically, Teflon (registered trademark) coated stainless steel or Teflon (registered trademark) lined stainless steel is used. The valve for adjusting the pressure is preferably made of Teflon (registered trademark).

  The filter is made of porous ceramic (hollow type) as described above, and the housing is made of stainless steel coated with Teflon (registered trademark) or stainless steel coated with Teflon (registered trademark). The packing in the apparatus of the present invention is preferably made of Teflon (registered trademark) or Viton.

A second aspect of the pretreatment apparatus is an ion exchange cylinder filled with an ion exchange resin made of a cation ion exchange resin or an anion ion exchange resin.
The raw hydrogen peroxide solution passes through the ion exchange tube and is discharged as colloid-free hydrogen peroxide solution.

  The ion exchange tube may be a column or a cylinder, and the material is preferably Teflon (registered trademark) coated stainless steel, Teflon (registered trademark) lined stainless steel, or Teflon (registered trademark) material such as PFA or PTFE. The ion exchange resin can be regenerated and reused according to reasonable processing methods.

FIG. 2 shows an embodiment of the present invention in the pretreatment apparatus of the present invention, and includes a circulation tank 1, a circulation pump 2, a filter 3, a circulation line 4, and an ion exchange resin purification cylinder.
The raw hydrogen peroxide solution is sent from the circulation tank 1 to the filter 3 by the pump 2. Hydrogen peroxide is divided into circulating and permeating water. As in the first embodiment, most of the hydrogen peroxide solution passes through the hollow portion of the ceramic filter, and further returns to the circulation tank through the ion exchange resin. By doing so, colloidal impurities that have not permeated through the filter can be prevented from being trapped by the ion exchange resin and increasing in the circulation tank. In this case, the ion exchange resin may be an anion ion exchange resin by treatment with a phosphate compound, an H ⁺ type cation ion exchange resin, or a mixture thereof. At the same time, part of the hydrogen peroxide passes through the ceramic filter and is discharged as hydrogen peroxide without colloid. Filtration pressure is determined by adjusting the filter hole diameter, pump speed, inlet pressure and outlet pressure.

The tank material, piping material, valve, filter, housing and packing are the same as described above.
[Example]
EXAMPLES Hereinafter, although an Example demonstrates this invention further, this invention is not limited to these Examples at all.
[Example 1]
After adding 50 ppm (as P) of polyphosphate to colloid-rich 35% by weight raw material hydrogen peroxide (Al concentration 736 ppb) and aging for 1 day,
0 nm porous ceramic filter (membrane area 0.35 m ² ) with inlet pressure 0.17MP
(a) Cross-flow was performed at an outlet pressure of 0.02 MPa and a linear velocity of 4 m / sec, followed by filtration.
The filtration rate was 63 liters / hour.

One liter each of hydrogen peroxide water before and after the treatment was taken and filtered through a disk filter having a pore size of 0.08 μm and 25 mmφ, and the filter cake on the filter was observed by SEM.
SEM photographs before and after the treatment are shown in FIG. From FIG. 3, it was found that a number of minute spherical colloidal impurities are seen in layers before the treatment, but the colloidal impurities are eliminated after the ceramic filter treatment.

The Al concentration before the treatment was 736 ppb, but it decreased to 3 ppb after the treatment.
[Comparative Example 1]
The same colloid-rich 35% weight raw material hydrogen peroxide (Al concentration 736 ppb) is 0.03
Filtration was performed with a μm MF filter (polyolefin, membrane area 1.1 m ² ) at a flow rate of 8 liters / min.

The Al concentration after treatment is 731 ppb, which is the same as before treatment.
[Example 2]
After adding 30 ppm of sodium polyphosphate (as P) to a 35 wt% raw material hydrogen peroxide solution of colloid-rich (Al concentration 875 ppb) and aging for one day,
0 nm porous ceramic filter (membrane area 0.35 m ² ) with inlet pressure 0.17MP
(a) Cross-flow was performed at an outlet pressure of 0.02 MPa and a linear velocity of 4 m / sec, followed by filtration.
The filtration rate was 63 liters / hour.

The space velocity SV = 15Hr ^{− of the} filtered 35 wt% hydrogen peroxide solution in the order of H ⁺ type cation resin column, F ⁻ type anion exchange resin column, HCO ₃ ^2- type anion resin column and H ⁺ type cation resin column. Purify by passing continuously through ¹ . The ion exchange resin is recycled and reused according to a reasonable throughput. Even at the 15th regeneration, the Al concentration of the purified hydrogen peroxide solution was maintained at 1 ppt to 1 ppt or less.
[Comparative Example 2]
H ⁺ type cation resin column, F ^- type anion exchange resin column, HCO ₃ ^2- type, without adding 35% raw material hydrogen peroxide water without adding sodium polyphosphate (as P) and filtering with ceramic filter The anion resin column and the H ⁺ type cation resin column were successively purified at a space velocity of SV = 15Hr ⁻¹ . The ion exchange resin is recycled and reused according to a reasonable throughput. At this time, the purified hydrogen peroxide solution at the fourth regeneration leaked a large Al concentration of 15 ppt. Al leak continued for the fifth time. That is, it was found that Al colloid accumulated in the ion exchange resin and leaked.

An example of one mode of the pretreatment means of the refinement device concerning the present invention is shown. Another example of the pre-processing means of the refiner | purifier concerning this invention is shown. The SEM photograph of the colloidal impurity contained in hydrogen peroxide water before the process in Example 2 of this invention is shown. The SEM photograph of the colloidal impurity contained in hydrogen peroxide water after the process in Example 2 of this invention is shown.

Claims (4)

In a method of purifying a raw material hydrogen peroxide solution containing impurities using a purification tower packed with an ion exchange resin, a chelate resin or an adsorption resin, or a method of purifying using an RO membrane,
As a pretreatment for the purification process,
A method for purifying hydrogen peroxide, comprising adding a chelating agent to a raw material hydrogen peroxide solution, and then filtering through a ceramic filter to remove colloidal impurities contained in the hydrogen peroxide solution. In a method of purifying a raw material hydrogen peroxide solution containing impurities using a purification tower packed with an ion exchange resin, a chelate resin or an adsorption resin, or a method of purifying using an RO membrane,
As a pretreatment for the purification process,
A method for purifying hydrogen peroxide, comprising removing colloidal impurities contained in hydrogen peroxide water with a cation ion exchange resin or an anion ion exchange resin. In a method of purifying a raw material hydrogen peroxide solution containing impurities using a purification tower packed with an ion exchange resin, a chelate resin or an adsorption resin, or a method of purifying using an RO membrane,
As a pretreatment for the purification process,
(i) After adding the chelating agent to the raw hydrogen peroxide solution, filtering the colloidal impurities contained in the hydrogen peroxide solution with a ceramic filter, and
(ii) A method for purifying hydrogen peroxide, comprising removing colloidal impurities contained in the hydrogen peroxide water by a cation ion exchange resin or an anion ion exchange resin. The raw hydrogen peroxide solution containing impurities is brought into contact with the ion exchange resin, chelate resin or adsorption resin using a purification tower packed with ion exchange resin, chelate resin or adsorption resin, and the hydrogen peroxide solution is removed. A purification device for purifying hydrogen peroxide water to be purified or a purification device for purification using an RO membrane,
As a pretreatment means to remove colloidal impurities contained in the raw hydrogen peroxide water,
(i) Circulation tank, circulation pump and ceramic filter and / or
(ii) A purification apparatus for purified hydrogen peroxide, comprising a purification cylinder filled with an ion exchange resin comprising a cation ion exchange resin or an anion ion exchange resin.