JP2608825B2 - Purification method of aqueous hydrogen peroxide solution - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to "phosphoric acid and the like" obtained by extracting a reaction solution prepared by a method of producing hydrogen peroxide by an oxidation and reduction method of anthraquinones (so-called anthraquinone method) with water. Hydrogen peroxide aqueous solution containing a large amount of `` a), contacting with specific activated alumina particles at a relatively low temperature for a specific time to convert phosphoric acid from the aqueous hydrogen peroxide solution without substantially causing decomposition of hydrogen peroxide. The present invention relates to a method for purifying an aqueous hydrogen peroxide solution that can be removed at a high rate.

[0002]

2. Description of the Related Art In general, as a method for producing an aqueous hydrogen peroxide solution, a reaction solution prepared by a method of generating hydrogen peroxide by a method of oxidizing and reducing anthraquinones (so-called anthraquinone method) is extracted with water. In this case, phosphoric acids are often added for various purposes in the above-mentioned production method.

Conventionally, a phosphoric acid component in an aqueous hydrogen peroxide solution,
As a method for removing acid components such as sulfuric acid and acetic acid, for example, as described in JP-B-39-3002, adsorption and removal are performed using an ion exchange resin such as Amberlite (manufactured by Organo Corporation). Although the ion exchange resin method is known, this method can remove acid components such as phosphoric acid, but the ion exchange resin particles themselves are decomposed by hydrogen peroxide and used for several times of regeneration. It was not practical due to the problem that it would not be possible.

[0005] As a method for removing the phosphate ion component in the aqueous hydrogen peroxide solution, a phosphate compound in the aqueous hydrogen peroxide solution is converted to a calcium compound, a barium compound,
U.S. Pat. No. 6,097,087 discloses a precipitation method in which a precipitate such as calcium phosphate is formed by reacting with an alkaline earth metal compound such as a magnesium compound in a basic atmosphere (pH 7 to 8.5), and the precipitate is removed by filtration. No. 366
No. 4812, for example. However, the above-mentioned precipitation method has a problem that hydrogen peroxide is extremely easily decomposed because the reaction solution becomes basic.

Japanese Patent Publication No. 48-41158 discloses a method for stabilizing an aqueous hydrogen peroxide solution by removing trace amounts of metals or organic impurities from the aqueous hydrogen peroxide solution. There is disclosed an adsorption method in which an aqueous hydrogen peroxide solution is brought into contact with activated alumina at a temperature near room temperature for a short period of time of 1 to 5 minutes to adsorb and remove the trace impurities and purify.

However, in the above-mentioned activated alumina adsorption method, there is no specific disclosure of a phosphoric acid component (PO ₄ ) , that is, an aqueous solution of hydrogen peroxide containing an excessive amount of phosphoric acid. Excess phosphorus remaining
When using hydrogen peroxide aqueous solution containing an acid, Li
It was completely unclear whether acid could be removed at high removal rates.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a method for converting hydrogen peroxide substantially using a high-concentration aqueous solution of hydrogen peroxide containing excess phosphoric acid which is used for the various purposes described above. It is an object of the present invention to provide an industrial method capable of removing a phosphoric acid component (PO ₄ ) , that is, phosphoric acid at a high removal rate from the aqueous hydrogen peroxide solution without causing any decomposition. .

[0009]

SUMMARY OF THE INVENTION The present invention relates to a method for converting phosphoric acid to a phosphoric acid component (P) obtained by extracting water from a reaction solution in which hydrogen peroxide has been produced by an anthraquinone oxidation / reduction method.
An aqueous hydrogen peroxide solution containing 50 to 10000 ppm as O ₄ ) , an alumina component containing at least 90% as Al ₂ O ₃ , and a specific surface area of 100 to 600 m ^2.
/ G of activated alumina particles at a temperature of 0 to 50 ° C.
The present invention relates to a method for purifying an aqueous hydrogen peroxide solution, which comprises contacting the aqueous solution for 6 to 500 minutes to remove a phosphoric acid component , that is, phosphoric acid from the aqueous hydrogen peroxide solution.

The aqueous solution of hydrogen peroxide used in the present invention is obtained by extracting water from a reaction solution in which hydrogen peroxide has been produced by an anthraquinone oxidation / reduction method, and, if necessary, removing the organic compound remaining in the extract. The solvent and the like are removed by extraction with an organic solvent, and the extract is obtained by concentrating the extract. Hydrogen peroxide is preferably 20 to 80% by weight, particularly 2% by weight.
5-75 are contained by weight%, further, phosphoric acid phosphate
50~10000ppm as component preferably 100
What is necessary is just to contain about 1000 pppm in excess. Since the purification method of the present invention can be carried out under adsorption conditions with little decomposition of hydrogen peroxide, phosphoric acid is removed from an aqueous hydrogen peroxide solution containing hydrogen peroxide at a high concentration of about 40 to 80% by weight. Can be suitably adopted.

The above-mentioned aqueous solution of hydrogen peroxide contains a trace amount of metal such as iron, manganese, chromium, sodium, calcium, aluminum or its ion at 10 ppm or less, preferably about 1 ppm or less, or 200 ppm or less of organic impurities or the like. , Preferably about 100 ppm or less.

The activated alumina particles used in the purification method of the present invention contain an alumina component in an amount of 90% or more, preferably 95% by weight as Al ₂ O ₃ , and have a specific surface area of 100 to 600 m ² / g, preferably 120 to 500 m ² / g, preferably activated γ-alumina particles. The activated alumina particles have a particle size of 3 to 50 mesh, particularly 4 to 5 mesh.
It is preferably about 30 mesh, more preferably about 5 to 20 mesh.

In the activated alumina particles, iron atoms are 0.1% by weight or less, especially 0.5% by weight or less as Fe ₂ O ₃ , and chromium, copper and nickel atoms are 10 ppm or less, respectively. And the sodium content is Na ₂
"Activated alumina particles containing almost no alkali component" such that O is 0.3% by weight or less, particularly 0.2% by weight or less, and more preferably 0.1% by weight or less reduces decomposition of hydrogen peroxide. It is preferable to set the ratio to a high level so that the adsorptivity of phosphoric acid is at a high level.

If necessary, the activated alumina particles may be washed with water or an aqueous solution of an inorganic acid such as dilute nitric acid, hydrochloric acid, sulfuric acid or the like, particularly an aqueous solution of 0.5 to 5% by weight of nitric acid. It may be one obtained by substantially removing an alkali component such as the surface of the above.

Furthermore, activated alumina particles, the saturation adsorption rate of phosphate <br/> (maximum adsorption / activated alumina particles of phosphoric acid), 2-20% by weight 30 ° C., in particular 3 to 15 wt%
About 5 to 12% by weight, the operation of adsorbing phosphoric acid in a large amount of aqueous hydrogen peroxide can be continuously performed for a long time, and the activated alumina particles in the packed bed of the packed tower can be appropriately treated. It is preferable because it can be reactivated at intervals.

In the purification method of the present invention, the activated alumina particles have a packing density of 500 to 1000 g (active alumina particles) / liter (adsorption tower) for adsorbing and removing phosphoric acid and the like from an aqueous hydrogen peroxide solution. Of the packed portion of the adsorption tower ), particularly preferably about 600 to 900 g / liter, to be used after being filled in the packed portion of the adsorption tower to form an activated alumina particle packed layer.

In the purification method of the present invention, the aqueous hydrogen peroxide solution is mixed with the activated alumina particles at a temperature of 0 to 50 ° C., preferably 5 to 40 ° C. for 6 to 500 minutes, preferably 6 to 200 minutes. The phosphoric acid is adsorbed and removed from the aqueous solution of hydrogen peroxide by contact for 8 minutes, more preferably for 8 to 100 minutes. In the present invention, the decomposition rate of hydrogen peroxide in the aqueous hydrogen peroxide solution tends to decrease as the temperature at the time of adsorption decreases, but the amount of phosphoric acid adsorbed on activated alumina at a low temperature close to 0 ° C. It tends to decrease in adsorption.

In the refining method of the present invention, a batchwise method of dispersing activated alumina particles in an aqueous hydrogen peroxide solution at an appropriate ratio and adsorbing and removing phosphoric acid with stirring can be employed. In this case, the weight ratio between the activated alumina particles and the aqueous hydrogen peroxide solution is preferably about 1/2 to 1/100, particularly preferably about 1/5 to 1/50.

Further, in the purification method of the present invention, the activated alumina particles are filled in the packed portion of the adsorption tower so that the packing density becomes about 500 to 1000 g / l, and an activated alumina particle packed layer is formed. A continuous method of continuously supplying an aqueous solution of hydrogen peroxide to an adsorption tower to adsorb and remove phosphoric acid can also be adopted, and this continuous means is preferable. In this case, the SV value (1 / Hr: supply amount of the aqueous hydrogen peroxide solution / volume of the activated alumina particle layer) is 0.5 to 1
0, particularly preferably about 0.6 to 6, and the time during which the aqueous hydrogen peroxide solution is in contact with the activated alumina particle layer (residence time in the packed layer of the aqueous hydrogen peroxide solution) is 6 to 120 minutes, particularly 10 It is preferably about 100 minutes.

In the present invention, the packed tower may be of any type. For example, a supply port for an aqueous solution of hydrogen peroxide and an outlet for an aqueous solution of hydrogen peroxide from which phosphoric acid or the like has been removed. Is preferably a cylindrical container having activated alumina particles filled at an appropriate packed bed height (L) in the center of the packed tower. It is preferable that a perforated plate is provided at the bottom of the packed bed to support the packed bed of activated alumina particles.

If necessary, the packed column may be provided with about 0 to 4
Cooling means for cooling the high-temperature aqueous hydrogen peroxide solution (for example, a cooling jacket surrounding the periphery of the packed tower, cooling provided in the supply side in the packed tower, so that the adsorption can be performed at a low temperature of 0 ° C.) Pipe etc.) may be installed.

In the present invention, the aqueous hydrogen peroxide solution is preferably used with the packed tower installed vertically, and in this case, the aqueous hydrogen peroxide solution flows from the upper part to the lower part of the packed tower. Or may flow from the lower part of the packed tower to the upper part.

In the present invention, the activated alumina particles having adsorbed phosphoric acid or the like after the above-mentioned purification are 0 to 100.
At a temperature of 0 ° C., especially 0 to 50 ° C., with an aqueous solution (about 0.5 to 20% by weight, especially 1 to 10% by weight) of an alkali metal hydroxide such as caustic soda, potassium hydroxide, etc. By washing three times and, if necessary, further washing with pure water and / or an aqueous solution of an inorganic acid such as nitric acid (about 0.1 to 10% by weight, especially 0.5 to 5% by weight) In addition, the adsorbed phosphoric acid can be removed to easily regenerate the adsorption performance, and can be used again for the adsorption of phosphoric acid from the above-mentioned aqueous hydrogen peroxide solution.

[0024]

EXAMPLE In this example, the hydrogen peroxide solution
Hydrogen oxide concentration is permanganese according to JIS K1463
Perform phosphoric acid component by titration with potassium acid solution(PO
_Four )Is the absorbance of the band peach molybdophosphate
Method [Analytical Chemistry Handbook (Revised 2nd Edition), 208 pages, Publisher: Maru
Good, issue date: February 1978].

The chemical composition and physical properties of the activated alumina particles used in the following Examples are shown in Table 1. In each example, activated alumina particles obtained by washing with a dilute aqueous nitric acid solution (concentration: 5% by weight) were used.

[0026]

[Table 1]

Reference Example 1 A reaction solution in which anthraquinone was oxidized and reduced in the presence of a catalyst to produce hydrogen peroxide was extracted with water containing phosphoric acid to obtain an extract containing hydrogen peroxide. Then, the organic solvent and the like remaining in the extract are removed by organic solvent extraction to purify the extract, and the extract is concentrated to obtain an aqueous solution of hydrogen peroxide [hydrogen peroxide (H ₂ O ₂ ): 60% by weight, phosphoric acid component (PO ₄ ): 442 ppm, other organic / inorganic components: about 200 ppm].

Reference Example 2 In the same manner as in Reference Example 1, except that the conditions such as the amount of phosphoric acid used in the water extraction were changed, the concentration of the phosphoric acid component (PO ₄ ) was 354 ppm. An aqueous hydrogen peroxide solution in which the concentration of hydrogen oxide (H ₂ O ₂ ) was 60% by weight was prepared.

Reference Example 3 In the water extraction of the reaction solution obtained in Reference Example 1, the phosphoric acid component (PO ₄ ) was extracted in the same manner as in Reference Example 1 except that the conditions such as the amount of phosphoric acid were changed. A hydrogen peroxide aqueous solution having a concentration of 463 ppm and a hydrogen peroxide (H ₂ O ₂ ) concentration of 60% by weight was prepared.

Reference Example 4 In the water extraction of the reaction solution obtained in Reference Example 1, the phosphoric acid component (PO ₄ ) was extracted in the same manner as in Reference Example 1 except that the conditions such as the amount of phosphoric acid used were changed. A hydrogen peroxide aqueous solution having a concentration of 386 ppm and a hydrogen peroxide (H ₂ O ₂ ) concentration of 60% by weight was prepared.

Reference Example 5 The same procedure as in Reference Example 1 was carried out except that the conditions such as the amount of phosphoric acid used in the water extraction of the reaction solution obtained in Reference Example 1 were changed, and the conditions for concentration of the extract were partially changed. And hydrogen peroxide (H ₂
An aqueous solution of hydrogen peroxide having a concentration of O ₂ ) of 60% by weight and a concentration of phosphoric acid component (PO ₄ ) of 1740 ppm was prepared.

Examples 1 to 3 As an adsorption tower, a supply port for an aqueous solution of hydrogen peroxide is provided at a lower part, an outlet for discharging an aqueous solution of hydrogen peroxide subjected to adsorption treatment is provided at an upper part, and a cooling jacket is provided around the periphery. Activated alumina particles having an average particle diameter of 3 mm and a specific surface area of 180 m ² / g (A type: Mizusawa Chemical Industries, Ltd.) Activated Alumina R, manufactured by
N, Table 1 shows the approximate composition. Using an adsorption tower in which a packed bed in which 100 milliliters are filled at a packed height (L) of 300 mm (a perforated plate having a large number of holes having a diameter of 1 mm is provided below the packed bed), And the said adsorption tower was connected to the supply means of the hydrogen peroxide aqueous solution, and the collection | recovery container of the adsorption processing liquid, and was installed vertically.

The aqueous solution of hydrogen peroxide obtained in Reference Example 1 was charged into a packed tower having a packed bed (L: 300 mm) of activated alumina particles having a capacity of 100 ml, which was charged with 20 mL of the aqueous solution.
0 ml / hr (Example 1, SV value: 2), 50
0 ml / hr (Example 2, SV value: 5), and 1000 ml / hr (Example 3, SV value: 1)
0), and the adsorption temperature is 30.
° C., and the residence time: 30 minutes, 12 minutes, and at 6 minutes, by performing the adsorption of phosphoric acid for 10 hours to obtain purified phosphoric acid to be adsorbed and removed hydrogen peroxide solution, respectively. Table 2 shows the analysis results of the aqueous hydrogen peroxide solution.

Example 4 Using the aqueous hydrogen peroxide solution obtained in Reference Example 2, the activated alumina particles A were replaced with the activated alumina particles B, and the supply amount and SV value of the aqueous hydrogen peroxide solution are shown in Table 2. Except that, in the same manner as in Example 2, phosphoric acid and the like were adsorbed and removed to obtain a purified aqueous hydrogen peroxide solution. Table 2 shows the analysis results of the purified aqueous hydrogen peroxide solution.

Example 5 Phosphorus was prepared in the same manner as in Example 4 except that the activated alumina particles A were replaced with the activated alumina particles C, and the supply amount of hydrogen peroxide and the SV value were as shown in Table 2. A purified aqueous solution of hydrogen peroxide was obtained by adsorbing and removing acids and the like. Table 2 shows the analysis results of the aqueous hydrogen peroxide solution.

Examples 6 and 7 Except that the aqueous solution of hydrogen peroxide obtained in Reference Example 3 was used and the adsorption temperature was adjusted to 10 ° C., Example 2 (activated alumina particles A) and Example 4 (activated alumina In the same manner as in the particles B), phosphoric acid and the like were adsorbed and removed to obtain purified hydrogen peroxide aqueous solutions. Table 2 shows the analysis results of the aqueous hydrogen peroxide solution.

[0037]

[Table 2]

Example 8 To 39 g of the aqueous hydrogen peroxide solution obtained in Reference Example 4,
2 g of activated alumina particles (A type) similar to those used in Example 1 were added, and while being stirred, the activated alumina particles were dispersed in an aqueous hydrogen peroxide solution.
An aqueous solution of hydrogen peroxide purified by adsorption of phosphoric acid or the like was obtained. Table 3 shows the analysis results of the hydrogen peroxide aqueous solution.

Examples 9 to 10 Example 2 was repeated except that 2 g each of activated alumina particles B (Example 9) and activated alumina particles C (Example 10) shown in Table 1 were used as activated alumina particles. Similarly, a purified aqueous hydrogen peroxide solution was obtained. Table 3 shows the analysis results of the hydrogen peroxide aqueous solution.

Example 11 Phosphoric acid was prepared in the same manner as in Example 11 except that 40 g of the aqueous hydrogen peroxide solution obtained in Reference Example 5 and 2 g of activated alumina particles D were used to adjust the adsorption temperature to 40 ° C. A hydrogen peroxide aqueous solution purified by adsorption was obtained. Table 3 shows the analysis results of the hydrogen peroxide aqueous solution.

Example 12 The activated alumina particles D adsorbed with phosphoric acid or the like used in Example 11 were washed twice with an aqueous solution of caustic soda (5% by weight), then washed with pure water, and further diluted with dilute nitric acid. (2% by weight), and finally washed with pure water to prepare regenerated activated alumina particles D. Example 11 except that the above-mentioned regenerated alumina particles D (regenerated D) were used.
In the same manner as described above, an aqueous solution of hydrogen peroxide purified by adsorption of phosphoric acid or the like was obtained. Table 3 shows the analysis results of the hydrogen peroxide aqueous solution.

[0042]

[Table 3]

[0043]

According to the purification method of the present invention, the aqueous hydrogen peroxide solution containing a large amount of phosphoric acid obtained from the reaction solution produced by the anthraquinone method is used to substantially remove the hydrogen peroxide in the aqueous solution. Phosphoric acid and the like are effectively adsorbed on the activated alumina particles without being decomposed, and as a result,
An aqueous hydrogen peroxide solution from which phosphoric acid has been efficiently removed can be obtained.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-B-48-41158 (JP, B1) JP-B-57-4634 (JP, B2) JP-B 63-26244 (JP, B2)

Claims (1)

(57) [Claims] 1. A reaction solution obtained by producing hydrogen peroxide by an oxidation / reduction method of anthraquinones, which is obtained by water extraction .
Phosphoric acid as phosphoric acid component (PO ₄ ) 50 to 10,000
Aqueous solution of hydrogen peroxide containing
activated alumina particles containing at least 90% as l ₂ O ₃ and having a specific surface area of 100 to 600 m ² / g;
A method for purifying an aqueous hydrogen peroxide solution, comprising contacting at a temperature of 0 to 50 ° C. for 6 to 500 minutes to remove phosphoric acid from the aqueous hydrogen peroxide solution.