JPS6236963B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a fine sodium carbonate hydrogen peroxide adduct (2Na ₂ CO ₃ .3H ₂ O ₂ hereinafter referred to as PC).

It has become increasingly important as an oxygen bleach in recent years.
PC is usually manufactured as a granular product that is easy to handle. One method for providing this granular form is to granulate powdered crystals, and it is desirable to use as fine a powdered PC as possible as the granulation raw material. A method for producing PC by reacting a sodium carbonate solution or a sodium carbonate suspension with an aqueous hydrogen peroxide solution is known, but if one attempts to obtain fine powdered PC by simply carrying out this reaction, the crystals will be fine. As a result, the hydrogen peroxide aqueous solution and sodium carbonate or its aqueous solution supplied to the mother liquor as raw materials are prevented from quickly dispersing into the reaction mother liquor. However, as a result of the local concentration increase, the liquid quality deteriorates further, and batch-type production is required, in which all of the crystallized crystals are separated by filtration, and then the reaction is carried out again, resulting in extremely low production efficiency. Not only are there serious industrial problems such as poor water quality, but the crystals obtained under these conditions have poor dehydration properties, and the separated cake has an extremely high moisture content, making it difficult to carry out industrially. difficult. For this reason, known methods mainly use polyelectrolytes such as polyphosphates or polyacrylates to make the crystals finer or coarser, improving manufacturing operability, and producing PC with good fluidity and wear resistance.
However, the formation of fine crystals has been avoided as it impedes filterability and other problems. However, such coarsened PC is not originally suitable for purposes such as granulation, and even if granulated, the properties such as high dissolution rate and high dispersibility that granulated particles should originally have will not be achieved. Not fully demonstrated. For these reasons, the known methods are unsuitable and cannot be used as industrial methods for producing fine powdered PC.

Therefore, the present inventors have conducted intensive research into a method for manufacturing fine PC with good manufacturing operability, and have found that the desired PC can be easily produced industrially in a slurry state and in a state with good dehydration properties. I found a way to do this and completed it.

That is, the present invention provides a method for crystallizing PC by continuously or intermittently supplying and reacting sodium carbonate and hydrogen peroxide in a mother liquor having a specific composition containing sodium chloride, sodium carbonate, and hydrogen peroxide. ,
Crystallization is achieved by adding and coexisting a specific amount of Mg ⁺⁺ , and by using a limited amount of a silicate compound added to this system as a hydrogen peroxide stabilizer relative to Mg ⁺⁺ . The crystals are denatured and modified,
This invention relates to a method for manufacturing fine PC in a continuous or batch manner with good manufacturing operability.

Conventionally, Mg ⁺⁺ has been used as a stabilizer to further improve the stability of PC by being used in combination with a silicic acid compound added as a stabilizer for PC, and is generally added for this purpose. However, for example, according to JP-A-52-117897, Mg ⁺⁺ is used for the purpose of increasing the hardness of the particles, and in JP-A-53-146996, it is also used for the purpose of improving the free flow properties and anti-wear properties of the particles. It is used. However, these methods are performed in combination with other strong modifiers,
The purpose of use, the method, and the form of the obtained PC are all significantly different from the present invention.

As shown in Examples 2 and 3, the addition and coexistence of Mg ⁺⁺ was found to have a sufficient effect on dehydration of crystals and modification of slurry state, but it is not practical to use it alone as a modifier. It has also been found that in order to have value and use, certain conditions must be met. That is, in order to ensure sufficient stability during storage of PC and to avoid decomposition loss of hydrogen peroxide during production, the coexistence of a silicate compound is essential, and Mg ⁺⁺ alone cannot achieve this purpose. I can't. For this reason, the reaction system is forced to coexist with the addition of silicic acid compounds, but this addition and coexistence significantly inhibits the crystal modification and modification effects of Mg ⁺⁺ , and the quantitative relationship changes. In the end, it is no longer possible to expect the effect to appear at all. In order to avoid such inconveniences and produce fine powder PC with industrial value, it is necessary to satisfy a specific relationship between the two and other reaction crystallization conditions. .

According to the present invention, solid sodium carbonate or an aqueous solution thereof and an aqueous hydrogen peroxide solution are continuously or intermittently supplied into a mother liquor having a controlled composition, and the reaction is carried out while stirring in a reaction vessel, and furthermore, the desired reaction is carried out. PC is crystallized, extracted from the container continuously, intermittently, or in a batch method in which the entire amount is extracted, solid-liquid separation is performed according to a conventional method, and the filtrate is collected immediately or with its composition. After adjustment, in the method of recirculating into the container, the mother liquor composition has a sodium carbonate concentration of 2 to 16% by weight,
The hydrogen peroxide concentration is 0.5 to 5% by weight, the sodium chloride concentration is 5.0 to 25% by weight, preferably 22% by weight or less, and the molar ratio of hydrogen peroxide to sodium carbonate is such that the supplied sodium carbonate is in an aqueous state. It is not particularly limited if it is, but if it is solid, it is 1.3 to 0.2, preferably
Manage to below 0.9. If the molar ratio exceeds the upper limit, particulate coarse PC will be partially formed, which is not desirable. 0.001~ for Mg ⁺⁺ concentration
0.5% by weight, preferably 0.002% by weight or more,
The water-soluble Si concentration is 0.003-0.1% by weight and Mg ⁺⁺
The molar ratio of Si to Si is maintained at 12 or less, preferably 8 or less. The form of sodium carbonate to be supplied can be in the form of an aqueous solution, granules, solid anhydrous powder, or hydrated sodium carbonate, but while an aqueous solution has the advantage of being less likely to produce coarse particulate PC, Since an excessive increase in hydrogen peroxide occurs, the mother liquor must be concentrated or partially discarded when it is recycled.It is advantageous to use solid anhydrous sodium carbonate unless otherwise desired, and the concentration of hydrogen peroxide supplied must be It is necessary to select and use so as not to cause fluctuations in quantity.
Generally, it is desirable to use a 40% to 80% by weight aqueous hydrogen peroxide solution.

In addition, for the present invention, reacting sodium chloride,
Adding and coexisting in the crystallization system is an important requirement. This is because industrial PC production is usually carried out in the presence of a large excess of mother liquor, so the absolute amount of PC dissolved in the mother liquor is large, and the decomposition loss during production is an extremely large waste for industrial use. However, by coexisting sodium chloride, the concentration of PC in the mother liquor decreases, and it is ineffectively decomposed and lost during the reaction or when the filtered mother liquor is recycled and used. This is because the absolute loss of the hydrogen peroxide component caused by chlorination is greatly reduced, the amount of expensive hydrogen peroxide used can be reduced, and an industrially advantageous system can be created. Sodium concentration is 5.0-25% by weight, preferably 22% by weight
It is as follows. The supply of Mg ⁺⁺ is not particularly limited as long as it is a magnesium compound that substantially provides Mg ⁺⁺ and is inactive against the decomposition of hydrogen peroxide, but generally magnesium sulfate, magnesium chloride, etc. Such a water-soluble magnesium salt is dissolved in an aqueous solution or an aqueous hydrogen peroxide solution and added continuously or intermittently to the reaction mother liquor.

In order to obtain a sufficient effect for modifying the crystals and improving the slurry state and dehydration properties, the amount of Mg ⁺⁺ added must be adjusted in terms of weight ratio to the supplied sodium carbonate.
Mg ⁺⁺ /Na ₂ CO ₃ = 0.01/100 to 1/100 preferably
0.02/100 or more, and this addition causes the PC crystals to change from a needle-like shape to a plate-like shape, including intermediate shapes, and the crystals between crystals are the main cause of the slurry state and deterioration of water increase. As a result of the disentangling, the slurry condition and dewatering properties are greatly improved. However, as is well known, in order to make the stability of PC sufficient for practical use, it is essential to add a silicate compound as a stabilizer, and although the stability is improved by this addition, the above-mentioned Mg ⁺⁺ The modification effect is significantly inhibited. Therefore, the amount of the silicic acid compound added must be within a limited range in relation to the amount of Mg ⁺⁺ added, and the amount must be such that the produced PC has sufficient stability for practical use. The amount of silicic acid compound supplied for this purpose is expressed as water-soluble Si/Si/
Na ₂ CO ₃ = 0.02/100 to 0.5/100 preferably,
0.04/100 to 0.2/100, and the molar ratio of Si/Mg ⁺⁺ to Mg ⁺⁺ must be 2.5 or less, preferably 1.0 or less.

As the silicate compound, known stabilizers such as water glass, various water-soluble sodium silicates such as sodium metasilicate, magnesium silicate, or colloidal silica can be used.
For difficult or insoluble silicic acid compounds, most of the added silicic acid compounds are suspended in the mother liquor in a substantially insoluble state, so the above values are not absolute amounts, but are based on the amount dissolved in water or substantially in the mother liquor. It should be understood that the part that dissolves in These silicic acid compounds are usually fed continuously or intermittently as an aqueous solution into the reaction mother liquor or into the circulated mother liquor.

Sodium carbonate, hydrogen peroxide, sodium chloride, Mg ⁺⁺ , and a silicate compound are fed into the reaction vessel while adjusting the composition of each component in the mother liquor to be within the range to be maintained.

Sodium carbonate and hydrogen peroxide supplied by the above method react in the mother liquor and crystallize and grow as PC, but if the supply rate of raw materials exceeds the crystallization rate of crystals, Since a highly supersaturated system is transiently formed, the crystals rapidly precipitate into dominant needle-like crystals, making it impossible to achieve the purpose. For this reason, the feed rate of sodium carbonate, which is continuously or intermittently fed, is preferably such that the weight ratio of Na ₂ CO ₃ /mother liquor is 50/100 or less, preferably 30/100 or less, per unit time. , and obtained a sufficient crystallization rate for modified crystals,
In order to avoid the formation of an excessively supersaturated system, it is preferable that the crystals suspended in the mother liquor have a sufficient surface area and that the crystals are grown in an amount corresponding to the amount of crystallization. From this point of view, it is generally advantageous to have a large amount of PC in the mother liquor, but if it is too large, physical stimulation due to friction between crystals will also increase, making it easier to induce the formation of needle-like crystals. Therefore, it is preferable to draw out the slurry from the reaction vessel so that its concentration is adjusted to 200 g/~400 g/. In continuous reaction crystallization, in order to obtain crystals with a constantly stable particle size, it is necessary to constantly generate new crystal nuclei, but this depends not only on the degree of supersaturation but also on various other factors. Therefore, it is not always easy to control it because it is greatly affected. Therefore, when carrying out the present invention, for the purpose of reducing the influence of supersaturation degree and controlling the grain size and size of crystals over a somewhat wide range, it is necessary to supply fine PC as a seed crystal to the reaction crystallization system. By performing the inoculation method, the grain size or size of the crystals can be controlled more reliably.

The seed crystals used for this purpose are preferably plate-shaped crystals that have been pulverized by a conventional method such as a dry or wet method, and are placed in a reaction vessel as a powder or suspended in a circulating mother liquor. Alternatively, a portion of the reaction slurry may be wet-pulverized as it is and circulated within the reaction vessel. The amount of seed crystals used is not particularly limited depending on the desired crystal grain size, etc., but since using a large amount leads to a decrease in production efficiency, it is generally twice the weight ratio of the sodium carbonate to be supplied. It is desirable to use the amount less than 0.5 times the amount, preferably less than 0.5 times the amount.

Feed rate of raw materials, amount of slurry in the reaction vessel,
The average residence time of crystals, which is determined from slurry concentration, slurry withdrawal speed, etc., is important as a comprehensive consideration of various conditions. Not only is the quality adversely affected, but also the complete progress of the reaction is inhibited, especially when the sodium carbonate is fed in solid form. For this reason, it is theoretically desirable for the residence time to be long, but this is not advantageous industrially because it leads to a decrease in production efficiency per unit time or reactor capacity, and in this sense there is an upper limit. has. In the present invention, the residence time is 20 minutes to 4 hours, preferably 40 minutes or more.

The liquid temperature at the stage of reaction crystallization is 10℃~
Cooling is carried out as necessary to maintain the temperature at 40°C, preferably 15 to 30°C, but if it exceeds 40°C, it is undesirable because it will cause a significant loss of hydrogen peroxide.On the other hand, if it is too low, If the supplied sodium carbonate is solid, it is difficult to completely dissolve the raw material in the reaction vessel, and the reaction is insufficient and the sodium carbonate is discharged.

Therefore, the temperature at this stage must be maintained at a necessary and sufficient temperature. However, since PC exhibits high solubility at high temperatures, the hydrogen peroxide concentration in the mother liquor inevitably increases at high temperatures, increasing hydrogen peroxide loss per unit volume of mother liquor. In order to avoid such inconveniences, the reaction temperature should be kept at the lowest temperature necessary for complete reaction, and if desired, the slurry drawn out after the reaction may be cooled secondarily and dissolved in the mother liquor. Further crystallize the PC that is
It is advantageous to take measures such as reducing the hydrogen peroxide concentration. According to this method, less than 300 microns
Easy to obtain fine powder crystals of 85 to 98%, 45 to 80% of 150 microns or less, and further obtain fine powder crystals of 85 to 100% of 300 microns or less, 45 to 85% of 150 microns or less. PC is suitable as a raw material for granulation and other purposes.

When carrying out this method, in addition to the silicic acid compound, known stabilizers such as phosphorus compounds such as sodium pyrophosphate and sodium tripolyphosphate, or organic chelating agents such as EDTA may be used in combination to further improve stability. However, the stabilizing effect of these is essentially based on the complexation and sequestration of the metal, which also partially sequesters Mg ⁺⁺ and reduces the effect of Mg ⁺⁺ . Therefore, when these are used in combination in this method, it is desirable to increase the amount of Mg ⁺⁺ added and coexisting in accordance with the combined amount and the Mg ⁺⁺ sequestering ability. Furthermore, when carrying out this method, known crystal modifiers such as polyelectrolytes such as sodium hexametaphosphate and sodium polyacrylate may be used together, but their addition is not recommended in this method unless specifically desired. Not needed at all.

The present invention will be explained below using examples.

Example 1 A mother liquor 30 having a composition of 5.1% by weight of sodium carbonate, 1.0% by weight of hydrogen peroxide, 17.0% by weight of sodium chloride, 0.007% by weight of Mg ⁺⁺ , and 0.004% by weight of Si was placed in a reaction vessel with a diameter of 40 cm. Stir at a speed of 130 rpm using a 22 cm stirring blade, and keep the liquid temperature at 25°C.
Granular anhydrous sodium carbonate while maintaining at 6.0
Kg/Hr., 60 wt% hydrogen peroxide 4.97 Kg/Hr., sodium chloride 497 g/Hr., 20.0 wt% MgSO ₄ aqueous solution 120 g/Hr., 20.0 wt% sodium silicate solution 100 g/Hr. feed into the reaction vessel at a continuous rate. One hour after the start of the reaction, the slurry (slurry concentration 244 g/) was extracted and centrifuged at 1200 G for 2 minutes. The moisture content of the cake was 16.8%, and the particle size of the obtained PC was 300 μ or less, 97.4% by weight.
150μ or less is 81.1% by weight, and the effective oxygen content is
13.8% by weight, and the impurity content is NaCl and
Na ₂ CO ₃ 3.9 wt% and 5.5 wt% respectively
It was hot. In addition, in this method, the addition amount ratio of Mg ⁺⁺ to the Na ₂ CO ₃ supply amount (Mg ⁺⁺ /Na ₂ CO ₃ ) is 0.081% by weight, which indicates that the water-soluble
Addition ratio of Si to Na ₂ CO ₃ supply (Si/
Na ₂ CO ₃ ) is 0.009% by weight, and the added Si
The molar ratio (Si/Mg ⁺⁺ ) to Mg ⁺⁺ is 0.485, and Mg ⁺⁺ in the mother liquor
The molar ratio of hydrogen peroxide and Si (Mg ⁺⁺ /Si) ranges from 0.4 _to 0.9, and the molar ratio of hydrogen peroxide to _sodium carbonate ( _H2O2 / _Na2CO3 ) in the mother liquor ranges from 0.5 to 0.8. It was within the range of

Example 2 Using a mother liquor having a composition of 5.1% by weight of sodium carbonate, 1.0% by weight of hydrogen peroxide, 17.0% by weight of sodium chloride, 0.013% by weight of Mg ⁺⁺ , and 0.007% by weight of Si,
Furthermore, 230g/Hr. of 20.0% by weight MgSO ₄ aqueous solution was added.
The reaction was carried out under the same conditions as in Example 1, except that it was continuously fed at a rate of . One hour after the start of the reaction, the slurry (slurry concentration 243 g/) was extracted,
The moisture content of the cake centrifuged at 1200G for 2 minutes is
14.5%, and the particle size of the obtained PC is less than 300μ
97.7% by weight, 83.4% by weight below 150μ, the effective oxygen content is 14.3% by weight, and the impurity content is
NaCl _{and Na2CO3} at 3.3 wt% and
It was 2.7% by weight. In addition, Mg ⁺⁺ in this method
The addition amount ratio (Mg ⁺⁺ /Na ₂ CO ₃ ) to the Na ₂ CO ₃ supply amount is 0.155% by weight, and the water-soluble
The ratio of the amount of Si added to the amount of Na ₂ CO ₃ supplied (Si/Na ₂ CO ₃ ) is 0.009% by weight, and the amount of Si added is 0.009% by weight.
The molar ratio of Si to Mg ⁺⁺ (Si/Mg ⁺⁺ ) is 0.253, and Mg ⁺⁺ in the mother liquor
The molar ratio of hydrogen peroxide and Si (Mg ⁺⁺ /Si) ranges from 0.3 _to 0.7, and the molar ratio of hydrogen peroxide to _sodium carbonate ( _H2O2 / _Na2CO3 ) in the mother liquor ranges from 0.5 to 0.8. It was within the range of

Comparative Example 1 Sodium carbonate 5.1% by weight, hydrogen peroxide 1.0% by weight, sodium chloride 17.0% by weight, Si 0.003% by weight
The reaction was carried out under the same conditions as in Example 1, except that a mother liquor having the composition was used and no Mg ⁺⁺ was added. The viscosity of the slurry increased 10 minutes after the start of the reaction, and 20 minutes later, the supplied sodium carbonate was not dispersed below the liquid surface and solidified above the liquid surface.
It was impossible to continue the reaction any further. Next, this slurry (slurry concentration 89 g/) was taken out from the container and centrifugally dehydrated at 1200G for 2 minutes.
The particle size is 81.2% by weight below 300μ, 68.3% by weight below 150μ, the available oxygen content is _12.9 % by weight, and the impurity content is _7.1 % by weight and 7.1% by weight, respectively.
It was 8.2% by weight. In addition, Mg ⁺⁺ in this method
The addition amount ratio (Mg ⁺⁺ /Na ₂ CO ₃ ) to the Na ₂ CO ₃ supply amount is 0% by weight, and the water-soluble Si
The addition amount ratio (Si/Na ₂ CO ₃ ) to the Na ₂ CO ₃ supply amount is 0.009% by weight, and the molar ratio of hydrogen peroxide to sodium carbonate in the mother liquor (H ₂ O ₂ /Na ₂ CO ₃ ) ranged from 0.5 to 0.8.

Example 3 A mother liquor 30 having a composition of 5.1% by weight of sodium carbonate, 0.8% by weight of hydrogen peroxide, 17.0% by weight of sodium chloride, 0.013% by weight of Mg ⁺⁺ , and 0.008% by weight of Si was placed in a reaction vessel with a diameter of 40 cm. While maintaining the liquid temperature at 25℃ by stirring at a speed of 100r.pm using a 22cm stirring blade, 6.0Kg of granular anhydrous sodium carbonate/
Hr.60wt% hydrogen peroxide 4.97Kg/Hr., sodium chloride 500g/Hr, 20.0wt% _MgSO4 aqueous solution
170g/Hr., 50% by weight of No. 3 sodium silicate
The aqueous solution was continuously added to the reaction vessel at a rate of 72 g/Hr., and the reaction mother liquor composition was 5.0 to 7.0% by weight for sodium carbonate and 0.8 to 1.3% for hydrogen peroxide.
% by weight, sodium chloride is supplied while adjusting the concentration to be 16 to 17% by weight, and the slurry is continuously extracted from the container so that the slurry concentration in the reaction container is maintained at 280 g/L, and centrifuged to remove crystals. Continuous reaction crystallization was performed by separating the filtrate and circulating the filtrate within the reactor. The dehydrated cake obtained after 4 hours had a water content of 15.1%, the crystals after drying were 93.7% below 300 microns, 57.2% below 150 microns, and the effective oxygen content was
14.5% by weight, and the impurity content is NaCl and
Na ₂ CO ₃ 3.5 wt% and 1.3 wt% respectively
It was hot. In addition, in this method, the addition amount ratio of Mg ⁺⁺ to the Na ₂ CO ₃ supply amount (Mg ⁺⁺ /Na ₂ CO ₃ ) is 0.114% by weight, which indicates that the water-soluble
Addition ratio of Si to Na ₂ CO ₃ supply (Si/
Na ₂ CO ₃ ) is 0.081% by weight, and the amount of Si added is 0.081% by weight.
The molar ratio (Si/Mg ⁺⁺ ) to Mg ⁺⁺ is 0.616, and the Mg ⁺⁺ in the mother liquor
The molar ratio of hydrogen peroxide to _sodium carbonate ( ^H2O2 / _Na2CO3 ) in _the mother liquor ranges from 0.4 to _0.7 . It was within the range of

Example 4 Using a mother liquor having a composition of 5.0% by weight of sodium carbonate, 0.4% by weight of hydrogen peroxide, 21.5% by weight of sodium chloride, 0.015% by weight of Mg ⁺⁺ , and 0.008% by weight of Si,
While maintaining the liquid temperature at 25℃, granular anhydrous sodium carbonate 6.0Kg/Hr., 60% by weight, hydrogen peroxide 5.0Kg/Hr.
Hr., sodium chloride 710g/Hr, 20.0% by weight
MgSO ₄ aqueous solution 190 g/Hr. and No. 3 sodium silicate 50 wt% aqueous solution 72 g/Hr. The slurry concentration was controlled to be 1.0% by weight, 20-22% by weight of sodium chloride, and a part of the wet cake separated by filtration was mixed with the filtrate at a ratio of 1:1, wet-pulverized, and placed in a reaction vessel. Continuous inoculations were carried out within the same period.

The amount of seed crystals was determined as dry weight at a ratio of 100:15 to the weight of sodium carbonate supplied. After 4 hours of continuous reaction, the cake was dehydrated at 1200G for 2 minutes.
It has a water content of 10.7%, the crystals after drying are 99.3% below 300 microns, 77.6% below 150 microns, the effective oxygen content is 14.4% by weight, and the impurity content is NaCl and _{Na2CO3 .} , were 3.0% and 2.2% by weight, respectively. In addition, in this method, the addition amount ratio of Mg ⁺⁺ to the Na ₂ CO ₃ supply amount (Mg ⁺⁺ /Na ₂ CO ₃ ) is 0.128% by weight, which indicates that the water-soluble
Addition ratio of Si to Na ₂ CO ₃ supply (Si/
Na ₂ CO ₃ ) is 0.081% by weight, and the amount of Si added is 0.081% by weight.
The molar ratio (Si/Mg ⁺⁺ ) to Mg ⁺⁺ is 0.551, and Mg ⁺⁺ in the mother liquor
and Si (Mg ⁺⁺ /Si) ranges from 0.5 _to 1.5, and the molar ratio of hydrogen peroxide to _sodium carbonate ( _H2O2 / _Na2CO3 ) in the mother liquor ranges from 0.3 to 0.7. It was within the range of

Claims (1)

[Claims] 1. Sodium carbonate and hydrogen peroxide are continuously or intermittently supplied to the mother liquor, and reaction and crystallization are carried out under the following conditions in an aqueous solution containing sodium chloride, sodium carbonate, and hydrogen peroxide. A method for producing a fine sodium carbonate hydrogen peroxide adduct, which is characterized by obtaining fine crystals by analysis. Mother liquor composition is 2 for sodium carbonate concentration.
~16% by weight, 0.4-5 for hydrogen peroxide concentration
5.0-25 for weight%, sodium chloride concentration
wt%, 0.001-0.5 wt% for Mg ⁺⁺ concentration, 0.003-0.1 wt% for Si concentration,
And the molar ratio of Si to Mg ⁺⁺ is maintained at 12 or less. Mg ⁺⁺ is added at a weight ratio of Mg ⁺⁺ / _Na2CO3 =0.01/100 to 1/100 to _the sodium carbonate to be supplied. Using silicate or silicic acid as a stabilizer, water-soluble Si is added in weight ratio to sodium carbonate to be supplied.
Add at a ratio of 0.02/100 to 0.5/100 as
In addition, the molar ratio to added Mg ⁺⁺ is 2.5 or less. 2 The particle size of the sodium carbonate hydrogen peroxide adduct produced is 300μ or less 85-100%, 150μ or less 45-85%
The manufacturing method according to claim 1. 3. When carrying out the reaction and crystallization, a fine sodium carbonate hydrogen peroxide adduct is supplied and inoculated at a weight ratio of 1/2 or less to the sodium carbonate to be supplied. Manufacturing method described in section. 4. The production method according to claim 1, characterized in that after the produced sodium carbonate hydrogen peroxide adduct is filtered and separated from the mother liquor, the filtrate is recycled.