JP3308303B2 - Continuous production method of amorphous aluminosilicate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for continuously producing an amorphous aluminosilicate, and more particularly, to an inexpensive, highly oil-absorbing, highly ion-exchangeable, and solid-liquid separation reaction slurry. The present invention relates to a method for continuously producing amorphous aluminosilicate, which is characterized by high speed and easy solid-liquid separation.

[0002]

2. Description of the Related Art As a highly oil-absorbing inorganic carrier, amorphous hydrated silica called white carbon has been known. Many uses have been developed, such as fillers and papermaking. However, amorphous hydrous silica has a negative surface potential, and when used as, for example, a filler for papermaking, it repels the negative surface potential of pulp, and its yield is unfavorable. In addition, amorphous hydrated silica has a high porosity, a surface hydroxyl group, and contains a large amount of adsorbed water.
It also has a lower refractive index than other general silicas, and is disadvantageous in maintaining the opacity of the paper after printing.

As a highly oil-absorbing inorganic carrier, dry silica called aerosil is known, and is used as a filler for rubber and plastics. It is not suitable for use in fields where inexpensive raw materials are required, such as the paper industry. Also,
Petal calcium silicate powder marketed under the trade name "Florite" is 500-600 ml / 100 g
However, it is expensive and has drawbacks such as causing pitch trouble when used for papermaking.

[0004] In addition to the above-mentioned disadvantages, these highly oil-absorbing inorganic carriers have a disadvantage that they do not have an ion-exchange ability, and are used in applications requiring a water softening effect, for example, detergent builders and agricultural chemical carriers. Or, it is not suitable for use for preventing scale generation due to ionic impurities such as Ca and Mg ions.

[0005] As a substance having a high ion exchange capacity, crystalline aluminosilicate called zeolite is well known. In particular, synthetic zeolite type 4A is actually used in large quantities as a builder for synthetic detergents. . However, zeolite itself is a densely packed crystal particle of 1 to 10 μm, and although it has many holes of molecular order, the retention of macroscopic voids related to oil absorption is extremely small, and its oil absorption is at most. It is about 60 ml / 100 g, cannot be expected to have high dispersibility in oil or water, and cannot be used for applications requiring high oil absorption. Amorphous aluminosilicate powder marketed under the trade name "Zeolex" has similar uses as white carbon and the like, but has low oil absorption and ion exchange capacity.

On the other hand, various methods for continuously producing an amorphous (amorphous) aluminosilicate have been studied. For example, according to "Continuous production method of granular amorphous aluminosilicate" in JP-A-57-61613, an aqueous alkali aluminate solution is continuously supplied to a first-stage reaction tank, and an aqueous alkali silicate solution is supplied. Although a method of split supply to a plurality of reaction vessels including the first stage is shown,
The aluminosilicate obtained by this method had a low oil absorption capacity and the filtration speed in solid-liquid separation was not satisfactory. Furthermore, Japanese Patent Application Laid-Open No. 55-140713 discloses a "continuous production method of an alkaline aqueous suspension of fine-grained sodium aluminosilicate amorphous by X-ray diffraction". This is a method in which an aqueous alkali solution is continuously supplied to a first-stage reaction vessel, and an aqueous alkali silicate solution is dividedly supplied to a plurality of reaction vessels including the first-stage reaction vessel. The aluminosilicate obtained by this method also has a low oil absorbing ability, and the filtration speed in solid-liquid separation was not satisfactory.

[0007] Accordingly, an object of the present invention is to provide a high oil absorption capacity of at least 150 ml / 100 g or more at a low cost.
Amorphous aluminosilicate with high ion exchange capacity of at least mg CaCO ₃ / g and very high filtration rate in the solid-liquid separation process for removing the product from the reaction slurry To provide a manufacturing method.

[0008]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the problems of the prior art as described above, and as a result, have a high oil absorption capacity and a high ion exchange capacity.
The present inventors have found a method for continuously producing an amorphous aluminosilicate having a very high filtration rate of a reaction slurry, and have completed the present invention.

That is, according to the present invention, an alkali metal aluminate and an alkali metal silicate are reacted at a temperature of 10 to 100 ° C. in the presence of an alkali metal salt and / or an alkaline earth metal salt. The solution to be used has a molar ratio of 0.5 to 8 M _x O: Al ₂ O ₃ : 1 to 7 SiO ₂ : 50 to 1500 H ₂ O (where M represents an alkali metal, an alkaline earth metal or a mixture thereof, and x represents 1 or 2. A method for continuously producing an amorphous aluminosilicate by having a composition represented by the formula (2), wherein an alkali metal salt and / or
Alternatively, alkaline earth metal salts, alkali metal aluminates, and alkali metal silicates are continuously injected, and at least one of them is continuously injected into a plurality of locations in the reactor. It is intended to provide a continuous method for producing an amorphous aluminosilicate, which comprises reacting, depositing and separating an amorphous aluminosilicate.

The raw materials for continuously producing the amorphous aluminosilicate of the present invention having the characteristics of high oil absorption and high ion exchange capacity and very high filtration rate are: (a) an aqueous alkali metal aluminate salt solution; (B) an aqueous solution of an alkali metal silicate, and (c) an alkali metal salt and / or an alkaline earth metal salt. In the present invention, an alkali metal belongs to Group IA of the periodic table, and an alkaline earth metal belongs to Group IIA of the periodic table. These can be used as a mixture of two or more types. , Usually sodium is preferred.

Next, (a) an aqueous solution of an alkali metal aluminate, (b) an aqueous solution of an alkali metal silicate used in the present invention,
(c) An alkali metal salt and / or an alkaline earth metal salt, and (d) an inorganic acid, an organic acid, and an acid salt will be described. (a) Aqueous alkali metal aluminate aqueous solution Commercially available alkali metal aluminate aqueous solution may be used, but an aluminum source (usually aluminum hydroxide) such as aluminum hydroxide or activated alumina is heated and dissolved with alkali hydroxide. Then, a high concentration and low alkali aqueous solution of alkali metal aluminate is first prepared. In this case, the preparation of the high-concentration solution is stabilized by heating and dissolving the aluminum source with alkali hydroxide and then quenching, but it is desirable to prepare a necessary amount of a lower alkali solution each time. For the alkali metal aluminates aqueous solution used in the present invention, the molar ratio of M _x O and Al ₂ O ₃ is M _x O
/ Al ₂ O ₃ = 0.5 to 6.0
The range of ~ 3.0 is particularly preferred. Hereinafter, the aqueous solution of the alkali metal aluminate is abbreviated as solution (a).

[0012] (b) an alkali metal salt aqueous alkali metal silicate solution silicate may be commercially available, but the molar ratio of SiO ₂ and M _x O is _{SiO 2 / M x O = 1.0} ~4.0
It is desirable to use those in the range. As M _x O
Na ₂ O is usually used. Hereinafter, the aqueous solution of the alkali metal silicate is abbreviated as solution (b).

These liquids (a) and (b) are water, alkaline water (for example, aqueous solutions of NaOH, KOH, Ca (OH) ₂ , LiOH, etc.),
An aqueous solution of an alkali metal salt and / or an alkaline earth metal salt can be used after adjusting to an appropriate molar ratio and concentration.

(C) Alkali metal salt and / or alkaline earth metal salt As the alkali metal and alkaline earth metal, Periodic Table IA
Group, group IIA, potassium, sodium, lithium, magnesium, calcium, barium and the like, and as salts thereof, K ₂ CO ₃ , KCl, K ₂ SO ₄ , CH ₃ COOK, Na ₂ C
O ₃ , NaHCO ₃ , NaCl, Na ₂ SO ₄ , CH ₃ COONa, CaCl ₂ , Ca (NO ₃ )
₂ , (CH ₃ COO) ₂ Ca ・ H ₂ O, Li ₂ SO ₄・ H ₂ O, LiCl, BaCl ₂ , MgC
l ₂ , MgSO ₄ , C ₆ H ₅ Na ₃ O _{7 and the} like, but are not limited thereto, and may be prepared from a mixture of two or more of these. Hereinafter, the aqueous solution of an alkali metal salt and / or an alkaline earth metal salt is abbreviated as an aqueous solution of an alkali salt.

(D) Inorganic acids, organic acids, and acid salts Examples of the inorganic acids include sulfuric acid, hydrochloric acid, nitric acid, carbonic acid (CO ₂ ), and phosphoric acid, and the organic acids include formic acid, acetic acid, butyric acid, and caproic acid. , Acrylic acid, oxalic acid, succinic acid, adipic acid,
Benzoic acid, citric acid and the like. The acidic salt is a salt of the inorganic acid or the organic acid, for example, incompletely neutralized salts such as sodium phosphate, sodium citrate, sodium succinate and the like, but are not limited thereto. One type or a mixture of two or more types may be used.

Hereinafter, the reaction method of the present invention will be described in detail. The composition of to be the reaction solution, relative to Al ₂ O ₃ 1 mol of the molar ratio, SiO ₂ is 1 to 7 mol. Preferably it is 2 to 6 mol. If SiO ₂ is less than 1 mol, Al ₂ O ₃ remains unreacted in the product and adversely affects it. If the amount of SiO ₂ is more than 7 mol, the SiO ₂ remains unreacted in the product and adversely affects it. The molar ratio of M _x O supplied from solution (a), solution (b) and alkali water is 0.5 to 1 mol of Al ₂ O _3.
８8 mol, preferably 1-5 mol. If the amount is less than 0.5 mol, the reaction becomes insufficient. If the amount is more than 8 mol, crystallization proceeds, and it becomes difficult to obtain the desired amorphous aluminosilicate, and it becomes difficult to recover excess alkali. The molar ratio of H ₂ O is 50 to 1 mole of Al ₂ O _3.
モ ル 1500 mol, preferably 100-1300 mol.
If the amount is less than 50 mol, the concentration of the reaction system becomes high, and crystallization proceeds, making it difficult to obtain amorphous aluminosilicate.
If it is more than 1500 moles, the system concentration is too low, and the production efficiency is greatly reduced.

The present invention is based on the principle that the respective aqueous solutions are continuously supplied to the reaction system and reacted using a continuous reactor. Examples of the reaction equipment include, but are not limited to, a multistage reactor type reactor having at least two or more reaction vessels as shown in FIG. 1 and a tubular reactor as shown in FIGS. 2 and 3. Not something. Examples of the method of dropping the raw material and the reaction method include various methods as shown below, but are not limited thereto.

1. An aqueous solution of an alkali salt as a reaction raw material,
A method in which the (a) liquid, the (b) liquid, and, if necessary, water and alkaline water are each dropped at a predetermined ratio to each reaction tank. 2. Supply the aqueous alkali salt solution and solution (a) (two solutions may be mixed in advance) only to the first-stage reaction tank, and add the solution (b),
If necessary, add water and alkaline water to each stage reaction tank,
A method of dropping at a predetermined ratio. 3. Supply the aqueous alkali salt solution and the liquid (b) (or two liquids may be mixed in advance) only to the first-stage reaction tank, and add the liquid (a),
If necessary, add water and alkaline water to each stage reaction tank,
A method of dropping at a predetermined ratio. 4. Pre-react the alkaline salt aqueous solution with the solution (a) and the solution (b) at a predetermined ratio, supply this to the first reaction tank, and transfer the remaining raw materials to the reaction tanks including the first step. A method in which water and alkaline water are respectively dropped at a predetermined ratio into each reaction tank according to the conditions.

FIG. 1 shows an example of a multistage reactor type reactor suitable for carrying out the present invention. Hereinafter, the present invention will be described with reference to FIG. 1, but the present invention is not limited thereto. First, as a method for preparing an aqueous solution of an alkali salt, a filtrate obtained by neutralizing and filtering a reaction slurry or a filtrate of the reaction slurry with an inorganic or organic acid such as hydrochloric acid, sulfuric acid, carbonic acid, or citric acid (hereinafter referred to as a mother liquor) Abbreviated) can be used. On the other hand, as one method for preparing from water, sodium chloride, sodium sulfate, sodium carbonate, sodium citrate, sodium acetate, calcium chloride and the like can be dissolved and used. The salt concentration of the aqueous alkali salt solution is preferably from 0.05 to 25% by weight (hereinafter simply referred to as%), more preferably from 2 to 12%, based on the reaction system.
When the salt concentration is lower than 0.05%, the filtration rate is low, and when the salt concentration is higher than 25%, the completion of the reaction is inhibited.

The aqueous solution of the alkali salt and the three liquids (a) and (b) are continuously added to the reaction vessel A. The average residence time in reactor A is from 5 seconds to 30 minutes, preferably from 20 seconds to 5 minutes. The reaction temperature is 10-100 ° C, preferably 20-65.
Temperature. Further, the M _x O concentration in the reaction tank A 0.1 to 5%,
Desirably, the addition amounts of the three solutions (a), (b) and the aqueous solution of an alkali salt are adjusted so as to be 0.1 to 2.5%.

In the reaction tank B, an aqueous solution of an alkali salt and the solution (a) are added to the reaction solution (hereinafter abbreviated as reaction solution A) flowing from the reaction tank A in an amount of 0 to 50%, preferably 0 to 20% of the total amount used. I do.
Further, the solution (b) is used in an amount of 5 to 50% of the total amount, preferably 10 to 40%.
%Added. Further, by adjusting the alkali concentration and solid concentration of the reaction system of the reaction tank B by adding alkaline water and water, a high-performance amorphous aluminosilicate can be reacted. Also in the reaction tank C, an aqueous solution of an alkali salt and the solution (a) are added to a reaction solution (hereinafter abbreviated as reaction solution B) flowing from the reaction tank B in an amount of 0 to 50%, preferably 0 to 20% of the total amount used.
Further, the solution (b) is used in an amount of 5 to 50% of the total amount, preferably 10 to 40%.
%Added. Further, the alkali concentration and the solid content concentration of the reaction system of the reaction tank C can be adjusted by adding alkaline water and water dropwise. In this way, the reaction is carried out in multiple stages in this manner.

The higher the reaction temperature, the higher the ion exchange capacity. However, when it is too high, the oil absorption capacity of the obtained amorphous aluminosilicate decreases. The reaction temperature is preferably in the range of 10 to 100 ° C., particularly preferably in the range of 20 to 65 ° C., in order to obtain those having both high physical properties. The concentration of the reaction system is preferably such that the concentration of amorphous aluminosilicate formed by reacting the alkali metal aluminate and the alkali metal silicate is 0.5 to 30% at the end of the reaction, more preferably
1.5 to 25%.

The reaction time (total residence time in at least two or more reactors) is from 1 minute to 120 minutes, but usually from 3 minutes to 60 minutes. When the reaction time is less than 1 minute, the oil absorption capacity is low and the filtration rate is low. On the other hand, if it exceeds 120 minutes, the particles of the product will be large and the oil absorbing ability will be low. Furthermore, even if the residence time in each reactor is equal,
It does not have to be even.

The number of reaction zones (reactor tanks for a multi-stage reactor and raw material injection sites for a tubular reactor) in a continuous reactor is preferably 2 or more and 10 or less, and usually 2 or less.
To 6 are used. In case of 1, sufficient performance (oil absorption capacity, ion exchange capacity) cannot be obtained, and in case of more than 10, equipment becomes complicated and the advantage of continuity is lost. The aging tank receives the reaction solution flowing from the final reaction tank, and
Aged for 120 minutes. Not so strong stirring is required. This aging is preferably performed while the reaction system is kept as it is, but may be performed after partial concentration or concentration by decantation or the like.

The reaction slurry is subjected to solid-liquid separation, for example, filtration to obtain a wet cake. The cake is washed as it is or after being washed with water, and then dried to obtain a fine powder of amorphous aluminosilicate. On the other hand, the filtrate can be recycled as it is or after being neutralized and filtered with an acid, adjusting the salt concentration and the alkali concentration. It is also possible to neutralize the reaction slurry, filter it, and recycle the filtrate. By neutralizing the excess alkali in the reaction product with one or more acid agents selected from inorganic acids, organic acids and acid salts, the separation rate in solid-liquid separation, for example, the filtration rate in the filtration step is very high In addition, performance degradation due to alkali remaining in the product can be easily prevented. Regarding the method of neutralizing the reaction slurry, if a weak acid such as carbonic acid is added directly to the slurry, the performance of the product is not adversely affected. In the case of a strong acid such as hydrochloric acid or sulfuric acid, the solution is neutralized by sufficiently diluting the solution or adding a neutralizing agent to the filtrate separated by a solid-liquid separator as an indirect neutralization method. It is preferable to use a mild neutralization method in which the mixed solution is mixed with a solid obtained by solid-liquid separation.

As described in detail here, a predetermined amount of each of an aqueous solution of an alkali salt, an aqueous solution of an alkali metal aluminate, an aqueous solution of an alkali metal silicate, and, if necessary, alkaline water and water is dropped into the multistage reactor. By doing, the alkali concentration, solids concentration, reaction temperature,
By controlling the residence time and the like, it is possible to continuously produce amorphous aluminosilicate having high oil absorption capacity and high ion exchange capacity.

The amorphous aluminosilicate obtained by the method of the present invention has an unprecedented high oil absorption capacity, a high ion exchange capacity, and a higher refractive index than conventional white carbon for papermaking. It can be said that the inorganic material has more functionality than the white carbon for use. Further, by mixing the surfactant and the amorphous aluminosilicate according to the present invention, a detergent having excellent detergency can be obtained. Furthermore, because of these many functions, it can be used as a filler for paper, especially for lightweight paper, as well as a carrier for gas and fragrance, a detergent, an additive for dentifrice, a sebum control agent, an additive for agricultural chemicals, and an additive for paint. It can be applied to many fields of use such as additives for ceramic binders.

[0028]

According to the method of the present invention, an inexpensive amorphous aluminosilicate having extremely high production efficiency can be produced stably and continuously. At least 15 in terms of performance
It has a high oil absorption capacity of 0 ml / 100 g or more, and 60 mg C
This is a method for producing an amorphous aluminosilicate having a high ion exchange capacity of aCO ₃ / g or more and having a very high filtration rate in a solid-liquid separation step of extracting a product from a reaction slurry.

[0029]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. The percentages in the composition and concentration are all by weight. In the following examples, a multistage reactor type reactor having three to six reactors 3 each having four baffles 2, a turbine type stirrer 1, and a mantle 4 as shown in FIG. Were used as reaction tanks A to F, and a reaction apparatus composed of one aging tank (capacity: 500 cc) and a aging tank (capacity: 500 cc) was used. The stirring speed of the turbine type stirrer 1 is a peripheral speed in the reaction tank.
It was set to 2.6 m / sec. Or more, and adjusted to 1 m / sec. In the aging tank.

As a method for preparing the raw materials used in the following examples, an aqueous alkali metal aluminate solution was added to Al (OH) ₃
% NaOH aqueous solution was added, and the mixture was heated to 120 ° C. and dissolved. The molar ratio of Na ₂ O / Al ₂ O ₃ is 1.15 and Al ₂ O ₃
The content was 29%. As the aqueous solution of the alkali metal silicate, commercially available No. 3 water glass was used. The SiO ₂ / Na ₂ O molar ratio is
3.15 and the SiO ₂ pure content was 29.3%. This was diluted three times with water and used. To adjust the salt concentration of the reaction system as an aqueous solution of an alkali salt, water, a 5% aqueous solution of sodium sulfate, and a mother liquor of the reaction system (containing 6.1% sodium carbonate and a small amount of SiO ₂ )
In addition, a 10% NaOH aqueous solution was used as an alkali concentration adjusting liquid.

Separate laboratory neutralization (if necessary), filtration, and, optionally, washing (as much as twice the volume of the filter cake) for sampling and analysis of the product from the continuous effluent for analysis. Reslurry with water and filter) and cake these 1
The sample dried at 05 ° C, 350 torr and 10 hours was measured by the method described later. The salt concentration in Tables 1 to 3 indicates the salt added to the reaction system and the salt concentration in the product produced by neutralization after the reaction. The composition of the product system indicates the composition in the dried product.

Examples 1 to 4 An aqueous solution of an alkali metal aluminate, an aqueous solution of an alkali metal silicate and an aqueous solution of an alkali salt were prepared at the concentrations shown in Table 1.
Each of them is continuously fed into the multi-stage reactor at a distribution ratio from each stage, and the first-stage reaction liquid overflows to the second stage, and the second-stage raw material is simultaneously sent to the second-stage reactor. Then, at the time when the system overflowed from the aging tank and the system was stabilized, a sample was collected, the composition was analyzed, and the oil absorption capacity, ignition loss, Ca ion exchange capacity, and filtration rate were measured by the following methods.
Table 1 shows these conditions and results. The aging temperature is
At 60 ° C., the residence time was 30 minutes.

(1) Oil Absorption A sample was ground in a mortar and measured by the oil absorption measurement method of JIS K 6220. (2) Ignition loss Pre-baked at 800 ° C for 1 hour, put a few grams of the sample into a magnetic crucible reaching a constant weight in a desiccator, and weigh it accurately. Then, the mixture was ignited in an electric furnace at 800 ° C. for 1 hour, and the weight reached constant weight was precisely weighed in a desiccator to determine the ignition loss in weight%.

(3) Ca ion exchange capacity The sample was precisely weighed in 0.1 g in terms of anhydride calculated from the loss on ignition, added to 100 ml of a calcium chloride solution (500 ppm as CaCO ₃ ), and stirred at 25 ° C. for 15 minutes. No.5C manufactured by Toyo Roshi Co., Ltd.
Two layers were subjected to suction filtration, 50 ml of the filtrate was taken, Ca in the filtrate was titrated by EDTA, and the Ca exchange ability of the sample was determined from the value (unit: CaCO ₃ mg / g). Incidentally, the Ca ion exchange capacity is evaluated to be rather high when the washing of the powder is insufficient. In other words, if excess alkali ions remain, C in the air
It reacts with O ₂ gas to form carbonate, which appears to have high Ca ion exchange capacity. Therefore, the measurement sample must be sufficiently washed.

(4) Filtration Speed Using a nutsche and a suction bottle, the sample was filtered under reduced pressure under the following conditions to obtain a filtration speed.・ Filtration temperature 25 ℃ ~ 27 ℃ ・ Filtration pressure 350torr ・ Filter material (filter paper) No.5C made by Toyo Roshi Co., Ltd. ・ Sample weight Amount to make cake thickness 15-17mm Adjust the pressure of filter to 350torr and adjust this nutche Put the sample in and filter. The filtration time is determined from the filtration area (m ² ) and the sample weight (kg) as the filtration time (Hr) from the point when the sample is introduced to the point at which the slurry or liquid disappears on the nutsche and the gas enters the filtrate (unit: kg) / M ² · Hr).

[0036]

[Table 1]

Examples 5 to 6 Each of an aqueous solution of an alkali metal aluminate, an aqueous solution of an alkali metal silicate, an aqueous solution of an alkali salt, a 10% aqueous solution of NaOH, and ion-exchanged water was continuously prepared at the concentrations and distribution ratios shown in Table 2. The multistage reactor is fed from each stage, the first stage reaction solution overflows to the second stage, and the second stage raw material is fed at the same time. When the system was stabilized, a sample was collected, the composition was analyzed, and the oil absorption capacity, ignition loss, Ca ion exchange capacity, and filtration rate were measured in the same manner as in Examples 1 to 4. Table 2 shows these conditions and results. The aging temperature was 60 ° C. and the residence time was 30 minutes.

Example 7 In this example, a preliminary reaction was performed. That is, 4
In a 5 liter reactor equipped with baffles, a turbine-type stirrer, and a jacket, 191 g of an alkali metal aluminate solution was mixed with 3926 g of an alkali salt aqueous solution, and 350 g of the mixture was added thereto.
Was uniformly dropped in 3 minutes to prepare a preliminary reaction product (reaction temperature: 40 ° C., stirring speed of a stirrer was adjusted to 2.6 m / sec at a peripheral speed). The pre-reacted product was supplied to the first-stage reactor, and 650 g of an aqueous solution of an alkali metal silicate was continuously dropped into the multi-stage reactor at the concentration and distribution ratio described in Table 2, and the first-stage reaction solution was added. At the same time as overflowing to the second stage, the second stage raw material is fed in, and then sequentially fed in this way. When the system overflows from the aging tank and the system is stabilized, a sample is collected, the composition is analyzed, and the sample is analyzed. Oil absorption ability, loss on ignition, Ca ion exchange ability in the same manner as in Examples 1 to 4,
The filtration rate was measured. Table 2 shows these conditions and results. The aging temperature was 60 ° C. and the residence time was 30 minutes.

[0039]

[Table 2]

Comparative Examples 1 to 4 An aqueous alkali metal aluminate solution, an aqueous alkali metal silicate solution and ion-exchanged water were continuously prepared at the concentrations and distribution ratios shown in Table 3 in each of the multistage reactors (however, Comparative Example 1 was a 1-stage reactor). From the respective stages, the first-stage reaction solution overflows to the second stage, and the second-stage raw materials are simultaneously sent in. The second-stage raw materials are sequentially fed in this manner, and overflow from the aging tank. At the time when the system was stabilized, a sample was collected, the composition was analyzed, and the oil absorption capacity, ignition loss, Ca ion exchange capacity, and filtration rate were measured in the same manner as in Examples 1 to 4. Table 3 shows these conditions and results. The aging temperature was 60 ° C. and the residence time was 30 minutes.

[0041]

[Table 3]

As is clear from Table 3, Comparative Example 1 is a single-stage reactor, and thus has poor oil absorption and ion exchange capacity, and has a low filtration rate because no alkali metal salt and / or alkaline earth metal salt is present. Comparative Examples 2 and 3 are three-stage reactors, and thus have good oil absorbing ability and ion exchange ability, but have a low filtration rate due to the absence of alkali metal salts and / or alkaline earth metal salts. Comparative Example 4 has a high concentration reaction and thus has poor oil absorption ability, and has a low filtration rate because no alkali metal salt and / or alkaline earth metal salt is present.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing an example of a multi-stage reactor type reactor used in the production method of the present invention.

FIG. 2 is a schematic cross-sectional view showing one example of a tubular reactor used in the production method of the present invention.

FIGS. 3A and 3B are diagrams showing another example of the tubular reactor used in the production method of the present invention, wherein FIG. 3A is a schematic sectional view and FIG. 3B is a schematic plan view.

[Explanation of symbols]

 1 stirrer 2 baffle plate 3 reactor 4 mantle

Continuation of front page (56) References JP-A-57-61613 (JP, A) JP-A-55-167121 (JP, A) JP-A-55-140713 (JP, A) (58) Fields investigated (Int) .Cl. ⁷ , DB name) C01B 33/00-39/54

Claims (3)

(57) [Claims] 1. An alkali metal aluminate and an alkali metal silicate are mixed with an alkali metal salt (however,
(Excluding metal salts and alkali metal silicates) and / or alkaline earth metal salts at a temperature of from 10 DEG to 100 DEG C., wherein the solution to be reacted has a molar ratio of from 0.5 to 8 M _x O: Al ₂ O ₃ : 1 to 7 SiO ₂ : 50 to 1500 H ₂ O (where M represents an alkali metal, an alkaline earth metal or a mixture thereof, and x is 1 or 2) Is a method for continuously producing an amorphous aluminosilicate by performing an alkali metal salt (however , a multistage reaction tank type reactor or a tubular type reactor).
Alkali metal aluminate and alkali metal silicate
And / or alkaline earth metal salts, alkali metal aluminates, and alkali metal silicates, and at least one of them is continuously injected into a plurality of points in the reactor. Amorphous aluminosilicate is continuously deposited by injecting and reacting to form an amorphous aluminosilicate. 2. The method for continuously producing an amorphous aluminosilicate according to claim 1, wherein the alkali metal salt and / or the alkaline earth metal salt is present in an amount of 0.05 to 25% by weight based on the reaction system. 3. An excess acid in the reaction product is converted into an inorganic acid,
The method for continuously producing an amorphous aluminosilicate according to claim 1 or 2, wherein the method is neutralized with at least one selected from an organic acid and an acid salt.