JP2004002132A - Zeolite powder granule and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a zeolite powder granule excellent in an ion exchanging ability and preferably used for a water cleaning agent and its manufacturing method to manufacture inexpensively the high purity zeolite powder granule without pressure a treatment using an autoclave or the like and without a binder. <P>SOLUTION: The zeolite powder granule has the Al/Si ratio of 0.3-1.5 and has a crystal structure at least denoted as M<SB>2</SB>Al<SB>2</SB>Si<SB>2</SB>.<SB>08</SB>O<SB>8</SB>.<SB>16</SB>_3H<SB>2</SB>O (wherein, M is an alkali metal). Its maximum diameter is set to be 0.5-15 mm. <P>COPYRIGHT: (C)2004,JPO

Description

【００４４】
実施例１〜７、比較例１〜７で得られた粉粒体の陽イオン交換性能、結晶構造、モルフォロジーを以下の方法で測定した。
陽イオン交換性能：得られた粒状物を、蒸留水によりｐＨが８．５以下になるまで水洗し、そのうち２．５ｇの粒状物をＰｂ濃度５００ｐｐｍのＰｂＣｌ２水溶液に浸漬し、３０分後のＰｂ濃度をＩＰＣにより定量化した。
結晶構造：乳鉢により微粉砕し粉末Ｘ線解析法によりＸ線解析装置（理学社製、ＲＩＮ１１００）によりＣｕＫα線により走査速度１゜／分で測定した。得られた解析ピークをＪＣＰＤＳとフィッティングし、結晶構造を同定した。
【００４５】
以上の結果を表２、３に纏めて示した。
【００４６】
【表２】

【００４７】
【表３】

【００４８】
【発明の効果】
本発明のゼオライト粉粒体は、上述の如きものであるから、イオン交換能力に優れ、水浄化剤として好適に使用されるものとなる。
【００４９】
本発明のゼオライト粉粒体の製造方法は、上述の如きものであるから、オートクレーブなどの加圧処理なしに高純度でしかもバインダーを用いることなく安価に製造することができる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a zeolite powder and a method for producing the same.
[0002]
[Prior art]
Natural zeolites contain 60 to 80% by weight of zeolite having an Al / Si ratio of 0.2, such as kryptinolite and mordenite, and are used as an inexpensive resource, but the purity of the zeolite component is low. In addition, since it contains more Si than Al, the cation exchange ability is low, and there is a problem that other usable fields are narrow, including those in which such ability is required.
[0003]
On the other hand, according to the hydrothermal synthesis method, by controlling the composition of the starting material and the autoclave conditions, an aluminum-rich synthetic zeolite having an Al / Si ratio of 1 and excellent in cation exchange capacity can be obtained.
[0004]
However, since synthetic zeolites are usually in the form of fine powder with a maximum width of several μm order, for example, when used as a filter medium for water purification, particles having a maximum width of several mm order to improve handling properties. However, there is a problem that the production is troublesome and expensive.
[0005]
On the other hand, JP-A-11-246214 discloses that a synthetic sodium A-type zeolite powder is mixed with a clay binder having a fibrous one-dimensional structure and water so that the bulk density becomes 0.8 to 1.0 kg / liter. A method for producing a zeolite bead body is disclosed in which the mixture is kneaded and kneaded, then shaped into beads by tumbling granulation of a blade stirring type, and then fired, ion-exchanged and activated.
[0006]
However, in this method, since a binder is used, there is a problem that the active ingredient of zeolite is diluted, and the ion exchange capacity does not exceed a certain level.
[0007]
[Problems to be solved by the invention]
The present invention solves the above problems, has excellent ion exchange capacity, zeolite powder and granules preferably used as a water purifying agent, and without using a binder with high purity without pressure treatment such as an autoclave An object of the present invention is to provide a method for producing a zeolite powder that can be produced at low cost.
[0008]
[Means for Solving the Problems]
The zeolite powder of the present invention has an Al / Si ratio of 0.3 to 1.5, and has at least M ₂ Al ₂ Si ₂ . ₀₈ O ₈ . _It has a crystal structure of 16.3H ₂ O (M is an alkali metal) and has a maximum width of 0.5 to 15 mm.
[0009]
In the present invention, zeolite refers to a siliceous exchanger made of an aluminum hydrous tectosilicate mineral containing an alkali metal or an alkaline earth metal.
[0010]
In general, the zeolite ion exchange reaction of the zeolite powder of the present invention is expressed by attracting cations in order to maintain the charge balance by replacing tetravalent Si with trivalent Al. Therefore, it is considered that the higher the Al / Si ratio, the higher the ion exchange capacity of the zeolite.
[0011]
As described above, ordinary natural zeolites have a crystal structure with an Al / Si ratio of 0.2. M ₂ Al ₂ Si ₂ . ₀₈ O ₈ . Zeolite having a _{16 ·} 3H 2 _O structures are those having a high ion exchange capacity, excess Al is not incorporated in the zeolite crystals, the crystallization of the zeolite is reduced, which decreases the ion exchange capacity Because. Therefore, the Al / Si ratio is limited to 0.3 to 1.5, preferably 0.5 to 1.0.
[0012]
The zeolite powder of the present invention can have an arbitrary particle size by appropriately pulverizing and classifying the cured zeolite, but when used for water purification, if the maximum width is less than 0.5 mm, solid-liquid separation is performed. It is necessary to use a fine-grained filter, and the filter is clogged and the filtration speed is reduced. On the other hand, if it is larger than 15 mm, the contact area with the polluted water to be purified is reduced, and the purification capacity is reduced. Therefore, the maximum spread is limited to 0.5 to 15 mm, and preferably 2 to 10 mm.
[0013]
In the method for producing a zeolite according to the present invention, the water glass and the active powder obtained by applying mechanical energy to the aluminum compound may have an Al / Si ratio of 0.3 to 1.5. After mixing and curing, heat treatment is performed at a temperature of 80 ° C. or higher.
[0014]
The water glass is generally called sodium silicate and represented by a general formula M ₂ O · n (SiO ₂ ) · m (H ₂ O) (M is an alkali metal).
[0015]
As the aluminum compounds, such as aluminum hydroxide [Al _{(OH) 3],} kaolinite _{[Al 2 Si 2 O 5 (OH} ) 4 ], halloysite _{[Al 2 Si 2 O 5 (OH} ) 4 · 2H 2 O And clay minerals such as montmorillonite and pyrophyllite. Among them, an aluminum compound having a hydroxyl group, which can easily obtain mechanochemical activity by the action of mechanical energy, is preferable.
[0016]
The active powder used in the present invention according to claim 2 is obtained by applying mechanical energy to the aluminum compound.
[0017]
Examples of the device for applying the mechanical energy include a medium stirring type mill, a planetary mill, a rolling ball mill, a vibration mill, and the like, and a medium stirring type mill or a planetary mill that requires a short processing time are preferable. In particular, an inner-cylinder rotary-type medium-stirring mill that can easily induce a mechanochemical reaction and is particularly preferable. An example of such an inner cylinder rotary type medium stirring type mill is “Ultra Fine Mill” manufactured by Mitsubishi Heavy Industries, Ltd.
[0018]
The mechanical energy applied is preferably 0.3 kWh or more per kg of the aluminum compound. If less than this, it takes a long time to cure. On the other hand, even if a large amount of energy is applied, the reaction time is not shorter than the reaction rate, so that it is useless.Also, there is a possibility that the purity may decrease due to contamination due to abrasion of the apparatus. It is preferably 20 kWh or less per kg of the compound.
By applying mechanical energy to the aluminum compound, the reactivity with water glass is significantly improved.
[0019]
According to the second aspect of the present invention, the water glass and the active powder are mixed so that the Al / Si ratio becomes 0.3 to 1.5, cured, and then heat-treated. By mixing the water glass and the active powder, a polycondensation reaction occurs, and an amorphous aluminum silicate polymer is generated.
[0020]
The heat treatment is performed at 80 ° C. or higher. If the temperature is lower than 80 ° C., M ₂ Al ₂ Si ₂ . ₀₈ O ₈ . _This is because zeolite crystals represented by 16.3H ₂ O are not generated. At a temperature of 100 ° C. or higher, crystallization proceeds in a shorter time. However, since a pressure-resistant container is required and the equipment becomes large-scale, the temperature is preferably 100 ° C. or lower.
The heat treatment is desirably performed in a closed container so that moisture does not escape. The heat treatment time is such that the higher the heat treatment temperature is, the shorter the crystallization time is, but it is usually 1 to 24 hours. A general oven can be used for heating, and a seal with a wrap or the like is generally used to prevent evaporation of water.
[0021]
According to the second aspect of the present invention, the cured zeolite is subjected to heat treatment, and then, if necessary, crushed and classified to obtain a powder having an arbitrary particle size. A general pulverizer and a classifier can be applied to the pulverization and classification as described above.
[0022]
In the method for producing a zeolite of the present invention according to claim 3, water glass and metakaolin are mixed so that the Al / Si ratio becomes 0.3 to 1.5, and after curing, the mixture is heated to 80 ° C or higher. The heat treatment is performed at a temperature.
[0023]
The metakaolin is an amorphous crystal obtained by heating kaolin to 500 to 600 ° C. and dehydrating water of crystallization, and is the same as the active powder used in the present invention according to claim 2. And the reactivity with water glass is remarkably improved as compared with kaolin.
[0024]
(Action)
The zeolite of the present invention has an Al / Si ratio of 0.3 to 1.5 and at least M ₂ Al ₂ Si ₂ . ₀₈ O ₈ . Since a _{16 ·} 3H 2 _O crystal structure, excellent in ion exchange capacity, the maximum distance across is the 0.5 to 15 mm, particularly those preferably used in the water purification.
[0025]
In the method for producing a zeolite according to the present invention, the water glass and the active powder obtained by applying mechanical energy to the aluminum compound may have an Al / Si ratio of 0.3 to 1.5. After being mixed and cured, heat treatment is performed at a temperature of 80 ° C. or higher. By applying mechanical energy to the aluminum compound, the reactivity with water glass is remarkably improved, and the condensation polymerization with water glass is performed. A reaction occurs and the curing reaction proceeds. Thereafter, by performing a heat treatment at a temperature of 80 ° C. or more, crystallization can be easily performed without a pressure treatment such as an autoclave.
[0026]
In the method for producing a zeolite of the present invention according to claim 3, water glass and metakaolin are mixed so that the Al / Si ratio becomes 0.3 to 1.5, and after curing, the mixture is heated to 80 ° C or higher. Since heat treatment is performed at a temperature, a condensation polymerization reaction between metakaolin and water glass occurs, and a curing reaction proceeds. Thereafter, by performing a heat treatment at a temperature of 80 ° C. or more, crystallization can be easily performed without a pressure treatment such as an autoclave.
[0027]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, the present invention will be described in detail based on examples.
[0028]
(Example 1)
As an aluminum compound, 1.5 kg of Al (OH) ₃ (manufactured by Sumitomo Chemical Co., Ltd., product number “C-31”) is mixed with 45 kg of zirconia spheres having a diameter of 10 mm as a pulverizing medium, and an inner cylinder rotary type medium stirring type mill (Mitsubishi Corporation Manufactured under the trade name “Ultra Fine Mill AT-25 Model”), the mechanical energy is applied by 0.5 kWh per 1 kg of Al (OH) ₃ at an outer cylinder rotation speed of 100 rpm and an inner cylinder rotation speed of 100 rpm. Active powder A comprising the compound was obtained.
[0029]
The obtained active powder A, water glass (manufactured by Nippon Chemical Industry Co., Ltd., product number “SCS-1”, solid content concentration: 45 wt%), and potassium hydroxide were mixed at an elemental ratio of Al / Si / K of 1 / A predetermined amount was added so as to be 1/1, and the mixture was stirred. After stirring, the mixture was cast into a plastic container, covered with a film such as polyvinylidene chloride, cured by heat treatment in an oven at 100 ° C. for 24 hours, pulverized by a hammer mill, and passed through a sieve at the maximum. The powder was classified to 18 to 4.75 mm to obtain a zeolite powder.
[0030]
(Example 2)
Example 1 was repeated except that the active powder A was replaced with an active powder B obtained by operating at 80 ° C. for 24 hours so that the mechanical energy was 1 kWh per 1 kg of Al (OH) _3. Similarly, zeolite powder was obtained.
[0031]
(Example 3)
Activated powder obtained by using kaolin (Kaolin from Georgia, manufactured by Sanyo Clay Co., Ltd.) as an aluminum compound in place of active powder A so that the ratio of Al, Si, K is 1/3 / 1.5 A zeolite powder was obtained in the same manner as in Example 1 except that the body C was used.
[0032]
(Example 4)
An zeolite powder was obtained in the same manner as in Example 1 except that an autoclave was used instead of the oven, and the heat treatment was performed at 120 ° C. for 5 hours.
[0033]
(Example 5)
A zeolite powder was obtained in the same manner as in Example 4, except that the heat treatment was performed at 150 ° C. for 5 hours.
[0034]
(Example 6)
A zeolite powder was obtained in the same manner as in Example 1 except that metakaolin (manufactured by Tsuchiya Kaolin Industries, product number “SP-33”) was used instead of the active powder A.
[0035]
(Example 7)
A zeolite powder was obtained in the same manner as in Example 1 except that the heat treatment was performed at 80 ° C. for 24 hours.
[0036]
(Comparative Example 1)
As a zeolite, a natural zeolite (Izumo, Izukalite) was used and pulverized and classified in the same manner as in Example 1 to obtain a zeolite powder.
[0037]
(Comparative Example 2)
As the zeolite, a zeolite having an Al / Si ratio of 1 (manufactured by Wako Pure Chemical Industries, product number “A-3”, average particle size 75 μm, autoclave method) was used.
[0038]
(Comparative Example 3)
A zeolite granule was obtained in the same manner as in Example 1 except that the zeolite was classified into 15 to 30 mm by a sieve at the time of classification.
[0039]
(Comparative Example 4)
Granules were obtained in the same manner as in Example 1 except that mechanical energy was not applied to Al (OH) ₃ in place of the active powder A (referred to as “active powder D” in Table 1). .
[0040]
(Comparative Example 5)
A powder was obtained in the same manner as in Example 1 except that the heat treatment temperature was 60 ° C.
[0041]
(Comparative Example 6)
50% by weight of the zeolite used in Comparative Example 2 and 50% by weight of Portland cement as a binder were mixed and granulated, and a granular material was obtained in the same manner as in Example 1.
[0042]
(Comparative Example 7)
A powder was obtained in the same manner as in Example 1 except that kaolin (Kaolin manufactured by Sanyo Clay Co., Georgia) was used instead of Al (OH) ₃ .
[0043]
The active powders A to D are summarized in Table 1.
[Table 1]

[0044]
The cation exchange performance, crystal structure, and morphology of the granules obtained in Examples 1 to 7 and Comparative Examples 1 to 7 were measured by the following methods.
Cation exchange performance: The obtained granules were washed with distilled water until the pH became 8.5 or less, and 2.5 g of the granules were immersed in an aqueous solution of PbCl2 having a Pb concentration of 500 ppm, and the Pb after 30 minutes. The concentration was quantified by IPC.
Crystal structure: It was pulverized with a mortar and measured by a powder X-ray analysis method using an X-ray analyzer (RIN1100, manufactured by Rigaku Corp.) with CuKα radiation at a scanning rate of 1 ° / min. The obtained analytical peak was fitted with JCPDS to identify the crystal structure.
[0045]
The above results are summarized in Tables 2 and 3.
[0046]
[Table 2]

[0047]
[Table 3]

[0048]
【The invention's effect】
Since the zeolite powder of the present invention is as described above, it has excellent ion exchange capacity and is suitably used as a water purifying agent.
[0049]
Since the method for producing zeolite powder of the present invention is as described above, it can be produced at high purity without using a pressure treatment such as an autoclave and at low cost without using a binder.

Claims (3)

An Al / Si ratio of 0.3 to 1.5,
At least M ₂ Al ₂ Si ₂ . ₀₈ O ₈ . ₁₆ · _3H 2 O (M represents an alkali metal) has a crystal structure,
A zeolite powder having a maximum width of 0.5 to 15 mm. Water glass and an active powder obtained by applying mechanical energy to an aluminum compound are mixed so that the Al / Si ratio becomes 0.3 to 1.5, and after being cured, at a temperature of 80 ° C. or more. The method for producing a zeolite powder according to claim 1, wherein heat treatment is performed. The water glass and metakaolin are mixed and cured so that the Al / Si ratio becomes 0.3 to 1.5, and then heat-treated at a temperature of 80C or higher. Production method of zeolite powder.