JP2013166142A - Adsorbent of aromatic chlorine compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adsorbent of an aromatic chlorine compound, which can effectively suppress the occurrence of dioxins.SOLUTION: An adsorbent of an aromatic chlorine compound is made of hydrous magnesium salt having the Mg/Si molar ratio within a range of 0.50 to 1.50.

Description

  The present invention relates to an aromatic chlorine compound adsorbent used for treating combustion exhaust gas generated from a waste incinerator or the like.

  In recent years, environmental pollution due to dioxins contained in combustion exhaust gas generated from waste incinerators such as municipal waste and industrial waste has become a problem. Dioxins are a general term for polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and coplanar polychlorinated biphenyls. They are molecules with high crystallinity. Chloride, oxygen atoms, and benzene, naphthalene, It is known that it is produced from carbon by radical reaction. Therefore, at present, by setting the temperature of the waste incinerator to a high temperature of 800 ° C. or higher, carbon radicals are converted into carbon dioxide as much as possible, and the oxygen concentration in the incinerator is maintained at about 10%. The production of dioxins is suppressed by shortening the residence time of the exhaust gas in the vicinity of 300 ° C., which is a temperature range in which dioxins are easily produced.

  However, even if the incineration temperature is set to a high temperature of 800 ° C. or higher, dioxins are prevented from being re-synthesized somewhere in the cooling process from the high-temperature furnace to the exhaust through the chimney to the atmosphere. Therefore, there is a need for a treatment method that reliably removes dioxin precursors from combustion exhaust gas.

  As a method for treating combustion exhaust gas, for example, Patent Document 1 proposes a method for treating combustion exhaust gas with a filter cloth (bag filter) carrying activated carbon, activated clay, acid clay, or the like. That is, dioxins are removed from combustion exhaust gas by adsorbing dioxins with activated carbon or activated clay.

Patent Document 2 discloses an acidity with a specific surface area of 100 to 800 m ² / g for the purpose of easily preventing the discharge of dioxins from municipal waste incineration facilities and the elution of heavy metals from the generated fly ash with one chemical. White clay, activated clay, bentonite, etc. are used.

  Patent Document 3 proposes an adsorbent for removing harmful substances in exhaust gas, which is made of montmorillonite or a clay mineral containing this as a main component.

  Patent Document 4 discloses that dioxins are adsorbed by adsorbing a surface of acid clay, activated clay, bentonite, etc., which has been hydrophobized with a silane coupling agent, based on the idea that dioxins are very hydrophobic substances. Is removed from the combustion exhaust gas.

Patent Document 5 proposes a dioxin adsorbent comprising a montmorillonite group clay mineral or an acid-treated product thereof and having a Lewis acid content as a solid acid in the range of 0.08 mmol / g or more.
Patent Document 6 includes a smectite clay or an acid-treated product thereof, which contains SiO ₂ , Al ₂ O ₃ and MgO as basic components at a certain ratio, and a total amount of alkali metal and alkaline earth metal of 0.30 to 2. A 10% by weight aromatic chlorine compound generation inhibitor has been proposed.

JP-A-4-87624 Japanese Patent Laid-Open No. 11-9963 JP 2000-325737 A JP-A-10-151343 JP 2006-263587 A JP 2011-218318 A

  However, the activated carbon proposed in Patent Document 1 is excellent in dioxins adsorption ability and also has good hydrocarbon adsorption ability, but activated carbon is a carbon powder and has a problem of combustion. That is, when activated carbon is used for the treatment of combustion exhaust gas held at a high temperature, it itself burns and becomes a source of carbon radicals and thus a source of dioxins. Currently, there is a demand for agents.

  Furthermore, the activated clay as shown in Patent Documents 2 to 4 is obtained by acid-treating acid clay containing montmorillonite as a main component, and has a large specific surface area and pore volume compared to acid clay. However, dioxins adsorption effect is considerably lower than activated carbon and is not suitable as a substitute for activated carbon. Normally, it is not used alone, and it can be used in combination with activated carbon to treat combustion exhaust gas. used.

On the other hand, the dioxin adsorbent or the aromatic chlorine compound generation inhibitor proposed in Patent Documents 5 and 6 is proposed by the present applicant, and effectively uses the hydrocarbon that is the source of dioxins. Compared to the dioxin adsorbents disclosed in the above patent documents, the generation of dioxins can be effectively suppressed.
However, the effects of the dioxin adsorbents and aromatic chlorine compound generation inhibitors proposed in Patent Documents 5 and 6 are not sufficient, and there is a need for an agent that can effectively suppress the generation of dioxins. .

Accordingly, an object of the present invention is to provide an aromatic chlorine compound adsorbent capable of effectively suppressing the generation of dioxins.
Another object of the present invention is to provide a method for treating combustion exhaust gas using the above aromatic chlorine compound adsorbent.

  The present inventors have conducted many experiments on aromatic chlorine compound adsorbents, and as a result of examining the performance thereof, the hydrous magnesium silicate salt having a Mg / Si molar ratio in the range of 0.50 to 1.50 is chlorobenzene. The present inventors have found the knowledge that generation of aromatic chlorine compounds such as these can be more effectively suppressed, and have completed the present invention.

  That is, according to the present invention, there is provided an aromatic chlorine compound adsorbent comprising a hydrous magnesium silicate salt having a Mg / Si molar ratio in the range of 0.50 to 1.50.

In the aromatic chlorine compound adsorbent of the present invention,
(1) The hydrous magnesium silicate salt has a specific surface area of 345 to 800 m ² / g,
In particular,
(2) The hydrous magnesium silicate salt is composed of layered hydrous magnesium silicate and has a methylene blue adsorption capacity in the range of 45 to 80 mmol / 100 g.
Or
(3) The hydrous magnesium silicate salt is composed of amorphous hydrous magnesium silicate and has a methylene blue adsorption capacity in the range of 45 to 80 mmol / 100 g.
Or
(4) The hydrous magnesium silicate salt comprises a stevensite,
(5) The stevensite is preferably composed of a synthetic stevensite-type magnesium sodium phyllosilicate composed of magnesium, sodium and silicon only, and has a methylene blue adsorption capacity in the range of 75 to 120 mmol / 100 g.
Or
(6) The hydrous magnesium silicate salt is composed of a chain clay mineral having a CaO content of 1.5% by mass or less,
Is preferred.

  According to the present invention, there is further provided a combustion exhaust gas treatment method characterized in that combustion exhaust gas generated from waste incineration is treated using the aromatic chlorine compound adsorbent.

In the present invention, the hydrous magnesium silicate salt having a Mg / Si molar ratio in the range of 0.50 to 1.50 effectively adsorbs the aromatic chlorine compound generated as an intermediate during the dioxin production process. By treating the combustion exhaust gas generated from incineration, aromatic chlorine compounds in the exhaust gas can be adsorbed and captured, and the generation of dioxins can be effectively suppressed through adsorption of such aromatic chlorine compounds. .
That is, dioxins are aromatic chlorines such as chlorobenzenes, chlorophenols, chloronaphthalenes and the like when carbon radicals react with chloride-derived chlorine atoms and air-derived oxygen atoms in an incinerator, for example. A compound is produced, and this aromatic chlorine compound is produced by further coupling reaction. As shown in the examples described later, the aromatic chlorine compound adsorbent of the present invention has a characteristic of effectively adsorbing an aromatic chlorine compound (for example, chlorobenzene) generated as an intermediate in the process of generating dioxins. As a result, the generation of dioxins can be effectively suppressed.
Moreover, such a hydrous magnesium silicate salt is excellent not only in the ability to capture heavy metals such as Pb, but also excellent in suppressing elution in an aqueous system after capture.

  The fact that a hydrous magnesium silicate salt having a Mg / Si molar ratio in the range of 0.50 to 1.50 used in the present invention can adsorb aromatic chlorine compounds suitably has been found as a phenomenon. The exact reason has not been elucidated. However, the present inventors believe that the hydrous magnesium silicate salt having a Mg / Si molar ratio in the above range has an affinity and a layer structure suitable for adsorption of aromatic chlorine compounds such as chlorobenzene. thinking.

A molecular model diagram schematically showing a trioctahedral three-layer structure.

<Water-containing magnesium silicate salt>
The aromatic chlorine compound adsorbent of the present invention comprises a hydrous magnesium silicate salt having a Mg / Si molar ratio in the range of 0.50 to 1.50. In the present invention, any hydrated magnesium silicate salt having a Mg / Si molar ratio in the above range can be used. Among them, those having a trioctahedral type three-layer structure can be preferably used. As shown in the model diagram of FIG. 1, the trioctahedral three-layer structure, which is the basic structure, has a three-layer structure in which two SiO ₄ tetrahedra are sandwiched with an MgO ₆ octahedral layer sandwiched therebetween. Have. It is considered that the formation of such a three-layer structure greatly improves the adsorptivity of aromatic chlorine compounds.

  The hydrous magnesium silicate having the above trioctahedral type three-layer structure is not particularly limited as long as it has this structure, but is preferably classified into layered or amorphous hydrous magnesium silicate and stevensite. Is done.

The hydrous magnesium silicate having the trioctahedral type three-layer structure described above also has a specific surface area according to the BET method in the range of 345 to 800 m ² / g in that the adsorption ability to the aromatic chlorine compound is sufficiently exhibited. Preferably, it is in the range of 385 to 800 m ² / g.

1． Layered or amorphous hydrous magnesium silicate;
Layered or amorphous hydrous magnesium silicate is based on a three-layer structure in which two SiO ₄ tetrahedral layers are sandwiched with an MgO ₆ octahedral layer sandwiched therebetween. If this basic structure is laminated in the c-axis direction, it is layered, and if the number of laminations is extremely small or the degree of lamination is incomplete, it is amorphous.

The layered or amorphous hydrous magnesium silicate has pores in the hexacoordinate Mg portion of the trioctahedral three-layer structure shown in the model of FIG. Ideally, the following formula (1);
(M ⁺ , M _1/2 ²⁺ ) _2X (Mg _{3 -X} □ _X ) Si ₄ O ₁₀ (OH) ₂ .nH ₂ O
(1)
In the formula, □ represents a hole formed in hexacoordinate Mg,
M represents an exchangeable cation,
X is a number from 0 to 1/3,
n is a number of 5 or less,
For example, it is disclosed in Japanese Patent Publication No. 3-51651 or Japanese Patent Publication No. 7-24765.

  The layered hydrous magnesium silicate exhibits diffraction peaks at interplanar spacings of 4.5 to 4.6 mm, 2.5 to 2.6 mm, and 1.5 to 1.6 mm, for example, by powder method X-ray diffraction measurement. Are the same X-ray diffraction peaks common to natural trioctahedral layered clay minerals.

  The layered or amorphous hydrous magnesium silicate preferably has a methylene blue adsorption capacity (MB adsorption capacity) in the range of 45 to 80 mmol / 100 g.

2. The stevensite is generally represented by the following formula (Mg _2.88 Mn _0.02 Fe _0.02 ) Si ₄ O ₁₀ (OH) ₂
(Ca, Mg) _0.07 (2)
This mineral is a clay mineral having a chemical composition represented by the following formula. A part of the magnesium component of the trioctahedral three-layer structure [Mg ₃ Si ₄ O ₁₀ (OH) ₂ ] is substituted with another metal. The other part of the compound is vacant. In the present invention, it is preferable to use a metal component composed of a synthetic stevensite magnesium sodium phyllosilicate composed solely of magnesium, sodium and silicon. Although it is possible to use a natural product by a treatment such as removing impurities, it is preferable to use a synthetic product, particularly a synthetic stevensite whose metal components are composed only of magnesium, sodium and silicon.

A suitable stevensite has a structure in which Na enters the interlayer between the trioctahedral type three-layer structure or the vacancies, and the following formula (3);
(Mg _x Na _y ) Si ₄ O ₁₀ (OH) ₂ .Na _z (3)
Where x and y are under the condition x + y <3,
x is a number of 2 or more,
y is a number from 0 to 0.1;
z is a number greater than 0 and up to 1.0;
It has the chemical composition represented by these. Such a steven site is disclosed in, for example, Japanese Patent Laid-Open No. 63-190705.

  That is, stevensite also exhibits the aforementioned X-ray diffraction peak characteristic of the trioctahedral three-layer structure, and such a structure exhibits excellent adsorption characteristics for aromatic chlorine compounds such as chlorobenzene.

  The stevensite also shows an X-ray diffraction image peculiar to the smectite clay mineral, and has, for example, an X-ray diffraction peak at an interplanar spacing of 16 to 26 mm in the state of being treated with ethylene glycol.

  Further, the stevensite has an MB adsorption capacity in the range of 75 to 120 mmol / 100 g, which is a factor of high adsorptivity to aromatic chlorine compounds such as chlorobenzene. In the above formula (3), z represents the sum of the number of exchangeable Na atoms existing between the layers and the number of Na atoms adhering to each other. The adhering Na increases the amount of adsorbed MB, but in the present invention, it is preferable to reduce it as much as possible in order to improve the adsorption performance for aromatic chlorine compounds. Adhering Na can be separated by a semipermeable membrane or the like.

3. Chain Clay Mineral Use of a chain clay mineral having a CaO content of 1.5% by mass or less as the hydrous magnesium silicate used in the present invention is effective as an aromatic chlorine compound adsorbent. In the chain clay mineral having a CaO content exceeding 1.5% by mass, the adsorption of the aromatic chlorine compound is insufficient as shown in a comparative example described later. Examples of chain clay minerals include sepiolite, attapulgite, and palygorskite.

4). Production of hydrous magnesium silicate salt;
When producing layered or amorphous hydrous magnesium silicate, magnesia or its hydrate (A) and silica (B) are preferably used in the reaction in stoichiometric amounts. The molar ratio of MgO: SiO ₂ can be varied in the range of 2: 4 to 6: 4, and is most preferably 3: 4. A layered hydrous magnesium silicate can be obtained by hydrothermal treatment of both reactions at a temperature of 110 to 200 ° C. using an autoclave. On the other hand, when it is carried out at a relatively low temperature of 70 to 85 ° C., amorphous hydrous magnesium silicate is obtained. The reaction time depends on the raw materials and the like, but is carried out for about 0.5 to 25 hours within the above temperature range.

  When producing stevensite, caustic soda may be added and used as a Na source during the hydrothermal treatment. The amount of Na may be used in an amount that satisfies the above-described formula (3). In particular, as described in JP-A-63-190705, by subjecting an aqueous mixture containing basic magnesium carbonate and sodium silicate (or amorphous silica and sodium hydroxide) to hydrothermal treatment. It is preferable to manufacture.

  In order to obtain a chain clay mineral having a CaO content of 1.5% by mass or less, a natural chain clay mineral is purified so that the CaO content is 1.5% by mass or less. As for, there is no particular limitation as long as the adsorption performance of the aromatic chlorine compound is not impaired.

  The hydrous magnesium silicate salt having a Mg / Si molar ratio in the range of 0.50 to 1.50 obtained as described above is appropriately dehydrated or dried to form granules, powders, cakes or nodules. If necessary, the product is pulverized, classified, or molded to obtain a desired particle shape and used for dioxin generation suppression (that is, an aromatic chlorine compound adsorbent).

<Aromatic chlorine compound adsorbent>
The above-mentioned hydrous magnesium silicate salt having a Mg / Si molar ratio in the range of 0.50 to 1.50 can be used alone as an aromatic chlorine compound adsorbent, for example, for the treatment of combustion exhaust gas. It can also be used in combination with a known dioxin adsorbent or hydrocarbon adsorbent. For example, the silica-magnesia composite oxide described in JP-A-2005-8676 is extremely effective as a dioxin adsorbent. Therefore, combustion using such a silica-magnesia composite oxide in combination with the aromatic chlorine compound adsorbent of the present invention (hydrous magnesium silicate having a Mg / Si molar ratio in the range of 0.50 to 1.50) It can be used for exhaust gas treatment.

  For example, combustion exhaust gas generated from a garbage incinerator is collected from a chimney after being collected by a bag filter made of a filter cloth, etc., but before passing through the bag filter, the aromatic chlorine compound adsorbent of the present invention is used. It is good to process. As a result, the aromatic chlorine compound serving as an intermediate for generation of dioxins can be effectively adsorbed and removed, so that generation of dioxins in the exhaust gas can be effectively suppressed.

The treatment with the aromatic chlorine compound adsorbent as described above is usually carried out by blowing it into the flue, and a bag filter is provided in the flue, and the aromatic chlorine compound adsorbent (and the above-described one) It is also possible to carry a dioxin adsorbent such as silica / magnesia composite oxide.
In addition, what is necessary is just to set suitably the blowing amount of a dioxin generation | occurrence | production inhibitor, the carrying amount, etc. according to the performance (the amount of exhaust gas, the generation amount of dioxins or hydrocarbons) of an incinerator.

  In the treatment of the combustion exhaust gas of the present invention using the aromatic chlorine compound adsorbent described above, in combination with the treatment using the aromatic chlorine compound adsorbent, other treatment known per se, such as slaked lime, etc. By blowing alkaline powder and absorbing acidic gas such as HCl, or passing through a platinum catalyst layer, CO or hydrocarbon can be burned or pyrolyzed to reduce harmful gases.

  The invention is further illustrated in the following examples. In addition, the test method performed in the Example is as follows.

(1) X-ray diffraction Using a sample powder type X-ray diffractometer Ultima IV (manufactured by Rigaku), an X-ray diffraction pattern was measured under the following conditions.
Target Cu
Filter Ni
Detector SC
Voltage 40KV
Current 40mA
Scanning speed 3 ° / min
Sampling width 0.02 °
Slit: DS 0.5 °, RS 0.3mm, SS 0.5 °

得られた分析データより、ＳｉＯ_２、Ａｌ_２Ｏ_３、ＭｇＯ、Ｎａ_２Ｏ、Ｋ_２Ｏ、ＣａＯ、Ｆｅ_２Ｏ_３、ＴｉＯ_２、ＳＯ_３の合計が１００重量％になるように補正し、化学組成値を算出した。 (2) using a chemical composition (Ltd.) manufactured by Rigaku Rigaku RIX2100, target Rh, analysis line in K _alpha, others were measured under the following conditions.

From the obtained analysis data, it is corrected so that the total of SiO ₂ , Al ₂ O ₃ , MgO, Na ₂ O, K ₂ O, CaO, Fe ₂ O ₃ , TiO ₂ , SO ₃ becomes 100% by weight, Chemical composition values were calculated.

(3) Specific surface area Using Tri Star 3000 manufactured by Micromeritics, analysis was performed by BET method from an adsorption branch side nitrogen adsorption isotherm having a specific pressure of 0.05 to 0.25.

(4) Methylene blue adsorption capacity (MB adsorption capacity)
Based on Japan Bentonite Industry Association Standard Test Method JBAS-107-77, 0.5N sulfuric acid was added without measurement, and then the moisture was corrected to calculate MB adsorption capacity (mmol / 100 g).

(5) Adsorption test (chlorobenzene adsorption performance)
After 0.5 g of a sample heat-treated at 200 ° C. for 30 minutes was collected in a 1.8 L glass bottle and sealed, chlorobenzene prepared by vaporization in advance was injected to 50 to 100 ppm. One hour after gas injection, the gas concentration was measured with a gas detector tube, and the gas injection operation was repeated until the gas concentration reached 5 ppm or more. Thereafter, the amount of gas adsorbed until the gas concentration reached 5 ppm was determined, and the gas adsorption amount (5 ppm equilibrium) (mg / g) of the sample was determined.

(6) Heavy metal elution test Using a bag filter fly ash (Pb 2400 ppm, Zn 6100 ppm) of an incinerator, an elution test for Pb and Zn was performed in accordance with Ministry of the Environment Notification No. 13. The amount of sample added was 5 parts by weight with respect to fly ash. The dissolution test solution had a pH of about 12.0 / 25 ° C.

Example 1
The silica filter cake synthesized by the precipitation method was added to water to prepare a 10 mass% silica suspension. Magnesium hydroxide (# 200) manufactured by Kamishima Chemical was added to water to prepare a 10 mass% Mg (OH) ₂ suspension. Next, the Mg (OH) ₂ suspension is poured into a normal temperature silica suspension so that the Mg / Si molar ratios described in Table 1 are mixed, and the mixture is mixed and reacted at 130 ° C. for 5 hours. did. After the reaction, it was washed with filtered water and dried to obtain a powder sample. The powder sample was confirmed to be a layered hydrous magnesium silicate having a peak similar to that of the trioctahedral layered clay mineral by X-ray diffraction measurement. The results of measuring the physical properties of the obtained powder samples are shown in Tables 1 and 2.

(Example 2)
A layered hydrous magnesium silicate powder sample was obtained in the same manner as in Example 1 except that the Mg / Si molar ratio was 0.50 and the reaction temperature was changed to 170 ° C. The results of measuring the physical properties of the obtained powder samples are shown in Tables 1 and 2.

(Examples 3 to 5)
A layered hydrous magnesium silicate powder sample was obtained in the same manner as in Example 2 except that the Mg / Si molar ratio described in Table 1 was used. Tables 1 and 2 show the physical property measurement results of the obtained powder samples.

(Comparative Example 1)
We used acid clay from Tsuruoka City, Yamagata Prefecture. The results of measuring the physical properties of the powder samples are shown in Tables 3 and 4.

(Examples 6-12, Comparative Examples 2-3)
The silica filter cake synthesized by the precipitation method was added to water to prepare a 10 mass% silica suspension. Magnesium hydroxide (# 200) manufactured by Kamishima Chemical was added to water to prepare a 10 mass% Mg (OH) ₂ suspension. Next, an Mg (OH) ₂ suspension was poured into a normal temperature silica suspension so as to have the Mg / Si molar ratios described in Table 3 and mixed, and reacted at 80 ° C. for 20 hours. After the reaction, it was washed with filtered water and dried to obtain a powder sample. The powder sample was confirmed to be amorphous hydrous magnesium silicate by X-ray diffraction measurement. Tables 3 and 4 show the physical property measurement results of the obtained powder samples.

(Example 13)
A powder sample of amorphous hydrous magnesium silicate was obtained in the same manner as in Example 8, except that the Mg raw material was changed to Mg oxide and the reaction was changed to 80 ° C. for 10 hours. Table 3 shows the results of the physical property measurement of the obtained powder sample.

(Example 14)
A synthetic steven site, Ionite made by Mizusawa Chemical, was used. The results of measuring the physical properties of the powder samples are shown in Tables 5 and 6.

(Example 15)
A synthetic stevensite (Ionite manufactured by Mizusawa Chemical) different from Example 14 was used. The results of measuring the physical properties of the powder sample are shown in Table 5.

(Experimental example 1)
A natural steven site, Trusa ATOX, was used. The results of measuring the physical properties of the powder sample are shown in Table 5.

(Example 16)
Sepiolite (Mizusawa Chemical Ade Plus) having a CaO content of 0.89% by mass was used. The results of measuring the physical properties of the powder samples are shown in Tables 7 and 8.

(Example 17)
Sepiolite (Mizusawa Chemical Aid Plus) having a CaO content of 0.84% by mass was used. The results of measuring the physical properties of the powder samples are shown in Tables 7 and 8.

(Comparative Example 4)
Palygorskite with a CaO content of 3.31% by mass (SMECTA made by Torusa)
GEL) was used. The results of measuring the physical properties of the powder sample are shown in Table 7.

(Example 18)
A silica-magnesia composite oxide having an Mg / Si molar ratio of 0.89 was used. The production method was synthesized according to the description in JP-A-2005-8676. When the chlorobenzene adsorption performance was measured, it was 7.2 mg / g. Further, when the amorphous hydrous magnesium silicate of Example 8 and the silica-magnesia composite oxide were mixed at a weight ratio of 50:50, the chlorobenzene adsorption performance was measured and found to be 8.8 mg / g. .

Claims (8)

  An aromatic chlorine compound adsorbent comprising a hydrous magnesium silicate salt having a Mg / Si molar ratio in the range of 0.50 to 1.50. ^2. The aromatic chlorine compound adsorbent according to claim 1, wherein the hydrous magnesium silicate salt has a specific surface area of 345 to 800 m ² / g.   3. The aromatic chlorine compound adsorbent according to claim 1, wherein the hydrous magnesium silicate salt is composed of layered hydrous magnesium silicate and has a methylene blue adsorption capacity in the range of 45 to 80 mmol / 100 g.   3. The aromatic chlorine compound adsorption according to claim 1, wherein the hydrous magnesium silicate is composed of amorphous hydrous magnesium silicate and has a methylene blue adsorption capacity in the range of 45 to 80 mmol / 100 g. Agent.   The aromatic chlorine compound adsorbent according to claim 1 or 2, wherein the hydrous magnesium silicate salt comprises stevensite.   6. The stevensite is composed of a synthetic stevensite-type magnesium sodium phyllosilicate consisting of magnesium, sodium and silicon only, and has a methylene blue adsorption capacity in the range of 75 to 120 mmol / 100 g. Aromatic chlorine compound adsorbent.   The aromatic chlorine compound adsorbent according to claim 1, wherein the hydrous magnesium silicate is composed of a chain clay mineral having a CaO content of 1.5% by mass or less.   A combustion exhaust gas treatment method characterized by treating the combustion exhaust gas generated from waste incineration using the aromatic chlorine compound adsorbent according to any one of claims 1 to 7.

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