JPS6297641A - Adsorbing material for carcinogen - Google Patents

Abstract

PURPOSE:To enhance the adsorbing capacity of a carcinogen, by forming an adsorbing material from a synthetic mica substituted product prepared by substituting the interlayer ion of swellable synthetic mica with an alkaline earth metal or other metal ion by an ion exchange method. CONSTITUTION:Sodium tetrasilicic mica of swellable synthetic mica or sodium hectorite of swellable OH-type synthetic mica is converted to a substitution product wherein Al<3+> and Ti<4+> ions between layers of said mica are brought to a state of polynuclear hydroxide ions. Subsequently, the substitution product is heat-treated at 200-300 deg.C for 15-30min in air to prepare an adsorbent for a carcinogen. This adsorbent has a versatile high adsorbing ratio reaching 94-99% with respect to both substances of benz(alpha) pyrene and TrpP2. The aforementioned adsorbent can be used according to a column filter system, a system impregnating filter paper and a tea bag system, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial Application Field" The present invention relates to an adsorbent for carcinogenic substances that is based on a metal ion substituted product of swellable synthetic mica.

``Prior art and its problems'' Substances that cause malignant tumors when inhaled or ingested by animals, and substances that cause malignant tumors when repeatedly contacted with the skin surface over a long period of time are collectively referred to as 1.
As a result of numerous past studies,
It has been demonstrated that many types of such carcinogenic substances exist in the living environment.

That is, according to evidence from animal experiments, benz(α)pyrene, 3-methylcholanthrene, 9. Polynuclear aromatic hydrocarbons such as lO-dimethyl-1,2-benzanthracene have been shown to cause liver cancer and other malignant tumors in oral administration experiments, as well as O-aminoazotoluene and p-dimethylaminoazobenzene (Bataminilow). ), various aromatic amines and their derivatives such as 2-7cetylaminofluorene, and nitrosamines. Furthermore, when used in combination with the above carcinogenic substances, phenobarbital,
Phenol, urethane, etc. are known. 4-aminobiphenol, 2-naphthylamine, benzidine, and benzo(α)pyrene are well-known as substances that are particularly noteworthy for their carcinogenicity to the human body. Many carcinogenic substances are present in processed foods such as grilled fish, netteki, and hamburgers, caffeinated drinks such as tea and coffee, alcoholic drinks such as brandy, whiskey, and rum, and foods such as wild vegetables bracken. It has been known.

Therefore, the development of adsorbents that can efficiently remove these carcinogenic substances is a social need.

However, since the properties of carcinogenic substances generally vary widely, there are advantages and disadvantages in terms of performance depending on whether the adsorbent adsorbs the carcinogenic substance or the adsorbent. Currently, there are almost no examples of adsorbents that can universally adsorb carcinogenic substances.

To explain this using an actual example, cellulose exhibits high adsorption performance for benzo(α)pyrene, but it does not absorb the mutagen T in the water-soluble tryptophan pyrolysis product.
rpP2 (3-amino-1-methyl 5H-pyrido[4,
3-b] For indole, the adsorption capacity is significantly reduced.

Small amounts of sulfites, such as sodium sulfite, sodium hydrogen sulfite, potassium pyrosulfate, sodium dithionite and sulfite anhydride, are added as a means of inactivation to those in foods, resulting in the addition of =2 (So3') ions. However, since these agents are already used as food bleaches, preservatives, and antioxidants, there are naturally permissible limits to the amount they can be added. However, when it comes to luxury goods, it also has the disadvantage of affecting taste. The above drug requires 20 to 300 P to expect an inactivation effect.
It is necessary to dissolve a sufficient amount of the P layer, and if the dissolved concentration is diluted, the inactivation effect will be reduced, and the active substance of the carcinogenic substance, which is a mutagen, will still remain.

"Means for Solving the Problem" The present inventors focused on this point and as a result of intensive research, it was found that it is difficult to universally adsorb the carcinogenic substance using the single adsorption method described above. However, compounds in which interlayer ions of swellable synthetic mica are substituted with alkaline earth metal ions or metal ions by an ion exchange method can be processed under appropriate heat treatment conditions to eliminate water-soluble organic substances. It was discovered that water-soluble organic substances can also be adsorbed in a multifaceted manner, and the present invention was achieved.

In order to further clarify this, we will discuss the structure and characteristics of synthetic mica, which is the raw material of the present invention, and what kind of processing can be applied to the synthetic mica 11 to create an adsorbent with residues that adsorbs the carcinogen from multiple angles. Explain what you can get.

The raw material for the adsorbent of the present invention is synthetic mica that exhibits swelling properties and is obtained by a melt synthesis method, and has a so-called mica structure.
It is a crystalline substance exhibiting an amorphous layered structure, and differs from natural products in that it generally does not have an 10H group as a component of its crystal structure. That is, what corresponds to the crystal structure part of -OH in natural products is
It is composed of F. Incidentally, in recent years, trial production of -OH type (fluorine-free) synthetic mica has begun.In the present invention, swellable synthetic mica is used.

It may have either F or (OH)2 in its crystal structure.

The basic composition of such a series of synthetic mica can be expressed as a general formula expressed by the following formula (I).

×0.2~1.0 2.0~3.5"'4"10. (F
2 or (OH)2), Y (wherein,
.

+ + + 2+ 2◆Rb, Cs
, TI , Ca , Sr , and Ba 2+ , and represents one or more ions selected from the group consisting of , Y
Hahehedron position Neuonteatte, Mg", Li", Fe
”.

Ni”, Go”, Zn”, M?r”, Cu”, Cr
"7j-" represents one or more kinds of ions selected from the group consisting of
", B" represents one or more ions selected from the group consisting of "Fe", Cr3+, and V3+.

Figure 1 shows a cross-sectional model of the crystal of sodium taeniolite, which is a type of swellable synthetic mica.
2L1(Si,0,.)F2.

As shown in Figure 1, the crystalline unit layer of synthetic mica has SiO2 tetrahedrons connected to each other on the surface to form a flat plate, and between the two SiO flat plates is a crystal unit layer consisting of MgO and F2 as main components. It is a crystalline body with a three-layer structure filled with facet layers.

The total value of negative and positive charges in this unit layer is such that there is a slight surplus of negative charges, and in order to neutralize this charge, alkali ions are coordinated between the crystal layers, and many layers are stacked. It has a similar structure. The alkali ions (excluding K+) between these layers draw water molecules between the layers in a wet state, so the crystal exhibits the property of expanding in a wet state. The water is called r interlayer water 1.

This interlayer water, unlike crystal water, can freely dissolve ions. In addition, the alkali ions between the layers have ion exchange properties,
Can be replaced by ion exchange with cations, including other organic substances. Utilizing this property, it is possible to create a substituted product in which one of various cations is inserted between the layers of mica.

The adsorbent of the present invention can be produced by processing the above-mentioned 11-moisture synthetic mica to replace the interlayer alkali ions with metal ions or alkaline earth metal ions. Especially divalent, trivalent, which forms polynuclear hydroxide ions,
The present inventor has found that when substituted with a tetravalent metal ion, a porous body J made of an intercalation compound exhibiting various properties can be obtained by forming a substituted substance and then applying appropriate heat treatment. Utilizing this fact, et al. obtained a high-performance adsorbent for water-insoluble organic solvents and have already filed a patent application (Japanese Patent Application No. 187287-1987).

However, as an adsorbent for carcinogenic substances, it is desirable to have the property of absorbing both water-soluble and water-insoluble organic substances at the same time. As an example, "benz (α)"
Pyrene J and “TrpP in tryptophan pyrolysis products”
2j was selected, and the relationship between heat treatment conditions and adsorption rates of various substituents for these three substances was investigated (see FIGS. 2 and 3 showing the results of Examples).

As a result of the above experiment, regarding rbenz(α)pyrene,
Substitution products of trivalent and tetravalent metal ions with polynuclear hydroxide ions are effective, and although the characteristics differ slightly depending on the type of synthetic mica, they have a high level of performance under heat treatment conditions of 300°C to 600°C. It was found that the adsorption rate was as follows. Ca
2''', Ba''''1Mg2' ion substituted product is 300~
Under the treatment condition of 400°C, the adsorption rate is low, and when treated at aOO°C, it shows a good adsorption rate for water-insoluble organic substances.

On the other hand, for rTrpP2J (water-soluble), the high adsorption adsorption rate of both metal ion and alkaline earth metal ion substitutes is significantly reduced at a heat treatment temperature of 300 to 400°C.

As mentioned above, the principle by which the adsorption rate improves is not clear, but in the process of heat treatment at 200 to 300°C, the one-layer substituted material undergoes a change from dehydration to porous material, rapidly increasing the adsorption affinity for both substances. It is assumed that this increases the In particular, Al
31, Ti4+ substituted product forms a solid acid that acts as a proton donor or an electron acceptor, and is therefore considered to exhibit remarkable properties fl in the adsorption of polynuclear aromatic basic hydrocarbons.

In addition, the micropores of the intercalation compound formed during the dehydration process also exhibit adsorption on the inner surface of the pores for the mutagen TrpP2, which is a water-soluble decomposition substance. If heat treatment is applied to make it too strong,
Since this results in a decrease in adsorption of water-soluble substances, it is necessary to keep the heat treatment conditions at the low temperature end in the solid acid formation temperature range.

The adsorbent of the present invention may be used by any known method, for example, using a column filter, applying it to a filter paper + 1±'' I-poison, -par, h し乎纺 also 1 old, 1 pattern I ← / - Carcinogenic substances can be efficiently adsorbed and removed.

"Example" Next, Kinoi IJI will be further explained with reference to Examples, but the present invention is not limited to these Examples.

Example 1 An acidic titanium sulfate solution (2 mg T
Add about 200 ml of the HaOIl solution and FukuH
Add 2SO4 solution as needed to adjust the pH to 1.5~
Adjust to 1.8. Continue stirring for about 30 minutes,
Aggregates of synthetic mica substituted with titanium polynuclear hydroxide were obtained by ion exchange. The supernatant is discarded, and the aggregated substituents are isolated by means such as filtration or centrifugation (3000 rpm, 30 minutes). At this time, the method of dispersing and separating the substituted product in acidic water was repeated once or twice to wash away excess titanium ions. The thus obtained substituted product was air-dried at 80 to 100° C. for a day and night, and then pulverized to the extent that the agglomerates were removed to obtain approximately log of the substituted product in powder form. Approximately 2 g of this substituted product was placed in a magnetic crucible, transferred to a Matsufuru furnace equipped with an electronic temperature controller, and heat-treated at a predetermined temperature for approximately 30 minutes each in an air atmosphere. After the heat treatment was completed, the powder was left to cool in the air and then used as a sample for a carcinogenic substance adsorption test.

Example 2 By carrying out the same treatment as in Example 1, the substitution ions were changed to AI" (using aluminum chloride or aluminum nitrate, pH = 3.5 to 3.8), Zr" (
PH=1.5-1.9 using zirconium oxychloride
A wide variety of substituents were obtained with the following conditions: Ca'', M, 21'', Ba''''C neutral P).

Furthermore, by changing the type of swellable mica, many types of mica substitutes were obtained. Each of these samples was subjected to a prescribed heat treatment and then used as a sample for a carcinogenic substance adsorption test.

Example 3 - Commercially available “Rabonai” containing (OH)2 as a crystal structure component
J (Laporo Industries L
im1ted P, 0. Box13. KingSwa
y, Luton, Bedfordshire, LI
J48EW) powder and Kunimine Kogyo's "Kunivia Fj powder" are sodium hectorite (Na qMg2%Li3,1 (Si40..) F2 whose crystal structure component is F2.
(abbreviated as Ha-HT) belongs to montmorillonite-based swelling mica with the same structure.

An interlayer replacement body was produced in the same manner as in Example 1 using the above raw materials. However, as for V Laponite 1, the development and growth of the crystal structure is inferior, so the yield in the solid-liquid separation process of the substituted product by the same operation as in Example 1 is ``Sodium Hectorite 1'', ``Kunipia Fj's 5-10 These Ti polynuclear hydroxide substituted products were heated at 200°C to 4%.
After heat treatment at 00°C for 30 minutes, it was used as a sample for adsorption test of a carcinogenic substance.

Example 4 (1) Method of adsorption experiment 0.2 XIG of benz(α)piL/7, dirpF2
-10% of the sample obtained in Examples 1 to 3 above was added to 11% of the 6M solution.
Add 1 mg to 1 mg and leave to stand for 30 minutes with occasional shaking.

The supernatant liquid was used as the measurement sample.

(2) Method for analyzing benz(α)pyrene 0.21 l of dimethyl sulfoxide was added to 0.2 l of the sample solution, and the fluorescence intensity at a fluorescence wavelength of 410 nm at an excitation wavelength of 368 nm was measured using a fluorescence spectrophotometer.

(3) TrpP2 measurement method Using a sample solution of 0.21, measurement was performed in the presence of rat liver homogenate by a mutagenicity assay (Ames method) using Salmonella typhimurium TA98 strain.

(4) Calculation method for adsorption rate Adsorption rate of benz (α) pyrene = [(A - peak height of benz (α) pyrene in solution with adsorbent added) / peak of benz (α) pyrene in solution without adsorbent Height A) )]
X100 Trp F2 adsorption rate = (B-old S of adsorbent added solution
+Number of mutant colonies/old S mutant colony a(B) X 100 of solution without adsorbent The results are shown in FIGS. 2 and 3.

Example 5 ■ Sodium hectorite [(F type) swellable mica], ■
Knivia F [purified natural montmorillonite, (OH type) swellable mica] and Laponite [(OH) type swellable mica] were added to each polynuclear hydroxide substituted product at 300 to 400°C.
Collect 20 layers (g) of powder that has been heat-treated for 30 minutes, and fill this powder 3 into the leg tube 2 of a glass-shaped microfunnel 1 shown in Figure 4. 4 in Figure 1 is glass cotton. show.

From the top of the funnel, benz(α)pyrene, Trp F2 0
．． 2 ml of 2.times.10.sup.-8 M solution was added dropwise, and the 0-pass liquid that had passed through the packed column was collected in a glass dish, used as a measurement sample, and the adsorption rate was measured by the method of Example 4.

The results showed that each of the powders ■, ■, and ■ had an adsorption rate of 99.5% or more for both benz(α)pyrene and Trp F2.

Example 6 The adsorption rate of carcinogenic substances of the adsorbent used in Example 5 was measured by the method of Example 4 by equilibrium adsorption. However, in order to improve the detection sensitivity, the concentration of TrpP-2 was adjusted to 2XlO-6M (0.2XlO in Example 4).
'M) was used. Furthermore, the amount of adsorbent used was set to 10 g/ml and 5 mg/l of layer, and the adsorption rate at which the amount of adsorbent used was reduced to 1/2 was also measured. The heat treatment conditions were 380°C and 500°C. The results are shown in the table below.

*marked is 380℃ heat treated product, ■ mark is 500℃ heat treated product The above results revealed the following.

(1) Even if the mica crystal structure is F2 type (OH)
Even in type 2, if the crystal structure is the same, there is almost no difference in adsorption performance.

(2) Even when the amount of adsorbent used was reduced to 1/2 to 10 g/l and 5 g/sl, no significant decrease in adsorption efficiency was observed and good performance was exhibited.

(3) When subjected to heat treatment, both non-hydrophilic benzo(α)pyrene and hydrophilic TrpP-2 exhibited high adsorption performance.

``Effects of the Invention'' As described above, the adsorbent of the present invention exhibits a multifaceted high adsorption rate for a single carcinogenic substance. Between the layers of sodium hectorite,
, after making the T14+ ion a substituent in the state of polynuclear hydroxide ion, the 2° adsorbent in air has 84-9
It showed a multifaceted high adsorption rate of up to 9%. This has a high performance that cannot be found in conventionally known silica gel, cellulose, γ-alumina, etc., and has the ability to adsorb both water-insoluble and water-soluble carcinogenic substances in a multifaceted manner. has.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional model of lithium taeniolite, FIGS. 2 and 3 are graphs showing the results of the examples, and FIG. 4 is a cross-sectional view of the microfunnel used to measure the adsorption rate. Patent Applicant Topy Industries, Ltd. Japan Tobacco Inc. Agent Patent Attorney Hitoshi Inagaki Yoshipa Figure 1 Iwa○○・○0 0Mg5iLiF Figure 2 (0n) Suha pressure fork ('C) Figure 3 4Figure 3()mrn□ \Mawari Nini/

Claims (4)

[Claims] (1) An adsorbent for carcinogenic substances whose main material is a substituted synthetic mica obtained by replacing the interlayer ions of swellable synthetic mica with alkaline earth metal or other metal ions using an ion exchange method. (2) The adsorbent according to claim 1, wherein the ions to be exchanged are alkaline earth metal or other metal ions that form soluble polynuclear hydroxide ions. (3) The adsorbent according to claim 2, which is obtained by further subjecting the synthetic mica substitute to heat treatment. (4) The adsorbent according to any one of claims 1 to 3, wherein the swellable synthetic mica used as a raw material has F_2 or (OH)_2 as a crystal constituent component.