JPH10216511A - Chemical for adsorption separation and adsorption separation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To heighten the mechanical strength of a chemical for adsorption separation and efficiently carry out adsorption separation of optical isomers by using an agent for adsorption and separation produced by immobilizing an optically active organic compound on a zeolite. SOLUTION: A chemical for adsorption separation of optical isomers such as optically active amino acids, carboxylic acids, etc., to be used for agrochemicals, pharmaceuticals, and food additives, etc., is produced by immobilizing an optically active organic compound in a zeolite. The optically active organic compound is a compound having one or more optically active sites, and amino acids, optically active amines, optically active carboxylic acids are cited and the optically active amines are especially preferable. As the zeolite, a zeolite ion-exchanged by a transition metal ion is preferable and a faujasite type zeolite and a β type zeolite are especially preferable. Further, the mole ratio of cation in the zeolite or the chemical for adsorption separation to the optically active organic compound to be immobilized is controlled to be 0.01-4, and preferably 0.01-2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical isomer adsorption / separation agent and an adsorption separation method.

[0002] Optical isomers are widely used as various chemical products such as agricultural chemicals, pharmaceuticals, food additives and intermediates thereof.

Specifically, optically active amino acids, amino acid derivatives, carboxylic acids, carboxylic acid derivatives, amine-containing compounds, alcohol compounds, hydroxycarboxylic acids,
And hydroxycarboxylic acid derivatives.

[0004]

2. Description of the Related Art Conventionally, zeolite has been widely used industrially as an adsorbent and separation agent for geometric isomers. For example, U
SORBEX represented by OP company's PAREX process
Separation by the apparatus of DB (Brownton,
Separation science and t
technology, 19, 723-236p (198
4-1985)), an aromatic isomer such as p-xylene and an isomerized saccharide are separated using a faujasite-type zeolite-adsorbing and separating agent.

In the separation of optical isomers, polysaccharide derivatives (esters or carbamates such as cellulose and amylose) and polysaccharide derivatives supported on silica gel, cyclodextrin derivatives, and cyclodextrin derivatives supported on silica gel, etc. A polyacrylolate derivative, a polyacrylolate derivative supported on silica gel, or the like can be used as the adsorption separating agent. Separation of optical isomers using polysaccharide derivatives was reported by Yashima and Okamoto (Bull. Chem. So
c. Jpn. , 68, 3289-3307 (1995).
Have been.

[0006]

However, in conventional industrial adsorption separation processes, separation of geometric isomers such as xylene isomers using zeolites is known. However, optical isomers are separated using zeolites. No attempt has been known to separate them.

[0007] Furthermore, in the separation of optical isomers using an adsorption / separation agent in which a polysaccharide derivative or the like is supported on silica gel, these adsorption / separation agents have low mechanical strength and are difficult to use in an industrial separation process. Was. Furthermore, the preparation of these adsorbents is long and very expensive,
In addition, since only the polysaccharide derivative is supported, there is a problem that the polysaccharide derivative is eluted in long-term use. In addition, since there is no adsorbing and separating agent capable of separating all of a large number of optical isomers, various new adsorbing and separating agents have been studied.

[0008] In order to cope with such various problems, a novel adsorptive separating agent for optical isomers having a different chemical structure from the existing adsorptive separating agent and having different separating characteristics. There has been a demand for an adsorptive / separating agent which has high mechanical strength and can be easily prepared, and an adsorptive / separation method therefor.

[0009]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies on the adsorptive separation agent for optical isomers and the adsorption separation method. It has been found that this is a novel adsorption / separation agent preferable for adsorption / separation, and that the adsorption / separation method using this adsorption / separation agent is an excellent method.

That is, the present invention provides an adsorption / separation agent in which an optically active organic compound is immobilized on zeolite, a method for adsorptive separation of optical isomers using the adsorption / separation agent, and treatment of zeolite and an optically active organic compound in a solvent. And a method for producing an adsorption / separation agent.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

The zeolite in the present invention is what is called a molecular sieve, and is a crystalline inorganic porous material having a three-dimensionally regular space. Generally, zeolite refers to crystalline aluminosilicates such as faujasite-type zeolite, β-type zeolite, mordenite-type zeolite, pentasil-type zeolite, crystalline aluminophosphate, silica aluminophosphate, and the like. In particular, in the present invention, faujasite-type zeolites and β-type zeolites are preferred. Since the zeolite serves as a base for capturing the optically active organic compound, the adsorptive / separating agent of the present invention has excellent mechanical strength and is a preferable material for industrial use. Normally, zeolite is preferably used after being molded using a binder such as silica, alumina, or Benton for industrial use.
In the present invention, a molded zeolite or a powdered zeolite may be used, but a molded zeolite is particularly preferable. The particle radius of the molded article is preferably 1 mm or less.

The cation of the zeolite in the present invention may be a proton capable of forming a counter ion with an optically active amine, an amino acid, an optically active amine, an optically active carboxylic acid, an optically active hydroxycarboxylic acid, an optically active alcohol or a derivative thereof. A transition metal cation that easily forms a complex is preferable.

The optically active organic compound in the present invention is
It refers to a compound having one or more optically active sites irrespective of a natural type or a non-natural type. For example, it is an amino acid, an optically active amine, an optically active carboxylic acid, an optically active hydroxycarboxylic acid, an optically active alcohol or a derivative thereof. Particularly, an optically active amine is preferable. The higher the optical purity of these optically active organic compounds, the better,
Even if it is lower, there is no problem because the effect of the present invention is exhibited. It is preferably at least 30% ee (enatiomer excess), more preferably at least 50% ee, particularly preferably at least 90% ee.

The term "immobilization" in the present invention refers to a state in which an optically active organic compound is bonded to a local site of zeolite by an ionic bond, a complex bond or a covalent bond. Especially,
In the present invention, ionic bonds and complex bonds are preferred, and ionic bonds are particularly preferred. Since the optically active organic compound is firmly bound to the base of the zeolite like the adsorbent in the present invention, there is an advantage that elution of the optically active organic compound which is a separation recognition point by an eluent or the like can be prevented in advance.

In the case of a basic optically active substance such as an optically active amine, it is preferable to previously fix zeolite in an acidic state and then form an ion pair with the optically active amine to immobilize the zeolite.

For example, an ion pair can be formed and immobilized by proton-type zeolite and optically active amine obtained by ion-exchanging zeolite with an ammonium chloride aqueous solution and then calcining.

It is also preferred that the zeolite be ion-exchanged with a metal ion capable of forming a complex, and then an optically active organic compound coordinated to the metal ion be added to immobilize the metal ion.

The metal ions capable of forming a complex are preferably transition metal ions, for example, Cu ions, Zn ions,
Ni ion, Co ion, Cr ion, Fe ion, S
Examples include c ion, Ti ion, V ion, Mn ion, In ion, Sn ion, metal ions belonging to the same family as these metal ions in the long-periodic element table, and lanthanoid-based and actinoid-based metal ions.

The concept of the present invention is to form a chiral space in the zeolite pores by forming a complex or an ion pair between the cation and the optically active organic compound in the zeolite or the adsorbing / separating agent, so that they can be separated. It consists in separating optical isomers. The chiral space in the zeolite pores created by the optically active organic compound forming a complex or counter ion with the cation serves as a separation recognition field for the optical isomer.

Therefore, the ratio of the number of moles of the cation in the zeolite or the adsorbent / separating agent to the number of moles of the optically active organic compound to be immobilized affects the adsorption and separation. If the molar ratio is too small, the separation becomes poor because the chiral space is too small, and if it is too large, the adsorption space for the separation target is lost, which is not preferable. If the pores of the zeolite are sufficiently large and the optically active organic compound can be sufficiently accommodated, up to 4 molecules of the optical isomer can be coordinated per cation. The ratio of the number of moles of the cation in the medium or in the adsorptive separation agent is at most 4. In the present invention, the ratio of the number of moles of the cation in the zeolite or the adsorptive separating agent to the number of moles of the optically active organic compound to be immobilized is preferably from 4 to 0.01, more preferably from 2 to 0.01. This molar ratio is determined by the amount of cations in the adsorbent and C,
It can be easily measured by measuring the amounts of H and N. When the optically active organic compound dissolved in the solvent and the zeolite are mixed, and the solvent is evaporated to dryness to prepare an adsorbent, the amount can be calculated from the charged amount.

The optical isomer to be separated includes an amino acid, an optically active amine, an optically active carboxylic acid, an optically active hydroxycarboxylic acid, an optically active alcohol or a derivative thereof. Derivatives are preferred.

As a technique for the adsorption separation using the method of the present invention, a batch method by a so-called chromatography method, or an adsorption separation method by a moving bed or a simulated moving bed in which the method is continuous is preferable. In particular, a continuous adsorption separation technique using a simulated moving bed is preferable as an industrial process. As the basic operation of the adsorption separation by the simulated moving bed system, the following adsorption operation, concentration operation and desorption operation are continuously circulated and performed.

(1) Adsorption operation: The substance to be separated comes into contact with the adsorbing and separating agent, and the strongly adsorbed component is adsorbed while selectively leaving the weakly adsorbed component. The strongly adsorbed component is recovered together with the desorbent as an extract component.

(2) Concentration operation: The raffinate containing a large amount of weakly adsorbed components is further contacted with an adsorbent, and the strongly adsorbed components are selectively adsorbed, so that the weakly adsorbed components in the raffinate are highly purified.

(3) Desorption operation: The highly adsorbed weakly adsorbed component is recovered as a raffinate, while the strongly adsorbed component is expelled from the adsorbent by the desorbent and recovered as an extract component with the desorbent.

In this method, the components obtained from the extract can be highly purified. Further, after the undesired isomer is recovered, it can be isomerized (racemized in the case of an optical isomer) and returned as an adsorbed separation product.

The adsorbent in the present invention can be obtained by mixing zeolite and an optically active organic compound, but it is particularly preferable to treat the adsorbent in a solvent for uniform immobilization.

The solvent is not particularly limited, but is preferably a solvent that can sufficiently dissolve the optically active organic compound. For example, water, methanol, ethanol, chloroform, methylene chloride, benzene, toluene and the like can be mentioned.

[0030]

Next, the effects of the present invention will be described with reference to examples.

In the embodiment, the characteristics of the adsorbent are represented by the following adsorption selection coefficient αA / B.

ΑA / B = (adsorption phase A / adsorption phase B) / (liquid phase A / liquid phase B) Here, A and B indicate the concentrations of the respective components. The adsorption selectivity can be easily calculated by analyzing the concentration of each component in the liquid phase by gas chromatography.

When αA / B is larger than 1, the component A is adsorbed, and when αA / B is smaller than 1, the component B is adsorbed. Further, as this value is larger than 1, the smaller the value of A and B, the closer to 0, the easier the adsorption and separation of A and B become.

The adsorption capacity in the examples was calculated from the change in the concentration of the liquid phase using the internal standard (n-nonane).

Although the adsorption selection coefficient in this embodiment is measured under static conditions, it can be regarded as substantially the same as the so-called adsorption selection coefficient obtained by another evaluation method such as a flow-through method. For this reason, those having a difference in the adsorption selectivity can be separated by a chromatography method using a substantially batch system or a moving bed system.

(Preparation of zeolite adsorbent on which optically active organic compound is immobilized) (1) Preparation of proton type Y zeolite As the zeolite, 4.8 NaY manufactured by Tosoh Corporation was used.
As a result of atomic absorption analysis, the composition of this zeolite was Na56Si
136Al56O384 (formula weight = 12761.79). 4.8N
10.0 g of aY was added to 100 g of a 2N aqueous solution of ammonium chloride (manufactured by Tokyo Chemical Industry) and heated at 80 ° C. for 30 minutes. Thereafter, the zeolite was filtered off. This operation was repeated five times. Thereafter, zeolite was added to about 100 g of water, heated at 80 ° C. for 30 minutes, and then the zeolite was separated by filtration.
This operation was repeated five times. Then, it is dried at 120 ° C. for 12 hours, further at 300 ° C. for 1 hour, and then at 500 ° C.
For 2 hours, and proton-type Y zeolite (4.8 H
Y).

(2) Preparation of Y-type zeolite adsorbent on which L-methylbenzylamine was immobilized 4.8 HY (10 g) was added to 200 g of chloroform (manufactured by Tokyo Chemical Industry) dried by molecular sieve. afterwards,
L-methylbenzylamine (manufactured by Tokyo Chemical Industry, 98% ee)
0.10 g was added. After stirring at room temperature for 3 hours, chloroform was concentrated and dried under reduced pressure, and further vacuum-dried at 50 ° C. for 12 hours to obtain a Y-type zeolite adsorbent on which L-methylbenzylamine was immobilized. In the same manner, the amount of L-methylbenzylamine was adjusted to 0.25, 0.50, 0.7
5, 1.00, 1.25, 1.50 and 1.80 g were changed to prepare adsorbents having different amounts of immobilization. Dissolve each adsorbent in a water / methanol mixed solvent and adjust the pH
When the pH in the solvent was measured with a test paper, it was almost 7. From this result, it was found that all L-methylbenzylamine was immobilized in the zeolite. As can be seen from the above examples, the adsorbent in the present invention can be adjusted very easily.

(3) Preparation of Cu ion-exchanged Y-type zeolite adsorbent on which (S, S) -1,2-diaminocyclohexane is immobilized Cu ion-exchanged Y-type zeolite is NaY (manufactured by Tosoh Corporation)
(Silica / alumina = 4.8 (mol / mol)) by ion exchange. After ion exchange with a saturated aqueous solution of copper nitrate (manufactured by Wako Pure Chemical Industries, Ltd.) 10 times the weight of NaY, the mixture was washed five times with water. Then, at 120 ° C for 2 hours,
Furthermore, it dried at 300 degreeC for 2 hours, and was set as Cu ion exchange Y-type zeolite.

0.2 g of (S, S) -1,2-diaminocyclohexane (manufactured by Toray Industries, 99% ee or more) was dissolved in 10 ml of chloroform, and 1.00 g of a Cu ion-exchanged Y-type zeolite was added thereto. After stirring at room temperature for 1 hour, the solid was filtered off and washed with water. After vacuum drying at 60 ° C. overnight, a Cu ion-exchanged Y-type zeolite adsorbent on which (S, S) -1,2-diaminocyclohexane was immobilized was used. Because the color of the solid surface has changed compared to before immobilization,
The coordination environment around the Cu ion changes, that is, (S,
It was found that S) -1,2-diaminocyclohexane was coordinated.

(Evaluation of Adsorption Separation Performance) Adsorption and separation of DL-mandelic acid (Examples 1 to 8, Comparative Example 1) 5.0 g of 0.2 g of DL-mandelic acid (manufactured by Tokyo Chemical Industry Co., Ltd.)
Dissolved in 1 liter of ethanol. This was placed in a stainless steel autoclave having a capacity of 30 ml, and a Y-type zeolite adsorbent 1.0 having L-methylbenzylamine immobilized thereon was further added.
Then, 0 g and 0.2 g of n-nonane (manufactured by Nacalai Tesque, Inc.) as an internal standard substance were added thereto, followed by sealing. Left at room temperature for 2 days. The autoclave was shaken vigorously up and down once every 5 hours to ensure even contact between the solid and liquid portions. Thereafter, the supernatant was taken out and subjected to liquid chromatography (OA5000 column (manufactured by Sumitomo Chemical Co., Ltd.), eluent: acetonitrile / 2 mM copper sulfate aqueous solution = 30/7).
0, feed rate: 1.0 ml / min).
Table 1 shows the obtained results. It can be seen that increasing the amount of L-methylbenzylamine immobilized increases the adsorption selectivity and improves the separation performance. The adsorption capacity is maximized when the immobilization amount is 5%, and decreases as the amount is further increased. The number of moles of L-methylbenzylamine in the table and
The ratio of the number of moles of cations in 4.8HY is H56S
It is converted as i136Al56O384. This ratio is
It can be seen that adsorption selectivity is expressed at 0.01 or more.

2. Adsorption separation of DL-methyl mandelate (Examples 9 to 16, Comparative Example 2) Adsorption separation performance was evaluated by the same method as that for DL-mandelic acid. Table 2 shows the obtained results. This experiment also showed that adsorption selectivity was obtained. In addition, the thing made from Tokyo Chemical Industry was used for DL-methyl mandelate.

3. Adsorption separation of methyl DL-2-chloropropionate (Examples 17 and 18) (Example 17) Methyl DL-2-chloropropionate (manufactured by Tokyo Kasei): n-nonane (Nacalai Tesque, Inc.) Made)
1.00 g of a 1: 9 (weight ratio) solution was weighed, and 1.00 g of a Cu ion-exchanged Y-type zeolite adsorbent having (S, S) -1,2-diaminocyclohexane immobilized thereon was weighed.
In addition, it was sealed. After adsorbing for 2 hours while stirring periodically at room temperature, the supernatant was taken out and subjected to gas chromatography (Chiraldex B-TA capillary column (AS).
TEC))). Adsorption selection coefficient αR / S
Was 1.09. From this example, it was confirmed that an adsorbent in which an optically active compound was coordinated to a zeolite ion-exchanged with a transition metal ion identified an optical isomer and exhibited adsorption selectivity.

Example 18 Evaluation was performed in the same manner as in Example 17 except that the adsorption temperature was changed to 70 ° C. The adsorption selection coefficient αR / S was 1.09. From this embodiment, the seventeenth embodiment
Similarly to the above, it was confirmed that an adsorbent in which an optically active compound was coordinated to zeolite ion-exchanged with a transition metal ion identified an optical isomer and exhibited adsorption selectivity.

4. Comparative Example 3 Commercially available column for optical isomer analysis CHIRALCEL C
A filler (triacetyl cellulose) of 1.0 g was extracted from A-1 (manufactured by Daicel Industries, Ltd.), and the same experiment as in Comparative Example 1 was performed, but the adsorption selectivity was 1.00. As can be seen from this, it can be seen that the novel adsorbent of the present invention has different adsorption characteristics as compared with the existing adsorbent.

[0045]

According to the present invention, optical isomers can be separated by using an adsorption / separation agent in which an optically active organic compound is immobilized on zeolite.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI C07B 57/00 310 C07B 57/00 310 // C07M 7:00

Claims (9)

[Claims] 1. An adsorption separation agent comprising an optically active organic compound immobilized on zeolite. 2. The adsorptive separation agent according to claim 1, wherein the optically active organic compound is an optically active amine. 3. The adsorptive separation agent according to claim 1, wherein the zeolite is a zeolite ion-exchanged with a transition metal ion. 4. The zeolite according to claim 1, wherein the zeolite is a faujasite-type zeolite and / or a β-type zeolite.
The adsorption / separation agent according to any one of the above. 5. The method according to claim 1, wherein the ratio of the number of moles of the optically active organic compound to the number of moles of the cation or the protic cation in the zeolite or the adsorptive separation agent is in the range of 4 to 0.01. The adsorption / separation agent according to any one of the above. 6. A method for adsorptive separation, comprising adsorbing and separating optical isomers using the adsorptive separation agent according to claim 1. 7. The adsorption separation method according to claim 6, wherein the optical isomer to be separated is a compound containing a carboxylic acid or a derivative thereof. 8. The adsorption separation method according to claim 6, wherein the adsorption separation method is a batch type and / or a moving bed type. 9. The method according to claim 1, wherein the zeolite and the optically active organic compound are treated in a solvent.