JPH0329442B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] This invention relates to a method for adsorbing and separating oxides, and more specifically, when separating oxides from a solution containing oxides, by using a specific adsorbent, for example, epoxy The present invention relates to a method for adsorbing and separating oxides that can efficiently adsorb and separate oxides under mild conditions without ring opening. [Prior Art and its Problems] Conventionally, as a method for separating oxides from a solution containing oxides, for example, a distillation method and an extraction method are known. On the other hand, oxides are highly reactive and are easily decomposed by the action of acids, alkalis, metals, heat, etc.;
It has the property of easily reacting with -OH groups, -COOH groups, etc. Therefore, it is preferable to separate the oxides under mild conditions. However, when separating oxides using conventional distillation methods, it is necessary to perform the separation operation at relatively high temperatures, so some of the oxides are decomposed by the heat, making it difficult to recover oxides with a high recovery rate. The problem was that it was not possible to separate the classes. Furthermore, when oxides are separated by conventional extraction methods, side reactions may occur and by-products may be generated due to the use of solvents. Therefore, there was a problem that this by-product had to be removed in order to obtain pure oxide. Furthermore, in both the distillation method and the extraction method, there is a problem in that the operation for separating oxides is relatively complicated. This invention has been made based on the above circumstances. [Objective of the Invention] The object of the present invention is to solve the above-mentioned problems, to eliminate problems such as decomposition of oxides due to heat and generation of by-products due to the use of solvents, and to produce oxides with a high recovery rate through simple operations. An object of the present invention is to provide an industrially advantageous adsorption/separation method for oxides that can separate oxides. As a result of extensive research in order to achieve the above object, the inventor discovered that the above object could be achieved by using a specific adsorbent,
We have arrived at this invention. [Means for achieving the above object] The gist of this invention for achieving the above object is as follows:
A method for adsorbing and separating oxides from a solution containing oxides, which is characterized by using crystalline silica and/or crystalline metal silicate as an adsorbent. In this invention, crystalline silica and/or crystalline metal silicate is used as the adsorbent. Examples of the crystalline silica include naturally occurring quartz, lepidolite, and cristobalite, and artificially synthesized coesite (silica C), stishyovite, silica K, and silica W. As the crystalline _{metal silicate} , for example, _the formula _{[ 1} ]; (Varies depending on the type of M, the value of
One or more metal elements selected from the group consisting of La, Sc, Y, Cr, and Ti, and
X, that is, the molar ratio (SiO ₂ /M ₂ O ₃ ) is 10 or more,
Examples include crystalline metal silicates having a crystalline cavity structure of preferably 15 or more and having cation exchange ability. Here, if the molar ratio (SiO ₂ /M ₂ O ₃ ) is less than 10, the recovery rate of oxides may be low, which is not preferable. Note that this also includes H-type zeolite. Among these, ZSM with a main cavity of 10-membered oxygen ring
Crystalline metal silicates belonging to zeolites of -5 type structure, ie metal silicates of pentasil type structure, are preferred. Examples of such crystalline metal silicates include ZSM-5, which is described in Japanese Patent Publication No. 46-10064 and U.S. Pat. No. 3,790,471 when M is Al; ZSM-8 described in Japanese Patent Publication No. 53-23280, ZSM-35 described in Japanese Patent Application Publication No. 52-139029, etc., and U.S. Patent No. 4001346.
Crystalline aluminosilicate such as _ZSM - _{21 described} in
The above can be suitably used. Also, as an example where M is Fe, Journal of Catalysis No. 35
There are crystalline iron silicates such as ferrite, which is described in Vol. 256-272 (1974), JP-A-50-127898 or JP-A-55-85415. Examples of M being Ga include crystalline gallosilicates such as gallosilicates having a ZSM-5 type structure. M is B, In, La, Sc, Y, Cr, Ti
An example of this is a crystalline metal silicate having a structure in which trivalent B, In, La, Sc, Y, and Cr ions are substituted in the crystalline aluminosilicate. Among these, M in the above formula [1] is Al, Ga, Fe
is preferable, and Al is particularly preferable. The crystalline metal silicate used in the method of this invention can be prepared by a known method. For example, as a method for synthesizing the ZSM-5 type zeolite or pentasil type crystalline metal silicate, in the presence of a tetraalkylammonium halide having 2 to 5 carbon atoms or other amines, colloidal Silicic acid or its condensates, such as silica or water glass, or silicates, as a source of metal oxides (M ₂ O ₃ ), such as aluminum sulfate, gallium nitrate, ferric sulfate, chromium sulfate, sodium aluminate, etc. It is known that it can be prepared by hydrothermal synthesis using a mixture whose main components are salts such as sulfates, nitrates, or oxyacids of the metal element M. Also known is a method in which an alkali metal hydroxide such as sodium or an alkali metal compound such as a halide is allowed to coexist during the hydrothermal synthesis. The crystalline metal silicates obtained by these methods are generally not in the H ⁺ form, but in the 4+ form instead of H ⁺ .
Since the alkali metal ions such as class ammonium ions and/or Na ⁺ have been substituted, it is preferred to convert this into the H ⁺ form. This conversion can be easily accomplished by known methods. For example, it is known that converting quaternary ammonium ions to H ⁺ can be achieved by calcination in air at a temperature of approximately 500-600°C, while converting alkali metal ions such as Na ⁺ to H ⁺ For example, a method is often used to obtain an ammonium salt type crystalline metal silicate by treating an alkali metal salt type crystalline metal silicate with an aqueous solution of an ammonium salt such as ammonium nitrate or ammonium chloride. In addition to these methods, a method of directly treating with dilute acid such as dilute hydrochloric acid can also be used. Various methods other than these are known as methods for synthesizing crystalline metal silicates. The crystalline metal silicates used as adsorbents in the method of this invention can be synthesized by any of these methods, and the invention is not limited to the use of adsorbents by any particular method of preparation. In addition, in this invention, the crystalline metal silicate is
Although the H ⁺ type is preferred, H ⁺ in the adsorbent may be replaced with other cations such as ammonium ions, sodium ions, calcium ions, etc., as long as the object of the present invention is not impaired. The shape of the adsorbent in this invention may be any shape such as fine powder, granules, strips, spheres, and pellets. In this invention, the crystalline metal silicate is preferably calcined in a stream of inert gas such as air and/or nitrogen before the reaction in order to improve the activity of the adsorbent. The firing conditions depend on the type of crystalline metal silicate,
Although it varies depending on the degree of residual quaternary ammonium ions and structured water, sufficient activity can be obtained by heating at a temperature of usually 400 to 600°C, preferably 450 to 550°C for 1 hour or more, preferably 3 hours or more. is obtained. In this invention, at least one or a mixture of two or more of the crystalline silica and crystalline metal silicate can be used as the adsorbent. Specific examples of the oxides include various oxides represented by any of the following formulas [2] to [6]. Formula [2]; (However, in formula [2], R ¹ and R ² each represent hydrogen and/or an alkyl, an alkene, and a halogen-substituted product thereof such that R ¹ and R ² have 1 to 18 carbon atoms.) Formula [ 3]; (However, in formula [3], X is hydrogen, halogen, -OH,
_-OCH3 represents any one of alkyl, _-NH2 , -SH, and _-SCH3 , and q and n are each an integer in which q+n falls within the range of 0 to 16. ) Equation [4] and Equation [5]; (However, in formula [4] and formula [5], R ¹ and R ² are alkyl, alkene, benzene, cycloalkane,
and any of its halogen-substituted products,
P is an integer within the range of 1-6. ) Formula [6]; (However, in formula [6], Y represents either halogen or alkyl.) In the method of the present invention, among oxides, epoxides such as those represented by the above formulas [2] to [6] are particularly used. It can be suitably adsorbed and separated. In this invention, the oxide-containing solution is
3 or higher, and the adsorption reaction of oxides by the crystalline silica and/or the crystalline metal silicate is preferably allowed to proceed at a reaction temperature of 80° C. or lower. The pH of the oxide-containing solution is 3
If the size is smaller, the oxides in the solution may be decomposed by the acid or may react with the acid to produce by-products. Furthermore, if the reaction temperature exceeds 80°C, oxides may be decomposed by heat.
Here, in order to adjust the pH of the oxide-containing solution, a buffer such as a phosphate buffer or a glycine buffer may be used as necessary. A recovery solvent is used to recover the oxides adsorbed on the crystalline silica and/or the crystalline metal silicate. Examples of the recovery solvent include methanol,
Ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, pentanol, pentanol-1, pentanol-2, pentanol-3, 2-methylbutanol-1,2- Methylbutanol-2, 2-methylbutanol-3,2
-Alcohols such as methylbutanol-4, dimethylpropanol; Alkali such as methane, ethane, propane, butane, pentane, hexane, heptane, octane, nonane, decane, undecane, dodecane; ethene, propene, butene-1, pentene-1 , hexene-1, heptene-1, octene-1, nonene-1, decene-1, undecene-1
1, alkenes such as dodecene-1; ketones such as acetone, methyl ethyl ketone, pyruvic acid, acetoacetic acid, and levulinic acid; aromatic solvents such as benzene and toluene; and cyclohexane. In this invention, the crystalline silica and/or crystalline metal silicate used as an adsorbent can be effectively used as an adsorbent repeatedly until it is destroyed and lost by performing a calcination operation. [Effects of the Invention] According to the method of the present invention, when separating oxides from an oxide-containing solution, crystalline silica and/or crystalline metal silicate is used as an adsorbent, so conventional distillation methods and extraction methods are not required. Oxides can be separated and recovered under milder conditions compared to conventional methods. Therefore, according to the method of this invention,
If some of the oxides are decomposed by heat, as in the case of conventional distillation methods, there will be no residue, and as in the case of conventional extraction methods, the solvent and oxides may react and produce side effects. It cannot be produced by living things. Therefore, according to the method of the present invention, it is possible to provide a method for adsorbing and separating oxides that has a high recovery rate of oxides and is easy to operate. Furthermore, since the adsorbent used in the method of the present invention can be effectively used as an adsorbent any number of times by repeating the calcination operation, the present invention provides an economically advantageous method for adsorbing and separating oxides. Can be done. [Example] Examples of adsorbent preparation, examples, and comparative examples in the method of the present invention are shown below. Adsorbent preparation example 1 Aluminum sulfate (18 hydrate) 16.92g, sulfuric acid
Solution A was prepared by dissolving 15.0 g of tetranormal propylammonium bromide and 26.3 g of tetranormal propylammonium bromide in 250 ml of water. In addition, water glass (SiO ₂ 29.0% by weight, Na ₂ O 9.4
Solution B was prepared by dissolving 211 g (wt%, water 61.6 wt%) in 250 ml of water. Furthermore, add 79.0g of NaCl to 122g of water.
ml to prepare Solution C. After gradually dropping and mixing Solution A and Solution B into Solution C, 3.0 g of 50% sulfuric acid was added to the mixed solution and stirred to adjust the pH to 9.5. Subsequently, the obtained aqueous mixture was placed in an autoclave having a volume of 1, and a reaction was carried out for 20 hours at a temperature of 170° C. under autogenous pressure while stirring. After cooling the reaction mixture, the product was washed 5 times with 1.5 g of water. The solid content was then separated by filtration and dried at 120° C. for 6 hours to obtain 56 g of crystalline metal silicate. The composition ratio (molar ratio) of this product is 0.3Na ₂ O・
It was 1.1 (TPA) ₂ O・Al ₂ O ₃・38.OSiO ₂・4.9H ₂ O. TDA here refers to a tetranormalpropylammonium group (hereinafter sometimes simply referred to as TPA). Further, this crystalline silica was calcined in air at 550° C. for 6 hours, and then ion exchanged overnight at room temperature using 5 ml of 1N ammonium nitrate solution per 1 g of the silica. Next, it was washed three times using 1.5% pure water and dried at 120°C for 6 hours.
It was further dried at 550°C for 6 hours to obtain a crystalline metal silicate adsorbent. Adsorbent preparation example 2 Aluminum sulfate (18 hydrate) 7.52g, 97% sulfuric acid
17.6g, tetranormal ammonium bromide
Solution A was prepared by dissolving 26.3g in 250ml of water. In addition, liquid B and liquid C similar to those in Adsorbent Preparation Example 1 were prepared. Gradually dropwise mix liquid A and liquid B into liquid C, then add 5.0 g of 50% sulfuric acid and stir to adjust the pH.
Prepared at 9.5. Subsequently, the obtained aqueous mixture was placed in an autoclave having a volume of 1, and a reaction was carried out for 20 hours at a temperature of 170° C. under autogenous pressure while stirring.
After cooling the reaction mixture, the product was washed 5 times with 1.5 g of water. The solid content was then separated by filtration and dried at 120° C. for 6 hours to obtain 53 g of crystalline metal silicate. The composition ratio (molar ratio) of this product is 0.5Na ₂ O・1.6 (TPA) ₂ O・Al ₂ O ₃・68.
It was OSiO ₂ 4.8H ₂ O. Further, this crystalline silica was calcined in air at 550° C. for 6 hours, and then ion exchanged overnight at room temperature using 5 ml of 1N ammonium nitrate solution per 1 g of the silica. Next, it was washed three times using 1.5% pure water and dried at 120°C for 6 hours.
It was further dried at 550°C for 6 hours to obtain a crystalline metal silicate adsorbent. Adsorbent Preparation Example 3 A solution A was prepared by dissolving 17.6 g of sulfuric acid and 26.3 g of tetranormal ammonium bromide in 250 ml of water. In addition, liquid B and liquid C similar to those in Adsorbent Preparation Example 1 were prepared. Gradually dropwise mix liquid A and liquid B into liquid C, then add 10.1 g of 50% sulfuric acid and stir to adjust the pH.
Prepared at 9.5. Subsequently, the obtained aqueous mixture was placed in an autoclave having a volume of 1, and a reaction was carried out for 20 hours at a temperature of 170° C. under autogenous pressure while stirring.
After cooling the reaction mixture, the product was washed 5 times with 1.5 g of water. The solid content was then separated by filtration and dried at 120° C. for 6 hours to obtain 50 g of crystalline metal silicate. The composition ratio (molar ratio) of this product is 6.5Na ₂ O・13.6(TPA) ₂ O・Al ₂ O ₃・
It was 62.0SiO ₂ ·1.6H ₂ O. Further, this crystalline silica was calcined in air at 550° C. for 6 hours, and then ion exchanged overnight at room temperature using 5 ml of 1N ammonium nitrate solution per 1 g of the silica. Next, it was washed three times using 1.5% pure water and dried at 120°C for 6 hours.
It was further dried at 550°C for 6 hours to obtain a crystalline metal silicate adsorbent. Adsorbent Preparation Example 4 72.85 g of high-purity silica was gradually added to a solution obtained by dissolving 11.18 g of sodium hydroxide in 320 ml of water, and the mixture was stirred for 1 hour to prepare Solution A. Also, add 32.4g of tetranormal ammonium bromide to 235g of water.
ml to prepare solution B. The aqueous mixture obtained by gradually dropping and mixing Solution B into Solution A was placed in a volume 1 autoclave, and the reaction was carried out at a temperature of 170° C. under autogenous pressure for 20 hours with stirring. After cooling the reaction mixture, it was filtered. Thereafter, washing and filtration were repeated using distilled water until the pH of the filtrate became 9 or less. Then, it was dried at 120° C. for 6 hours to obtain 48 g of crystalline metal silicate. The molar ratio (SiO ₂ /M ₂ O ₃ ) of this product was 3200. Furthermore, this crystalline metal silicate is
After firing at 550°C for 6 hours, the mixture was allowed to cool to obtain a crystalline metal silicate adsorbent. Adsorbent Preparation Example 5 167.2 g of tetramethyl orthosilicate was added to a solution consisting of 150 ml of water, 29.26 g of tetranormal ammonium bromide, and 50 ml of methanol, and solution A was prepared by stirring while heating at 80°C in a helium atmosphere for 1 hour. . In addition, Solution B was prepared by dissolving 10.12 g of sodium hydroxide in 345 ml of water. Then, it was dried at 120° C. for 6 hours to obtain 56 g of crystalline metal silicate. The molar ratio (SiO ₂ /M ₂ O ₃ ) of this product was over 10,000. Furthermore, this crystalline metal silicate is released into the air.
After firing at 550°C for 6 hours, the mixture was allowed to cool to obtain a crystalline metal silicate adsorbent. Example 1 200 mg of the crystalline metal silicate adsorbent obtained in Adsorbent Preparation Example 3 was placed in a test tube with a volume of 10 ml, and 0.1 M
2 ml of phosphate buffer (PH7.4) was added. Furthermore, 1,
After adding 30 mg of 2-butylene oxide and sealing the container, it was shaken and stirred at a predetermined temperature for 1 hour. Thereafter, the crystalline metal silicate and water were immediately separated by centrifugation, and the remaining butylene oxide in the water was quantified by gas chromatography. Furthermore, the aqueous phase after centrifugation was transferred to another Meyer flask. On the other hand, 2 ml of methanol was added to the precipitated crystalline metal silicate, stirred at 15°C for 10 minutes, and then centrifuged to collect the methanol phase.
The operation of adding methanol was repeated twice, and then the aqueous phase and methanol phase were mixed, and butylene glycol and butylene oxide in this water-methanol phase were determined by gas chromatography. The results are shown in Table 1.

[Table] Example 2 200 mg of the crystalline metal silicate obtained in Adsorbent Preparation Example 1 was placed in each 10 ml volume test tube, and 2 ml of the 0.1 molar buffer solution (PH 1.5 to 10) shown in Table 2 was added. added. Further, 20 mg of 1,2-butylene oxide was added, the container was tightly stoppered, and the mixture was shaken and stirred. Thereafter, the test tube was cooled in ice water and centrifuged at 4°C to separate the aqueous phase and crystalline metal silicate, and the amount of butylene oxide in the aqueous phase was determined by gas chromatography. Then, use a pipette to gently remove the aqueous phase.
Transferred to Meyer flask. Add 2 ml of methanol to the remaining crystalline metal silicate, seal it, and heat it at 15℃.
The mixture was shaken and stirred for 30 minutes. Thereafter, the crystalline metal silicate and methanol phase were separated by centrifugation. This methanol phase was gently removed using a pipette and mixed with the aqueous phase. Furthermore, methanol 2
ml was added, the same operation was performed, and butylene oxide and butylene glycol in the water-methanol phase were determined by gas chromatography. The results are shown in Table 2.

【table】

[Table] Example 3 250 mg of the crystalline metal silicate obtained in Adsorbent Preparation Example 3 was placed in each screw cap test tube with a volume of 10 ml, and 0.1 M phosphate buffer (PH7.4) was added to each test tube.
Added ml. Furthermore, after adding a certain amount of oxide shown in Table 3, the mixture was sealed with silicone rubber, and the mixture was shaken and stirred at 45°C for 30 minutes. Thereafter, the test tube was cooled in ice water and centrifuged at 4°C to separate the aqueous phase and crystalline metal silicate, and the amount of oxide in the aqueous phase was determined by gas chromatography. Then, use a pipette to gently remove the aqueous phase.
Transferred to Meyer flask. Add 5 ml of methanol to the remaining crystalline metal silicate, seal it, and heat it at 30℃.
Shake for 30 minutes. Thereafter, the crystalline metal silicate and methanol phase were separated by centrifugation.
This methanol phase was gently removed using a pipette and mixed with the aqueous phase. Additionally, 5 ml of methanol
was added, the same operation was performed, and the oxide and glycol in the water-methanol phase were determined by gas chromatography. The results are shown in Table 3.

[Table] Example 4 The adsorption and elution of butylene oxide was investigated in the same manner as in Example 2 except that the crystalline metal silicate obtained in Adsorbent Preparation Examples 2 and 3 was used. . Note that in this example, 0.1M phosphate buffer (PH7.4) was used. The results are shown in Table 4.

[Table] (However, in Table 4, the amount of adsorbed butylene oxide indicates the amount per 200 mg of adsorbent.) Example 5 250 mg of the crystalline metal silicate obtained in Adsorbent Preparation Example 2 was added to each screw cap with a volume of 10 ml. Add 0.1M phosphate buffer (PH7.4) to each test tube.
Added ml. The oxides shown in Table 5 were added to each of these test tubes at various concentrations, the tubes were sealed with silicone rubber, and the tubes were shaken and stirred at 45° C. for 30 minutes. Thereafter, the test tube was cooled in ice water and centrifuged at 4°C to separate the aqueous phase and crystalline metal silicate, and the oxides in the aqueous phase were determined by gas chromatography. The results are shown in Table 5.

[Table] Example 6 250 mg of the crystalline metal silicate obtained in Adsorbent Preparation Example 1 was placed in each 10 ml screw-cap test tube, and 5 ml of 0.1 M glycine buffer (PH9.0) and 20 mg of epoxy hexadecane were added thereto. After the addition, the mixture was sealed with silicone rubber and stirred with shaking at 60°C for 2 hours. Thereafter, the crystalline metal silicate was washed with 5 ml of tert-butyl methyl ether by centrifugation at 45°C, and the amount of unadsorbed epoxyhexadecane contained in the aqueous phase and the tert-butyl methyl ether phase was determined by gas chromatography. Its condensation, unadsorbed epoxyhexadecane 1.2
mg was detected. Furthermore, 5 ml of methanol was added to the crystalline metal silicate to elute the epoxy hexadecane, and as a result, 18.1 mg of epoxy hexadecane was recovered, and 0.1 mg of hexadecane 1,2-diol was recovered.
It was less than mg. Example 7 The same procedure as in Example 4 was carried out except that the crystalline metal silicate obtained in Adsorbent Preparation Examples 4 and 5 was used. The results are shown in Table 6.

【table】

[Table] (However, in Table 6, the amount of adsorbed butylene oxide indicates the amount per 200 mg of adsorbent.) Comparative Example 1 A volume of 200 mg of commercially available amorphous silica ("silica gel"; manufactured by Wako Pure Chemical Industries, Ltd.) Transfer to a 10ml screw cap test tube,
After adding 2 ml of 0.1M phosphate buffer (PH7.4),
20 mg of 1,2-butylene oxide was added, the mixture was tightly stoppered, and the mixture was stirred at 45°C for 30 minutes. Thereafter, the test tube was cooled in ice water and centrifuged at 4°C to separate the aqueous phase and silica gel. As a result of measuring the amount of butylene oxide in the aqueous phase, 19.2 mg of butylene oxide was detected, and no oxide was adsorbed. Comparative Example 2 Strong acidic ion exchange resin (trade name "Amberlite IR-120B"; manufactured by Rohm and Haas)
230 mg was washed with 1N hydrochloric acid and sodium hydroxide, and then washing was repeated using distilled water until the pH reached 7.5. This resin was placed in a 5 ml volumetric flask, and distilled water was added to bring the total volume to 5 ml.
Next, 20 mg of butylene oxide was added, a magnet was added, the container was tightly stoppered, and the mixture was stirred at 45° C. for 30 minutes. When the amount of butylene oxide in the water was then quantified, only a small amount of butylene oxide was detected, and 19.3 mg of butylene glycol was produced.

Claims (1)

[Scope of Claims] 1. A method for adsorbing and separating oxides from a solution containing oxides, the method comprising using crystalline silica and/or crystalline metal silicate as an adsorbent. 2 The crystalline metal _silicate has _the following formula _; M ₂ O ₃ . , varies depending on the value of X, etc.) and is composed of a trivalent metal oxide represented by
Adsorption and adsorption of oxides according to claim 1, which are one or more metal elements selected from the group consisting of La, Sc, Y, Cr, and Ti.
Separation method. 3. The crystalline metal silicate has a molar ratio of silicon oxide (SiO ₂ ) to trivalent metal (M ₂ O ₃ ) oxide (SiO ₂ /M ₂ O ₃ ) of 10 or more. A method for adsorbing and separating oxides according to scope 2.