JP2003327426A - Hydrotalcite based hydrated metallic compound, production method thereof, catalyst for additional reaction of alkylene oxide obtained by firing the compound and method of evaluating the catalyst - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a catalyst which is excellent in a reaction rate and reaction selectivity in the additional reaction of alkylene oxide. <P>SOLUTION: Magnesium hydroxide or basic or neutral magnesium carbonate as a magnesium source and aluminum hydroxide as an aluminum source are brought into hydrothermal reaction at 120 to 300°C to obtain a hydrotalcite based hydrated metallic compound. The obtained hydrotalcite based hydrated metallic compound is fired at 400 to 800°C into a catalyst for the additional reaction of alkylene oxide to an active hydrogen atom-containing compound. Further, a storing base titration agent of 0.1 to 10 mol/L is dropped to a suspension obtained by adding a hydrotalcite based hydrated metallic compound to an acid aqueous solution prepared to a standard concentration of 0.001 to 0.1 mol/L so that the concentration of 0.05 to 2 wt.% can be obtained, and the pH of the suspension is measured by potentiometric titration with a glass electrode. In this case, the performance of the catalyst is evaluated from the consumption of hydroxide ions required to an inflection point of pH=10.3 from pH=7. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a hydrotalcite-based hydrated metal compound used as a precursor of an alkylene oxide addition reaction catalyst, a method for producing the same, and an alkylene oxide addition reaction catalyst obtained by firing the compound.
And a method for evaluating the performance of this catalyst.

[0002]

2. Description of the Related Art When a hydrotalcite-based hydrated metal compound is calcined and dehydrated, an alkylene oxide addition reaction catalyst is obtained. This catalyst is used as an addition reaction catalyst of alkylene oxide to higher alcohols.

A method for producing an alkylene oxide addition reaction catalyst using a hydrotalcite-based hydrated metal compound as a starting material has been proposed in Japanese Patent Laid-Open Nos. 2000-112272 and 20001-38212. However, there is no known study of the relationship between the surface properties of the hydrotalcite-based hydrated metal compound that is the precursor of this catalyst and the catalytic activity.

[0004]

DISCLOSURE OF THE INVENTION The inventor has found that the performance of an alkylene oxide addition reaction catalyst obtained by calcining a precursor hydrotalcite-based hydrated metal compound can be evaluated by potentiometric titration. Further, the inventors have found a method for producing a hydrotalcite-based hydrated metal compound which shows excellent results by the above-mentioned potentiometric titration and is therefore excellent as a precursor of an alkylene oxide addition reaction catalyst. Then, the inventor has developed a method for producing a catalyst from this hydrotalcite-based hydrated metal compound. The performance of this catalyst can be evaluated by potentiometric titration of a hydrotalcite-based hydrated metal compound, and the inventor has also developed a method for evaluating the catalyst performance.

As described above, the object of the present invention is to provide a novel hydrotalcite-based hydrated metal compound and a method for producing the same.
And an alkylene oxide addition reaction catalyst using the hydrated metal compound as a precursor, and a method for evaluating the catalyst.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The hydrotalcite-based hydrated metal compound of the present invention is represented by the formula (1) and has a specified concentration of 0.001 to 0.1 mol.
The hydrated metal compound was added to an acidic aqueous solution adjusted to 1 / L.
To the suspension added to a concentration of 0.05-2 wt%, 0.1
Hydroxide ion consumption required from pH = 7 to the inflection point of pH = 10.3 when potentiometric titration of the suspension pH with a glass electrode was performed by dropping ~ 10mol / L strong base titrant. Is 2 mmol or less per 1 g of the hydrotalcite-based hydrated metal compound. Mg _1-x Al _x (OH) ₂ (CO ₃ ) _{x / 2}・ mH ₂ O (0 <x <0.5, 0 <m <2) (1) Strong base titrants include sodium hydroxide and hydroxide. At least one member selected from the group consisting of potassium and ammonia and alkyl derivatives of ammonia is preferable.

The alkylene oxide addition reaction catalyst of the present invention is a hydrotalcite-based hydrated metal compound represented by the formula (1) in an acidic aqueous solution prepared at a specified concentration of 0.001 to 0.1 mol / L, 0.05 to 2 wt% of the hydrated metal compound
To the suspension added so as to have a concentration of 0.1 to 10 mol / L of a strong base titrant, when the pH of the suspension was potentiometrically titrated with a glass electrode, pH = 7 to pH = 10.3. The hydroxide ion consumption required up to the inflection point of is less than 2 mmol per 1 g of hydrotalcite-based hydrated metal compound, 400-80
It is obtained by firing at 0 ° C. and is represented by the formula (2). Mg _1-x Al _x (OH) ₂ (CO ₃ ) _{x / 2}・ mH ₂ O (0 <x <0.5, 0 <m <2) (1) Mg _1-x Al _x □ _{x / 2} O _{(2 + x) / 2} (where 0 <x <0.5, □ indicates a cation vacancy) (2) The strong base titrant is a group consisting of sodium hydroxide, potassium hydroxide and ammonia or an alkyl derivative of ammonia. At least one of is preferable. This alkylene oxide addition reaction catalyst is effective as an alkylene oxide addition reaction catalyst to an active hydrogen atom-containing compound such as a higher alcohol.

The hydrotalcite-based hydrated metal compound of the present invention uses, for example, at least one solid raw material of magnesium hydroxide, basic or neutral magnesium carbonate, and aluminum hydroxide, and the balance magnesium source or Aqueous slurry containing soluble magnesium salt or aluminum salt as the aluminum source, 120 ℃ or more 3
It is manufactured by hydrothermal reaction at 00 ° C or lower.

In the method for evaluating the addition reaction catalyst of alkylene oxide of the present invention, the hydrotalcite-based hydrated metal compound before calcination is added to an acidic aqueous solution prepared to a prescribed concentration of 0.001 to 0.1 mol / L in an amount of 0.05 to 2 wt%. To the suspension added to the concentration of 0.1 to 10 mol / L of a strong base titrant, the pH of the suspension is measured with a glass electrode and potentiometric titration is performed. Hydroxide ion consumption up to the inflection point of = 10.3 is 1 g of hydrotalcite-based hydrated metal compound
Therefore, when it is 2 mmol or less, the reaction rate and the reaction selectivity are good, and when the hydroxide ion consumption is more than 2 mmol, the reaction rate and the reaction selectivity are poor. (However, the hydrotalcite-based hydrated metal compound is represented by the formula (1),
The alkylene oxide addition reaction catalyst is 400-800
It is calcined at ° C and is represented by the formula (2), and the catalyst is a catalyst for the addition reaction of alkylene oxide to an active hydrogen atom-containing compound. The strong base titrators include sodium hydroxide, potassium hydroxide and ammonia. At least one member selected from the group consisting of alkyl derivatives of ammonia is preferable. Mg _1-x Al _x (OH) ₂ (CO ₃ ) _{x / 2}・ mH ₂ O (0 <x <0.5, 0 <m <2) (1) Mg _1-x Al _x □ _{x / 2} O _{(2 + x) / 2} (where 0 <x <0.5, □ indicates cation vacancies) (2)

[0010]

As shown in FIGS. 4 and 5, the catalytic performance of the alkylene oxide addition reaction catalyst can be evaluated by potentiometric titration of the precursor hydrotalcite-based hydrated metal compound. In other words, if the hydroxide ion consumption measured under the predetermined conditions by the potentiometric titration of the hydrotalcite-based hydrated metal compound is 2 mmol / [g hydrotalcite-based hydrated metal compound] or less, good catalytic performance is obtained. When the hydroxide ion consumption exceeds 2 mmol / [g hydrotalcite-based hydrated metal compound], good catalytic performance cannot be obtained. As described above, the properties of the hydrotalcite-based hydrated metal compound are hydroxide ion consumption measured under the conditions of claim 1 when viewed from the side of the alkylene oxide addition reaction catalyst, which is the main use thereof. Quantity
2 mmol / [g hydrotalcite-based hydrated metal compound] Varies depending on whether it is less than or equal to The hydrotalcite-based hydrated metal compound of the present invention provides excellent reaction rate and reaction selectivity when used as, for example, an alkylene oxide addition reaction catalyst.

In order to convert the hydrotalcite-based hydrated metal compound of the present invention into an addition reaction catalyst of alkylene oxide, it may be calcined, for example, at 400 to 800 ° C. The calcining atmosphere may be an inert atmosphere or a vacuum. preferable. 400-800
By calcining at ℃, the hydrotalcite-based hydrated metal compound is dehydrated and decarboxylated while maintaining the layered structure, and becomes an alkylene oxide addition reaction catalyst. Using this catalyst, high reaction rate and high reaction selectivity can be obtained. Is obtained.

In the method for evaluating an alkylene oxide addition reaction catalyst of the present invention, the hydrotalcite-based hydrated metal compound before firing is subjected to potentiometric titration under predetermined conditions to predict the performance of the alkylene oxide addition reaction catalyst. Therefore, it is effective for quality control and evaluation during the production of the alkylene oxide addition reaction catalyst.

[0013]

【Example】

[0014]

[Preparation of hydrotalcite-based hydrated metal compound and addition reaction catalyst] Preparation of hydrotalcite-based hydrated metal compounds and the obtained hydrotalcite-based hydrated metal will be described below as Examples 1 to 7. The alkylene oxide addition reaction catalyst obtained by firing the compound is shown. The hydrotalcite-based hydrated metal compound is prepared by a hydrothermal reaction, and a solid raw material that is moderately soluble at the reaction temperature is used as the raw material magnesium source and aluminum source. Both the magnesium source and the aluminum source are preferably solid raw materials having appropriate solubility, but only one may be added as a solid raw material and the other may be added as a soluble salt. As Comparative Examples 1 to 4, examples in which the hydrothermal reaction temperature is the same and both the magnesium source and the aluminum source are soluble salts are shown.

[0015]

EXAMPLE 1 Magnesium hydroxide [Mg (OH) _2] powder 56 g, basic magnesium carbonate _{[Mg 5 (CO 3) 4} (OH) 2 · 4H 2 O] powder 60
and 54 g of aluminum hydroxide [Al (OH) ₃ ] powder were added to pure water to prepare a mixed slurry of 1.5 L (Mg / Al charging molar ratio: 2.3, CO ₂ / Al charging molar ratio: 0.75) . This was placed in a 2 L autoclave, heated to 180 ° C., and hydrothermally reacted for 5 hours while stirring. After completion of the reaction, the slurry is cooled to room temperature, suction filtered and washed with water, dried at 120 ° C. for 24 hours, and then pulverized to obtain a hydrotalcite-based hydrated metal compound (A
-1) was obtained. The hydrotalcite-calcined metal oxide catalyst (B-1) was obtained by calcining the obtained hydrotalcite-based hydrated metal compound at 500 ° C. for 3 hours in a nitrogen atmosphere.

When the hydrothermal reaction temperature is set to 100 ° C., a solid unreacted residue remains, and the hydrothermal reaction temperature of 120
A solid residue does not occur at 0 ° C., and the entire amount of the input raw material can be converted to the hydrotalcite-based hydrated metal compound. Therefore, the hydrothermal reaction temperature is preferably 120 ° C. or higher. The hydrothermal reaction temperature is 30
When the temperature exceeds 0 ° C., the hydrothermal reaction temperature is preferably 120 ° C. to 300 ° C., particularly preferably 120 ° C. to 250 ° C., considering that the pressure during the reaction becomes too high.

The composition of magnesium hydroxide, basic magnesium carbonate, or aluminum hydroxide added may be subtly different due to crystallization water or variations in the ratio of carbonic acid groups to hydroxyl groups. Is not important. Further, the composition of magnesium hydroxide, basic magnesium carbonate, or aluminum hydroxide may be replaced with, for example, a metal component, a hydroxyl group or a carbonate group at a ratio of 10 mol% or less. Hydrothermal reaction in the autoclave, magnesium source (magnesium hydroxide, basic magnesium carbonate, neutral magnesium carbonate) and aluminum source (aluminum hydroxide) is gradually eluted by hydrothermal reaction,
It is considered to be converted to a hydrotalcite-based hydrated metal compound.

The hydrothermal reaction time in the autoclave is 1 to
About 24 hours is preferable, and the concentration of the slurry is the above-mentioned concentration (1.5 mol / in terms of hydrotalcite-based hydrated metal compound).
L) may be changed in the range of 1/5 to 5 times, especially 1/3
It may be changed in the range of about 3 times. As described below,
In order to obtain the desired hydrotalcite-based hydrated metal compound, it is necessary to use at least one solid raw material for the magnesium source and the aluminum source. Particularly, the aluminum source should be almost all solid (90 mol% or more) or the magnesium source. Is preferably (90 mol% or more) entirely solid. Although no specific result is shown, when magnesite (MgCO ₃ ) is used as the magnesium source, a solid residue remains during the hydrothermal reaction, and boehmite (AlOO) is used as the aluminum source.
A solid residue remained with H). This is probably because magnesite and boehmite are stable under hydrothermal conditions and have low solubility.

The firing temperature is, for example, 400 to 800 ° C., and the firing atmosphere may be an inert atmosphere (except CO ₂ ) such as Ar in addition to nitrogen, or in a vacuum. Any atmosphere may be used as long as it can be dehydrated and decarboxylated without destroying the layered structure of the compound and converted into an addition reaction catalyst of alkylene oxide. The catalyst is a solid solution of rock salt type magnesium oxide and aluminum oxide. If the firing temperature exceeds 800 ° C, conversion into spinel occurs, so the firing temperature is set to 400 to 800 ° C.

[0020]

Example 2 66 g of magnesium hydroxide powder, neutral carbonate
Gnesium [MgCO₃・ 3H₂56 g of O powder and aluminum hydroxide
Using 60 g of um powder as a solid raw material (Mg / Al charge molar ratio: 2.
0, CO ₂/ Al charge molar ratio: 0.53), carried out in an autoclave
Hydrothermal reaction was carried out at 180 ° C. for 5 hours in the same manner as in Example 1. Other reaction conditions
Hydrotalcite-based hydration was carried out in the same manner as in Example 1.
A metal compound (A-2) and a calcined metal oxide catalyst (B-2) were obtained.

[0021]

Example 3 Magnesium hydroxide powder 16 g, basic magnesium carbonate powder 95 g, and aluminum hydroxide powder 59 g
Was used as a solid raw material (Mg / Al charge molar ratio: 1.7, CO ₂ / Al
Charged molar ratio: 1.07). Other than this, the same operation as in Example 1 was carried out to obtain the hydrotalcite-based hydrated metal compound (A-3).
And a calcined metal oxide catalyst (B-3) was obtained.

[0022]

[Example 4] The hydrotalcite-based hydrated metal compound (A-4) and the calcined metal oxide catalyst (B) were prepared in the same manner as in Example 1 except that the reaction temperature in the autoclave was 120 ° C. -4) was obtained. Even under these conditions, the total amount of raw materials was converted to hydrotalcite-based hydrated metal compounds.

[0023]

[Example 5] The hydrotalcite-based hydrated metal compound (A-5) and the calcined metal oxide catalyst (B) were prepared in the same manner as in Example 1 except that the reaction temperature in the autoclave was 240 ° C. -5) was obtained.

[0024]

[Example 6] Aluminum hydroxide [Al (OH) ₃ ] was stirred while stirring 1 L of a magnesium chloride solution having a concentration of 5.9 wt% in terms of MgO.
After adding 54 g of powder, pH = 1 with 25 wt% sodium hydroxide solution.
Keep it at 0 and 880 a 5 wt% sodium carbonate solution 880
mL was gradually added (Mg / Al charged molar ratio: 2.1, CO ₂ / Al charged molar ratio: 0.60). The same operation as in Example 1 was carried out on 1.5 L of this slurry to prepare a hydrotalcite-based hydrated metal compound (A
-6) and a calcined metal oxide catalyst (B-6) were obtained.

[0025]

Example 7 While stirring 1 L of a 3.9 wt% aluminum chloride solution calculated as Al ₂ O ₃ , 83 g of magnesium hydroxide powder was added, and then pH = 10 was maintained with a 25 wt% sodium hydroxide solution. 980 mL of 5 wt% concentration sodium carbonate solution was gradually added (Mg / Al charging molar ratio: 1.9, CO ₂ / Al charging molar ratio: 0.6
0). 1.5 L of this slurry was subjected to the same operations as in Example 1 to obtain a hydrotalcite-based hydrated metal compound (A-7) and a calcined metal oxide catalyst (B-7).

[0026]

[Comparative Example 1] 159 g of sodium aluminate having a concentration of 20.0 wt% in terms of Al ₂ O ₃ was dropped while stirring 1 L of a magnesium chloride solution having a concentration of 5.9 wt% in terms of MgO, and then a 25 wt% sodium hydroxide solution Then, 700 mL of a 5 wt% concentration sodium carbonate solution was gradually added to maintain pH = 10 (Mg / Al charging molar ratio: 2.5, CO ₂ / Al charging molar ratio: 0.53). The same operation as in Example 1 was performed on 1.5 L of the obtained white precipitate slurry,
A hydrotalcite-based hydrated metal compound (C-1) and a calcined metal oxide catalyst (D-1) were obtained.

[0027]

[Comparative Example 2] While stirring 1 L of a magnesium chloride solution having a concentration of 5.4 wt% as MgO, 191 g of sodium aluminate having a concentration of 20.0 wt% as Al ₂ O ₃ was dropped, and then a 25 wt% sodium hydroxide solution was added. Then, 1150 mL of a 5 wt% sodium carbonate solution was gradually added while maintaining pH = 10 (Mg / Al charging molar ratio: 1.9, CO ₂ / Al charging molar ratio: 0.70). The white precipitation slurry (1.5 L) thus obtained was subjected to the same operations as in Example 1 to obtain a hydrotalcite-based hydrated metal compound (C-2) and a calcined metal oxide catalyst (D-2).

[0028]

[Comparative Example 3] 5.7 wt% concentration in terms of MgO and 3.5 w in terms of Al ₂ O _3.
1% of t% magnesium chloride and aluminum chloride mixed solution
While stirring, pH = 10 with 25 wt% sodium hydroxide solution.
5wt% sodium carbonate solution 1400
mL was gradually added (Mg / Al charged molar ratio: 2.0, CO ₂ / Al charged molar ratio: 0.98). 1.5 L of the obtained white precipitate slurry was subjected to the same operations as in Example 1 to obtain a hydrotalcite-based hydrated metal compound (C-3) and a calcined metal oxide catalyst (D-3).

[0029]

[Comparative Example 4] 1 L of a mixed solution of magnesium chloride having a concentration of 5.7 wt% in terms of MgO and aluminum chloride having a concentration of 3.5 wt% in terms of Al 2 O 3 was stirred and stirred with a 25 wt% sodium hydroxide solution to obtain a p
Keep H = 10, 5wt% sodium carbonate solution
930 mL was gradually added (Mg / Al charge molar ratio: 2.0, CO2 / Al
Charged molar ratio: 0.65). Then, the same operation as in Example 1 was performed, except that 1.5 L of the obtained white precipitate slurry was aged at 40 ° C. for 5 hours with stirring, to obtain the hydrotalcite-based hydrated metal compound (C-4) and the calcined metal oxide. A catalyst (D-4) was obtained.

Hydrotalcite-based hydrated metal compound powders prepared in Examples and Comparative Examples (A-1 to A-7 and C-1 to C-4)
Was subjected to X-ray diffraction measurement. A peak pattern of hydrotalcite [Mg _1-x Al _x (OH) ₂ (CO ₃ ) _{x / 2}・ mH ₂ O] was confirmed for all samples, and almost all was converted to hydrotalcite-based hydrated metal compounds. It has been found.

Hydrotalcite-based hydrated metal compound powders prepared in Examples and Comparative Examples (A-1 to A-7 and C-1 to C-4)
The amounts of MgO, Al ₂ O ₃ and CO ₂ contained in were analyzed chemically. The results are shown in Table 1. In the composition formula (1) of the hydrotalcite-based hydrated metal compound, the carbonate content is about 1/2 of the Al content x.

[0032]

[Table 1] Hydrotalcite-based hydration Analysis composition Metal compound powder sample A-1 (Example 1) Mg _0.695 Al _0.305 (OH) ₂ (CO ₃ ) _0.163 · mH ₂ O A-2 (Example 2) Mg _0.661 Al _0.339 (OH) ₂ (CO ₃ ) _0.167・ mH ₂ O A-3 (Example 3) Mg _0.620 Al _0.380 (OH) ₂ (CO ₃ ) _0.158・ mH ₂ O A-4 (Example 4) Mg _0.699 Al _0.301 (OH) ₂ (CO ₃ ) _0.165・ mH ₂ O A-5 (Example 5) Mg _0.697 Al _0.303 (OH) ₂ (CO ₃ ) _0.164・ mH ₂ O A-6 (Example 6) Mg _0.674 Al _0.326 (OH) ₂ (CO ₃ ) _0.166・ mH ₂ O A-7 (Example 7) Mg _0.645 Al _0.355 (OH) ₂ (CO ₃ ) _0.170・ mH ₂ O C-1 (Comparative Example 1) Mg _0.697 Al _0.303 (OH) ₂ (CO ₃ ) _0.166・ mH ₂ O C-2 (Comparative Example 2) Mg _0.638 Al _0.362 (OH) ₂ (CO ₃ ) _0.162・ mH ₂ O C-3 (Comparative Example 3) _{mg 0.669 Al 0.331 (OH) 2} (CO 3) 0.176 · mH 2 O C-4 ( Comparative example _{4) mg 0.678 Al 0.322 (OH} ) 2 (CO 3) 0.170 · mH 2 O

[0033]

[Evaluation of hydrotalcite-based hydrated metal compound by potentiometric titration] Powder of hydrotalcite-based hydrated metal compound prepared in Examples and Comparative Examples (A-1 to A-7 and C-1 to C-4 )
0.5 g of each was added to 200 ml of a nitric acid aqueous solution adjusted to 0.015 mol / L, and stirred for 10 minutes. While measuring the pH of this suspension after stirring with a glass electrode, the pH of the 1 mol / L sodium hydroxide aqueous solution was 0.1 ml / min using an automatic titrator (AT-400 manufactured by Kyoto Electronics Manufacturing Co., Ltd.). Titration curve was obtained by dropping until reaching about 11. During the titration, the suspension should be kept in a constant temperature bath.
The temperature was maintained at 25 ° C, and bubbling with nitrogen gas was performed.
The obtained titration curves are shown in FIGS.

Under the above-mentioned measurement conditions, even if the specified concentration of the acidic aqueous solution was changed in the range of 0.001 to 0.1 mol / L, the result of potentiometric titration was the same, and the hydrotalcite hydrated metal in the acidic aqueous solution was the same. Even if the concentration of the compound was changed in the range of 0.05 to 2 wt%, the result of potentiometric titration was the same. In addition to sodium hydroxide, for example, potassium hydroxide, ammonia, or an alkyl derivative of ammonia such as monomethyl to trimethyl may be used as the strong base titrant. Even if the concentration of the strong base titrant is changed in the range of 0.1 to 10 mol / L, the influence on the result of potentiometric titration is small. And since the hydroxide ion consumption from pH = 7 is a problem, the influence of PH before the start of titration can be removed, an inflection point appears in the titration curve at pH = 10.3, pH = 7 to pH = The hydroxide ion consumption up to 10.3 represents the surface properties of hydrotalcite-based hydrated metal compounds.

From the titration curve obtained, pH = 7 and pH = 10.3
The amount of 1 mol / L sodium hydroxide solution added dropwise at the inflection point was read, and the hydroxide ion consumption (mmol / 0.5 g hydrotalcite) required from pH = 7 to pH = 10.3 was calculated. The results are shown in Table 2.

[0036]

[Table 2] Hydrotalcite 1 mol / L sodium hydroxide Hydroxide powder sample Ion consumption PH = from pH = 7 to pH = 10.3 7 pH = 10.3 (mmol / 0.5g hydrotalcite) A-1 (Example 1) 1.25 2.06 0.81 A-2 (Example 2) 1.51 2.39 0.88 A-3 (Example 3) 1.56 2.51 0.95 A-4 ( Example 4) 0.96 1.95 0.99 A-5 (Example 5) 1.16 2.08 0.92 A-6 (Example 6) 1.36 2.26 0.90 A-7 (Example 7) 1.46 2.42 0.96 C-1 (Comparative Example 1) 1.36 2.48 1.12 C-2 (Comparative Example 2) 1.32 2.58 1.26 C-3 (Comparative Example 3) 1.36 2.54 1.18 C-4 (Comparative Example 4) 0.84 2.06 1.22

[0037]

[Synthesis of alkylene oxide adduct] Lauryl alcohol 18 as a compound containing active hydrogen in a 3 L autoclave
8 g (1 mol) and hydrotalcite calcined metal oxide catalysts prepared in Examples and Comparative Examples (B-1 to B-7 and D-1 to D-4) 1.88
After charging g and replacing with nitrogen, the temperature was raised to 150 ° C. with stirring. After the temperature was raised, 264 g (3 mol) of ethylene oxide was gradually introduced, and when the pressure reduction was completed after 2 hours, the mixture was aged at the same temperature for 1 hour and reacted for a total of 3 hours.
Then, the mixture was cooled to room temperature, and the calcined metal oxide catalyst remaining in the crude product was separated by filtration to obtain a purified product. By gas chromatography, the distribution of the degree of addition polymerization of ethylene oxide was measured, and the reaction rate and reaction selectivity were determined by the following (Formula 3) and (Formula 4).
Calculated from The results are shown in Table 3. Reaction rate (%) = (total stoichiometry-unreacted chemical stoichiometry where the number of moles of ethylene oxide added is 0) / (total stoichiometry) × 100 (Equation 3) Reaction selectivity (%) = (moles of ethylene oxide added) Reaction product stoichiometry in which the number is n-1 to n + 1) / (total stoichiometry) × 100 (Formula 4) Note that n represents the number of moles of added ethylene oxide charged with respect to 1 mole of lauryl alcohol, Here it is 3.

[0038]

[Table 3] Ratio of number of moles of ethylene oxide added (%) Reaction rate Reaction (%) Selectivity 0 1 2 3 4 5 6 7 8 9 (%) n-1 n n + 1 B-1 (Example 1) 5 7 17 22 19 13 8 5 3 1 95 58 B-2 (Example 2) B-3 (Example 3) B-4 (Example 4) 7 9 16 20 18 12 8 5 3 2 93 54 B- 5 (Example 5) B-6 (Example 6) 6 9 16 21 19 14 9 3 2 1 94 56 B-7 (Example 7) D-1 (Comparative Example 1) 11 12 15 17 16 13 10 4 2 ― 89 48 D-2 (Comparative example 2) 13 12 12 13 12 11 9 7 6 5 87 37 D-3 (Comparative example 3) 12 13 15 16 15 13 9 5 2 ― 88 46 D-4 (Comparative example 4) 13 11 12 13 13 12 10 7 5 4 87 38

[0039]

[Correlation between potentiometric titration data and reaction rate and reaction selectivity] Hydroxide ion consumption (mmol) from pH = 7 to pH = 10.3 calculated from potentiometric curve and reaction rate and reaction selection in ethylene oxide addition reaction The correlation with sex is shown in FIGS. 4 and 5. It was found from FIGS. 4 and 5 that there is a good correlation, and it was found that the catalyst performance can be easily evaluated by the potentiometric titration method. Further, as in the example, using solid powder consisting of magnesium hydroxide, basic magnesium carbonate, neutral magnesium carbonate, aluminum hydroxide as a starting material, if hydrothermally synthesized at 120 to 300 ° C., the reaction rate and reaction It was revealed that a highly selective catalyst precursor was obtained. Then, by calcining this at 400 to 800 ° C., a catalyst having a high reaction rate and a high reaction selectivity can be obtained.

In the examples, the hydrotalcite-based hydrated metal compound was used as the precursor of the alkylene oxide addition reaction catalyst, but the application of the hydrotalcite-based hydrated metal compound is not limited to this. For example, it can be used as an adsorbent for anions such as chlorine ions in processing polyvinyl chloride. Although a method for producing a hydrotalcite-based hydrated metal compound using a hydrothermal reaction was shown in the examples, a hydrotalcite-based hydrated metal compound suitable as a catalyst precursor is a hydrotalcite-based hydrated metal compound produced by hydrothermal synthesis. It is not limited to.

[Brief description of drawings]

FIG. 1 is a characteristic diagram showing a potentiometric titration curve for hydrotalcite-based hydrated metal compounds of Examples.

FIG. 2 is a characteristic diagram showing a potentiometric titration curve for hydrotalcite-based hydrated metal compounds of Examples.

FIG. 3 is a characteristic diagram showing a potentiometric titration curve for hydrotalcite-based hydrated metal compounds of Examples.

FIG. 4 is a characteristic diagram showing the relationship between hydroxide ion consumption during potentiometric titration of hydrotalcite-based hydrated metal compounds and the reaction rate of the addition reaction of ethylene oxide with lauryl alcohol.

FIG. 5 is a characteristic diagram showing the relationship between hydroxide ion consumption during potentiometric titration of hydrotalcite-based hydrated metal compounds and reaction selectivity of addition reaction of ethylene oxide to lauryl alcohol.

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 4G069 AA02 AA08 BB06A BB06B                       BC10A BC10B BC16A BC16B                       CB25 EA01Y FB04 FB06                       FB34 FB77                 4G076 AA10 AA16 AA18 AA19 AA21                       AB06 AB09 AB10 BA12 BD02                       DA01                 4H006 AA02 AC41 AC43 GP01 GP10

Claims (5)

[Claims] 1. A hydrotalcite-based hydrated metal compound represented by the formula (1), wherein the hydrated metal compound is added to an acidic aqueous solution prepared at a specified concentration of 0.001 to 0.1 mol / L in an amount of 0.05 to To the suspension added to have a concentration of 2 wt%, 0.1 to 10 mol / L of a strong base titrant was added dropwise, and the pH of the suspension was measured potentiometrically with a glass electrode. Hydroxide ion consumption up to the inflection point of = 10.3 is 1 g of hydrotalcite-based hydrated metal compound
A hydrotalcite-based hydrated metal compound having a content of 2 mmol or less. Mg _1-x Al _x (OH) ₂ (CO3) _{x / 2}・ mH ₂ O (0 <x <0.5, 0 <m <2) (1) 2. An addition reaction catalyst of an alkylene oxide represented by the formula (2) obtained by calcining the hydrotalcite-based hydrated metal compound according to claim 1 at 400 to 800 ° C. Mg _1-x Al _x □ _{x / 2} O _{(2 + x) / 2} (where 0 <x <0.5, □ indicates cation vacancies) (2) 3. An aqueous solution in which at least one solid raw material of magnesium hydroxide, basic or neutral magnesium carbonate, and aluminum hydroxide is used, and the balance magnesium source or aluminum source is a soluble magnesium salt or aluminum salt. A method for producing a hydrotalcite-based hydrated metal compound, comprising subjecting the slurry to hydrothermal reaction at 120 ° C. or higher and 300 ° C. or lower to obtain the compound of claim 1. 4. The alkylene oxide addition reaction catalyst according to claim 2, wherein the alkylene oxide addition reaction catalyst is an alkylene oxide addition reaction catalyst to an active hydrogen atom-containing compound. 5. A suspension prepared by adding a hydrotalcite-based hydrated metal compound before calcination to an acidic aqueous solution prepared to a prescribed concentration of 0.001 to 0.1 mol / L so as to have a concentration of 0.05 to 2 wt%. , 0.1 to 10 mol / L strong base titrator was added dropwise, the pH of the suspension was measured with a glass electrode and potentiometric titration was performed, and the hydroxylation required from the inflection point of pH = 7 to pH = 10.3 The reaction rate and reaction selectivity are good when the product ion consumption is 1 g of hydrotalcite-based hydrated metal compound and is 2 mmol or less, and the reaction rate and the reaction are when the hydroxide ion consumption is more than 2 mmol. A method for evaluating an alkylene oxide addition reaction catalyst, which has poor selectivity. (However, the hydrotalcite-based hydrated metal compound is represented by the formula (1), the addition reaction catalyst of the alkylene oxide is represented by the formula (2) by firing this at 400 ~ 800 ℃, the catalyst is active hydrogen Mg _1-x Al _x (OH) ₂ (CO ₃ ) _{x / 2}・ mH ₂ O (0 <x <0.5, 0 <m <2) (1 which is a catalyst for the addition reaction of alkylene oxide to atom-containing compounds) ) Mg _1-x Al _x □ _{x / 2} O _{(2 + x) / 2} (where 0 <x <0.5, □ indicates a cation vacancy) (2)