JPH0649663B2 - Method for producing polyvalent alcohol - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a polyhydric alcohol obtained by hydration reaction of an epoxy compound (for example, ethylene glycol, propylene glycol, glycerin, etc., in one molecule). Compounds containing two or more hydroxyl groups will be collectively referred to, and the same shall apply hereinafter). More specifically, it relates to a method for producing a polyhydric alcohol by hydrating an epoxy compound in the presence of carbon dioxide with a nitrogen compound having a specific chemical structure as a catalyst.

Polyhydric alcohols represented by ethylene glycol, propylene glycol, glycerin and the like are compounds useful as raw materials for polyesters, antifreezes, polyether polyols, wetting agents, surfactants and the like.

(Prior Art) Conventionally, as a method for producing an alkylene glycol such as a polyhydric alcohol, particularly ethylene glycol or propylene glycol, an alkylene oxide such as ethylene oxide or propylene oxide, which is an epoxy compound, and water, under non-catalyst conditions, Alternatively, a method of carrying out a hydration reaction in the presence of a catalyst (usually a mineral acid such as sulfuric acid is used) is widely adopted industrially. (Chemical Engineering Association, edited by Chemical Process, pages 507-510, 585-589 (Tokyo Kagaku Dojin, published March 3, 1964), SAMiller, Ethylene and
its Industrial Derivatives, pp. 588-594 (Ernest Be
nn Ltd., 1969)) However, according to this method, a stoichiometric amount of 10 to the alkylene oxide is used in order to suppress by-products of multimers such as dialkylene glycol and trialkylene glycol as much as possible. It is necessary to use a large excess of about 30 mol times of water, and the target alkylene glycol can be obtained as a low-concentration aqueous solution. For this reason, a large amount of energy is consumed when concentrating, dehydrating, and rectifying into a final product, which is economically disadvantageous.

On the other hand, in recent years, in order to overcome the drawbacks of the above-mentioned production method, a method of subjecting an alkylene oxide and water in an amount close to a stoichiometric amount to a high-concentration hydration reaction in the presence of carbon dioxide has been actively studied. For example, a method using an alkali metal halide, an alkylamine hydrohalide or a tetraalkylammonium halide as a catalyst (JP-B-49-24448) or a method using a fourth phosphonium salt as a catalyst (JP-B-55-55-). No. 47617) is proposed.

(Problems to be Solved by the Invention) However, in Japanese Patent Publication No. Sho 49-24448, in addition to the above catalysts, in order to accelerate the reaction and reduce the by-products of multimers such as dialkylene glycol. Usually, it is necessary to use an alkali metal carbonate, hydrogen carbonate or hydroxide together.

On the other hand, in JP-B-55-47617, the catalyst performance is not sufficient, it is necessary to use a considerably large amount of the catalyst, and the catalyst itself is considerably expensive. Moreover, a polymer such as dialkylene glycol is used. In addition to the above, alkylene carbonate which is a cyclic carbonic acid ester also has a problem that it is by-produced in a considerably large amount.

In addition, since many alkylamine hydrohalides, tetraalkylammonium halides and quaternary phosphonium salts have a problem in safety to living bodies,
From the viewpoint of safety, it is not preferable as a catalyst for producing a product such as propylene glycol which is also used as an additive for foods, pharmaceuticals, cosmetics and the like.

As described above, the conventionally known catalyst has a problem in at least one of the catalyst performance, the catalyst price, the safety to the living body, and the like, and therefore it is the current situation that it has not been put to practical use industrially.

(Means for Solving Problems) The inventors of the present invention have made diligent efforts to overcome the defects of the prior art.
As a result of repeated studies, the general formula (I) R¹R²R³N C (R^Four) (R^Five) C (R⁶) (R⁷) OH / X (I) (In the formula, R¹, R²And R³Is an aliphatic hydrocarbon group, alicyclic carbon
A hydrogenated group or an aromatic hydrocarbon group, and R^Four, R^Five, R⁶
And R⁷Is a hydrogen atom or an aliphatic hydrocarbon group,
X Is halogen ion, hydroxide ion, carbonate ion, carbonic acid
Hydrogen ion, phosphate ion, hydrogen phosphate ion, sulfate ion
ON, hydrogen sulfate ion, nitrate ion, perchlorate ion,
Boron tetrafluoride ion, carboxylate ion and sulfo
Represents an anion selected from the group consisting of
The nitrogen compound represented by
That is, the present invention has been completed and the present invention has been completed.
It

That is, two epoxy compounds having 2 to 3 carbon atoms and water are used.
Homogeneous hydration in the presence of carbon oxide to give polyvalent alcohol
In the method for producing¹R²R³N C (R^Four) (R^Five) C (R⁶) (R⁷) OH / X (I) (In the formula, R¹, R²And R³Is an aliphatic hydrocarbon group, alicyclic carbon
A hydrogenated group or an aromatic hydrocarbon group, and R^Four, R^Five, R⁶
And R⁷Is a hydrogen atom or an aliphatic hydrocarbon group,
X Is halogen ion, hydroxide ion, carbonate ion, carbonic acid
Hydrogen ion, phosphate ion, hydrogen phosphate ion, sulfate ion
ON, hydrogen sulfate ion, nitrate ion, perchlorate ion,
Boron tetrafluoride ion, carboxylate ion and sulfo
Represents an anion selected from the group consisting of
Is used as a catalyst.
The present invention provides a method for producing a polyhydric alcohol.

The epoxy compound used in the method of the present invention has 1
There is no particular limitation as long as it is a compound having three or more oxygen-containing three-membered ring skeletons.

Specific examples of these epoxy compounds include ethylene oxide, propylene oxide (also known as 1,2-epoxypropane), 1,2-butylene oxide (also known as 1,2-epoxybutane), and 2,3-butylene oxide (also known as 2). , 3-Epoxybutane), isobutylene oxide (also known as 1,2-epoxyisobutane), 1,2-epoxypentane, 1,2-epoxyhexane, 1,2-epoxyoctane, 2,3-epoxyoctane, 3,4 -Epoxy octane, 1,2-epoxy decane, 1,2-epoxy dodecane, 1,2-epoxy tetradecane, 1,2-epoxy hexadecane, 1,2-epoxy octadecane, 1,2-epoxy eicosane, etc. -Or long-chain alkylene oxides, monoepoxy compounds of diene compounds such as 1,3-butadiene monooxide (also known as 1,3-butadiene monoepoxide), 1,3-butene Diepoxy compounds of such diene compounds diene oxides (also known as 1,3-butadiene diepoxide), cyclohexene oxide (also known as 1,2-epoxy cyclohexane), 1-methyl cyclohexene oxide (also known as 1,2-epoxy-1
Alicyclic epoxy compounds such as methylcyclohexane), 1,2-epoxycyclooctane, and 1,2-epoxycyclododecane, styrene oxide (also known as 1,2-epoxyethylbenzene), α-methylstyrene oxide (also known as 1,2-
Epoxy-2-phenylpropane), m-diisopropenylbenzene dioxide, p-diisopropenylbenzene dioxide, aromatic epoxy compounds such as 1,2-epoxy-3-phenylpropane, methyl glycidyl ether, ethyl glycidyl ether , Isopropyl glycidyl ether, n-propyl glycidyl ether, n-butyl glycidyl ether, sec-butyl glycidyl ether, 2-ethylhexyl glycidyl ether, stearyl glycidyl ether, allyl glycidyl ether,
Glycidyl ethers such as phenyl glycidyl ether, and other examples include epihalohydrin, glycidol and the like.

Among these epoxy compounds, ethylene oxide and propylene oxide are particularly preferable epoxy compounds.

Next, the water as the other reaction raw material is not particularly limited, tap water, ion-exchanged water, condensed water of steam, crude water-containing polyhydric alcohol in the polyhydric alcohol production apparatus by the method of the present invention Condensed water or the like that is recovered when concentrating or dehydrating can be arbitrarily used.

The amount of water used for the above-mentioned epoxy compound can be reduced to the stoichiometric amount, and may be less than the stoichiometric amount depending on the reaction mode, but from a practical point of view, at least slightly over the stoichiometric amount. It is preferable to use. Specifically, the amount of water is about 1.1 to 15 mole times, preferably 1.1 to 7 mole times, and most preferably 1.1 to 5 mole times per mole of the epoxy group (oxygen-containing three-membered ring skeleton) in the epoxy compound. .

Generally, when the other reaction conditions are the same, the larger the proportion of water used, the lower the by-product ratio of the multimer such as dialkylene glycol, but on the other hand, the concentration of the polyhydric alcohol produced by the hydration reaction increases. Using a large amount of water above the above upper limit is practically of little value as it causes the problem of lowering.

As carbon dioxide used in the method of the present invention, carbon dioxide gas,
Either liquefied carbonic acid or dry ice may be used.

The amount of carbon dioxide used can be varied within a wide range depending on the type and amount of the catalyst described later, the molar ratio of the epoxy compound and water, the selectivity and the yield of the desired polyhydric alcohol, and the like. Cannot be specified, but usually
It is about 0.0001 to 1 mol, preferably 0.001 to 1 mol, per 1 mol of the epoxy group in the epoxy compound.

When the other reaction conditions are the same, the selectivity and yield of the target polyhydric alcohol tend to improve as the amount of carbon dioxide used increases, but it is necessary to use above the upper limit value. There is no particular.

The catalyst used in the method of the present invention is represented by the above general formula (I).
Nitrogen compound, specifically, for example, (2-hydro
Xyethyl) trimethylammonium salt (R¹, R², R³= CH
₃, R^Four, R^Five, R⁶, R⁷= H), that is, choline chloride (X = C
l ), Choline bromide (X = Br ), Free choline base
(X = OH ), Choline bicarbonate (X = HCO₃ ),
Phosphorus phosphate (X = H₂PO_Four ), Choline sulfate (X
= HSO_Four ), Choline nitrate (X = NO₃ ), Choline
Chlorate (X = ClO_Four ), Choline boron tetrafluoride salt
(X = BF_Four ), Choline bitartrate (X = HOOCCH (O
H) -CH (OH) COO ), Choline acetate (X = CH₃COO ),
Choline citrateTypical examples are so-called choline compounds such as
In addition to, ethyl having a structure similar to choline compounds
(2-hydroxyethyl) dimethyl ammonium salt
(R¹, R²= CH₃, R³= C₂H_Five, R^Four, R^Five, R⁶, R⁷= H, anion
X Is the type, as long as it meets the definition above.
It doesn't matter. The same shall apply hereinafter), diethyl (2-hydroxy ether)
Chill) methyl ammonium salt (R¹= CH₃, R², R³= C₂H_Five,
R^Four, R^Five, R⁶, R⁷= H), triethyl (2-hydroxyethyl)
Lu) ammonium salt (R¹, R², R³= C₂H_Five, R^Four, R^Five, R⁶, R⁷=
H), (2-hydroxyethyl) isopropyldimethyl
Ammonium salt (R¹, R²= CH₃, R³= (CH₃)₂CH, R^Four, R^Five,
R⁶, R⁷= H), (2-hydroxyethyl) tripropyl
Ammonium salt (R¹, R², R³= C₃H₇, R^Four, R^Five, R⁶, R⁷=
H), tributyl (2-hydroxyethyl) ammonium
Mu salt (R¹, R², R³= C_FourH₉, R^Four, R^Five, R⁶, R⁷= H), (2-hi
Droxyethyl) dimethyloctyl ammonium salt
(R¹, R²= CH₃, R³= C₈H₁₇, R^Four, R^Five, R⁶, R⁷= H), Decyl
(2-hydroxyethyl) dimethyl ammonium salt
(R¹, R²= CH₃, R³= C_TenH_{twenty one}, R^Four, R^Five, R⁶, R⁷= H), Sech
(2-hydroxyethyl) dimethyl ammonium salt
(R¹, R²= CH₃, R³= C₁₆H₃₃, R^Four, R^Five, R⁶, R⁷= H), Ben
Zir (2-hydroxyethyl) dimethyl ammonium salt
(R¹, R²= CH₃, R³= C₆H_FiveCH₂, R^Four, R^Five, R⁶, R⁷= H), Ben
Zirdiethyl (2-hydroxyethyl) ammonium salt
(R¹, R²= C₂H_Five, R³= C₆H_FiveCH₂, R^Four, R^Five, R⁶, R⁷= H),
(2-hydroxyethyl) dimethylphenylammoniu
Mu salt (R¹, R²= CH₃, R³= C₆H_Five, R^Four, R^Five, R⁶, R⁷= H),
Chlohexyl (2-hydroxyethyl) dimethylammo
Nium salt (R¹, R²= CH₃, R³= C₆H₁₁, R^Four, R^Five, R⁶, R⁷=
H), (2-hydroxypropyl) trimethylammoni
Umm salt (R¹, R², R³= CH₃, R^Four, R^Five, R⁶= H, R⁷= CH₃), D
Cyl (2-hydroxypropyl) dimethyl ammonium
Salt (R¹, R²= CH₃, R³= C₂H_Five, R^Four, R^Five, R⁶= H, R⁷= C
H₃), Tributyl (2-hydroxypropyl) ammoni
Umm salt (R¹, R², R³= C_FourH₉, R^Four, R^Five, R⁶= H, R⁷= CH₃),
(2-hydroxybutyl) trimethylammonium salt
(R¹, R², R³= CH₃, R^Four, R^Five, R⁶= H, R⁷= C₂H_Five), Trier
Cyl (2-hydroxypentyl) ammonium salt (R¹, R
², R³= C₂H_Five, R^Four, R^Five, R⁶= H, R⁷= C₃H₇), Triethyl
(1-Methyl-2-hydroxyethyl) ammonium salt
(R¹, R², R³= C₂H_Five, R^Four= CH₃, R^Five, R⁶, R⁷= H), (2-
Hydroxypropyl) dimethyl phenyl ammonium salt
(R¹, R²= CH₃, R³= C₆H_Five, R^Four, R^Five, R⁶= H, R⁷= CH₃)etc
Can be used similarly to the choline compound.

Among the above catalysts, choline compounds, especially choline chloride, are industrially mass-produced for feed additives, which is extremely advantageous in terms of availability and cost, and is safe for living bodies. There is no problem at all.

These catalysts may be used alone, or,
You may use 2 or more types together. Furthermore, it is also possible to use it together with a conventionally known catalyst.

The amount of the catalyst used depends on the type and molecular weight of the catalyst and therefore cannot be specified uniformly, but is usually 0.01 to 20% by weight, preferably 0.05 to 1 with respect to the epoxy compound.
It is 0% by weight, most preferably 0.1 to 5% by weight.

When the amount of the catalyst used is less than the lower limit of the above range,
The effect is not sufficiently exhibited, and when it is used in a large amount exceeding the upper limit value, it is not economical, so both are not preferable.

The hydration reaction is usually carried out in a homogeneous liquid phase, and the reaction system may be a batch system, a semi-batch system or a continuous system. still,
The type of the reactor is not particularly limited as long as it is devised so that four members of the epoxy compound, water, carbon dioxide and the catalyst can be sufficiently contacted.

The reaction temperature varies depending on the type and amount of catalyst used, the type of epoxy compound, the composition of the reaction solution at the beginning of the reaction, etc.
0-300 ° C, preferably 50-250 ° C, most preferably 8
It is 0 to 200 ° C.

The reaction pressure is preferably such that the raw material epoxy compound maintains a liquid phase, and is usually 0 to 100 kg / cm ² G, preferably 3
˜70 kg / cm ² G, most preferably 5 to 50 kg / cm ² G.

After completion of the hydration reaction, water, carbon dioxide and catalyst present in the reaction product are removed by an arbitrary method, and the target polyhydric alcohol is purified by distillation or the like to obtain a highly pure product. be able to.

Since carbon dioxide and the catalyst are not substantially consumed, it is more economical to collect and reuse them.

(Function) Since the method of the present invention can significantly reduce the amount of water used in the hydration reaction, the reaction mass after the hydration reaction is obtained as a highly concentrated aqueous solution of polyhydric alcohol. In addition, the target polyhydric alcohol can be produced with high selectivity and high yield.

Another major feature is that the catalyst itself is inexpensive and highly safe for living organisms.

Therefore, it is extremely advantageous from the viewpoint of energy saving and resource saving, and has high industrial utility value.

(Examples) Hereinafter, the present invention will be described in detail with reference to Examples.

Example 1 A stainless steel autoclave having an internal volume of 200 m equipped with a stirrer, a thermometer and a pressure gauge was charged with 58 g (1 mol) of propylene oxide, 36 g (2 mol) of water and 1.16 g (2% by weight / propylene oxide) of choline chloride. After charging, carbon dioxide gas was injected at room temperature until the internal pressure of the autoclave reached 5 kg / cm ² G.

Then, the autoclave was placed in an electric furnace and stirred,
The internal temperature was raised to 160 ° C., and the reaction was carried out at that temperature for 1 hour. The internal pressure of the reactor increased to a maximum of 22 kg / cm ² G, then decreased as the hydration reaction proceeded, and the internal pressure at the end of the reaction was 17 kg / cm ² G.

After completion of the reaction, the autoclave was cooled to room temperature, a part of the reaction solution was sampled, and unreacted propylene oxide and the products propylene glycol, dipropylene glycol and tripropylene glycol were analyzed by an internal standard method using gas chromatography. Was quantitatively analyzed. The results are shown in the table.

No by-products such as propylene carbonate were found in the reaction solution.

Examples 2 to 16 The same autoclave as in Example 1 was used to carry out the hydration reaction of propylene oxide by varying the raw material charging amount, the catalyst type and charging amount, the reaction temperature, etc. as shown in the table. . The results are shown in the table.

Comparative Example 1 The hydration reaction of propylene oxide was carried out under the same conditions as in Example 1 except that carbon dioxide gas and a catalyst were not used at all.
The results are shown in the table.

Comparative Example 2 A propylene oxide hydration reaction was carried out under the same conditions as in Example 1 except that no catalyst was used (carbon dioxide gas was used). The results are shown in the table.

Example 17 The same autoclave as in Example 1 was charged with 44 g (1 mol) of ethylene oxide, 21.6 g (1.2 mol) of water and 1.76 g of choline chloride (4% by weight / ethylene oxide), and then the internal pressure of the autoclave was 40 kg / cm. Carbon dioxide was injected at room temperature until it reached ² G. Then, the temperature was raised to 160 ° C. with stirring, and the reaction was carried out at the temperature for 1.5 hours.

As a result of analyzing the reaction solution by the same method as in Example 1,
The conversion of ethylene oxide was 100%, the product was composed of 97.1% by weight of ethylene glycol and 2.9% by weight of diethylene glycol, and triethylene glycol and ethylene carbonate were not detected.

Example 18 Glycidol 37 was added to the same autoclave as in Example 1.
g (0.5 mol), water 18 g (1 mol) and choline chloride
After charging 0.74 g (2% by weight / glycidol), carbon dioxide gas was injected at room temperature until the internal pressure of the autoclave reached 10 kg / cm ² G. Then, the temperature was raised to 130 ° C. with stirring, the reaction was carried out at the temperature for 2 hours, and the reaction solution was analyzed. As a result, the conversion of glycidol was 100%, and the product was glycerin 91.2% by weight and diglycerin. It was 8.4 wt% and triglycerin 0.4 wt%.

Comparative Example 3 As a result of hydration reaction of glycidol under the same conditions as in Example 18 except that choline chloride and carbon dioxide were not used at all, the conversion rate of glycidol was 99.1%, and
The product was 62.5 wt% glycerin, 29.1 wt% diglycerin and 8.4 wt% triglycerin.

(Effects of the Invention) As described in detail in the above Examples and Comparative Examples, the method for producing a polyhydric alcohol of the present invention, in the coexistence of carbon dioxide, is a specific compound represented by a so-called choline compound such as choline chloride. By using a nitrogen compound as a catalyst, a high-concentration hydration reaction of an epoxy compound becomes possible, and moreover,
It is clear that the target polyhydric alcohols such as propylene glycol, ethylene glycol, and glycerin can be produced with high selectivity, high yield, and a sufficiently satisfactory reaction rate.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location C07B 61/00 300

Claims (5)

[Claims] 1. An epoxy compound having 2 to 3 carbon atoms and water.
Are allowed to undergo a homogeneous hydration reaction in the presence of carbon dioxide,
In the method for producing rucor, the general formula (I) R¹R²R³N C (R^Four) (R^Five) C (R⁶) (R⁷) OH / X (I) (In the formula, R¹, R²And R³Is an aliphatic hydrocarbon group, alicyclic carbon
A hydrogenated group or an aromatic hydrocarbon group, and R^Four, R^Five, R⁶
And R⁷Is a hydrogen atom or an aliphatic hydrocarbon group,
X Is halogen ion, hydroxide ion, carbonate ion, carbonic acid
Hydrogen ion, phosphate ion, hydrogen phosphate ion, sulfate ion
ON, hydrogen sulfate ion, nitrate ion, perchlorate ion,
Boron tetrafluoride ion, carboxylate ion and sulfo
Represents an anion selected from the group consisting of
Is used as a catalyst.
A method for producing a polyhydric alcohol. 2. The method for producing a polyhydric alcohol according to claim 1, wherein the catalyst is a choline compound. 3. The method for producing a polyhydric alcohol according to claim 2, wherein the choline compound is choline chloride. 4. The method for producing a polyhydric alcohol according to claim 2, wherein the choline compound is a free choline base. 5. The method for producing a polyhydric alcohol according to claim 2, wherein the choline compound is choline phosphate.