JP2008150331A - Method for producing alkylene oxide adduct - Google Patents

Abstract

【Task】
Provided is a method for producing an excellent alkylene oxide adduct using a higher alcohol and an alkylene oxide and having few polyalkylene glycol side reaction products.
[Solution]
In the method for producing an alkylene oxide adduct by reacting a higher alcohol and an alkylene oxide, the carbonyl value of the higher alcohol is 60 ppm or less, and the alkylene oxide is brought into contact with a reaction raw material mixture containing the higher alcohol and a catalyst. A method for producing an alkylene oxide adduct, wherein the water concentration in the reaction raw material mixture is less than 200 ppm.
[Selection figure] None

Description

  The present invention relates to a method for producing an excellent alkylene oxide adduct containing a small amount of side reaction products such as polyethylene glycol from a higher alcohol and an alkylene oxide.

  Conventionally, alkylene oxide adducts obtained by reacting alkylene oxide with higher alcohols, esters, hydrogenated castor oil, etc. are important as industrial nonionic components or nonionic components in cosmetic detergents and detergents. It is a compound used in a wide range of fields such as emulsifiers and dispersants, and as an intermediate for solvents, polyurethane resin raw materials and chemicals.

  Alkylene oxide adducts are usually produced by addition reaction of alkylene oxides with higher alcohols, esters, hydrogenated castor oil, etc. in the presence of a hydrous alkaline catalyst. In such a method using a hydrous alkaline catalyst, in order to avoid the formation of a by-product due to the reaction between water derived from the catalyst or raw material and alkylene oxide, the addition reaction is performed after removing water in the system as much as possible. However, it is known that when the addition reaction is performed in a state where the water concentration is extremely low, the side reaction product has a higher molecular weight and lowers the liquid stability.

Moreover, the reaction product containing the alkylene oxide adduct produced using the hydrous alkaline catalyst usually contains a polyalkylene glycol such as polyethylene glycol as a by-product. Therefore, there is a problem that the mixture obtained by adding water to this reaction product becomes cloudy due to changes over time, and it is required to separate and remove this by-product prior to use, but the known separation and removal method is sufficient. The purpose cannot be achieved, and a large amount of equipment is required industrially. Therefore, in order to produce an alkylene oxide adduct with few side reaction products and excellent liquid stability, the water concentration in the reaction liquid phase after addition of the aqueous alkaline catalyst solution is adjusted to 0.02 to 0.15% by weight. Then, a method of performing an addition reaction has been proposed (Japanese Patent Laid-Open No. 2000-344702). Specifically, in this method, hydrogenated castor oil is subjected to addition reaction of ethylene oxide to produce an alkylene oxide adduct, and the amount of side reaction product (polyethylene glycol) having a molecular weight of 2000 or more is reduced, but the molecular weight is 2000 or less. Inhibition of the formation of by-products of relatively low molecular weight is not always sufficient.
JP 2000-344702 A

  The present invention uses a higher alcohol and an alkylene oxide as raw materials to produce a polyalkylene glycol such as polyethylene glycol, for example, an excellent alkylene oxide adduct with a relatively high molecular weight polyalkylene glycol side reaction product having a molecular weight of about 1000 or more. Provide a way to do it.

  As a result of intensive studies on a method for reducing the production of side reaction products in the production of an alkylene oxide adduct using a higher alcohol as a raw material, the present inventors have affected the production of the side reaction product by the carbonyl value of the reaction raw material alcohol. It was found that by-products increased when the carbonyl number was high. And by adjusting the carbonyl value of the carbonyl group-containing compound such as aldehyde contained in the raw material higher alcohol to a predetermined value or less, even if the addition reaction is carried out in a state where the water concentration is extremely low using a hydrous alkali catalyst, it is a side reaction. The inventors have found that the production of products can be suppressed, and reached the present invention.

  That is, the gist of the present invention is a process for producing an alkylene oxide adduct by reacting a higher alcohol with an alkylene oxide, wherein the carbonyl value of the higher alcohol is 60 ppm or less, and a reaction raw material mixture containing the higher alcohol and a catalyst. The alkylene oxide adduct is characterized in that the water concentration in the reaction raw material mixture when the alkylene oxide is contacted is less than 200 ppm.

  According to the method of the present invention, for example, an excellent alkylene oxide adduct with a small amount of a side reaction product of a relatively high molecular weight polyalkylene glycol having a molecular weight of 1000 or more can be produced. Since the content of the side reaction product is small, it can be used as it is as a nonionic surfactant and is extremely useful.

Embodiments of the present invention will be described below, but these are representative aspects and do not limit the present invention.
In the present specification, ppm means ppm by mass unless otherwise specified.

  The present invention relates to a method for producing an alkylene oxide adduct by addition reaction of a higher alcohol and an alkylene oxide. The carbonyl value of the higher alcohol is 60 ppm or less, and the alkylene oxide is brought into contact with a reaction raw material mixture containing the higher alcohol and a catalyst. It is a method which makes it essential that the moisture concentration in the reaction raw material mixture at the time of making it be less than 200 ppm.

  The higher alcohol used as a raw material in the method of the present invention is a linear or branched saturated alcohol or unsaturated alcohol having 5 to 38 carbon atoms. Among these, as the higher alcohol, usually a saturated or unsaturated alcohol having 8 to 20 carbon atoms, preferably 11 to 16 carbon atoms, more preferably 12 to 15 carbon atoms is used, and these may be used alone or in combination of two or more. It can also be used as a mixture of Specifically, 1-octanol, 1-decanol, 1-dodecanol, 1-tridecanol, 1-tetradecanol, 1-pentadecanol, 1-hexadecanol, 1-octadecanol, 2-ethyl-1- Examples include linear or branched aliphatic saturated alcohols such as hexanol, among which linear aliphatic saturated alcohols such as 1-dodecanol, 1-tridecanol, 1-tetradecanol, 1-pentadecanol, 1-hexadecanol and the like. 1-dodecanol and 1-tridecanol are particularly preferable. As these higher alcohols, commercially available products can be used because they are easily available. For example, trade names “Dovanol”, “Diadol” (all manufactured by Mitsubishi Chemical Corporation), “Neodol” (trade name: A series of products marketed by Shell Chemicals Co., Ltd.).

  Examples of the alkylene oxide used in the method of the present invention include alkylene oxides having 2 to 4 carbon atoms such as ethylene oxide, propylene oxide, and butylene oxide. Usually, ethylene oxide and propylene oxide are used, preferably ethylene oxide. Is used. As the alkylene oxide, it is usually preferable to use one having a purity of 99% or more.

  The alkylene oxide adduct of higher alcohol obtained by the production method of the present invention is represented by the following general formula.

[Chemical 1]
RO (AO) nH
[Wherein, R represents a linear or branched alkyl group or alkenyl group having 5 to 38 carbon atoms, A represents an alkylene group having 2 to 4 carbon atoms, and n represents an average added mole number of alkylene oxide of 1 or more. ]
Examples of the alkylene oxide adduct of the higher alcohol include the above-mentioned higher alcohol ethylene oxide or propylene oxide adduct, and an ethylene oxide adduct having an average addition mole number of 1 to 15 is preferable.

Examples of the catalyst used for the addition reaction between the higher alcohol and the alkylene oxide include homogeneous aqueous solutions of alkali hydroxides such as sodium hydroxide and potassium hydroxide, with aqueous potassium hydroxide being preferred.
The catalyst aqueous solution is used in an amount of usually 0.001 to 0.05 mol, preferably 0.005 to 0.02 mol per 1 mol of higher alcohol as alkali hydroxide, depending on the concentration. When the amount of the catalyst aqueous solution used is too large, it takes time for the dehydration step, and a large amount of acid is required for neutralization of the reaction product after the addition reaction, which is not preferable.

  In the method of the present invention, the carbonyl value of the raw material higher alcohol is 60 ppm or less, and the water concentration in the reaction raw material mixture when the alkylene oxide is brought into contact with the reaction raw material mixture containing the higher alcohol and the catalyst is less than 200 ppm. is important.

  The carbonyl value of the reaction raw material mixture is generally derived from carbonyl group-containing compounds such as aldehydes and ketones contained in the raw material higher alcohol. These carbonyl group-containing compounds are aldehydes and carboxylic acids that are generated by being partially oxidized according to the storage state when the alcohol is stored for a long period of time, or unreacted aldehydes derived from the alcohol production process. Therefore, as the raw material higher alcohol, a higher alcohol from which the carbonyl group-containing compound contained therein is removed or reduced, that is, a high-quality alcohol having a low carbonyl value is used, so that the polyalkylene glycol in the target alkylene oxide adduct is used. The amount of by-products can be reduced.

The carbonyl value of the higher alcohol is usually 60 ppm or less, preferably 40 ppm or less, more preferably 20 ppm or less. When the carbonyl value exceeds 60 ppm, polyalkylene glycol such as polyethylene glycol which is a by-product in the target alkylene oxide adduct is not preferable.
As a method for removing the carbonyl group-containing compound in the higher alcohol, a known method can be employed, for example, a method of hydrogenating aldehyde or the like, a method of distillation purification, an adsorption separation method using an ion exchange resin, and the like. It is done. A higher quality higher alcohol can also be obtained by the method described in JP-A No. 2003-12582, for example.

    Furthermore, in some cases, higher alcohols contain peroxides generated by auto-oxidation depending on storage conditions, etc., and the presence of peroxides tends to produce by-products during the production of alkylene oxide adducts. Become. Therefore, it is preferable to reduce the peroxide content in the higher alcohol, and the peroxide amount is usually 10 ppm or less, preferably 5 ppm or less, more preferably 1 ppm or less. When the amount of peroxide exceeds 10 ppm, polyalkylene glycol such as polyethylene glycol which is a by-product in the target alkylene oxide adduct increases, which is not preferable.

  Examples of the method for reducing the amount of peroxide include a method of decomposing by adding a catalyst such as mineral acid, transition metal ion, transition metal oxide and noble metal and heating, a method of decomposing by adding a reducing agent, and the like. Are known.

  In the method of the present invention, it is necessary that the water concentration in the reaction raw material mixture is less than 200 ppm. If the concentration is too high, polyalkylene glycol such as polyethylene glycol which is a by-product in the target alkylene oxide adduct is produced. It is not preferable because it increases. The water concentration in the reaction raw material mixture is usually less than 200 ppm, preferably 100 ppm or less, more preferably 60 ppm or less.

  The water concentration in the reaction raw material mixture can be adjusted by dehydrating the mixture of the higher alcohol and the catalyst aqueous solution. The dehydration treatment is performed by charging a raw material higher alcohol and an aqueous catalyst solution into a reactor, for example, an autoclave, and then purging with nitrogen, and then preferably heating and maintaining the mixture at a predetermined temperature under a predetermined reduced pressure while stirring the mixture. . As operation conditions, for example, pressure: 2.7 to 6.7 kPa · abs, temperature: held at 70 to 90 ° C. for at least 5 minutes, and then pressure: 0.7 to 4.0 kPa · abs, temperature: 90 to It is shown to be 120 ° C. and maintained at that pressure, temperature for at least another 10 minutes.

In the addition reaction of a higher alcohol and an alkylene oxide by the method of the present invention, a raw material higher alcohol and an aqueous catalyst solution are charged into a reactor (for example, an autoclave), and the air in the reactor is replaced with an inert gas such as nitrogen. The reaction material mixture in the reactor is dehydrated as described above to adjust the water concentration. Next, the inside of the reactor is adjusted to a predetermined temperature and pressure, and alkylene oxide is introduced into the raw material reaction mixture in which the water concentration is adjusted to cause addition reaction.
The addition reaction temperature is usually 80 to 200 ° C., preferably 120 to 190 ° C., and the pressure is about normal pressure (atmospheric pressure) to about 0.6 MPaG. After the supply of the alkylene oxide is stopped, the reaction temperature is maintained at the reaction temperature as it is for a desired time (also referred to as “aging”) in some cases in order to sufficiently achieve the reaction.

  Next, the reaction temperature is returned to room temperature, and the reaction product containing the desired alkylene oxide adduct is taken out. Although the reaction product can be used as it is depending on the intended use, it is usually used after neutralization to near neutrality (pH = 5 to 9) by a neutralizing agent such as an acid. The neutralized reaction product (also referred to as a crude alkylene oxide adduct) may be subjected to a purification treatment for removing the catalyst or the like by an adsorption treatment with an adsorbent as necessary to obtain a purified alkylene oxide adduct.

  The alkylene oxide adduct obtained by the method of the present invention has a low content of polyalkylene glycol as a by-product, can be used as a product as it is, and can be applied to many uses. In addition, the low content of polyethylene glycol having a molecular weight of 1000 or more as a by-product is an extremely useful alkylene oxide adduct in terms of improving storage stability and suppressing an increase in viscosity when blended as a cleaning agent. .

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to a following example, unless the summary is exceeded.
The measuring method of the physical property in the following Example is as follows.

Carbonyl number measurement method:
1 g of a sample is precisely weighed, weighed into a 25 ml volumetric flask, added with 4 ml of absolute ethanol and 2 ml of 2,4-dinitrophenylhydrazine, and then kept at 75 ° C. for 10 minutes. Thereafter, the mixture is cooled to room temperature, and a solution prepared from 47.2 g of potassium hydroxide, 250 ml of water and 600 ml of ethanol is added to the marked line and left for 20 minutes. As a blank test, the same operation is performed using 1 ml of ethanol instead of the sample. Absorbance is measured at a wavelength of 480 nm using a blank solution as a control solution using a spectrophotometer. The carbonyl value (C = O mass ppm) is read from a calibration curve prepared using dodecyl aldehyde.

Peroxide concentration measurement method:
20 g of the sample is precisely weighed, weighed into a 300 ml conical flask with a stopper, and 12 ml of chloroform is added with nitrogen sealing to dissolve the sample. Next, 18 ml of glacial acetic acid and 1 ml of saturated potassium iodide solution are added, sealed and left in a cool dark place for 5 minutes. Next, 75 ml of distilled water is added, sealed and shaken, and titrated with 0.002N sodium thiosulfate solution. As a blank test, the same operation is performed without adding a sample.
The peroxide value is calculated by the following formula.
Peroxide value (meq / kg) = (A−B) × N × f × 1000 / S
Oxygen conversion (O ₂ ppm) = Peroxide value (meq / kg) × 8
A: Titration of sodium thiosulfate solution required for titration of sample (ml)
B: Titration volume of sodium thiosulfate solution required for blank test (ml)
N: Normality of sodium thiosulfate solution f: Factor of sodium thiosulfate solution S: Weight of sample (g)

Method for measuring moisture concentration in reaction mixture:
Karl Fischer method Measured in accordance with the Karl Fischer method defined in JIS K2275 (crude oil and chemical products-moisture test method).

Measuring method of polyethylene glycol concentration:
Using a high performance liquid chromatograph, polyethylene glycol having a molecular weight of 1000 or more is quantified by an absolute calibration curve method.

For example, the following chromatographic conditions can be used.
Column: 1) and 2) columns connected in series 1) Inert sill ODS (particle size 5 μm) Length 150 mm × Inner diameter 4.6 mm
2) Asahipak GS-220H (particle size 9 μm) length 250 mm × inner diameter 7.6 mm
Detector: RI (differential refractometer)
Measurement temperature: room temperature Mobile phase: methanol: water = 8: 2 (volume%)
Flow rate: 1.0 ml / min Sample injection volume: 100 μl
Quantification method: Absolute calibration curve method using PEG-1000 as a standard substance

[Example 1]
Higher alcohol and catalyst charging operation In an autoclave with a stainless steel electromagnetic induction rotary stirrer with an internal capacity of 1500 mL, Neodol 23 with a carbonyl value of 40 ppm and a peroxide concentration of 0.7 ppm [trade name Shell Alcohol High Alcohol, C ₁₂ alcohol / C ₁₃ alcohol = 40% / 60% (wt%)] to 1.82g were charged KOH aqueous solution (concentration 48 wt%) as 300.0g and a catalyst, nitrogen-substituted [(temperature 30 ° C., "0.3 MPaG → 0 MPaG ") was repeated 3 times].

Dehydration operation:
The temperature is raised while stirring the autoclave, held at 70 ° C., 2.7 kPa · abs for 5 minutes, then heated to 110 ° C., the pressure is reduced to 0.7 kPa · abs, and held for 30 minutes. The reaction raw material mixture of alcohol and aqueous catalyst solution was dehydrated. The water concentration in the mixture after dehydration was 48 ppm.
Reaction operation:
Thereafter, the inside of the autoclave was returned to atmospheric pressure using nitrogen gas, and the temperature was raised to 155 ° C. Then, supply of ethylene oxide (purity of 99.9% or more) was started. While maintaining the reaction temperature at 155 ° C. and the pressure at 0.5 MPaG, 407.5 g of ethylene oxide was supplied. The supply of ethylene oxide was stopped, and the reaction temperature was kept at 155 ° C. for 30 minutes (hereinafter referred to as “aging”), and then cooled to room temperature.

Neutralization operation:
The reaction solution extracted from the autoclave was neutralized by adding 0.94 g of 99.8% glacial acetic acid to obtain a product containing an ethylene oxide adduct (hereinafter referred to as a crude ethylene oxide adduct).
Analysis operations:
As a result of conducting HPLC measurement of the obtained crude ethylene oxide adduct, the polyethylene glycol concentration was 0.25% by mass. The results are shown in Table 1.

[Example 2]
The dehydration operation of Example 1 was performed in the same manner as in Example 1 except that the holding time at 110 ° C. and 0.7 kPa · abs was 2 minutes.
The water concentration in the reaction raw material mixture after the dehydration operation was 90 ppm. Moreover, the polyethylene glycol concentration in the obtained crude ethylene oxide adduct was 0.37% by mass. The results are shown in Table 1.

[Example 3]
The dehydration operation of Example 1 was performed in the same manner as in Example 1 except that the temperature was increased with stirring and the temperature was maintained at 70 ° C. and 2.7 kPa · abs for 5 minutes.
The water concentration in the reaction raw material mixture after the dehydration operation was 166 ppm. Moreover, the polyethylene glycol concentration in the obtained crude ethylene oxide adduct was 0.54% by mass. The results are shown in Table 1.

[Example 4]
In the dehydration operation of Example 1, the temperature was increased while stirring, and the same procedure as in Example 1 was performed except that the temperature was maintained at 70 ° C. and 2.7 kPa · abs for 3 minutes.
The water concentration in the reaction raw material mixture after the dehydration operation was 195 ppm. Further, the polyethylene glycol concentration in the obtained crude ethylene oxide adduct was 0.68% by mass. The results are shown in Table 1.

[Comparative Example 1]
The dehydration operation of Example 1 was performed in the same manner as in Example 1 except that the temperature was increased with stirring and the temperature was maintained at 70 ° C. and 2.7 kPa · abs for 2 minutes.
The water concentration in the reaction raw material mixture after the dehydration operation was 296 ppm. Moreover, the polyethylene glycol concentration in the obtained crude ethylene oxide adduct was 1.01% by mass. The results are shown in Table 1.

[Example 5]
Except for using higher alcohol, Dovanol 23 with a carbonyl value of 28 ppm and a peroxide concentration of 6 ppm [trade name: Higher alcohol manufactured by Mitsubishi Chemical Corporation, C ₁₂ alcohol / C ₁₃ alcohol = 40% / 60% (wt%)]. The same operation as in Example 1 was performed.
The water concentration in the reaction raw material mixture after the dehydration operation was 48 ppm. Further, the polyethylene glycol concentration in the obtained crude ethylene oxide adduct was 0.15% by mass. The results are shown in Table 1.

[Example 6]
In Example 5, it carried out similarly to Example 5 except having used this dovanol 23 what was hold | maintained at 65 degreeC in air presence for 7 days instead of dovanol 23.
The carbonyl value of dovanol 23 after being used for 7 days was 35 ppm, and the peroxide concentration was 7 ppm. The water concentration in the reaction raw material mixture after the dehydration operation was 53 ppm. Moreover, the polyethylene glycol concentration in the obtained crude ethylene oxide adduct was 0.22% by mass. The results are shown in Table 1.

[Example 7]
In Example 5, it carried out similarly to Example 5 except having used this dovanol 23 what was hold | maintained at 65 degreeC in air presence for 10 days instead of dovanol 23.
The carbonyl value of dovanol 23 after being used for 10 days was 55 ppm, and the peroxide concentration was 9 ppm. The water concentration in the reaction raw material mixture after the dehydration operation was 44 ppm. Moreover, the polyethylene glycol concentration in the obtained crude ethylene oxide adduct was 0.67% by mass. The results are shown in Table 1.

[Comparative Example 2]
In Example 5, it carried out similarly to Example 5 except having used this dovanol 23 what was hold | maintained at 40 degreeC in air presence for 60 days instead of dovanol 23.
The carbonyl value of dovanol 23 after being used for 60 days was 117 ppm, and the peroxide concentration was 56 ppm. The water concentration in the reaction raw material mixture after the dehydration operation was 41 ppm. Moreover, the polyethylene glycol concentration in the obtained crude ethylene oxide adduct was 1.05% by mass. The results are shown in Table 1.

Claims (3)

  In the method for producing an alkylene oxide adduct by reacting a higher alcohol and an alkylene oxide, the carbonyl value of the higher alcohol is 60 ppm or less, and the alkylene oxide is brought into contact with a reaction raw material mixture containing the higher alcohol and a catalyst. A method for producing an alkylene oxide adduct, wherein the water concentration in the reaction raw material mixture is less than 200 ppm.   The method for producing an alkylene oxide adduct according to claim 1, wherein the reaction raw material mixture containing the higher alcohol and the catalyst aqueous solution is contacted with the alkylene oxide after adjusting the water concentration by dehydration.   The method for producing an alkylene oxide adduct according to claim 1 or 2, wherein the higher alcohol has a peroxide concentration of 10 ppm or less.