JPH09249636A - Method for producing N-alkylamide alkanol sulfate ester salt - Google Patents

Abstract

(57) [Abstract] [Problem] N-, which has a good odor and is excellent in storage stability.
Provided is a method for producing an alkylamide alkanol sulfate ester salt. SOLUTION: An N-alkylamide alkanol sulfate obtained by sulfating an N-alkylamide alkanol with a sulfating agent is neutralized with a basic substance in an aqueous solution to give an N- represented by the general formula (II). An aqueous solution of alkylamidoalkanol sulfate ester salt having a pH of 5 to 8 is obtained. Embedded image [R ¹ is a C _6-22 alkyl group or the like, R ² is H or a C _1-22 alkyl group, R ³ is a C _1-5 alkylene group, R ⁴ is a C _2-3 alkylene group, n Represents a number from 0 to 50, and M represents a cation. ]

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an N-alkylamide alkanol sulfate ester salt, and more particularly to a method for producing an N-alkylamide alkanol sulfate ester salt having a good odor and having no problem in storage stability. Regarding the method.

[0002]

2. Description of the Related Art In recent years,
An N-alkylamide alkanol sulfate ester salt has been reported as a surfactant having excellent foaming properties and high safety, which is used for various detergents for washing hair, body, dishware, etc. (JP-A-7-267917). Gazette). This surfactant is obtained by further neutralizing the N-alkylamide alkanol sulfate obtained by sulfating N-alkylamide alkanol with a sulfating agent, but the odor was not sufficiently satisfactory. Further, immediately after the synthesis, even if the odor was good, the odor was deteriorated by storing it.

Therefore, an object of the present invention is to have a good odor,
Another object of the present invention is to provide a method for producing an N-alkylamidoalkanol sulfate ester salt which has no problem in storage stability.

[0004]

Under the present circumstances, as a result of intensive studies, the present inventors can solve the above problems by adjusting the pH of the N-alkylamidoalkanol sulfate ester salt aqueous solution to 5-8. Heading
The present invention has been completed. That is, the present invention provides a method for producing an N-alkylamide alkanol sulfate ester salt, which comprises the following steps (A) and (B).

Step (A): General formula (I)

[0006]

Embedded image

[In the formula, R ¹ represents a linear or branched alkyl group having 6 to 22 carbon atoms, an alkenyl group, a hydroxyalkyl group, or an alkylphenyl group having 8 to 12 carbon atoms in the alkyl group. R ^{2 represents a} hydrogen atom, or a linear or branched alkyl group having 1 to 22 carbon atoms, an alkenyl group, a hydroxyalkyl group, or an alkylphenyl group having 8 to 12 carbon atoms in the alkyl group. R ³ : represents a linear or branched alkylene group having 1 to 5 carbon atoms. R ^4: represents a linear or branched alkylene group having 2 to 3 carbon atoms, n number of R ⁴ may be the same or different. n: 0 indicating the average number of moles of alkylene oxide added
Any number of 50. ] The process of sulphating N-alkyl amide alkanol represented by these with a sulfating agent, and obtaining N-alkyl amide alkanol sulfuric acid ester.

Step (B): N-obtained in step (A)
Alkylamido alkanol sulfate ester is neutralized with a basic substance in an aqueous solution to give a compound of general formula (II)

[0009]

Embedded image

[Wherein R ¹ , R ² , R ³ , R ⁴ and n are as defined above. M: indicates a cation. ] The process of obtaining the aqueous solution of N-alkyl amide alkanol sulfuric acid ester salt represented by the following at pH 5-8.

[0011]

Embodiments of the present invention will be described below in detail.

Step (A): This step is a step of sulfating an N-alkylamide alkanol represented by the general formula (I) with a sulfating agent to obtain an N-alkylamide alkanol sulfate.

In the general formula (I), R ¹ has 6 to 22 carbon atoms.
The straight-chain or branched-chain alkyl group, alkenyl group, hydroxyalkyl group, or alkylphenyl group having 8 to 12 carbon atoms of the alkyl group is specifically described as a hexyl group, an octyl group, a decyl group, or a dodecyl group. , Tetradecyl group, hexadecyl group, octadecyl group, isostearyl group, eicosyl group, docosyl group, oleyl group, 2-ethylhexyl group, 12-hydroxydodecyl group, nonylphenyl group, and the like, straight chain having 6 to 22 carbon atoms Alternatively, a branched chain alkyl group is preferable from the viewpoint of foaming property, and a straight chain alkyl group having 8 to 18 carbon atoms, and further preferably a straight chain alkyl group having 10 to 14 carbon atoms is preferable.

R ² represents a hydrogen atom or a linear or branched alkyl group having 1 to 22 carbon atoms, an alkenyl group, a hydroxyalkyl group, or an alkylphenyl group having 8 to 12 carbon atoms in the alkyl group. , Specifically, hydrogen atom, methyl group, ethyl group, propyl group, butyl group, isobutyl group,
In addition to the hydroxyethyl group, the functional groups exemplified above for R ¹ can be mentioned, and a hydrogen atom is particularly preferable from the viewpoints of foaming property, safety and chemical stability.

R ³ represents a linear or branched alkylene group having 1 to 5 carbon atoms, specifically, methylene group, ethylene group, propylene group, butylene group, pentylene group, --CH ₂ C.
H (CH ₃ ) CH ₂ CH ₂ — includes a branched 2-methylbutylene group and the like, and particularly in view of foaming property and chemical stability, a methylene group or —CH ₂ CH (CH ₃ ) CH. A branched 2-methylbutylene group represented by ₂ CH ₂ — is preferable, and a methylene group is more preferable.

R ⁴ represents a linear or branched alkylene group having 2 to 3 carbon atoms, and specific examples thereof include an ethylene group and a branched propylene group. n is an arbitrary number of 0 to 50 which represents the average number of moles of alkylene oxide added, and is preferably an arbitrary number of 0 to 10 in view of foamability, safety and chemical stability, and more preferably n = 0. The n R ^{4 s} may be the same or different.

The following compounds may be mentioned as specific examples of the N-alkylamidoalkanol represented by the general formula (1).

[0018]

Embedded image

[0019]

[Chemical 6]

Among these N-alkylamidoalkanols represented by the general formula (I), R ¹ is a linear alkyl group having 8 to 18 carbon atoms, R ² is a hydrogen atom, R ³ is a methylene group, and n is 0
And a compound in which R ¹ is a linear alkyl group having 10 to 14 carbon atoms is preferable.

The sulfating agent used in the sulfation reaction of the present invention is not particularly limited, but liquid SO ₃ , SO
Examples thereof include ₃ gas, chlorosulfonic acid, fuming sulfuric acid, and the like. SO ₃ gas and chlorosulfonic acid are preferable, and chlorosulfonic acid is more preferable. By sulfating the N-alkylamidoalkanol with the above sulfating agent,
N-alkyl amide alkanol sulfuric acid ester can be obtained.

It is preferable to carry out this sulfation reaction in the presence of a solvent, since it is possible to suppress the solidification or thickening of the N-alkylamide alkanol or its sulfated N-alkylamide alkanol sulfate ester. Examples of the solvent used include organic chlorine solvents such as chloroform, dichloromethane and 1,2-dichloroethane;
Aprotic polar solvent such as dimethylformamide; pentane, hexane, heptane, octane, isopentane,
Examples thereof include linear, branched or cyclic alkanes having 5 to 10 carbon atoms such as 2-methylpentane, 3-methylpentane, cyclopentane, cyclohexane, cycloheptane and methylcyclohexane. Among these, linear, branched or cyclic alkanes having 5 to 10 carbon atoms are preferable, and hexane and cyclohexane are more preferable in view of boiling point and industrial availability.

The amount of the solvent used is N represented by the general formula (I).
It is preferably 1 to 20 times by weight, more preferably 2 to 15 times by weight, relative to the alkylamidoalkanol. In this case, the N-alkylamide alkanol represented by the general formula (I), its sulfated N-alkylamide alkanol sulfate, or the sulfating agent does not necessarily have to be dissolved in a solvent and may be a liquid or a solid. If it is dispersed in, the sulfation reaction can be easily performed. Solvent amount is 1
It can be dispersed as a liquid or a solid efficiently at up to 20 times the weight.

In the sulfation reaction of the N-alkylamidoalkanol represented by the general formula (I) with a sulfating agent, N-
The ratio of the alkylamidoalkanol to the sulfating agent is not particularly limited, but it is preferable that the reaction rate of the N-alkylamidoalkanol is 90% or more and that an excessive unreacted sulfating agent does not remain in the system. In this case, the reaction temperature for sulfation is not particularly limited, but it is preferably performed at less than 50 ° C.

Step (B): In the step (B), the N-alkylamide alkanol sulfate obtained in the step (A) is neutralized with a basic substance in an aqueous solution to give a compound represented by the general formula (II).
Is a step of obtaining an aqueous solution of N-alkylamide alkanol sulfate ester salt represented by

In the general formula (II), the cation represented by M is an alkali metal, an alkaline earth metal, ammonium, an alkanolammonium having a total carbon number of 2 to 9, an alkylammonium or an alkenylammonium having a total carbon number of 1 to 22. , An alkyl- or alkenyl-substituted pyridinium having 1 to 18 carbon atoms, a basic amino acid and the like, and an alkali metal such as Na and K, ammonium, and an alkanol ammonium having 2 to 9 carbon atoms are preferable.

In this step, as the basic substance used for neutralization, hydroxides, carbonates or bicarbonates of alkali metals or alkaline earth metals, ammonia, alkanolamines having 2 to 9 carbon atoms in total, Alkylamine or alkenylamine having 1 to 22 carbon atoms, total carbon number 1
To 18 alkyl- or alkenyl-substituted pyridines or basic amino acids, and specific examples thereof include inorganic materials such as sodium hydroxide, potassium hydroxide, lithium hydroxide, barium hydroxide, sodium hydrogen carbonate, sodium carbonate and potassium carbonate. Alkali or ammonia, monoethanolamine, diethanolamine, triethanolamine, methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, decylamine, dodecylamine, tetradecylamine, hexadecylamine, octadecylamine, basic amino acids, etc. Of these, ammonia, sodium hydroxide, potassium hydroxide, monoethanolamine, diethanolamine and triethanolamine are preferable. These are used as an aqueous solution to neutralize the sulfate ester.

The amount of the basic substance used is not particularly limited, but the pH of the aqueous solution obtained by the neutralization is finally adjusted to 5 to 5.
It should be adjusted to 8, preferably 5.5 to 7. If the pH is less than 5, decomposition of the produced N-alkylamide alkanol sulfuric acid ester salt proceeds, resulting in poor storage stability.
If the pH exceeds 8, the odor will be deteriorated, and the odor will be further deteriorated by storing it.

When a solvent is used in the sulfation reaction, a lower alcohol is used as a demulsifier during neutralization, and after the neutralization, a solvent layer and an aqueous solution of N-alkylamide alkanol sulfuric acid ester salt containing a lower alcohol are formed. It is preferable to separate. Further, it is further preferable that thereafter, the lower alcohol in the N-alkylamidoalkanol sulfate ester aqueous solution layer is removed. The method for removing the lower alcohol is not particularly limited, and examples thereof include distillation and separation with a membrane. As the lower alcohol used here, an alcohol having 1 to 4 carbon atoms is preferable, and methanol and ethanol are particularly preferable.

In the step (B), it is also possible to carry out a purification treatment with at least one selected from the group consisting of an oxidizing agent and a reducing agent at the same time as or after the neutralization, and then to adjust the pH to 5-8. .

Examples of the oxidizing agent used here include sodium hypochlorite, hydrogen peroxide, ozone and the like, and examples of the reducing agent include borohydride salts such as sodium borohydride. The addition amount of the oxidizing agent and / or the reducing agent is preferably 10 ppm to 1% by weight with respect to the N-alkylamide alkanol sulfate ester. The treatment time is preferably 0.1 to 5 hours in each of the oxidizing agent treatment and the reducing agent treatment, and the treatment temperature is preferably 20 to 60 ° C. Oxidizer and /
Alternatively, the pH of the aqueous solution obtained after performing the purification treatment with a reducing agent must be adjusted to 5-8. If the pH is less than 5, decomposition of the produced N-alkylamide alkanol sulfuric acid ester salt proceeds, resulting in poor storage stability. Also,
If the pH exceeds 8, the odor will be deteriorated, and the odor will be further deteriorated by storing it. When the pH is out of the range of 5 to 8 after the treatment with the oxidizing agent and / or the reducing agent, the pH is adjusted. The acid or basic substance used for the adjustment is not particularly limited, but if the pH of the obtained aqueous solution is less than 5, the basic substance used for neutralization is preferable. Also,
When the pH of the obtained aqueous solution exceeds 8, phosphoric acid, sulfuric acid, etc. are preferable.

[0032]

Industrial Applicability According to the present invention, it is possible to produce an N-alkylamide alkanol sulfuric acid ester salt having a good odor and no problem in storage stability.
The N-alkylamide alkanol sulfuric acid ester salt obtained by the method of the present invention has a good odor and storage stability, and therefore can be effectively used as a cleaning base.

[0033]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

Examples 1 to 7 In a 5 liter flask equipped with a stirrer, cooling tube, thermometer, dropping funnel and nitrogen blowing tube, as shown in Table 1, the amount of each solvent and N-alkylamidoalkanol were determined.
1.0 mol was charged to prepare a suspension. In this case, if the N-alkylamidoalkanol was solid at room temperature, it was heated and dissolved in advance and added dropwise to the solvent.
Then, after adjusting the temperature to 40 ℃, chlorosulfonic acid 1.
0 mol was added dropwise over about 1 hour, and after completion of the addition, 0.5 m of nitrogen was added.
The reaction was stirred for 3 hours while blowing into the reaction solution with ol / Hr, and the reaction rate was measured by the method shown below. Next, the reaction product was neutralized with sodium hydroxide or potassium hydroxide at 30 ° C., 450 g of ethanol and 620 g of water were added, and the solvent layer and the N-alkylamide alkanol sulfuric acid ester salt aqueous solution layer were separated. At this time, the pH of the aqueous solution of the N-alkylamide alkanol sulfate ester aqueous solution was adjusted within the range of 5 to 8 as shown in Table 1. After that, the pH-adjusted N-alkylamide alkanol sulfuric acid ester salt aqueous solution layer was extracted, and part of water and ethanol were distilled off at 200 mmHg to prepare a 30 wt% N-alkylamide alkanol sulfuric acid ester salt aqueous solution.

Table 1 shows reaction conditions, reaction rates, odors before and after storage, and decomposition rates after storage. The reaction rate was measured by HPLC, and the raw material N-alkylamidoalkanol and N were used.
-Calculated from the peak area ratio of alkylamidoalkanol sulfate. In the odor evaluation, a sensory evaluation test was performed. The storage test was carried out at 50 ° C. for 20 days, the odor sensory test and the decomposition rate were measured by HPLC after storage, and the peaks of the raw material N-alkylamide alkanol and N-alkylamide alkanol sulfate ester were measured. The decomposition rate was calculated by the following formula from the reaction rate calculated from the area ratio and the reaction rate before the storage test. The same method was used in the following examples and comparative examples.

[0036]

[Equation 1]

[0037]

[Table 1]

Example 8 A sulfation reaction was carried out without using a solvent. That is, the thermometer,
1 mol of N-lauryl-2-hydroxyacetic acid amide powdered in a kneader equipped with a SO ₃ gas blowing tube (243.
4g), adjust to 40 ° C, and inject SO ₃ gas 3
A time reaction was performed. At this time, the reaction rate was 92.3%.
Next, the N-alkyl amide alkanol sulfate ester salt concentration is neutralized with an aqueous sodium hydroxide solution so that the concentration becomes 30% by weight, and then 1.73 g of 10% sodium hypochlorite is added, and the mixture is kept at 40 ° C. for 1 hour. After the treatment, 0.26 g of sodium borohydride powder was further added, and the treatment was carried out at 40 ° C. for 1 hour. The pH of the aqueous solution was 10.5. Then, the pH was adjusted to 6.6 with 85% phosphoric acid. The odor evaluation of the obtained N-alkylamide alkanol sulfate ester aqueous solution was good. As a result of a 20-day storage test at 50 ° C, the decomposition rate was 0.1%, there was almost no decomposition, and the odor was good.

Comparative Example 1 1 mol of N-lauryl-2-hydroxyacetic acid amide (243.
4 g) was added dropwise to a flask charged with 1947.1 g of n-hexane as a solvent to give a suspension. 40 ℃
Then, 1.0 mol (116.5 g) of chlorosulfonic acid was added dropwise over 1 hour. After completion of dropping, nitrogen was blown into the reaction solution at 0.5 mol / Hr to carry out stirring reaction for 3 hours. The reaction rate at this time was 98.2%. Next, it neutralized with sodium hydroxide by the method similar to Examples 1-7, and the N-alkyl amide alkanol sulfuric acid ester salt aqueous solution layer was extracted. The pH was 4.5, and thereafter, distillation removal was carried out as in Examples 1 to 7 to prepare a 30 wt% aqueous solution. As a result, p
There was no change in H, which was 4.5. The obtained aqueous solution of N-alkylamide alkanol sulfate ester salt had a good odor, but as a result of a storage test at 50 ° C for 20 days, the decomposition rate was 30.5%, and the decomposition occurred considerably, and the odor was also increased. An offensive odor was observed.

Comparative Example 2 1 mol of N-lauryl-2-hydroxyacetic acid amide which had been previously dissolved by heating in the same apparatus as in Examples 1 to 7 (243.
4 g) was added dropwise to a flask charged with 1947.1 g of n-hexane as a solvent to give a suspension. 40 ℃
Then, 1.0 mol (116.5 g) of chlorosulfonic acid was added dropwise over 1 hour. After completion of dropping, nitrogen was blown into the reaction solution at 0.5 mol / Hr to carry out stirring reaction for 3 hours. The reaction rate at this time was 98.2%. Next, it neutralized with sodium hydroxide by the method similar to Examples 1-7, and the N-alkyl amide alkanol sulfuric acid ester salt aqueous solution layer was extracted. The pH was 9.7, and thereafter, distillation was performed in the same manner as in Examples 1 to 7 to prepare a 30% by weight aqueous solution. As a result, p
There was no change in H, which was 9.7. The obtained N-alkylamide alkanol sulfate ester aqueous solution had an offensive odor. As a result of a storage test conducted at 50 ° C for 20 days, the decomposition rate was 0.5%, and there was almost no decomposition, but the odor was stronger than before storage.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yozumi Mizushima 1334 Minato Minato, Wakayama, Wakayama Kao Research Institute

Claims (5)

[Claims] 1. A process for producing an N-alkylamide alkanol sulfate ester salt, which comprises the following steps (A) and (B): Step (A): General Formula (I) [In the formula, R ¹ represents a linear or branched alkyl group having 6 to 22 carbon atoms, an alkenyl group, a hydroxyalkyl group, or an alkylphenyl group having 8 to 12 carbon atoms in the alkyl group. R ^{2 represents a} hydrogen atom, or a linear or branched alkyl group having 1 to 22 carbon atoms, an alkenyl group, a hydroxyalkyl group, or an alkylphenyl group having 8 to 12 carbon atoms in the alkyl group. R ³ : represents a linear or branched alkylene group having 1 to 5 carbon atoms. R ^4: represents a linear or branched alkylene group having 2 to 3 carbon atoms, n number of R ⁴ may be the same or different. n: 0 indicating the average number of moles of alkylene oxide added
Any number of 50. ] The process of sulphating N-alkyl amide alkanol represented by these with a sulfating agent, and obtaining N-alkyl amide alkanol sulfuric acid ester. Step (B): The N-alkylamide alkanol sulfate obtained in step (A) is neutralized with a basic substance in an aqueous solution to give a compound represented by the general formula (II): [In the formula, R ¹ , R ² , R ³ , R ⁴ , and n are as defined above. M: indicates a cation. ] The process of obtaining the aqueous solution of N-alkyl amide alkanol sulfuric acid ester salt represented by the following at pH 5-8. 2. In the step (B), a purification treatment is performed using at least one selected from the group consisting of an oxidizing agent and a reducing agent, simultaneously with or after the neutralization, and then the pH is adjusted to 5 to 8. The manufacturing method according to claim 1. 3. The step (A) is carried out in the presence of a solvent, a lower alcohol is added when neutralizing the step (B), and a solvent layer and an aqueous solution of a N-alkylamide alkanol sulfate ester salt containing the lower alcohol are added. The method according to claim 1 or 2, wherein the method is separated into layers. 4. The production method according to claim 3, wherein the lower alcohol is removed from the N-alkylamide alkanol sulfate ester salt aqueous solution layer obtained in step (B). Wherein R ¹ is a linear alkyl group having 8 to 18 carbon atoms, R ²
Is a hydrogen atom, R ³ is a methylene group, and n is 0.
4. The production method according to any one of 4.