JPH10182590A - Pale alpha-sulfofatty acid alkylester salt and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an α-sulfofatty acid alkyl ester salt having pale color close to white and produce a method for producing the alkyl ester salt. SOLUTION: When an α-sulfofatty acid alkyl ester salt is produced from a saturated fatty acid alkyl ester represented by the formula, R1 CH2 COOR2 [R1 is a 6-24C alkyl group; R2 is a 1-6C alkyl group], at least aging process is carried out in the presence of at least one kind of compound selected from a group comprising a phosphoric acid compound, an organic phosphorus compound, an carbonate compound, a boric acid compound, a boron compound, a silicic acid compound and a silicon compound as a coloration suppressant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an .alpha.-sulfofatty acid alkyl ester salt and a method for producing the same, and more particularly to a light-colored .alpha.-sulfofatty acid alkyl ester salt having a color close to white and a method for producing the same.

[0002]

2. Description of the Related Art Alkyl α-sulfofatty acid ester salts
Is one of its uses for surfactants, especially
High detergency, good biodegradability, environmental impact
Performance as a detergent material
Have been. This α-sulfofatty acid alkyl ester salt
Replaces fatty acid alkyl esters with SO _ThreeBy sulfonation
And then neutralized with alkali
It is.

[0003] The sulfonation mechanism of fatty acid alkyl esters is described in Smith and Stirton: JAO.
CS vol. 44, p. 405 (1967) and Schmi
d, Baumann, Stein, Dolhaine: Proceeding of the W
orld Surfactants Congress Munchen, vol. Two,
P. 105, Gel-nhausen, Kurle (1984) and H.
Yoshimura: Oil Chemistry (JJOCS), 41, 10 (199
As shown in 2), the reaction proceeds according to the following reaction scheme.

[0004]

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[0005] In this sulfonation reaction, when reacted with SO ₃ to fatty acid alkyl esters, but is efficient if react to form α- sulfofatty acid alkyl esters in position α of direct SO ₃ fatty acid esters, In fact, a reaction occurs first to be inserted into the alkoxy group, and SO ₃
A one-molecule adduct (hereinafter abbreviated as a one-molecule adduct) is produced. In the next step, it further reacts with SO ₃ to introduce a sulfone group at the α-position, thereby producing a SO ₃ biadduct (hereinafter abbreviated as a biadduct). Subsequently, SO ₃ inserted into the alkoxy group is eliminated to form an α-sulfofatty acid alkyl ester.

Here, the reaction proceeds rapidly until the above-mentioned bimolecular adduct is formed, but the reaction in which SO ₃ is eliminated from the bimolecular adduct to form an α-sulfofatty acid alkyl ester is extremely difficult. Therefore, in an actual reaction, it is necessary to use an excessive amount of a sulfonating gas such as SO ₃ gas. Further, it is necessary to promote the reaction from the saturated fatty acid alkyl ester to the bimolecular adduct formation step while introducing the sulfonated gas, and then provide an aging step to promote the elimination of SO ₃ .

In order to obtain the α-sulfofatty acid alkyl ester salt, the α-sulfofatty acid alkyl ester salt is obtained from the α-sulfofatty acid alkyl ester by neutralizing with an alkali after the aging step. However, the α-sulfofatty acid alkyl ester produced by the conventional method is markedly colored, and thus the α-sulfofatty acid alkyl ester salt obtained after alkali neutralization is also colored. When used as a detergent material, since the α-sulfofatty acid alkyl ester salt cannot be made into a product in a colored state, before or after this neutralization step, a bleaching step under severe conditions with hydrogen peroxide or the like is required. It is generally done.

That is, a conventional α-sulfofatty acid alkyl ester salt is produced through a sulfonation reaction of a fatty acid alkyl ester by a sulfonating gas introduction step and an aging step, followed by a neutralization step by alkali neutralization and a bleaching step. Is done. Then, during these steps, the ester bond is partially cleaved, so that by-products of α-sulfofatty acid or α-sulfofatty acid dialkaline cannot be avoided. Since the above-mentioned by-products have low detergency as a detergent active ingredient and poor water solubility, when these substances are produced in large amounts, it is possible to efficiently obtain α-sulfofatty acid alkyl ester salts suitable for detergents. Becomes difficult. Therefore, the bleaching step not directly related to the production of the α-sulfofatty acid alkyl ester salt can be simplified or omitted as much as possible to prevent the generation of these by-products,
preferable.

On the other hand, one of the causes of the coloring of the α-sulfofatty acid alkyl ester described above is due to the presence of an excessive sulfonated gas. It has also been confirmed that this coloring proceeds particularly during the aging step. However, it is essential that this ripening step be performed sufficiently to suppress by-products. That is, the α-sulfofatty acid alkyl ester is converted into an α-sulfofatty acid alkyl ester salt by neutralization with an alkali after the aging step, and at this time, when the above-mentioned bimolecular adduct remains,
For example, the reaction as shown in the following (X) occurs by alkali neutralization of sodium hydroxide or the like, and α-sulfofatty acid disoda having poor detergency and water solubility is produced. That is, when the SO ₃ elimination reaction in the aging step is insufficient and the neutralization is performed in a state where the bimolecular adduct is present in a large amount in the sulfonation reaction product, α-sulfofatty acid disoda is generated, It becomes difficult to obtain physical properties as a surfactant, for example, preferable detergency and penetrating power. Therefore, the most desired α-
The method for producing a sulfo fatty acid alkyl ester salt is a method capable of sufficiently performing an aging step, increasing a reaction rate, and simplifying or omitting a bleaching step. In this method, an α-sulfofatty acid alkyl ester salt can be produced from an α-sulfofatty acid alkyl ester which is not used.

[0010]

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Regarding the method for obtaining this light-colored α-sulfofatty acid alkyl ester salt, an inorganic sulfate (Japanese Patent Application Laid-Open No.
-43716), fatty acid amides (WO 90039)
67, pyridine (DE 4030852), thiodiglycol diester (DE Publication 422).
A method of performing a sulfonation reaction in the coexistence of such a method has been proposed. However, when fatty acid amide is used, a sufficient effect cannot be obtained unless the amount is large, and when pyridine is used, there is a problem in terms of odor, and the reaction rate and color tone are improved in other methods. The effects were not always satisfactory.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to provide a light-colored .alpha.-sulfofatty acid alkyl ester salt having a near-white color and a method for producing the same.

[0013]

Means for Solving the Problems The inventors of the present invention have found that, when a sulfonation reaction of a saturated fatty acid alkyl ester is carried out, at least in the aging step, a specific compound is coexisted as a coloring inhibitor to improve the color tone. And found that the present invention was completed.

That is, the following general formula (I): R ₁ CH ₂ COOR ₂ ... (I) (wherein R ₁ represents an alkyl group having 6 to 24 carbon atoms, and R ₂ represents 1 to 6 carbon atoms) and saturated fatty acid alkyl ester represented by the alkyl represents a group) of a sulfonating gas introduction step of contacting a sulfonating gas to desorb SO ₃ from SO ₃ bimolecular adduct after the sulfonating gas introducing step In the method for producing an α-sulfofatty acid alkyl ester salt having an aging step, at least the aging step, as a coloring inhibitor, a phosphoric acid compound, an organic phosphorus compound, a carbonate compound, a borate compound, a boron compound, a silicate compound, The solution to the above-mentioned problem is performed in the presence of at least one compound selected from the group consisting of silicon compounds.

Further, the phosphoric acid compound is preferably
Phosphates represented by the following general formulas (II), (III) and (IV), metaphosphates represented by the following general formula (V), and condensed phosphoric acids represented by the following general formulas (VI) and (VII) It is at least one compound selected from salts. _{M 3 PO 4 ··· (II)} MH 2 PO 4 ··· (III) M 2 HPO 4 ··· (IV) MPO 3 ··· (V) M 5 P 3 O 10 ··· (VI) M ₃ P ₃ O ₉ (VII) (wherein M represents a monovalent alkali metal or ammonium)

The organic phosphorus compound is preferably at least one compound selected from the compounds represented by the following formulas (VIII) and (IX). (RO) ₃ P (VIII) R ₃ P (IX) (wherein R represents hydrogen or a saturated or unsaturated straight-chain or side-chain hydrocarbon group having 1 or more carbon atoms.)

The carbonate compound is preferably at least one compound selected from the group consisting of carbonates, hydrogen carbonates, carbonate compounds and sodium potassium carbonate.
The boric acid compound is preferably at least one compound selected from borates and metaborates. Further, the boron compound is preferably at least one compound selected from trimethyl borate, sodium boron hydride, and potassium boron hydride.

The silicate compound is preferably
It is at least one compound selected from silicates, orthosilicates, and aluminosilicates. In addition, the silicon compound is preferably at least one compound selected from ethyl silicate and tetramethyl silicate.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. The method for producing an α-sulfofatty acid alkyl ester salt of the present invention comprises a sulfonating gas introduction step, an aging step,
A neutralization step, in which the color tone of the α-sulfofatty acid alkyl ester obtained especially after the aging step is improved,
As a result, a pale white α-sulfofatty acid alkyl ester salt can be obtained. This α-sulfofatty acid alkyl ester salt and a method for producing the same are represented by the following general formula (I): R ₁ CH ₂ COOR ₂ (I) wherein R ₁ represents an alkyl group having 6 to 24 carbon atoms. , R ₂ is SO ₃ bimolecular after the saturated fatty acid alkyl ester represented by an alkyl group having 1 to 6 carbon atoms), a sulfonating gas introduction step of contacting a sulfonating gas, the sulfonating gas introducing step A method for producing an α-sulfofatty acid alkyl ester salt having a ripening step of removing SO ₃ from an adduct, wherein at least the ripening step is performed in the presence of a coloring inhibitor selected from a specific compound. .

In the above saturated fatty acid alkyl ester, the fatty acid residue has 6 to 24 carbon atoms, the alcohol residue has 1 to 6 carbon atoms, and the total carbon number of both is 9 to 26. The alkyl esters of saturated fatty acids include animal fats and oils derived from beef tallow, fish oil, etc., vegetable fats and oils derived from coconut oil, palm oil, soybean oil, etc., and synthetic fatty acids derived from the oxo process of α-olefins. Any of alkyl esters and the like may be used, and there is no particular limitation. These include, for example, methyl or ethyl laurate, methyl or ethyl palmitate, methyl or ethyl stearate, methyl or ethyl hardened tallow fatty acid, methyl or ethyl hardened fish oil fatty acid, methyl or ethyl coconut fatty acid, -Methyl or ethyl fatty acid fatty acid; methyl or ethyl fatty acid palm kernel oil; These saturated fatty acid alkyl esters may be used alone or in a mixture, but the iodine value is preferably 0.5 or less, more preferably 0.1 or less, because the lower the iodine value, the more difficult it is to color during the production process. .

As the coloring inhibitor, a phosphoric acid compound,
At least one compound selected from the group consisting of organic phosphorus compounds, carbonate compounds, boric compounds, boron compounds, silicate compounds, and silicon compounds is used. The phosphoric acid compound is preferably represented by the following general formulas (II) and (II)
Phosphates represented by I) and (IV), represented by the following general formula (V)
A metaphosphate represented by the following general formulas (VI) and (VI)
At least one selected from the condensed phosphates represented by I)
Species of compound.

M ₃ PO ₄ ··· (II) MH ₂ PO ₄ ··· (III) M ₂ HPO ₄ ··· (IV) MPO ₃ ··· (V) M ₅ P ₃ O ₁₀ ··· (VI) M ₃ P ₃ O ₉ (VII) (wherein M represents a monovalent alkali metal such as sodium, potassium, lithium or ammonium).

The organic phosphorus compound is preferably at least one compound selected from the organic phosphorus compounds represented by the following general formulas (VIII) and (IX). (RO) ₃ P ... (VIII) R ₃ P ... (IX) (wherein, R is hydrogen or a saturated or unsaturated straight chain having 1 or more carbon atoms, preferably 1 to 18 carbon atoms) Shows a chain hydrocarbon group.)

The carbonate compound is preferably a carbonate,
It is at least one compound selected from bicarbonate, carbonate compound and sodium potassium carbonate. Among these, the counter ion of the carbonate or bicarbonate is preferably a monovalent alkali metal such as sodium, potassium or lithium or ammonium. Examples of the carbonate compound include methyl carbonate, ethyl carbonate, methyl ethyl carbonate, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, dibutyl carbonate, ethylene carbonate, lauryl phenyl carbonate, octyl phenyl carbonate and the like.

The boric acid compound is preferably at least one compound selected from borates and metaborates. The counter ion of these salts is preferably a monovalent alkali metal such as sodium, potassium, lithium and the like. The boron compound is preferably at least one compound selected from trimethyl borate, sodium boron hydride, and potassium boron hydride.

The silicate compound is preferably at least one compound selected from silicates, orthosilicates and aluminosilicates. The counter ion of these salts is preferably a monovalent alkali metal such as sodium, potassium, lithium and the like.

The silicon compound is preferably at least one selected from the group consisting of ethyl silicate and tetramethyl silicate.
Species of compound.

The amount of the coloring inhibitor added is 0.1 to 30% by weight, preferably 1 to 30% by weight, based on the fatty acid alkyl ester.
-10% by weight. If the amount is greater than this range, the amount of the coloring inhibitor mixed into the product may increase, and the performance of the surfactant may decrease. If the amount is less than 0.1% by weight, the effect of improving the color tone is hardly recognized. It is customary to mix the color inhibitor before the introduction of the sulfonating gas, since it is preferable from the viewpoint of operability.However, it is also possible to add and mix the color inhibitor after the sulfonating gas introduction step, ie, before the aging step. In addition, the progress of coloring during the aging step can be suppressed.

As the reaction method, a tank type reaction, a film reaction, a tube type gas-liquid multi-phase flow reaction, or the like is used. Therefore, as a sulfonation method, a thin film type sulfonation method,
Any sulfonation method such as a batch type sulfonation method can be adopted. The batch type sulfonation method is desirable in consideration of the color tone of the α-sulfofatty acid ester, but the thin film type sulfonation method is desirable in consideration of the cost at the production level.

As the sulfonating gas, SO ₃ gas, fuming sulfuric acid or the like is used. Preferably, SO ₃ gas is used, and usually an inert gas such as air or nitrogen having a concentration of 3
SO ₃ gas diluted to ３０30% by volume is used, and SO ₃ is used in an amount of 1.0 to 1.5 times, preferably 1.05 to 1.3 times, the mole of the raw material saturated fatty acid ester. If the molar ratio is less than 1.0 times, the sulfonation reaction does not proceed sufficiently. If the molar ratio exceeds 1.5 times, the sulfonation reaction becomes more intense, so that coloring due to local heat becomes remarkable, and the light-colored target product is It is not preferable in terms of obtaining.

The reaction temperature in the sulfonating gas introduction step may be a temperature at which the saturated fatty acid alkyl ester has fluidity. Generally, a temperature from the freezing point to a temperature 100 ° C. higher than the freezing point is applied. It is preferably from the freezing point to a temperature 70 ° C. higher than the freezing point. The reaction time at this time varies depending on the sulfonation method.
６０60 seconds, and about 10-120 minutes in the batch type sulfonation method.

In the aging step for promoting the SO ₃ elimination reaction from the bimolecular adduct, the reaction temperature is 70 to 12
0 ° C. is appropriate. When the temperature is lower than 70 ° C., the reaction does not proceed rapidly. When the temperature is higher than 120 ° C., the product is significantly colored. At this time, the reaction time is from 1 to 120 minutes.
After this aging step, a small amount of a lower alcohol may be added, if necessary, to carry out an esterification reaction to suppress the formation of the α-sulfofatty acid dialkali salt.

In order to use the α-sulfofatty acid alkyl ester formed after the aging step as a surfactant, a neutralization step with an alkali is required. This neutralization step is preferably performed when the reaction mixture of the α-sulfofatty acid alkyl ester and the alkali is in an acidic or weakly alkaline range, and when performed under strong alkalinity, the ester bond may be easily broken. There is. As the alkali used, for example, an alkali metal, an alkaline earth metal, ammonia, ethanolamine and the like are used.
Before or after this neutralization step, a bleaching step can be performed, if necessary.

The embodiments of the present invention are summarized as follows. (1) In the present invention, the coloring inhibitor may be present at least in the aging step, and is preferably 0.1 to 30% by weight based on the saturated fatty acid alkyl ester and the saturated fatty acid alkyl ester. After the mixture with the agent is brought into contact with SO ₃ gas at a reaction temperature equal to or higher than the freezing point of the saturated fatty acid alkyl ester, a ripening step of removing SO ₃ from the bimolecular adduct for a predetermined time is used.

(2) The coloring inhibitor used in the present invention is at least one selected from the group consisting of phosphoric acid compounds, organic phosphorus compounds, carbonate compounds, borate compounds, boron compounds, silicate compounds, and silicon compounds. Is a compound of The phosphoric acid compound is preferably a phosphate represented by the following general formula (II), (III) or (IV), a metaphosphate represented by the following general formula (V), or a general formula (VI) And at least one compound selected from the condensed phosphates represented by (VII). _{M 3 PO 4 ··· (II)} MH 2 PO 4 ··· (III) M 2 HPO 4 ··· (IV) MPO 3 ··· (V) M 5 P 3 O 10 ··· (VI) M ₃ P ₃ O ₉ (VII) (wherein M represents a monovalent alkali metal or ammonium)

The organic phosphorus compound is preferably at least one compound selected from the compounds represented by the following formulas (VIII) and (IX). (RO) ₃ P (VIII) R ₃ P (IX) (wherein R is hydrogen or a saturated or unsaturated straight-chain or side-chain having 1 or more carbon atoms, preferably 1 to 18 carbon atoms) Shows a hydrocarbon group.)

The carbonate compound is preferably a carbonate,
It is at least one compound selected from bicarbonate, carbonate compound and sodium potassium carbonate. Among these, the counter ion of the salt is preferably a monovalent alkali metal such as sodium, potassium or lithium or ammonium. As the carbonate compound, methyl carbonate, ethyl carbonate, methyl ethyl carbonate, dimethyl carbonate,
Examples include diethyl carbonate, dipropyl carbonate, ethylene carbonate, lauryl phenyl carbonate, octyl phenyl carbonate and the like.

The boric acid compound is preferably at least one boric acid compound selected from borates and metaborates. The counter ion of these salts is preferably a monovalent alkali metal such as sodium, potassium, lithium and the like. The boron compound is preferably at least one compound selected from trimethyl borate, sodium boron hydride, and potassium boron hydride.

The silicate compound is preferably at least one compound selected from silicates, orthosilicates and aluminosilicates. The counter ion of these salts is preferably a monovalent alkali metal such as sodium, potassium, lithium and the like. The silicon compound is at least one compound selected from ethyl silicate and tetramethyl silicate. (3) The addition amount of the coloring inhibitor is 0.1 to 30% by weight, more preferably the saturated fatty acid alkyl ester,
1 to 10% by weight.

(4) As the sulfonated gas, SO ₃ gas is preferable, and in particular, SO ₃ gas diluted to a concentration of 3 to 30% by volume with an inert gas such as air or nitrogen is preferably used. (5) The reaction temperature of the sulfonating gas introduction step is higher than the freezing point of the saturated fatty acid alkyl ester, preferably in the range from the freezing point to 100 ° C higher than the freezing point, more preferably in the range from the freezing point to 70 ° C higher than the freezing point. Will be (6) The reaction conditions in the aging step are preferably a temperature of 70 to 120 ° C. and a time of 1 to 120 minutes. (7) The iodine value of the raw material saturated fatty acid alkyl ester is preferably 0.5 or less, more preferably 0.1 or less.

(8) After the ripening step, an α-sulfofatty acid alkyl ester salt suitable as a surfactant is obtained by neutralization with an alkali under acidic or weak alkaline conditions. (9) The α-sulfofatty acid alkyl ester salt obtained by the production method of the present invention is produced through an aging step performed at least in the presence of a coloring inhibitor, preferably the saturated fatty acid alkyl ester and the saturated fatty acid alkyl a mixture of 0.1 to 30 wt% of the colored inhibitor against esters, after contacting with SO ₃ gas at a reaction temperature above the freezing point of the saturated fatty acid alkyl esters, the SO ₃ from bimolecular adduct It is produced through at least a ripening step of desorption.

[0042]

The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the technical scope of the present invention. << Experimental Examples 1-4, Comparative Example >> A coloring inhibitor as shown in Tables 2 to 6 was mixed with methyl myristate (raw material) having an iodine value of 0.13 (added to anything in Comparative Examples) Using a 300 ml glass reactor equipped with a jacket cooling and a stirrer and keeping the temperature at 80 ° C., 1.2 times mol of sulfuric anhydride gas diluted to 7% by volume with N ₂ gas (to the methyl myristate). Was introduced at a constant speed for 60 minutes. After the introduction, the mixture was stirred and aged for 30 minutes while maintaining the temperature at 85 ° C. to produce methyl α-sulfomyristate (α-sulfofatty acid alkyl ester).

In Tables 2 to 6, the amount of the coloring inhibitor added is shown as% by weight based on methyl myristate (raw material). The coloring inhibitors used in Experimental Examples 1 to 4 are compounds included in the following. Experimental Example 1: Phosphoric acid compound, organic phosphorus compound Experimental example 2: Carbonic acid compound Experimental example 3: Boric acid compound, boron compound Experimental example 4: Silicic acid compound, silicon compound

The conversion of the raw material methyl myristate was determined, and the color tone of the α-sulfofatty acid alkylmethyl was measured as follows. That is, after the aging step under the above conditions, a 5% by weight ethanol solution of α-sulfofatty acid alkylmethyl was dissolved in a 40 mm optical path length, No. 4
It was measured with a Kret photoelectric meter using a 2 blue filter. The results are shown in Tables 1 to 6. In Experimental Examples 1 to 4 according to the present invention, the effect of improving the color tone of the α-sulfofatty acid alkyl ester was observed as compared with Comparative Examples in which the coloring inhibitor was not added. The α-sulfofatty acid alkyl ester thus obtained was neutralized by a conventional method, and the color tone (5% by weight aqueous solution of AI) had the same value as before neutralization.

<< Experimental Example 5 >> In Experimental Example 5, a coloring inhibitor was added and mixed after the sulfonating gas introduction step, that is, before the aging step. Using a continuous thin film type sulfonation apparatus made of stainless steel, a mixed solution (raw material) of methyl laurate / methyl myristate / methyl palmitate (mixing weight ratio: 3/6/1) having an iodine value of 0.08 was used.
The sulfonating gas introduction step was performed at a reaction temperature of 80 ° C. using SO ₃ gas diluted to 5% by volume with dry air.
This reaction product was sampled in a 300 ml glass container,
Sodium phosphate (phosphate compound) was added in an amount of 5% by weight based on the raw material equivalent of the sampled reactant, and 85%
The aging step was performed at 60 ° C. for 60 minutes to produce an α-sulfofatty acid alkyl ester.

As a result, the reaction rate of the raw material was 96.0%,
The color tone measured in the same manner as in Experimental Examples 1 to 4 was 840. The α-sulfofatty acid alkyl ester thus obtained was neutralized by a conventional method, and the color tone (5% by weight aqueous solution of AI) had the same value as before neutralization.
Therefore, it was confirmed that the effect of the coloring inhibitor can be obtained even when the coloring inhibitor is added and mixed after the sulfonating gas introduction step, that is, before the aging step.

[0047]

[Table 1]

[0048]

[Table 2]

[0049]

[Table 3]

[0050]

[Table 4]

[0051]

[Table 5]

[0052]

[Table 6]

[0053]

According to the present invention, when an α-sulfofatty acid alkyl ester salt is produced from a saturated fatty acid alkyl ester, at least the aging step is carried out in the presence of a coloring inhibitor selected from a specific compound, so that it becomes white. Close pale α-
A sulfo fatty acid alkyl ester salt is obtained. For this reason, the bleaching step can be simplified or omitted as necessary, the generation of by-products can be suppressed, and the quality can be improved and the cost can be reduced.

Claims (4)

[Claims] 1. The following general formula (I): R ₁ CH ₂ COOR ₂ ... (I) (wherein, R ₁ represents an alkyl group having 6 to 24 carbon atoms, and R ₂ represents 1 to 6 carbon atoms) and saturated fatty acid alkyl ester represented by the alkyl represents a group) of a sulfonating gas introduction step of contacting a sulfonating gas to desorb SO ₃ from SO ₃ bimolecular adduct after the sulfonating gas introducing step A method for producing an α-sulfofatty acid alkyl ester salt having a ripening step, wherein at least the ripening step includes a phosphoric acid compound, an organic phosphorus compound, a carbonate compound, a borate compound,
A process for producing a light-color α-sulfofatty acid alkyl ester salt, which is carried out in the presence of at least one compound selected from the group consisting of a boron compound, a silicate compound and a silicon compound. 2. The method for producing an α-sulfofatty acid alkyl ester salt according to claim 1, wherein the phosphoric acid compound is represented by the following general formula (II), (III),
At least one compound selected from the group consisting of a phosphate represented by (IV), a metaphosphate represented by the following general formula (V), and a condensed phosphate represented by the following general formulas (VI) and (VII) _{, M 3 PO 4 ··· (II} ) MH 2 PO 4 ··· (III) M 2 HPO 4 ··· (IV) MPO 3 ··· (V) M 5 P 3 O 10 ··· (VI _{) M 3 P 3 O 9 ···} (VII) (M in the formula represents a monovalent alkali metal or ammonium.) the organic phosphorus compound is represented by the following general formula (VIII), (I
(RO) ₃ P ... (VIII) R ₃ P ... (IX) (where R is hydrogen or a saturated group having 1 or more carbon atoms) Or an unsaturated straight-chain or side-chain hydrocarbon group.) The carbonate compound is at least one compound selected from a carbonate, a hydrogen carbonate, a carbonate compound, and sodium potassium carbonate. , Borate, metaborate, at least one compound selected from the group consisting of trimethyl borate, sodium boron hydride, and potassium boron hydride. The silicate compound is at least one compound selected from silicate, orthosilicate, and aluminosilicate, and the silicon compound is ethyl silicate. The process of light-colored α- sulfofatty acid alkyl ester salts, characterized in that at least one compound selected from silicic acid tetramethyl. 3. The following general formula (I): R ₁ CH ₂ COOR ₂ ... (I) wherein R ₁ represents an alkyl group having 6 to 24 carbon atoms, and R ₂ represents 1 to 6 carbon atoms. and saturated fatty acid alkyl ester represented by the alkyl represents a group) of a sulfonating gas introduction step of contacting a sulfonating gas to desorb SO ₃ from SO ₃ bimolecular adduct after the sulfonating gas introducing step An α-sulfofatty acid alkyl ester salt produced through at least an aging step, wherein at least the aging step includes a phosphoric acid compound, an organic phosphorus compound, a carbonic acid compound, a boric acid compound,
A light-colored [alpha] -sulfofatty acid alkyl ester salt produced by carrying out in the presence of at least one compound selected from the group consisting of a boron compound, a silicic acid compound, and a silicon compound. 4. The α-sulfofatty acid alkyl ester salt according to claim 3, wherein the phosphoric acid compound is represented by the following general formula (II), (III),
At least one compound selected from the group consisting of a phosphate represented by (IV), a metaphosphate represented by the following general formula (V), and a condensed phosphate represented by the following general formulas (VI) and (VII) _{, M 3 PO 4 ··· (II} ) MH 2 PO 4 ··· (III) M 2 HPO 4 ··· (IV) MPO 3 ··· (V) M 5 P 3 O 10 ··· (VI _{) M 3 P 3 O 9 ···} (VII) (M in the formula represents a monovalent alkali metal or ammonium.) the organic phosphorus compound is represented by the following general formula (VIII), (I
(RO) ₃ P ... (VIII) R ₃ P ... (IX) (where R is hydrogen or a saturated group having 1 or more carbon atoms) Or an unsaturated straight-chain or side-chain hydrocarbon group.) The carbonate compound is at least one compound selected from a carbonate, a hydrogen carbonate, a carbonate compound, and sodium potassium carbonate. , Borate, metaborate, at least one compound selected from the group consisting of trimethyl borate, sodium boron hydride, and potassium boron hydride. The silicate compound is at least one compound selected from silicate, orthosilicate, and aluminosilicate, and the silicon compound is ethyl silicate. , Pale α- sulfofatty acid alkyl ester salts, characterized in that at least one compound selected from silicic acid tetramethyl.