KR20040059032A - Method for preparing of alkyl poly glycosides - Google Patents

Abstract

The present invention relates to a method for producing an alkyl polyglycoside, in particular, by adding a chelating agent to the bleaching step to remove metal ions to inhibit the decomposition of the peroxide in the alkyl polyglycoside by the metal ion, and to reduce the residual period of the peroxide. The present invention relates to a method for preparing alkylpolyglycoside, which is not only excellent in color stability and transparency, but also significantly improved in storage stability by suppressing yellowing of alkylpolyglycoside.

Description

Method for producing alkyl polyglycoside {METHOD FOR PREPARING OF ALKYL POLY GLYCOSIDES}

The present invention relates to a method for producing an alkylpolyglycoside, and more particularly, to inhibit the decomposition of peroxide in the alkylpolyglycoside by metal ions and to increase the residual period of the peroxide, thereby preventing yellowing of the alkylpolyglycoside. The present invention relates to a method for preparing alkylpolyglycoside, which is inhibited and has excellent chromatographic stability and transparency, and at the same time, remarkably improved storage stability.

Alkyl polyglycosides (APGs) are obtained by reacting a carbohydrate-based raw material such as glucose with excess higher fatty alcohols in the presence of an acid catalyst, neutralizing the acid catalyst with alkali and then removing the unreacted fatty alcohols remaining in the reactants. Nonionic surfactants.

In addition, the alkyl polyglycoside-based nonionic surfactant has an advantage of being able to greatly reduce the problem of water pollution even when used as a detergent due to its excellent biodegradability and low skin irritation by using natural raw materials.

Regarding the method for preparing the alkyl polyglycoside as described above, European Patent No. 301,298, European Patent No. 357,969, International Patent No. 90-194,262, and International Patent No. 90-218,084 are methyl alcohol, ethyl alcohol, or butyl. Lower alcohols such as alcohols are reacted with glucose in the presence of an acid catalyst such as sulfuric acid or hydrochloric acid to prepare lower alkylpolyglycosides, and then higher alkylols having 8 to 22 carbon atoms are added thereto to prepare higher alkylpolyglycosides having excellent detergency. A method is disclosed. However, the above methods require an apparatus for removing and recovering the lower alcohol forming the reaction solvent and the reaction intermediate, and in particular, the lower alcohol is usually used about 10 times with respect to glucose. Therefore, in the relevant industry, a method for producing alkyl polyglycosides by directly reacting higher fatty alcohols with glucose described in European Patent Nos. 387,913 and 388,857 is mainly used. However, according to these methods, there is a problem that the alkylpolyglycoside is discolored due to the high temperature when the unreacted alcohol is recovered after the reaction.

In the preparation of the alkylpolyglycoside, an excess of alkali is used in the neutralization step, and the monopolysaccharide (mono saccharide) and the like deteriorate due to the high temperature for the recovery of the unreacted alcohol, thereby causing the alkylpolyglycoside to turn yellow. While neutralization can reduce the degree of color development by accurate neutralization, it is impossible to suppress it completely. Therefore, if it has already been developed, it can only be limited to application to high-quality products such as household detergents without going through the bleaching process in the final stage. none.

In view of the above, each manufacturer is carrying out a process of bleaching using a peroxide-based bleach such as hydrogen peroxide (H ₂ O ₂ ) as a post-treatment for producing alkyl polyglycosides. However, it is also difficult to produce satisfactory alkylpolyglycosides in terms of chromaticity, and in particular, due to low color storage stability, color reversion occurs during storage period after bleaching of alkylpolyglycosides. There is a problem of deterioration. Accordingly, there is a problem that the alkylpolyglycoside must be re-bleached before the alkylpolyglycoside is added to the detergent.

Therefore, there is a need for further research on a method for stably maintaining the chromaticity of the alkylpolyglycoside for a long time.

In order to solve the problems of the prior art as described above, the present invention suppresses the acceleration of decomposition of the peroxide in the alkyl polyglycoside by metal ions, and increases the remaining period of the peroxide to suppress the yellowing phenomenon of the alkylpolyglycoside, resulting in chromaticity stability. And to provide a process for producing alkylpolyglycosides which is not only excellent in transparency but also significantly improved in storage stability.

In order to achieve the above object, the present invention provides a method for producing an alkyl glycoside,

a) reacting the aliphatic alcohol with glucose under an acid catalyst;

b) neutralizing by adding a neutralizing agent to the reaction of step a);

c) alkyl by distilling the unreacted aliphatic alcohol from the reactant of step b)

Concentrating the polyglycoside;

d) diluting the concentrated alkylpolyglycoside concentrate of step c).

step; And

e) a base, a chelating agent, in the diluted alkylpolyglycoside of step d),

And bleaching by adding peroxide

It provides a method for producing an alkylpolyglycoside comprising a.

Hereinafter, the present invention will be described in detail.

The present inventors have been studying a method for stably maintaining the chromaticity of the alkylpolyglycoside for a long time, and as a result of adding a chelating agent to the bleaching step to remove the metal ions, suppressing the acceleration of decomposition of the peroxide by the metal ions, By increasing the residual period of the peroxide in the polyglycoside to suppress the yellowing phenomenon of the alkylpolyglycoside, it was confirmed that not only the color stability and transparency is excellent, but also the storage stability is remarkably improved, and based on this, the present invention was completed.

After bleaching using peroxide-based bleach such as hydrogen peroxide as a post-treatment agent for the purpose of improving the chromaticity of the alkylpolyglycoside, when a small amount of peroxide is left in the bleached alkylpolyglycoside at the level of several tens to several hundred ppm, residual peroxide Is slowly decomposed into water and oxygen over several weeks to several months, but yellowing does not proceed when the peroxide is less than 10 ppm, and yellowing gradually progresses after the peroxide is completely decomposed. The yellowing phenomenon accelerates more when the pH is low and when the storage temperature is high.

Therefore, in order to suppress the yellowing of the bleached alkyl polyglycoside and to improve color stability, a small amount of peroxide is added to the alkylpolyglycoside after decolorization so as to maintain a long period of peroxide remaining in the alkylpolyglycoside. In addition, the degradation rate of the added peroxide during the storage period of the alkylpolyglycoside should be as low as possible. The decomposition rate of the peroxide is greatly affected by the impurity content such as storage temperature, pH, and metal ions of the alkylpolyglycoside solution, and the higher the storage temperature, the higher the pH, and the higher the metal ion content, the higher the decomposition rate. do.

Among them, impurities such as metal ions are contained in the raw material or dissolved in the product due to contamination of the dilution process water and corrosion of the equipment in the alkyl polyglycoside manufacturing process. In addition, since the decomposition of the peroxide is accelerated rapidly, metal ions must be removed in order to suppress decomposition of the peroxide and to improve chromatic stability of the alkylpolyglycoside.

Thus, the present invention comprises the steps of reacting an aliphatic alcohol with a carbohydrate and an acid catalyst; Neutralizing the reactants by adding a neutralizing agent; Distilling the unreacted aliphatic alcohol in the reactant to concentrate the alkylpolyglycoside; Diluting the concentrated alkylpolyglycoside concentrate; And bleaching by adding a base and a peroxide to the diluted alkylpolyglycoside, wherein the chelating agent is added to the bleaching step to remove metal ions.

The chelating agent used in the present invention serves to remove metal ions such as iron and copper dissolved in the alkylpolyglycoside, thereby preventing the decomposition of the peroxide by the metal ions, and remaining of the peroxide in the alkylpolyglycoside. By increasing the period of time, the yellowing phenomenon of the alkylpolyglycoside is suppressed to improve chromaticity stability, transparency, and storage stability.

The chelating agent is a phosphate chelate such as pyrophosphoric acid, mono / di / polyphosphoric acid, 1-hydroxyethylidene-1,1-diphosphonic acid (CODEX 661, 1-hydroxyethylidene-1,1-diphosphonic acid) The agent and its salt, or organic chelating agent, such as ethylenediamine triacetic acid (EDTA), nitrilo triacetic acid (NTA), cyclohexanediamine tetraacetic acid (CyDTA), its salt, etc. can be used.

The chelating agent is preferably included in 20 to 10,000 ppm compared to the alkylpolyglycoside concentrate, more preferably included in 50 to 5,000 ppm, most preferably included in 100 to 2,000 ppm. If the content is less than 20 ppm there is little effect by the chelating agent, when the content exceeds 10,000 ppm there is a problem that the purity of the product is lowered due to the excessively added chelating agent.

The manufacturing method of the present invention will be described in detail as follows.

a) aliphatic alcohol and carbohydrate reactions

This step is to react the aliphatic alcohol with carbohydrate and acid catalyst.

The aliphatic alcohol is preferably to use a higher aliphatic alcohol having 6 to 22 carbon atoms, the content is preferably included in a molar ratio of 1 to 10 per mole of the carbohydrate, more preferably in a molar ratio of 2.5 to 5 Will be.

The carbohydrate is preferably glucose.

The acid catalyst is preferably used ρ-TSA (ρ-toluenesulfonic acid), the content is preferably included in a molar ratio of 0.001 to 0.01 per mol of carbohydrates.

The reaction is preferably performed for about 1 to 10 hours at an absolute pressure of 10 to 100 torr at 110 to 125 ℃. After the reaction as described above, it is preferable to carry out the reaction so that the unreacted carbohydrate-based reactant is at most 3%.

b) neutralization

This step is to neutralize by adding a neutralizing agent to the reactant.

Preferably, the reactants have a residual moisture content of at most 1000 ppm, more preferably at most 500 ppm.

The neutralizing agent may use sodium hydroxide, magnesium oxide and the like, in particular magnesium oxide having a specific surface area of at least 30 m 2 / g, preferably at least 50 m 2 / g and a water content of at most 5%, preferably at most 3%. Preference is given to using.

The neutralizing agent is preferably added in the form of fine powder, the content of which is preferably included in 1.0 ~ 2.0 mol / ρ-TSA mol, more preferably 1.20 ~ 1.80 mol / ρ-TSA mol.

The neutralization may be carried out by stirring for 20 to 60 minutes at 60-120 ° C under normal pressure or vacuum if necessary, and neutralizes the pH of the reaction solution to 7.0-8.0.

c) distillation

This step is to distill the unreacted aliphatic alcohol in the neutralized reactant to concentrate the alkylpolyglycoside.

The distillation is carried out at high temperature and high vacuum, it is preferable to distill so that the unreacted aliphatic alcohol is at most 2%, preferably at most 1%.

d) dilution

This step is to dilute the alkylpolyglycoside concentrate.

At this time, it is preferable to add water, an organic solvent, etc. to the alkyl polyglycoside concentrate to dilute the water content to 30 to 70%.

e) bleaching

This step is a step of bleaching by adding a base, a chelating agent, and a peroxide to the diluted alkyl polyglycoside, in particular, a step of removing metal ions by adding a chelating agent.

The chelating agent can be adjusted according to the metal content contained in the alkylpolyglycoside, but preferably 20 to 10,000 ppm, more preferably 50 to 5,000 ppm, most preferably 100 to the alkylpolyglycoside concentrate 2,000 ppm is included.

The base is preferably used sodium hydroxide, the content is preferably contained in 0.5 to 5.0 parts by weight relative to the alkylpolyglycoside concentrate, more preferably 0.7 to 3.0 parts by weight, most preferably 0.9 to 1.5 It is included in parts by weight.

The peroxide is preferably included in 0.2 to 3.0 parts by weight relative to the alkyl polyglycoside concentrate, more preferably 0.5 to 2.5 parts by weight, most preferably 0.7 to 2.0 parts by weight.

In particular, in this step, a base is added to the diluted alkyl polyglycoside and stirred for 10 to 30 minutes to adjust the pH to 10 to 11, and then a chelating agent is added thereto, stirred for 30 minutes to remove metal ions, and then peroxide. It is preferable to add and bleach for 1 to 10 hours at a temperature of 70 ~ 110 ℃.

After the bleaching, the peroxide is preferably added so that the content of the peroxide in the decolorized alkyl polyglycoside is 20 to 500 ppm, and more preferably, the peroxide is added so that the content of the peroxide is 50 to 200 ppm. To put it.

The preparation method of the present invention comprising the steps as described above can suppress the acceleration of decomposition of the peroxide in the alkyl polyglycoside, increase the residual period of the peroxide to suppress the yellowing phenomenon of the alkylpolyglycoside to be excellent in color stability and transparency At the same time, there is an effect that the storage stability can be significantly improved.

Hereinafter, preferred examples are provided to help understanding of the present invention, but the following examples are merely to illustrate the present invention, and the scope of the present invention is not limited to the following examples.

EXAMPLE

Example 1

5.3 g of 30% sodium hydroxide was added to 400.0 g of a 50% alkylpolyglycoside solution having a chromaticity of G # 7, a metal ion content of 5 ppm such as iron, and a pH of 8.2. 0.04 g of ethylenediaminetriacetic acid (EDTA) was added thereto as a chelating agent, and 8.6 g of 35% hydrogen peroxide was added thereto, stirred at 90 to 95 ° C for 30 minutes, and bleached to obtain an alkylpolyglycoside solution having a chromaticity of APHA 100. It was. After bleaching, the temperature of the alkylpolyglycoside solution was lowered to 40 ° C., and 0.035 g of 35% hydrogen peroxide was further added, followed by uniformly stirring.

Example 2

5.3 g of 30% sodium hydroxide was added to 400.0 g of a 50% alkylpolyglycoside solution having a chromaticity of G # 7, a metal ion content of 5 ppm such as iron, and a pH of 8.2. To this was added 0.04 g of 1-hydroxyethylidene-1,1-diphosphonic acid (CODEX 661, 1-hydroxyethylidene-1,1-diphosphonic acid, Excel) as a chelating agent, followed by 35% hydrogen peroxide 8.6 g was added, stirred at 90-95 ° C. for 30 minutes, and bleached to obtain an alkylpolyglycoside solution having a chromaticity of APHA 100. After bleaching, the temperature of the alkylpolyglycoside solution was lowered to 40 ° C., and 0.035 g of 35% hydrogen peroxide was further added, followed by uniformly stirring.

Comparative Example 1

To 400.0 g of a 50% alkylpolyglycoside solution with a chromaticity of G # 7 and a metal ion content of 5 ppm, such as iron, and a pH of 8.2, 5.3 g of 30% sodium hydroxide and 8.6 g of 35% hydrogen peroxide were added. Stirring and bleaching at ˜95 ° C. for 4 hours gave 412.5 g of an alkylpolyglycoside solution with a chromaticity of APHA 110 and a residual hydrogen peroxide content of 0 ppm.

Comparative Example 2

To 400.0 g of a 50% alkylpolyglycoside solution containing 10 ppm of metal ions such as G # 7 and 10 ppm of iron and pH pH 8.2, 5.3 g of 30% sodium hydroxide and 8.6 g of 35% hydrogen peroxide were added. Stirring and bleaching at ˜95 ° C. for 4 hours gave an alkylpolyglycoside solution with a chromaticity of APHA 150 and a residual hydrogen peroxide content of 0 ppm.

Comparative Example 3

To 400.0 g of a 50% alkylpolyglycoside solution with a chromaticity of G # 7 and a metal ion content of 5 ppm, such as iron, and a pH of 8.2, 5.3 g of 30% sodium hydroxide and 8.6 g of 35% hydrogen peroxide were added. Stirring and bleaching at ˜95 ° C. for 4 hours yielded an alkylpolyglycoside solution of color APHA 110. After bleaching, the temperature of the alkylpolyglycoside solution was lowered to 40 ° C., and 0.035 g of 35% hydrogen peroxide was further added, followed by uniformly stirring.

Comparative Example 3

To 400.0 g of a 50% alkylpolyglycoside solution with a chromaticity of G # 7 and a metal ion content of 5 ppm, such as iron, and a pH of 8.2, 5.3 g of 30% sodium hydroxide and 8.6 g of 35% hydrogen peroxide were added. Stirring and bleaching at ˜95 ° C. for 4 hours yielded an alkylpolyglycoside solution of color APHA 110. After bleaching, the temperature of the alkylpolyglycoside solution was lowered to 40 ° C., and 0.07 g of 35% hydrogen peroxide was further added, followed by uniformly stirring.

Experimental Example 1

The alkyl polyglycoside solution prepared in Examples 1 or 2 and Comparative Examples 1 to 4 was stored at 50 ° C. to observe the color change, and the yellowing phenomenon occurred, and the chromaticity after 6 months of storage was measured. It is shown in Table 1 below.

division Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Metal ion content before bleaching (ppm) 5 5 5 10 5 5 Chromaticity after Decolorization (APHA) 100 100 110 150 110 110 Additional amount of hydrogen peroxide (g) 0.035 0.035 - - 0.035 0.07 Chelating Agent Dosage (g) EDTA 0.04 - - - - - CODEX 661 - 0.04 - - - - When yellowing occurs After 140 days In 145 days 10 days later 10 days later 25 days later 35 days later Chromaticity (APHA) after 6 months storage 150 140 420 470 390 370

Through Table 1, Example 1 or 2 prepared by adding a chelating agent to the bleaching step in accordance with the present invention to remove the metal ions to inhibit the yellowing phenomenon of the alkyl polyglycoside compared to Comparative Examples 1 to 4 It was confirmed that the stability and storage stability was excellent.

According to the preparation method of the present invention, it is possible to suppress the acceleration of decomposition of the peroxide in the alkyl polyglycoside and to increase the residual period of the peroxide to suppress the yellowing phenomenon of the alkylpolyglycoside, thereby providing excellent color stability and transparency, and at the same time storage stability. There is an effect of producing an alkylpolyglycoside which can be remarkably improved.

Claims (6)

In the method for producing an alkylglycoside, a) reacting the aliphatic alcohol with glucose under an acid catalyst; b) neutralizing by adding a neutralizing agent to the reaction of step a); c) alkyl by distilling the unreacted aliphatic alcohol from the reactant of step b) Concentrating the polyglycoside; d) diluting the concentrated alkylpolyglycoside concentrate of step c). step; And e) a base, a chelating agent, in the diluted alkylpolyglycoside of step d), And bleaching by adding peroxide Method for producing an alkylpolyglycoside comprising a. The method of claim 1, The chelating agent of step e) is pyrophosphoric acid, mono / di / polyphosphoric acid, 1-hydroxyethylidene-1,1-diphosphonic acid (CODEX 661, 1-hydroxyethylidene-1,1-diphosphonic acid), A method for producing an alkylpolyglycoside selected from at least one selected from the group consisting of ethylenediaminetriacetic acid (EDTA), nitrilotriacetic acid (NTA), and cyclohexanediaminetetraacetic acid (CyDTA). The method of claim 1, Method for preparing an alkylpolyglycoside containing the chelating agent of step e) 20 to 10,000 ppm compared to the alkylpolyglycoside concentrate. The method of claim 1, Method of preparing an alkylpolyglycoside containing the base of step e) is 0.5 to 5.0 parts by weight relative to the alkylpolyglycoside concentrate. The method of claim 1, Method of producing an alkylpolyglycoside containing the peroxide of step e) 0.2 to 3.0 parts by weight relative to the alkylpolyglycoside concentrate. The method of claim 1, Method of producing an alkylpolyglycoside further added to the peroxide so that the content of the peroxide in the alkylpolyglycoside after the bleaching step of e) to 20 to 500 ppm.