KR0138203B1 - Process for the preparation of alkyl polyglucoside - Google Patents

Abstract

The present invention relates to a process for the preparation of higher alkylpolyglucosides represented by the following general formula (I), wherein glucose and higher fatty alcohols are reacted in the presence of an acid catalyst under reduced pressure.

Wherein R is a linear or branched alkyl or alkenyl group having 8 to 22 carbon atoms, and n is 1 to 10 as the average glucose polymerization degree.

Description

Process for preparing higher alkyl polyglucoside

The present invention relates to a process for preparing higher alkylpolyglucosides which are natural nonionic surfactants. More specifically, the present invention relates to a method for preparing higher alkylpolyglucosides having a shorter reaction time and a simpler process by reacting monosaccharides with higher fatty alcohols by adding a small amount of lower alcohols and glycols.

In general, since the conventional surfactants pollute or destroy the environment and exhibit high irritation to the human body, these problems are relatively large with increasing demand. In order to solve this problem, there is a growing interest in surfactants having a natural surfactant and hypoallergenic.

The production of this natural higher alkylpolyglucoside has been known by the method of Fischer (Fisher) prepared by reacting glucose and lower alcohol in the presence of an acid catalyst, but this method has a disadvantage that does not apply to higher alcohol. In addition, the hydroxyl group of glucose is acetylated using the method of Koenigs-Knorr, and then phosphated to be brominated at the alpha carbon position and reacted with a higher alcohol under a Lewis acid catalyst to hexyl, octyl, decyl, dodecyl. To learn how to beta glucosidize, Rockwell (Noleer and Rockwell: American Chemical Society, J. Am. Chem. Soc. 60, 2076, 1938), but the process has gone through many complex steps and advanced reagents. There is a disadvantage to be used, it is difficult to use industrially because of high manufacturing cost.

In US Pat. No. 3,598,865, Baak et al. Disclose a process for preparing higher alkylpolyglucosides by first preparing lower alkylpolyglucosides with butanol under sulfuric acid catalysts, adding higher alcohols thereto, followed by exchange glucosylation. It was. As a similar method, U.S. Patent No. 3,707,535 discloses an exchange glucosylation method using methoxy, ethanol, ethoxy ethanol, ethoxy propanol, butoxy ethanol and the like. However, the preparation of these patents requires a device for removing and recovering the lower alkanols forming the reaction solvent and the reaction intermediate, and at least 1 to 10 times lower alcohol than the glucose is used. In addition, lower alcohols such as butanol form an azeotropy with water to remove water generated during the reaction. However, methoxy ethanol or glycols cannot remove water, and solvents such as benzene, toluene, and hexane are added to remove water. The glycols have a high boiling point and are not easy to remove.

In Japanese Patent Application Laid-Open No. 62-99390, Hidaka et al. Use acetals and carbonic acid diesters to remove water produced during the reaction, and the reaction solvent uses glucose and higher alcohol in the presence of dimethyl sulfoxide or dimethylformamide. Although a method of preparing higher alkylpolyglucoside by reaction has been disclosed, this method is also difficult to remove because dimethyl sulfoxide or dimethylformamide used as a solvent has a very high boiling point.

In US Pat. No. 3,839,318, Richard et al. Prepared higher alkylpolyglucosides during the reaction of glucose and higher alcohols directly under sulfuric acid catalysts without the use of solvents. Toluene or the like is added to remove water by using these substances to form an azeotropic point with water.

In European Patent No. 387,913 and European Patent No. 388,857, Hiroki and Akira produced higher alkylpolyglucosides directly using glucose and higher fatty alcohols, but this method eliminates unreacted glucose because of the large amount of unreacted glucose. There is a disadvantage in the process of distilling excess fatty alcohol through a filtration process.

Thus far, the preparation of higher alkylpolyglucosides generally uses glucose and higher alcohol, but the reaction under a homogeneous system is difficult because glucose is easily dissolved in water and hardly dissolved in alcohols or nonpolar solvents.

Therefore, the first step is to prepare lower alkylpolyglucoside using lower alcohols, glycols, etc., and then use a method of exchange glucosylation to remove lower alcohol by adding a higher alcohol and a solvent without using glucose and higher alcohol. A method of preparing a higher alkyl polyglucoside by using a reaction solvent such as dimethyl sulfoxide or the like is known. The reaction is performed using benzene, toluene, nucleic acid, etc. to remove water generated during the reaction. It is removing the water generated.

However, these conventional preparations require the recovery, purification and regeneration of lower alcohols and glycols used as intermediates in exchange glucosylation reactions, and the dimethyl sulfoxides used as reaction solvents in the direct method. Low alcohols, glycols, solvents, etc., by using a non-polar solvent such as benzene, toluene, etc. to remove the water generated during the reaction or by direct filtration to remove unreacted glucose. In addition to the high equipment costs such as recovery, purification and filtration of the petroleum, low alkyl glucosides and unreacted glucoses are large and the reaction time is very long, requiring a large operating cost.

Accordingly, an object of the present invention is to solve the above-mentioned problems of the prior art, and in the preparation of higher alkylpolyglucosides, unreacted glucose by adding a small amount of lower alcohols and glycols to glucose and higher fatty alcohols in the presence of an acid catalyst. The present invention provides a method for producing a high-quality alkylpolyglucoside of high quality, which has a significantly low amount, is very easy to remove water generated during the reaction, a reaction time is very short, and a simple process.

That is, the present invention relates to a method for preparing higher alkylpolyglucoside represented by the following general formula (I), characterized in that glucose and higher fatty alcohol are reacted in the presence of an acid catalyst under reduced pressure.

Wherein R is a linear or branched alkyl, alkenyl, or alcoholalkyl alkyl group having 8 to 22 carbon atoms and n is 1 to 10 as the average glucose degree of polymerization.

Hereinafter, the present invention will be described in detail.

First, the acid catalyst, higher fatty alcohols having 8 to 22 carbon atoms, and glucose are put into a reactor and heated. Water produced during the reaction is removed under reduced pressure, and lower alcohols and glycols are added at the beginning or after the reaction has proceeded. Upon completion of the reaction, it becomes a slightly yellow transparent phase, at which time the reactor is cooled, neutralized with alkali, and distilled under reduced pressure of higher fatty alcohol to obtain higher alkylpolyglucoside of formula (I).

Alcohols used in the present invention are saturated, unsaturated, linear or branched higher fatty alcohols having 8 to 22 carbon atoms, preferably octyl alcohol, nonyl alcohol, decyl alcohol, undecyl alcohol, dodecyl alcohol, tridecyl Alcohol, tetradecyl alcohol, pentadecyl alcohol, hexadecyl alcohol, hexadecenyl alcohol, heptadecyl alcohol, hexadecenyl alcohol, heptadecyl alcohol, octadecyl alcohol, octadecenyl alcohol, nonadecyl alcohol, eicosyl alcohol, hen Eicosyl alcohol, docosyl alcohol or mixed fatty alcohols thereof are used. The amount of alcohol used is 0.5 to 12 times the weight ratio than the amount of glucose, more preferably 1 to 7 times the weight ratio. If it is less than this ratio, a large amount of side reaction materials are produced, and if too large, a large amount of time is required for distillation under reduced pressure.

As the acid catalyst, inorganic acids and organic acids such as sulfuric acid, phosphoric acid, hydrochloric acid, hydroxyl and paratoluene sulfonic acid are used. The addition amount of the catalyst uses 0.001 to 0.5% (weight ratio) of the total weight of the reactants, more preferably 0.01 to 0.1% (weight ratio). If the acid catalyst is used less than 0.001%, the reaction rate is slow, and the yield is not good.

In the present invention, lower alcohols, glycols and glycol ethers can be used as reaction aids.

Lower alcohols used as reaction aids include butanol, pentanol, heptanol, hexanol, octanol, isooctanol, 2-ethylhexanol, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, butylene Glycol, hexylene glycol, ethylene di (tri, poly) glycol, propylene di (tri, poly) glycol, methoxy mono (di, tri, poly) ethylene glycol monoether, ethoxy mono (di, tri, poly) ethylene Glycol monoether, propoxy mono (di, tri, poly) ethylene glycol monoether, butoxy mono (di, tri, poly) ethylene glycol monoether and the like.

The amount of the reaction aid may be 0 to 500% (molar ratio) of the amount of glucose used in the reaction, but preferably 1.2 to 20% (molar ratio). If the amount of the reaction aid is used in a large amount, the amount of lower glucoside is produced, which is not good for the quality of the product. If the amount is used in a small amount, the amount of unreacted glucose is increased.

The reaction according to the present invention is carried out in the range of the reaction temperature of 80 to 170 ℃ and reduced pressure vacuum 10 to 400mmHg, more preferably in the range of the reaction temperature 100 to 140 ℃ and reduced pressure vacuum 20 to 200mmHg. If the reaction temperature is too low, the reaction rate is slow, so more reaction time is required. If the reaction temperature is too high, it is not easy to remove the water generated during the reaction. As it needs to be lowered, a freezer is required, which increases the process weight.

Hereinafter, although this invention is demonstrated concretely based on an Example, it should not be understood that the technical scope of this invention is limited to these Examples.

Example 1

In a three-necked flask equipped with a mechanical stirrer, a thermometer, and an oil water separator, 500 g of decyl alcohol, 0.5 g of paratoluene sulfonic acid, 170 g of glucose, and 20 g of butanol were added and heated to 120 to 130 ° C. At this time, the vacuum degree in the reactor is maintained at 50 to 100mmHg and refluxed under reduced pressure for about 2 hours to remove the water produced during the reaction. As the reaction proceeds gradually, the reactants gradually become a pale yellow transparent liquid. After the reaction is completed, the reaction is cooled to 100 ° C. or lower, and 0.25 g of caustic soda is dissolved in 0.5 cc of water, followed by neutralization. Excess fatty alcohol 398 g was removed by distillation under reduced pressure at 1 mmHg or less to obtain 254.5 g of a yellow hard solid having an average glucose degree of polymerization (n) of 1.5.

The composition of the final product is as follows.

Decyl polyglucoside: 98.0% (weight ratio) or more

Glucose: 0.4% (weight ratio) or less

Decyl alcohol: 0.8% or less

Others: 0.8% or less

※ Average glucose polymerization degree (n) calculation method

Example 2

In a three-necked flask equipped with a mechanical stirrer, a thermometer, and an oil water separator, 500 g of decyl alcohol, 0.5 g of sulfuric acid, 190 g of glucose, and 20 g of butanol were added and heated to 120 to 130 ° C. At this time, the vacuum degree in the reactor is maintained at 50 to 100mmHg and refluxed under reduced pressure for about 2 hours to remove the water produced during the reaction.

As the reaction proceeds gradually, the reactants gradually become a pale yellow transparent liquid. After the reaction is completed, the reaction is cooled to 100 ° C. or lower, and 0.75 g of sodium carbonate is dissolved in 3 cc of water, followed by neutralization. Excess fatty alcohol 396g was removed by distillation under reduced pressure at 1 mmHg or less to obtain 277 g of a yellow hard solid having an average glucose degree of polymerization (n) of 1.6.

The composition of the final product is as follows.

Decyl polyglucoside: 98.5% or more

Glucose: 0.4% (weight ratio) or less

Decyl alcohol: 0.7% (weight ratio) or less

Others: 0.4% or less

Example 3

In a three-necked flask equipped with a mechanical stirrer, a thermometer, and an oil / water separator, 500 g of decyl alcohol, 0.5 g of paratoluene sulfonic acid, 290 g of glucose, and 20 g of butanol were added and heated to 120 to 130 ° C. At this time, the vacuum degree in the reactor is maintained at 30 to 60mmHg and refluxed under reduced pressure for about 2 hours to remove the water generated during the reaction. As the reaction proceeds gradually, the reactants gradually become a pale yellow transparent liquid. After the reaction is completed, the reaction product is cooled to 100 ° C. or lower, and 0.5 g of sodium carbonate is dissolved in 2 cc of water, followed by neutralization. Excess fatty alcohol 396 g was removed by distillation under reduced pressure at 1 mmHg or less to obtain 371 g of a yellow hard solid having an average glucose degree of polymerization (n) of 2.4.

The composition of the final product is as follows.

Decyl polyglucoside: at least 97.8% (weight ratio)

Glucose: 0.8% or less

Decyl alcohol: 0.8% or less

Others: Below 0.6% (weight ratio)

Example 4

500 g of dodecyl alcohol, 0.5 g of paratoluene sulfonic acid, 155 g of glucose, 30 g of butanol were placed in a three-necked flask equipped with a mechanical stirrer, a thermometer, and an oil water separator, and heated to 120 to 130 ° C. At this time, the vacuum degree in the reactor is maintained at 30 to 50mmHg and refluxed under reduced pressure for about 2 hours to remove the water produced during the reaction. As the reaction proceeds gradually, the reactants gradually become a pale yellow transparent liquid. After the reaction is completed, the reaction product is cooled to 100 ° C. or lower, and 0.5 g of sodium carbonate is dissolved in 2 cc of water, followed by neutralization. Excess fatty alcohol 383 g was removed by distillation under reduced pressure at 1 mmHg or less to obtain 255.5 g of a yellow hard solid having an average glucose degree of polymerization (n) of 1.4.

The composition of the final product is as follows.

Dodecyl Polyglucoside: More than 98.4% (weight ratio)

Glucose: 0.6% (weight ratio) or less

Dodecyl alcohol: 0.7% (weight ratio) or less

Others: 0.3% (weight ratio) or less

Example 5

In a four-necked flask equipped with a mechanical stirrer, a thermometer, a liquid dropping device, and an oil / water separator, 500 g of dodecyl alcohol, 0.5 g of paratoluene sulfonic acid, 120 g of glucose, and 30 g of hexanol were added and heated to 120 to 130 ° C. At this time, while maintaining the vacuum degree in the reactor to 30 to 50mmHg under reduced pressure reflux for about 2 hours to remove the water produced during the reaction. As the reaction proceeds gradually, the reactants gradually become a pale yellow transparent liquid. After the reaction was completed, 5 g of ethoxy triethylene glycol monoether was added and the reaction was continued for about 1 hour. The reactant is cooled to 100 ° C. or lower, and neutralized by dissolving 0.5 g of sodium carbonate in 2 cc of water. Excess fatty alcohol 380 g was distilled off under reduced pressure at 1 mmHg or less to obtain 323 g of a yellow hard solid having an average glucose degree of polymerization (n) of 1.9.

The composition of the final product is as follows.

Dodecyl Polyglucoside: 96.5% (weight ratio) or more

Glucose: 0.4% (weight ratio) or less

Dodecyl alcohol: 0.6% or less

Others: 2.5% or less

Example 6

500 g of lauryl alcohol (dodecyl alcohol: tetradecyl alcohol = 7: 3, average molecular weight = 192) in a four-necked flask equipped with a mechanical stirrer, a thermometer, a liquid dropping device and an oil water separator, 0.5 g of paratoluene sulfonic acid, 126 g of glucose, hexane Add 30 g of all to heat to 120 to 130 ℃. At this time, while maintaining the vacuum degree in the reactor to 30 to 50mmHg under reduced pressure reflux for about 2 hours to remove the water produced during the reaction. As the reaction proceeds gradually, the reactants gradually become a pale yellow transparent liquid. After the reaction is completed, the reaction is cooled to 100 ° C. or lower, and 0.5 g of sodium carbonate is dissolved in 2 cc of water, followed by neutralization. Excess fatty alcohol 390 g was removed by distillation under reduced pressure at 1 mmHg or less to obtain 250 g of a yellow hard solid having an average glucose degree of polymerization (n) of 1.6.

The composition of the final product is as follows.

Lauryl polyglucoside: 98.4% (weight ratio) or more

Glucose: 0.4% (weight ratio) or less

Lauryl alcohol: 0.8% or less

Others: 0.4% or less

Example 7

500 g of lauryl alcohol (dodecyl alcohol: tetradecyl alcohol = 7: 3, average molecular weight = 192) in a four-necked flask equipped with a mechanical stirrer, a thermometer, a liquid dropping device and an oil water separator, 1 g of paratoluene sulfonic acid, 290 g of glucose, 30 g of butanol Add and heat to 120 to 130 ℃. At this time, the vacuum degree in the reactor is maintained at 30 to 50mmHg and refluxed under reduced pressure for about 2 hours to remove the water produced during the reaction. As the reaction proceeds gradually, the reactants gradually become a pale yellow transparent liquid. After the reaction is completed, 7 g of hexanediol is added, and the reaction is continued for about 1 hour. The reaction is cooled to 100 ° C. or lower, and 0.5 g of sodium carbonate is dissolved in 2 cc of water and neutralized. Excess fatty alcohol 395 g was removed by distillation under reduced pressure at 1 mmHg or less to obtain 368 g of a yellow hard solid having an average glucose degree of polymerization (n) of 3.1.

The composition of the final product is as follows.

Lauryl polyglucoside: 98.4% (weight ratio) or more

Glucose: 0.4% (weight ratio) or less

Lauryl alcohol: 0.8% or less

Others: 0.4% or less

Example 8

In a four-necked flask equipped with a mechanical stirrer, a thermometer, a liquid dropping device and an oil water separator, 500 g of cetyl alcohol (hexadecyl alcohol: octadecyl alcohol = 4: 6, average molecular weight = 258.5), 1 g of paratoluene sulfonic acid, 1 g of glucose, 30 g of octanol Add and heat to 120 to 130 ℃. At this time, the vacuum degree in the reactor is maintained at 30 to 50mmHg and refluxed under reduced pressure for about 2 hours to remove the water produced during the reaction. As the reaction proceeds gradually, the reactants gradually become a pale yellow transparent liquid. After the reaction was completed, 10 g of butoxy hexaethylene glycol monoether was added and the reaction was continued for about 1 hour. The reactant is cooled to 100 ° C. or lower, and neutralized by dissolving 0.5 g of sodium carbonate in 2 cc of water. Excess fatty alcohol 395 g was removed by distillation under reduced pressure at 1 mmHg or less to obtain 219 g of a yellow hard solid having an average glucose degree of polymerization (n) of 1.7.

The composition of the final product is as follows.

Cetyl polyglucoside: 91.8% (weight ratio) or more

Glucose: 0.4% (weight ratio) or less

Cetyl alcohol: 1.4% (weight ratio) or less

Others: Below 6.3% (weight ratio)

According to the present invention, an apparatus for recovering and purifying lower alcohols removed in a two-step reaction using excess ① lower alcohols, transglucosidation, a long time reaction time, a lower alcohol smell, and a solvent are used. Solvent and recovery device in the direct reaction, deterioration of product quality due to residual solvent, and ③ filtering process due to excessive residual unreacted glucose in the direct reaction of glucose and higher fatty alcohol, Difficulties in removal and long reaction time can be solved by using a small amount of lower alcohol and glycols to recover the solvent and filter the purification device, two-step reaction, working environment due to the smell and toxicity of the lower alcohol and solvent. It can improve completely and reduce the reaction time to 2 hours, and also reduce the amount of unreacted glucose to within 0.6%. Writing can get a low manufacturing cost and high quality products.

Thus, it can be seen that the method according to the present invention is an industrially useful invention in the art.

Claims (8)

In the method for preparing a higher alkyl polyglycoside by reacting glucose with higher fatty alcohol in the presence of an acid catalyst, the catalyst is used in an amount of 0.01 to 0.1% (weight ratio) based on the total weight of glucose and higher fatty alcohol, and is also a lower grade as a reaction aid. A method for producing a higher alkylpolyglucoside represented by the following general formula (I), wherein alcohol, glycols or glycol ethers are added in an amount of 1.2 to 20% (molar ratio) based on the weight of glucose. Wherein R is a linear or branched alkyl or alkenyl group having 8 to 22 carbon atoms, and n is 1 to 10 as the average glucose polymerization degree. The process according to claim 1, wherein the higher fatty alcohol is saturated, unsaturated, linear or branched having 8 to 22 carbon atoms. The higher fatty alcohol of claim 2, wherein the higher fatty alcohol is octyl alcohol, nonyl alcohol, decyl alcohol, undecyl alcohol, dodecyl alcohol, tridecyl alcohol, tetradecyl alcohol, pentadecyl alcohol, hexadecyl alcohol, hexadecenyl alcohol, heptadecyl A process for producing alcohols, octadecyl alcohols, octadecenyl alcohols, nonadecyl alcohols, eicosyl alcohols, henicosyl alcohols, tocosyl alcohols or mixed fatty alcohols thereof. The method according to any one of claims 1 to 3, wherein the amount of the higher fatty alcohol is 1 to 7 times by weight based on the amount of glucose used. The process according to any one of claims 1 to 3, wherein the acid catalyst is sulfuric acid, phosphoric acid, hydrochloric acid, paratoluene sulfonic acid or hydroxyl acid. The reaction aid of claim 1, wherein the reaction aid is butanol, pentanol, heptanol, hexanol, octanol, isooctanol, 2-ethylhexanol, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, butyl Lenglycol, hexylene glycol, ethylene di (tri, poly) glycol, propylene di (tri, poly) glycol, methoxy mono (di, tri, poly) ethylene glycol monoether, ethoxy mono (di, tri, poly) Process for producing ethylene glycol monoether, propoxy mono (di, tri, poly) ethylene glycol monoether or butoxy mono (di, tri, poly) ethylene glycol monoether. The method according to claim 1, wherein the reaction is carried out at a reaction temperature of 80 to 170 ° C and a vacuum degree of 10 to 400 mmHg. The method according to claim 7, wherein the reaction is performed in the range of reaction temperature of 100 to 140 DEG C and vacuum degree of 20 to 200 mmHg.