CN112979720B

CN112979720B - Preparation method of alkyl glycoside

Info

Publication number: CN112979720B
Application number: CN202110247575.3A
Authority: CN
Inventors: 宗乾收; 金立军; 王新登; 潘骏; 王治国
Original assignee: Zhejiang Zhengtai Engineering Design Co ltd; Jiaxing University
Current assignee: Zhejiang Zhengtai Engineering Design Co ltd; Jiaxing University
Priority date: 2021-03-06
Filing date: 2021-03-06
Publication date: 2022-10-04
Anticipated expiration: 2041-03-06
Also published as: CN112979720A

Abstract

The application relates to the field of fine chemical engineering, and particularly discloses a preparation method of alkyl glycoside. The preparation method of the alkyl glycoside comprises the following steps: step S1: performing alkylation reaction, mixing and stirring glucose, fatty alcohol and a catalyst at the temperature of 95-130 ℃, filtering and recovering the catalyst when the reaction is finished, and recycling the catalyst, wherein the catalyst is an aromatic sulfonic acid high polymer; step S2: dealcoholizing, namely carrying out multistage pressure reduction dealcoholization on the mixed solution after the alkylation reaction at the temperature of 130-160 ℃ to obtain a pretreated product; and step S3: and (4) decolorizing and compounding, namely adding a decolorizing agent into the pretreated product, and adding water to compound after decolorizing is finished to obtain the product. The process has the advantages of simple operation and recyclable catalyst.

Description

Preparation method of alkyl glycoside

Technical Field

The application relates to the field of fine chemical engineering, in particular to a preparation method of alkyl glycoside.

Background

The alkyl glycoside is a surfactant with low surface tension, strong detergency and compatibility, and the alkyl glycoside is synthesized by a plurality of methods, and is generally produced on a large scale by a direct glycosidation method and a transglycosidation method in the industry at present.

The direct glucoside method is characterized in that glucose and fatty alcohol are subjected to alkylation reaction under the action of a catalyst, and then subjected to neutralization, dealcoholization and decoloration to prepare an alkyl glucoside product.

The transglycosylation method is also called as a two-step synthesis method, and because glucose is insoluble in higher carbon chain fatty alcohol, the glucose is easy to layer; and the compatibility with the lower fatty alcohol is better, so glucose and the lower fatty alcohol are firstly used for reaction. Generally, the preparation method is prepared by carrying out butyl glycosidation reaction with n-butyl alcohol and then carrying out alcohol exchange reaction with higher alcohol, the preparation process is complex, two dealcoholization steps are required, and the production process cost is higher than that of a direct glycosidation method.

In view of the above-mentioned related technologies, the inventors believe that the alkyl glycoside prepared by the above method requires multiple steps of neutralization, dealcoholization, decolorization and the like after alkylation of glucose and fatty alcohol, and the process is complex; on the other hand, the use amount of the catalyst is large, so that the production cost of the alkyl glycoside is high.

Disclosure of Invention

In order to improve the convenience of process operation and recycle the catalyst, the application provides a preparation method of alkyl glycoside.

The preparation method of the alkyl glycoside adopts the following technical scheme:

a method for preparing alkyl glycoside, comprising the steps of:

step S1: performing alkylation reaction, mixing and stirring glucose, fatty alcohol and a catalyst at the temperature of 95-130 ℃, filtering and recovering the catalyst when the reaction is finished, and recycling the catalyst, wherein the catalyst is an aromatic sulfonic acid high polymer;

step S2: dealcoholizing, namely, carrying out multistage pressure reduction dealcoholization on the mixed solution after the alkylation reaction at the temperature of 130-160 ℃ to obtain a pretreated product;

and step S3: decolorizing and compounding, namely adding a decolorizing agent into the pretreated product, and adding water for compounding after decolorizing to obtain the product.

By adopting the technical scheme, because the aromatic sulfonic acid polymer is used as the catalyst, on one hand, the aromatic sulfonic acid polymer can play a good catalytic effect on alkylation reaction, and the quality of an alkyl glycoside product is improved, on the other hand, the catalyst is solid and can be reused after being filtered and recovered, and the repeatedly used catalyst still has a good catalytic effect on the alkylation reaction, so that the utilization rate of the catalyst in the application is improved.

Preferably, the aromatic sulfonic acid high polymer is prepared from the following raw materials: the catalyst comprises polyphenylacetylene, a sulfonating agent and a cocatalyst, wherein the sulfonating agent comprises sulfuric acid, and the mass fraction of the sulfuric acid is 80-90%.

By adopting the technical scheme, the aromatic sulfonic acid high polymer is prepared by the polyphenylacetylene, the sulfuric acid and the cocatalyst in the application, the concentration of the sulfuric acid can influence the sulfonation degree of a product, and the aromatic sulfonic acid high polymer suitable for alkyl glycoside catalysis can be prepared by limiting the concentration of the sulfuric acid, so that the aromatic sulfonic acid high polymer prepared by reaction can repeatedly play a good catalytic effect on alkylation reaction.

Preferably, the promoter comprises silver sulfate, the mass ratio of the polyphenylacetylene to the sulfuric acid is (3-4.5): 1, and the mass of the silver sulfate is 0.5-1% of the mass of the sulfuric acid.

By adopting the technical scheme, the larger the sulfonation rate is, the better the solubility of the product is, the sulfuric acid is used as the sulfonating agent of the application, and the mass ratio of the sulfuric acid to the polyphenylacetylene is controlled, so that the sulfonation rate of aromatic rings in the polyphenylacetylene can be controlled; generally, the larger the molecular weight is, the longer the time required by the sulfonation reaction is, the silver sulfate can be used as a catalyst of the sulfonation reaction to accelerate the sulfonation reaction of sulfuric acid and polyphenylacetylene, and the rate of the reaction can be controlled by limiting the concentration of the silver sulfate.

The preferred aromatic sulfonic acid polymer is processed by the following steps:

step S41: weighing polyphenylacetylene, sulfuric acid and silver sulfate in proportion;

step S42: mixing polyphenylacetylene, sulfuric acid and silver sulfate, and oscillating at constant temperature of 45-55 ℃ for 20-30 hours;

step S43: and (5) carrying out suction filtration, water washing and vacuum drying on the mixture obtained in the step (S42) to obtain the aromatic sulfonic acid polymer.

By adopting the technical scheme, the sulfonation rate of the aromatic ring in the polyphenylacetylene can be influenced by the temperature and the time of the sulfonation reaction, and the preparation of the aromatic sulfonic acid high polymer with the appropriate sulfonation degree as the catalyst of the alkyl glycoside is facilitated by controlling the temperature and the time of the sulfonation reaction.

Preferably, the fatty alcohol used is a fatty alcohol containing 10 or more carbon atoms, and the alkylation reaction in step S1 comprises the steps of:

step S11: pretreating, namely adding glucose into fatty alcohol in batches in sequence, mixing and grinding for 1.5-2.0 hours;

step S12: synthesizing, namely adding a catalyst into the mixture obtained in the step S11, and mixing and stirring for 3-4 hours at 95-130 ℃ under the condition of 2-8 KPa;

step S13: and (4) recovering the catalyst, namely filtering the mixture after the reaction in the step S12 at the temperature of 100-130 ℃ while the mixture is hot, recovering the catalyst, and repeating the step S12 to recycle the catalyst.

By adopting the technical scheme, the glucose is added in batches, so that the possibility of self-polymerization of the glucose is reduced, the condensation reaction of the glucose and the fatty alcohol is a solid-liquid heterogeneous reaction, and therefore the glucose and the fatty alcohol are difficult to fully react under common conditions, the raw materials are crushed and mixed in the step S11, so that the particle size of the materials is reduced, the contact area of the reaction between the alcohol and the sugar is increased, the glycosidation reaction is facilitated, the conversion rate of the glucose is further facilitated to be improved, the pressure is controlled to be 2-8 KPa, and after the reaction between the glucose and the fatty alcohol is carried out under negative pressure, the byproduct water generated by the reaction is evaporated out under negative pressure, so that the reaction is facilitated to be carried out in the positive and negative reactions, and the yield of the alkyl glycoside in the application is improved.

Preferably, the decoloring and compounding step S3 comprises the following steps:

step S31: adding water into the pretreated product, mixing and stirring for 0.5-1 hour;

step S32: and (4) adding a decoloring agent into the mixed liquid obtained in the step (S31), and controlling the reaction temperature to be 60-70 ℃, mixing, stirring and decoloring for 5-7 hours, wherein the decoloring agent comprises hydrogen peroxide.

Step S33: and (5) filtering the liquid decolorized in the step (S32), and adding water into the filtrate to dilute and compound the filtrate to obtain the product.

By adopting the technical scheme, the viscosity of the pre-treated product after dealcoholization treatment is higher, and the dispersion of the alkyl glycoside is facilitated after water is added, so that the contact area of the alkyl glycoside and a decoloring agent is increased, the alkyl glycoside can be better decolored, the purity of the product is improved, and the sugar coked in the solution can be removed through the filter screen in the step S33, so that the purity of the reaction product is improved, and the color of the product is improved.

Preferably, the mass ratio of the fatty alcohol to the glucose is (6-7): 1.

by adopting the technical scheme, when the using amount of the alcohol in the reaction system is excessive, the alcohol can play a role in diluting the catalyst, so that the concentration of the catalyst is reduced, the conversion rate of the glucose is reduced, and the cost of subsequent alcohol recovery is increased when the using amount of the alcohol is excessive; when the consumption of the alcohol in the reaction system is too small, the reactants are too viscous to be beneficial to the alkylation reaction; the alkyl glycoside product with high glucose conversion rate is efficiently prepared by controlling the alcohol-sugar ratio.

Preferably, the mass of the catalyst is 1-5% of the mass of the glucose.

By adopting the technical scheme, the mass ratio of the catalyst to the glucose is controlled, so that the alkylation reaction rate can be controlled, the possibility of glucose coking can be reduced, the glucose and the fatty alcohol are in full contact reaction under the condition of keeping relatively quick reaction, and the purity of the prepared alkyl glycoside is improved.

In summary, the present application has the following advantages:

the catalyst adopted by the method has the advantages that on one hand, the catalyst can play a good catalytic effect on alkylation reaction and is beneficial to improving the quality of the prepared alkyl glycoside product, on the other hand, the catalyst can be recycled for many times, so that the utilization rate of the catalyst in the method is improved, and the aromatic sulfonic acid high polymer is adopted as the catalyst in the method, so that the neutralization steps are reduced, and the production process is simplified.

Detailed Description

The present application will be described in further detail with reference to examples.

Starting materials

TABLE 1 raw materials used in the present invention

Starting materials	CAS number/concentration	Manufacturer of the product
			Anhydrous glucose	CAS：200-075-1	Jintong chemical industry Co, ltd
N-dodecanol	CAS：112-53-8	Chemical Co., ltd
			Sulfuric acid	CAS：7664-93-9	Hencao chemical Co., ltd, deqing county
Magnesium oxide	CAS：1309-48-4	Shandong AoChuang chemical Co Ltd
			Hydrogen peroxide solution	The mass concentration is 30 percent	Jinan Dakui chemical Co Ltd
Para toluene sulfonic acid	CAS：6192-52-5	Shanghai Kaiyn chemical Co., ltd
			Silver sulfate	CAS：10294-26-5	Chengdu Xixia chemical reagent limited

Preparation example 1

Preparation of polyphenylacetylene:

the preparation method of the polyphenylacetylene by adopting phenylacetylene polymerization with the publication number of CN110054719A comprises the following steps: adding 0.01 equivalent of rhodium catalyst into a 25mL clean Schlenk reaction tube, exhausting and ventilating for 15 minutes under argon atmosphere, then adding a certain amount of tetrahydrofuran solution under argon atmosphere, carrying out freeze degassing for 45 minutes in liquid nitrogen, returning to room temperature, adding 1 equivalent of treated phenylacetylene under argon atmosphere, initiating polymerization reaction of phenylacetylene at room temperature, after reacting for a certain time, finally adding a large amount of methanol into a reaction system to carry out quenching reaction, centrifuging, separating, and then vacuumizing to constant weight to prepare the polyphenylacetylene.

Preparation example 2

Preparation of aromatic sulfonic acid polymer:

step S41: weighing polyphenylacetylene and 85% sulfuric acid according to the mass ratio of 4;

step S42: adding silver sulfate into sulfuric acid to obtain a sulfonating agent, mixing polyphenylacetylene and the sulfonating agent in an oscillator (TP 671 multifunctional oscillator, new dimension measurement and control equipment Co., ltd. Of Beijing era), oscillating at a constant temperature of 45-55 ℃ for 25 hours, intermittently adding 90-95% by mass of sulfuric acid in the sulfonation process, and controlling the mass fraction of the sulfuric acid in the mixed solution to be 85%; step S43: and (3) carrying out vacuum filtration and water washing on the mixed solution obtained after the reaction in the step (S42), and then carrying out vacuum drying in a drying oven (a vacuum drying oven with model number of DZF-6020N of Stannless Marrei technologies Co., ltd.) to obtain the aromatic sulfonic acid polymer.

Preparation example 3

The difference between preparation 3 and preparation 2 is that: the mass ratio of the polyphenylacetylene to the sulfuric acid in the preparation example 3 is 3.

Preparation example 4

The difference between preparation 4 and preparation 2 is that: the mass fraction of the sulfuric acid used in preparation example 4 was 80%, and the contents of the remaining components were the same as those in preparation example 2.

Preparation example 5

The difference between preparation 5 and preparation 2 is that: the mass of silver sulfate in preparation example 5 was 1% of the mass of sulfuric acid, and the contents of the remaining components were the same as those in preparation example 2.

Examples

Example 1

In the application, taking the preparation of dodecyl glycoside as an example, n-dodecyl alcohol is adopted as fatty alcohol, and a preparation method of alkyl glycoside is as follows:

step S1: an alkylation reaction, the alkylation reaction comprising the steps of:

step S11: pretreatment, namely pretreating the mixture according to the mass ratio of 6.5:1, respectively preparing fatty alcohol and glucose, wherein the glucose needs to be screened by a 2500-mesh filter screen to obtain glucose particles with the particle size of less than 5 microns, completely introducing the fatty alcohol into a colloid mill (a colloid mill with the model of JNS-240 in Hennuo machinery Co., ltd., gallery), dividing the glucose into 5 batches with equal mass, sequentially adding the 5 batches into the colloid mill, mixing and grinding for 2 hours, wherein the rotating speed of the colloid mill is controlled at 1700-2000r/min;

step S12: synthesizing, namely adding a catalyst into the mixture pretreated in the step S11, and mixing and stirring for 3.5 hours at 110 ℃ and under the condition of 5KPa, wherein the catalyst is the aromatic sulfonic acid high polymer prepared in the preparation example 2, and the mass of the catalyst is 0.3 percent of that of glucose;

step S13: recovering the catalyst, namely filtering the reaction mixture in the step S12 at the temperature of 120 ℃ while the reaction mixture is hot to recover the catalyst, and repeating the step S12 to recycle the catalyst;

step S2: dealcoholizing, namely performing primary reduced pressure distillation on the mixed solution reacted in the step S12 through a falling film evaporator under the conditions of absolute pressure of 50Pa and temperature of 135 ℃, introducing the liquid distilled by the falling film evaporator into a wiped film evaporator, and performing secondary distillation under the conditions of absolute pressure of 25Pa and temperature of 160 ℃ to obtain a pretreated product, wherein the fatty alcohol subjected to the secondary reduced pressure distillation can be recycled;

and step S3: the decolorizing and compounding process comprises the following steps:

step S32: adding the mixed solution obtained in the step S31, hydrogen peroxide and magnesium oxide into a reaction kettle (an electric heating reaction kettle of Shanghai Suixing electro-mechanical development Co., ltd.) in sequence, controlling the reaction temperature to 65 ℃, and mixing and stirring for 6 hours;

step S33: and (4) filtering the aqueous solution decolorized in the step (S32), removing monosaccharide, polysaccharide and coked sugar, and adding water into the filtrate to dilute to obtain a dodecyl glucoside product with the solid content of 50%.

Example 2

Example 2 differs from example 1 in that: the catalyst in example 1 was replaced with the arylsulfonic acid polymer prepared in preparative example 3 of equivalent mass.

Example 3

Example 3 differs from example 1 in that: the catalyst in example 1 was replaced with the arylsulfonic acid polymer prepared in preparative example 4 of equivalent mass.

Example 4

Example 4 differs from example 1 in that: the catalyst in example 4 was replaced with the arylsulfonic acid polymer prepared in preparative example 5 of equivalent mass.

Example 5

Example 5 differs from example 1 in that: in example 5, the mass ratio of fatty alcohol to glucose was 7:1, the content of the rest components is the same as that of the component in the example 1.

Example 6

Example 6 differs from example 1 in that: the mass of the catalyst in example 6 was 5% of the mass of glucose, and the contents of the remaining components were the same as those in example 1.

Example 7

Example 7 differs from example 1 in that: different from dealcoholization treatment, the first reduced pressure distillation is carried out in step S21 by a falling film evaporator only under the conditions of absolute pressure of 50Pa and 135 ℃, and the second distillation is not carried out in a wiped film evaporator in example 7; the remaining steps were the same as in example 1.

Example 8

Example 8 differs from example 1 in that: example 8 in step S21 distillation was carried out only at absolute pressure 25Pa, 160 ℃ and no distillation was carried out in falling film evaporator; the remaining steps were the same as in example 1.

Example 9

Example 9 differs from example 1 in that: example 9 in step S32, no magnesium oxide was added and the remaining steps were the same as in example 1.

Comparative example

Comparative example 1

Comparative example 1 differs from example 1 in that: comparative example 1 the catalyst used in step S12 was different, and in comparative example 1, the catalyst of example 1 was replaced with an equal mass portion of p-toluenesulfonic acid, and the remaining component contents were the same as in example 1.

Comparative example 2

Comparative example 2 differs from example 1 in that: in comparative example 2, during step S1, the ratio by mass was 6:1 after preparing fatty alcohol and glucose respectively, without the step S11, the catalyst, fatty alcohol and glucose were directly mixed in a reaction kettle, and stirred for 3.5 hours under the conditions of temperature of 110 ℃ and pressure of 5KPa, and the contents of the remaining components were the same as those in example 1.

Performance test

Respectively extracting the alkyl glycoside products prepared in examples 1-9 and comparative examples 1-2 for performance test, performing performance test on the alkyl glycoside product bottle prepared in each example or comparative example for three times, and finally taking the average value of the data detected by the three performance tests, wherein the specific result is shown in table 3;

1. appearance: product appearance by sensory measurement;

2. color: measuring by using GB/T19464-2014 alkyl glycoside, preparing an alkyl glycoside sample prepared by reaction into a solution by using a mixed solvent of isopropanol and water, wherein the solution is in a transparent state under the condition that the pH value is equal to 7, visual colorimetry is carried out on the solution and a standard platinum-cobalt series color code, and the Hazen value of the standard platinum-cobalt color code closest to the color of the product is the color of the product;

3. the product purity is as follows: the purity of the powdery alkyl glycoside is obtained through gas chromatography detection and analysis;

4. average degree of polymerization: measuring by using GB/T19464-2014 alkyl glycoside, and calculating the polymerization degree of the product by using an area normalization method;

5. catalyst reusability test: taking example 1 as an example, after step S12, step S13 was repeated, and the effect of the catalyst after 1, 3, 5, 7, and 9 cycles on the purity of the alkyl glycoside product was examined, and the specific results are shown in table 2.

Detection method/test method

TABLE 2 detection results of catalyst with different cycle times on product purity

TABLE 3 test results of products in examples 1 to 9 and comparative examples 1 to 2

Test items	Appearance of the product	color/Hazen	Purity of product/%)	Average degree of polymerization
					Example 1	Colorless transparent liquid	16	98.4	1.16
Example 2	Colorless transparent liquid	24	97.7	1.28
					Example 3	Colorless transparent liquid	25	97.6	1.29
Example 4	Colorless transparent liquid	23	97.8	1.27
					Example 5	Colorless transparent liquid	22	97.5	1.24
Example 6	Colorless transparent liquid	24	97.4	1.23
					Example 7	Colorless transparent liquid	28	97.2	1.29
Example 8	Colorless transparent liquid	29	97.1	1.28
					Example 9	Colorless transparent liquid	22	97.8	1.23
Comparative example 1	Light yellow transparent liquid	37	94.7	1.40
					Comparative example 2	Light yellow transparent liquid	33	95.5	1.33

By combining the example 1 and the comparative example 1, and the tables 2 and 3, it can be seen that the high-quality alkyl glycoside with low average polymerization degree, good stability, high purity and light color can be obtained by using the high polymer of the aromatic sulfonic acid as the catalyst for the alkylation reaction, and the high polymer of the aromatic sulfonic acid still has good catalytic effect after being recycled for multiple times.

Combining examples 1-4, comparative example 1, and table 2, it can be seen that the mass fraction of sulfuric acid, the mass ratio of sulfuric acid to polyphenylacetylene, and the mass ratio of silver sulfate to sulfuric acid all affect the catalytic effect of the aromatic sulfonic acid polymer, and when 85% by mass of sulfuric acid is used, the mass ratio of polyphenylacetylene to sulfuric acid is 4, and the mass of silver sulfate is 0.7% of sulfuric acid, the catalytic effect of the catalyst on the alkylation reaction is the best.

Combining example 1, examples 5-6 and combining table 3, it can be seen that the mass ratio of fatty alcohol to glucose is 6: when the mass of the catalyst is 3 percent of the mass of the glucose, the product quality of the alkyl glycoside prepared by the reaction is optimal.

As can be seen by combining example 1, examples 7-8 and Table 3, the product has better purity and color after two times of vacuum distillation dealcoholization.

The specific embodiments are only for explaining the present application and are not limiting to the present application, and those skilled in the art can make modifications to the embodiments without inventive contribution as required after reading the present specification, but all the embodiments are protected by patent law within the scope of the claims of the present application.

Claims

1. A method for preparing alkyl glycoside, which is characterized by comprising the following steps:

step S2: dealcoholizing, namely carrying out multistage pressure reduction dealcoholization on the mixed solution after the alkylation reaction at the temperature of 130-160 ℃ to obtain a pretreated product;

and step S3: decolorizing and compounding, namely adding a decolorizing agent into the pretreated product, and adding water for compounding after decolorizing to obtain a product;

the aromatic sulfonic acid high polymer is prepared from the following raw materials: the catalyst comprises polyphenylacetylene, a sulfonating agent and a cocatalyst, wherein the sulfonating agent comprises sulfuric acid, and the mass fraction of the sulfuric acid is 80-90%;

the cocatalyst comprises silver sulfate, the mass ratio of the polyphenylacetylene to the sulfuric acid is (3-4.5) 1, and the mass of the silver sulfate is 0.5-1% of the mass of the sulfuric acid;

the aromatic sulfonic acid high polymer is processed by the following steps:

step S41: weighing polyphenylacetylene, sulfuric acid and silver sulfate according to a proportion;

step S43: filtering the mixture obtained in the step S42 by suction, washing with water, and drying in vacuum to obtain an aromatic sulfonic acid polymer; the fatty alcohol is fatty alcohol containing 10 or more carbon atoms,

the alkylation reaction in step S1 comprises the following steps:

step S12: synthesizing, namely adding a catalyst into the mixture obtained in the step S11, and mixing and stirring for 3-4 hours at the temperature of 95-130 ℃ and under the condition of 2-8 KPa;

step S13: recovering the catalyst, namely filtering the mixture reacted in the step S12 at 120-130 ℃ while the mixture is hot, recovering the catalyst, and repeating the step S12 to recycle the catalyst;

the step S3 of decolorizing and compounding comprises the following steps:

step S32: adding a decoloring agent into the mixed solution obtained in the step S31, and controlling the reaction temperature to be 60-70 ℃, mixing, stirring and decoloring for 5-7 hours, wherein the decoloring agent comprises hydrogen peroxide;

step S33: and (5) filtering the liquid decolorized in the step (S32), and adding water into the filtrate for diluting and compounding to obtain the product.

2. The method for preparing an alkylglycoside according to claim 1, wherein: the mass ratio of the fatty alcohol to the glucose is (6-7): 1.

3. the method for preparing an alkylglycoside according to claim 1, wherein: the mass of the catalyst is 1-5% of the mass of the glucose.