阅读说明：本技术 一种多取代乙烷类烷烃的制备方法及其应用 (Preparation method and application of polysubstituted ethane alkane ) 是由 许苗云 孙晏 温玉萍 于 2021-08-05 设计创作，主要内容包括：本发明公开了一种多取代乙烷类烷烃的制备方法及其应用,所述制备方法包括以下步骤：在惰性气氛下,将原料醇加入反应釜中,再加入溶剂、脱水催化剂和稳定剂后进行反应,反应后进行精馏,将馏分分水得到烯烃；将烯烃加入氢化釜中,再加入水和氢化催化剂,置换氮气后加氢氢化,氢化结束后,过滤除掉催化剂,分水得到多取代乙烷类烷烃产品；本发明制备的多取代乙烷类烷烃在生产过程中不产生废弃物,生产过程中除主物料外的所有物料都可以多次套用；加入的水可以极大地降低生产过程中静电的产生,从而极大地提高产品生产的安全性；本发明制备的多取代乙烷类烷烃收率高达于98％,纯度大于99.8％。(The invention discloses a preparation method and application of polysubstituted ethane alkane, wherein the preparation method comprises the following steps: under inert atmosphere, adding raw material alcohol into a reaction kettle, adding a solvent, a dehydration catalyst and a stabilizer, reacting, rectifying after reaction, and separating water from fractions to obtain olefin; adding olefin into a hydrogenation kettle, adding water and a hydrogenation catalyst, replacing nitrogen, hydrogenating, filtering to remove the catalyst after hydrogenation is finished, and dividing water to obtain a polysubstituted ethane alkane product; the polysubstituted ethane alkane prepared by the invention does not generate waste in the production process, and all materials except the main material can be reused for many times in the production process; the added water can greatly reduce the generation of static electricity in the production process, thereby greatly improving the safety of product production; the yield of the polysubstituted ethane alkane prepared by the invention is up to 98 percent, and the purity is more than 99.8 percent.)

1. A preparation method of polysubstituted ethane alkane is characterized in that: the preparation method comprises the following steps:

olefin synthesis: under inert atmosphere, adding raw material alcohol into a reaction kettle, adding a solvent, a dehydration catalyst and a stabilizer, reacting, rectifying after reaction, and separating water from fractions to obtain olefin;

hydrogenation: adding olefin into a hydrogenation kettle, adding water and a hydrogenation catalyst, replacing nitrogen, hydrogenating, filtering to remove the hydrogenation catalyst after hydrogenation is finished, and separating water to obtain a multi-substituted ethane alkane product.

2. The method according to claim 1, wherein the reaction mixture comprises:

the reaction route of the preparation method is as follows:

wherein, R1, R2, R3, R4 and R5 are respectively selected from one of alkyl, the alkyl comprises hydrogen, methyl, ethyl or propyl, the sum of carbon numbers in R1, R2, R3, R4 and R5 is more than 6 and less than or equal to 12, and at least three groups of R1, R2, R3, R4 and R5 are not hydrogen.

3. The method according to claim 1, wherein the reaction mixture comprises:

the mass ratio of the solvent to the raw material alcohol is 0.1-1: 1; the molar ratio of the dehydration catalyst to the raw material alcohol is 1-10: 100, respectively; the molar ratio of the stabilizer to the raw material alcohol is 0.1-1: 100.

4. the method according to claim 1, wherein the reaction mixture comprises:

the volume ratio of water to olefin in the hydrogenation process is 0.1-1: 1, and the addition amount of the hydrogenation catalyst is 0.1-5 wt% of the olefin.

5. The method according to claim 1, wherein the reaction mixture comprises:

the pressure in the hydrogenation process is 0.1-1 MPa; the hydrogenation time is 2-12 hours.

6. The method according to claim 1, wherein the reaction mixture comprises: the solvent comprises one or a mixture of water and N-N-dimethylformamide; the dehydration catalyst is one of organic acid, inorganic acid or Lewis acid.

7. The method according to claim 1, wherein the reaction mixture comprises:

the solvent is preferably water.

8. The method according to claim 1, wherein the reaction mixture comprises:

the hydrogenation catalyst comprises palladium on carbon, raney nickel and platinum on carbon.

9. The method according to claim 1, wherein the reaction mixture comprises:

when the temperature of the distilled fraction is less than 100 ℃, concentrating the residue in the reactor until the residual liquid in the reaction kettle accounts for 10-100% of the weight of the raw material alcohol;

and when the temperature of the distilled fraction is higher than 100 ℃, water is separated from the fraction, and the separated water is added into the reaction kettle until the residual liquid in the reaction kettle accounts for 10-100% of the weight of the raw material alcohol.

10. An application of polysubstituted ethane alkane in the field of petrochemical industry is characterized in that,

the polysubstituted ethane alkanes are prepared by the preparation method of any one of claims 1 to 9.

Technical Field

The invention belongs to the technical field of organic synthesis, and particularly relates to a preparation method and application of polysubstituted ethane alkane.

Background

The existing preparation method of the polysubstituted ethane alkane is prepared by a high-pressure catalysis method, the content of a target product is low, the safety of the preparation method is not high, and the preparation method is not suitable for industrialization. Particularly, for the production of some multi-substituted ethane alkanes with high added value and low capacity demand, the equipment investment is required to be overlarge, so that the cost is extremely high, and the application of the product is greatly limited.

The branched alkane belongs to one of polysubstituted ethane alkanes, has wide application range, such as isooctane, and is used as an additive of motor gasoline and aviation gasoline. Butadiene is used as a solvent in the polymerization. It can also be used for organic synthesis, solvent and gas chromatography. Meanwhile, the intermediate olefin can also be used for synthesizing olefin polymers with high purity, or can be used as an additive for improving the performance of polyolefin and the like. The currently reported synthesis method of branched alkane generally has the problem of low yield, the yield is usually below 20%, the used catalyst is expensive, the dosage is large, and the catalyst cannot be recycled, so that the industrial large-scale production cannot be realized.

Chinese patent CN110590489A discloses a preparation method of branched alkane, which takes pinacolone as a raw material and uses an alkyl metal reagent for alkylation reaction to obtain a corresponding alkyl alcohol intermediate; the alkyl alcohol intermediate uses alkyl silane as a reducing agent, and carries out elimination reduction reaction in the presence of an acid catalyst, so as to synthesize branched alkane; however, the synthesis route generates more hazardous waste and is higher in cost.

Disclosure of Invention

In order to solve the problems, the invention provides a preparation method of polysubstituted ethane alkane, which comprises the following steps:

olefin synthesis: under inert atmosphere, adding raw material alcohol into a reaction kettle, adding a solvent, a dehydration catalyst and a stabilizer, reacting, rectifying after reaction, and separating water from fractions to obtain olefin;

hydrogenation: adding olefin into a hydrogenation kettle, adding water and a hydrogenation catalyst, replacing nitrogen, hydrogenating, filtering to remove the hydrogenation catalyst after hydrogenation is finished, and separating water to obtain a multi-substituted ethane alkane product.

The reaction route of the preparation method is as follows:

wherein, R1, R2, R3, R4 and R5 are respectively selected from one of alkyl, the alkyl comprises hydrogen, methyl, ethyl or propyl, the sum of carbon numbers in R1, R2, R3, R4 and R5 is more than 6 and less than or equal to 12, and at least three groups in R1, R2, R3, R4 and R5 are not hydrogen.

Further, the mass ratio of the solvent to the raw material alcohol is 0.1-1: 1; the molar ratio of the dehydration catalyst to the raw material alcohol is 1-10: 100, respectively; the molar ratio of the stabilizer to the raw material alcohol is 0.1-1: 100.

furthermore, the volume ratio of water to olefin in the hydrogenation process is 0.1-1: 1, and the adding amount of the hydrogenation catalyst is 0.1-5 wt% of the olefin.

Further, the pressure in the hydrogenation process is 0.1-1 MPa; the hydrogenation time is 2-12 hours.

Further, the solvent comprises one or a mixture of water and N-N-Dimethylformamide (DMF); the dehydration catalyst is one of organic acid, inorganic acid or Lewis acid.

Further, the solvent is preferably water.

Further, the hydrogenation catalyst includes palladium on carbon, raney nickel, and platinum on carbon.

When the temperature of the distilled fraction is less than 100 ℃, concentrating the residue in the reactor until the residual liquid in the reaction kettle accounts for 10-100% of the weight of the raw material alcohol;

when the temperature of the distilled fraction is higher than 100 ℃, water is separated from the olefin, and the separated water is added into the reaction kettle until the residual liquid in the reaction kettle accounts for 10-100% of the weight of the raw material alcohol.

The polysubstituted ethane alkane prepared by the invention can be applied in the field of petrochemical industry.

The invention has the advantages that:

the polysubstituted ethane alkane prepared by the invention basically does not generate waste in the production process, and all materials except the main material can be reused for many times in the production process; the added water can greatly reduce the generation of static electricity in the production process, thereby greatly improving the safety of product production; the yield of the polysubstituted ethane alkane prepared by the invention is higher than 98 percent, and the purity is higher than 99.8 percent.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and those skilled in the art can also obtain other drawings according to the drawings without creative efforts.

FIG. 1 shows a synthetic scheme for making polysubstituted ethane alkanes in an example of the present invention;

FIG. 2 shows a gas chromatogram of the product prepared in example 1 of the present invention;

FIG. 3 shows a gas chromatogram of the product prepared in example 2 of the present invention;

FIG. 4 shows a gas chromatogram of the product prepared in example 3 of the present invention;

FIG. 5 shows the resonance hydrogen spectrum of 2,3, 4-trimethylpentane in examples 1-3 of the invention;

FIG. 6 shows a gas chromatogram of the product prepared in example 4 of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention provides a preparation method of polysubstituted ethane alkane, which prepares corresponding olefin through dehydration of corresponding raw material alcohol, and then reduces the olefin to obtain the corresponding polysubstituted ethane alkane with high purity.

The reaction scheme is shown in figure 1, wherein R1, R2, R3, R4 and R5 represent hydrogen, methyl, ethyl, propyl and other groups, wherein the number of carbons in R1, R2, R3, R4 and R5 is more than 6, but generally not more than 12, and at least three groups are not hydrogen.

The preparation method comprises the following steps:

olefin synthesis: under inert atmosphere, adding corresponding raw material alcohol into a reaction kettle, and then adding a solvent (comprising water, N-N-dimethylformamide), a dehydration catalyst and a stabilizer for reaction; and starting to collect the fraction until the temperature of the top in the reaction kettle reaches the equilibrium temperature, stopping collecting when the temperature of the top of the reaction kettle begins to change (rise or fall), and dividing the fraction to obtain the olefin. The raw material alcohol is alcohol containing alpha hydrogen, and the amount of the added solvent is 10-100% of the weight of the raw material alcohol (namely the mass ratio of the solvent to the raw material alcohol is 0.1-1: 1); the dehydration catalyst is 1-10 mol% of the raw material alcohol (namely, the molar ratio of the dehydration catalyst to the raw material alcohol is 1-10: 100); the amount of the stabilizer to be added is not strictly limited, the kind of the stabilizer is related to the structure of the olefin product, and can be adjusted according to specific conditions, and the stabilizer can be 2, 6-di-tert-butyl-4-methylphenol (BHT), which is 0.1-1 mol% of the raw material alcohol (i.e. the molar ratio of the stabilizer to the raw material alcohol is 0.1-1: 100); the inert gas can be nitrogen, helium, and argon; the dehydration catalyst can be inorganic acid, organic acid and Lewis acid, the inorganic acid is hydrochloric acid, sulfuric acid and nitric acid, the organic acid is sulfonic acid and sulfinic acid, and the sulfonic acid is p-toluenesulfonic acid and trifluoromethanesulfonic acid; the sulfinic acid is p-toluene sulfinic acid; the Lewis acid is aluminum trichloride, ferric trichloride, boron trifluoride and zinc chloride; the stabilizer can avoid the polymerization of olefin to improve the purity of the product. The above materials are exemplary, not limiting.

If the temperature of the distillate is lower than 100 ℃, the residue in the reaction kettle needs to be concentrated to remove a proper amount of water, and the residue is applied to the next batch; if the distillate is distilled off at > 100 ℃, the water separated off needs to be added to an appropriate amount of reaction flask for the next batch, and the residual concentration will contain the catalyst, the stabilizer, water and a small amount of the raw material alcohol.

Synthesis of the target product (hydrogenation): adding the obtained olefin into a hydrogenation kettle, adding water and a hydrogenation catalyst, replacing nitrogen, and hydrogenating, wherein the hydrogenation pressure is 0.1-1MPa (which can be properly adjusted according to the hydrogenation reaction speed); the adding amount of water in the hydrogenation process is 0.1-1 time of the volume ratio of the olefin, and the adding amount of the hydrogenation catalyst is 0.1-5% of the weight ratio of the olefin; wherein, the hydrogenation catalyst comprises palladium carbon, Raney nickel, platinum carbon and the like. And after the hydrogenation is finished, filtering to remove the catalyst, and separating water to obtain a product, wherein the filtered catalyst can be recycled.

The above routes are illustrated below in specific examples, where the data and materials set forth in the examples are exemplary representations and do not demonstrate all of the examples.

Example 1

2,3, 4-trimethylpentane is prepared by taking 2,3, 4-trimethyl-3-pentanol as raw material alcohol.

The reaction process is as follows:

olefin synthesis: adding 2,3, 4-trimethyl-3-pentanol into a rectification reaction kettle in a nitrogen atmosphere, and then adding water, sulfuric acid and BHT for reaction (the molar ratio of the 2,3, 4-trimethyl-3-pentanol to the BHT to the sulfuric acid is 100:0.1:1, and the mass ratio of the water to the 2,3, 4-trimethyl-3-pentanol is 0.1: 1); and the distillation temperature of the main distillation fraction of the rectification is 96 ℃ until the temperature of the top part in the reaction kettle reaches the equilibrium temperature, the fraction starts to be collected, when the temperature of the top part of the reaction kettle starts to change, the collection is stopped, and the fraction is subjected to water division to obtain the 2,3, 4-trimethyl-2-pentene.

Synthesis of 2,3, 4-trimethylpentane: adding the 2,3, 4-trimethyl-2-pentene obtained in the previous step into a hydrogenation kettle, and then adding water; the adding amount of water is 0.1 time of the volume of 2,3, 4-trimethyl-2-pentene, and palladium carbon accounting for 0.1 percent of the weight of 2,3, 4-trimethyl-2-pentene is added for catalysis; stirring and dissolving, replacing nitrogen, wherein the nitrogen replacement process can be carried out for multiple times, then pumping out nitrogen, introducing hydrogen for hydrogenation reaction, keeping the hydrogenation reaction pressure at 0.2MPa for 2 hours, separating an organic layer and a water layer after the reaction, and collecting the separated organic layer to obtain 2,3, 4-trimethylpentane; the water layer can be directly used in the step, nitrogen replacement is carried out after the reaction is finished, the pressure of the nitrogen is kept at 0.2MPa to carry out filter pressing on the reaction system, and the catalyst palladium-carbon is recovered.

The yield of the reaction is more than or equal to 99 percent, the retention time of the 2,3, 4-trimethylpentane is 7.753 minutes, and the purity is 99.84 percent (as shown in figure 2).

Example 2

2,3, 4-trimethylpentane is prepared by taking 2,3, 4-trimethyl-3-pentanol as raw material alcohol.

The reaction process is as follows:

olefin synthesis: adding 2,3, 4-trimethyl-3-pentanol into a rectification reaction kettle under a nitrogen atmosphere, and adding DMF, sulfonic acid and BHT for reaction (the molar ratio of the 2,3, 4-trimethyl-3-pentanol to the BHT to the sulfonic acid is 100: 0.5: 5, and the mass ratio of the DMF to the 2,3, 4-trimethyl-3-pentanol is 0.5: 1); and the distillation temperature of the main distillation fraction of the rectification is 96 ℃ until the temperature of the top part in the reaction kettle reaches the equilibrium temperature, the fraction starts to be collected, when the temperature of the top part of the reaction kettle starts to change, the collection is stopped, and the fraction is subjected to water division to obtain the 2,3, 4-trimethyl-2-pentene.

Synthesis of 2,3, 4-trimethylpentane: adding the 2,3, 4-trimethyl-2-pentene obtained in the previous step into a hydrogenation kettle, and then adding water; adding water in an amount which is 0.5 times the volume of 2,3, 4-trimethyl-2-pentene, adding Raney nickel accounting for 2.5 percent of the weight of the 2,3, 4-trimethyl-2-pentene for catalysis, stirring and dissolving, replacing nitrogen, performing nitrogen replacement for multiple times, pumping out nitrogen, introducing hydrogen for hydrogenation reaction, keeping the hydrogenation reaction pressure at 0.5MPa for 8 hours, separating an organic layer and a water layer after the reaction, and collecting the separated organic layer to obtain 2,3, 4-trimethylpentane; the water layer can be directly used in the step, nitrogen replacement is carried out after the reaction is finished, the pressure of the nitrogen is kept at 0.2MPa to carry out filter pressing on the reaction system, and the catalyst Raney nickel is recovered.

The yield of the reaction is more than or equal to 98.2 percent, the retention time of the 2,3, 4-trimethylpentane is 7.756 minutes, and the purity is 99.81 percent (as shown in figure 3).

Example 3

2,3, 4-trimethylpentane is prepared by taking 2,3, 4-trimethyl-3-pentanol as raw material alcohol.

The reaction process is as follows:

olefin synthesis: adding 2,3, 4-trimethyl-3-pentanol into a rectification reaction kettle under an argon atmosphere, and adding water, zinc chloride and BHT for reaction (the molar ratio of the 2,3, 4-trimethyl-3-pentanol to the BHT to the zinc chloride is 100: 1: 10, and the mass ratio of the water to the 2,3, 4-trimethyl-3-pentanol is 1: 1); and the distillation temperature of the main distillation fraction of the rectification is 96 ℃ until the temperature of the top part in the reaction kettle reaches the equilibrium temperature, the fraction starts to be collected, when the temperature of the top part of the reaction kettle starts to change, the collection is stopped, and the fraction is subjected to water division to obtain the 2,3, 4-trimethyl-2-pentene.

Synthesis of 2,3, 4-trimethylpentane: adding the 2,3, 4-trimethyl-2-pentene obtained in the previous step into a hydrogenation kettle, and then adding water; adding platinum carbon accounting for 5 percent of the weight of the 2,3, 4-trimethyl-2-pentene into the mixture, carrying out catalysis, stirring and dissolving, replacing nitrogen, wherein the nitrogen replacement process can be carried out for multiple times, then pumping out nitrogen, introducing hydrogen into the mixture to carry out hydrogenation reaction, keeping the hydrogenation reaction at the pressure of 1MPa for 12 hours, separating an organic layer and a water layer after the reaction, and collecting the separated organic layer to obtain 2,3, 4-trimethylpentane; the water layer can be directly used in the step, nitrogen replacement is carried out after the reaction is finished, the pressure of the nitrogen is kept at 0.2MPa to carry out filter pressing on the reaction system, and the catalyst platinum carbon is recovered.

The yield of the reaction is more than or equal to 98.5 percent, the retention time of the 2,3, 4-trimethylpentane is 7.766 minutes, and the purity is 99.83 percent (as shown in figure 4).

The products of examples 1-3 were subjected to NMR measurement, and the hydrogen resonance spectrum was shown in Table 5, and the specific data is shown in Table 1, 1.562H CH (CH)₃)₂，0.99 1H CHCH₃，0.82 12H CH(CH₃)₂,0.77 3H CHCH₃Wherein italics is the labeled hydrogen.

Example 4

2,2, 3, 4-tetramethyl-pentane is prepared by using 2,2, 3, 4-tetramethyl-3-pentanol as raw material alcohol.

The reaction route is as follows:

olefin synthesis: adding 2,2, 3, 4-tetramethyl-3-pentanol into a rectification reaction kettle in a nitrogen atmosphere, and then adding water, sulfuric acid and BHT for reaction (the molar ratio of the 2,2, 3, 4-tetramethyl-3-pentanol to the BHT to the sulfuric acid is 100:0.1:1, and the mass ratio of the water to the 2,2, 3, 4-tetramethyl-3-pentanol is 0.1: 1); and the distillation temperature of the main distillation fraction of the rectification is 98 ℃ until the top temperature in the reaction kettle reaches the equilibrium temperature, the fraction starts to be collected, when the top temperature of the reaction kettle starts to change, the collection is stopped, and the fraction is subjected to water division to obtain the 2,3,4, 4-tetramethyl-2-pentene.

Synthesis of 2,2, 3, 4-tetramethylpentane: adding the 2,3,4, 4-tetramethyl-2-pentene obtained in the previous step into a hydrogenation kettle, and then adding water; the adding amount of water is 0.1 time of the volume of 2,3,4, 4-tetramethyl-2-pentene, and palladium carbon accounting for 0.1 percent of the weight of the 2,3,4, 4-tetramethyl-2-pentene is added for catalysis; stirring and dissolving, replacing nitrogen, wherein the nitrogen replacement process can be carried out for multiple times, then pumping out nitrogen, introducing hydrogen for hydrogenation reaction, keeping the hydrogenation reaction pressure at 0.2MPa for 2 hours, separating an organic layer and a water layer after the reaction, and collecting the separated organic layer to obtain 2,2, 3, 4-tetramethylpentane; the water layer can be directly used in the step, nitrogen replacement is carried out after the reaction is finished, the pressure of the nitrogen is kept at 0.2MPa to carry out filter pressing on the reaction system, and the catalyst palladium-carbon is recovered.

The yield of the reaction is more than or equal to 98 percent, the retention time of the 2,2, 3, 4-tetramethylpentane is 8.103 minutes, and the purity is 99.86 percent (as shown in figure 6).

The results of gas chromatography measurements of examples 1 to 4 are shown in Table 2

From the results, the purity of the polysubstituted ethane alkane prepared by the technical route of the invention reaches more than 99.8 percent, the yield also reaches more than 98 percent, and the high conversion of the raw materials and the high purity of the product are realized.

Although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.