CN114773258B - Separation and purification method of 2, 6-lutidine - Google Patents
Separation and purification method of 2, 6-lutidine Download PDFInfo
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- C07D213/02—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
- C07D213/04—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom
- C07D213/06—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom containing only hydrogen and carbon atoms in addition to the ring nitrogen atom
- C07D213/16—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom containing only hydrogen and carbon atoms in addition to the ring nitrogen atom containing only one pyridine ring
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Abstract
The application discloses a separation and purification method of 2, 6-lutidine, which uses a double diethoxy column [5]]The arene crystal material is an adsorbent, and can selectively adsorb 3-methylpyridine and 4-methylpyridine which are impurities in mixed gas in 2, 6-dimethylpyridine, thereby realizing separation and purification of the 2, 6-dimethylpyridine. The mixed gas in the 2, 6-lutidine comprises one or two of 3-picoline and 4-picoline and the 2, 6-lutidine. Bis-diethoxy column [ n ]]The chemical structural formula of the aromatic hydrocarbon crystal material is as follows:the separation process is simple to operate and has low equipment requirement; the separation process does not need rectification operation, so that the energy consumption is low, the energy is saved, and the purification cost of the 2, 6-lutidine is reduced; the used crystal material has high stability, can be recycled, and the separation effect is not reduced.
Description
Technical Field
The application relates to the technical field of adsorption separation, in particular to a separation and purification method of 2, 6-lutidine.
Background
2, 6-lutidine is an important chemical raw material and is widely applied to the synthesis fields of pharmaceutical industry, pesticide industry, dye industry, polymer industry and the like. In particular to the field of medicine production, 2, 6-lutidine is an important raw material in the production process of medicines such as Xuemaining, oenoxine, cortisone acetate, hydrocortisone, nicotinic acid, and Bie Lin. With the rapid development of fine chemical engineering such as medicines, pesticides, dyes, rubber additives and the like, the use amount and purity requirements of the 2, 6-lutidine are increased year by year, and the improvement of production modes and purification means are key to obtaining the high-purity 2, 6-lutidine.
At present, the production modes of 2, 6-lutidine are mainly divided into two main types. The first is to extract 2, 6-lutidine from coking by-products, which is mainly to obtain pyridine compounds of various boiling ranges by vacuum distillation, however, since 2, 6-lutidine (boiling point 143.7 ℃) and 3-picoline (boiling point 143.9 ℃) differ from 4-picoline (boiling point 144.9 ℃) by only less than 1 ℃, it is difficult to separate by conventional distillation methods, and the three components in the obtained 2, 6-lutidine fraction each account for about 30%, which is difficult to purify and has high purification cost.
Another production method is chemical synthesis of 2, 6-lutidine, which usually utilizes acetone, formaldehyde and ammonia to catalyze and synthesize 2, 6-lutidine, but the method also can obtain byproducts such as 3-picoline and 4-picoline. Although more reaction paths and more accurate synthesis can be realized by utilizing the specific catalyst, the catalyst is easy to coke and deactivate, has short single-pass service life and limits the application of the method. Therefore, how to separate 3-picoline and 4-picoline with similar boiling points from the 2, 6-lutidine stock solution becomes a problem to be solved.
The patent specification with publication number of CN101066946A discloses a method for realizing normal-pressure azeotropic distillation separation of 2, 6-lutidine, 3-methylpyridine and 4-methylpyridine under the condition that two entrainers coexist, so that a high-purity product with the components of more than 99 weight percent can be obtained, but the distillation process and the subsequent entrainer removal process are accompanied by huge energy consumption.
The patent specification with publication number CN102372668A discloses a method for purifying crude 2, 6-lutidine by using urea and 2, 6-lutidine to form a complex, which greatly reduces energy consumption, but the method requires complicated operation steps and requires a lot of labor cost.
Disclosure of Invention
Aiming at the defects existing in the field and the defects of complex operation process, high labor cost, high energy consumption and the like existing in the process of obtaining high-purity 2, 6-lutidine, the application provides a separation and purification method of 2, 6-lutidine, which can selectively adsorb 3-picoline and 4-picoline impurities in 2, 6-lutidine by using a bis-diethoxy column [5] arene crystal material, has the advantages of low energy consumption and simple operation process, and the crystal material has high stability and can be recycled.
A separation and purification method of 2, 6-lutidine uses a bis-diethoxy column [5] arene crystal material as an adsorbent, and can selectively adsorb 3-picoline and 4-picoline impurities in mixed gas in the 2, 6-lutidine to realize separation and purification of the 2, 6-lutidine.
The chemical structural formula of the bis-diethoxy column [5] arene crystal material is as follows:
the application is characterized in that:
the bis-diethoxy column [5] arene crystal material can selectively adsorb 3-methylpyridine and 4-methylpyridine impurities in 2, 6-dimethylpyridine.
Under the condition of solid-gas adsorption, due to the difference of molecular structures of 2, 6-lutidine, 3-methylpyridine and 4-methylpyridine, the bisdiethoxy column [5] arene crystal material can form a host-guest complex with 3-methylpyridine and 4-methylpyridine, wherein the bisdiethoxy column [5] arene crystal material is taken as a host, 3-methylpyridine and 4-methylpyridine are taken as guests, and the stoichiometric ratio of the host to the guests in the host-guest complex is 1:2. Under the condition of solid-gas adsorption, the bis-diethoxy column [5] arene crystal material can not form a host-guest complex with 2, 6-lutidine.
The host-guest complex formed by the bis-diethoxy column [5] arene crystal material and 3-methyl pyridine and 4-methyl pyridine is unstable, and can be gradually decomplexed when heated, so that the adsorbed 3-methyl pyridine and 4-methyl pyridine are released, and desorption is realized. The bis-diethoxy column [5] arene crystal material is stable at the desorption temperature, can be reused after the desorption process is finished, and the selectivity is not reduced.
Preferably, the preparation method of the bis-diethoxy column [5] arene crystal material comprises the following steps: and (3) placing the bis-diethoxy column [5] arene in a poor solvent for recrystallization, and heating, drying and activating to obtain the bis-diethoxy column [5] arene crystal material.
Preferably, the preparation method of the bis-diethoxy column [5] arene comprises the following steps: adding p-benzene diethyl ether into 1, 2-dichloroethane, adding Lewis acid, reacting at 25-30 ℃ for 20-25 min, quenching with saturated sodium bicarbonate solution, extracting with dichloromethane, concentrating to obtain crude product, and separating by column chromatography to obtain bis-diethoxy column [5] arene.
Preferably, the poor solvent is tetrahydrofuran or acetone.
Preferably, the bis-diethoxy column [5] arene crystal material obtained by recrystallization is activated by heating to remove solvent molecules, and the activation time is not less than 4 hours.
The activated bis-diethoxy column [5] arene crystal material can be directly used for purifying mixed gas containing one or two of 3-picoline and 4-picoline and 2, 6-lutidine.
Further, the separation and purification method specifically comprises the following steps: the bis-diethoxy column [5] arene crystal material is placed in a mixed vapor atmosphere containing 2, 6-dimethylpyridine and one or two of 3-methylpyridine and 4-methylpyridine, the temperature is 20-30 ℃, and the adsorption time is changed according to the change of the sample amount, the adsorption temperature, the ratio of 3-methylpyridine in the mixture and the ratio of 4-methylpyridine in the mixture.
In the adsorption process, the crystal form of the bis-diethoxy column [5] arene crystal material can be changed. 3-picoline and 4-picoline in the mixed vapor form a host-guest complex with bis-diethoxy column [5] arene due to multiple hydrogen bonding between CH-pi and CH-O. In the host-guest complex, a bis-diethoxy column [5] arene crystal material is taken as a host, 3-methylpyridine and 4-methylpyridine are taken as guests, and the stoichiometric ratio of the host to the guest in the host-guest complex is 1:2.
Further, the separation and purification method of the 2, 6-lutidine further comprises the step of removing the mixed gas adsorbed on the surface of the adsorbent after the adsorption and separation are completed.
Preferably, the method for removing the mixed gas adsorbed on the surface of the adsorbent comprises the following steps: the mixed gas adsorbed on the surface of the bis-diethoxy column [5] arene crystal material is removed by vacuum heating or decompression heating, the heating temperature is 30-50 ℃, and the heating time is adjusted according to the sample amount.
The main guest compound is still stably present at 30-50 ℃, and the mixed gas adsorbed on the surface can be gradually removed. By removing the mixed gas adsorbed on the surface of the adsorbent, the selectivity of the adsorbent can be calibrated better.
Further, the separation and purification method of the 2, 6-lutidine further comprises the step of regenerating the adsorbent after the adsorption separation is completed.
Preferably, the method for regenerating the adsorbent comprises the following steps: under the condition of vacuum or inert atmosphere, the bis-diethoxy column [5] arene crystal material is heated to 120-140 ℃ for at least 2h and is regulated according to the sample amount.
At 120-140 deg.c, the main-guest complex formed by 3-methyl pyridine and 4-methyl pyridine in mixed vapor and bis-diethoxy column 5 arene is unstable, and the adsorbed 3-methyl pyridine and 4-methyl pyridine molecule will be released gradually while the bis-diethoxy column 5 arene crystal material is stable and only the crystal form change occurs during the desorption. The regenerated bis-diethoxy column [5] arene crystal material can be obtained after the desorption is completed, and can be continuously used for adsorbing and purifying the 2, 6-lutidine mixed gas for the next cycle.
Compared with the prior art, the application has the main advantages that: the separation process is simple to operate, and the equipment requirement is low; the separation process does not need rectification operation, so that the energy consumption is low, the energy is saved, and the purification cost of the 2, 6-lutidine is reduced; the used crystal material has high stability, can be recycled, and the separation effect is not reduced.
Drawings
FIG. 1 is a powder X-ray diffraction (PXRD) diagram of the bis-diethoxy column [5] arene crystal materials of examples 1-5;
FIG. 2 is a graph showing the results of gas chromatography characterization after the adsorption separation of 2, 6-lutidine, 3-picoline and 4-picoline mixed gas from the bis-diethoxy column [5] arene crystal material of example 3;
FIG. 3 is a graph showing the adsorption effect of the bis-diethoxy column [5] arene crystal material of example 5 on a mixture of 2, 6-lutidine, 3-methylpyridine and 4-methylpyridine when the material is recycled;
FIG. 4 is a graph showing the purification effect of the bis-diethoxy column [5] arene crystal material of example 6 on 2, 6-lutidine, 3-methylpyridine and 4-methylpyridine mixed gases of different compositions.
Detailed Description
The application will be further elucidated with reference to the drawings and to specific embodiments. It is to be understood that these examples are illustrative of the present application and are not intended to limit the scope of the present application. The experimental methods, in which specific conditions are not noted in the following examples, are generally conducted under conventional conditions or under conditions recommended by the manufacturer.
Example 1
Preparation of bis-diethoxy column [5] arene crystal material: adding p-benzene diethyl ether into 1, 2-dichloroethane, adding Lewis acid, reacting at 25-30 ℃ for 20-25 min, quenching with saturated sodium bicarbonate solution, extracting with dichloromethane, concentrating to obtain crude product, and separating by column chromatography to obtain bis-diethoxy column [5] arene. 2g of bis-diethoxy column [5] arene is weighed and placed in 20mL of tetrahydrofuran, heated to boiling, tetrahydrofuran solution is added dropwise until all the solution is dissolved, the solution is placed at 0 ℃ for storage overnight, the precipitated crystals are collected by filtration, and the obtained crystals are dried in vacuum at 50 ℃ to obtain white powder which is recorded as EtP.
The product characterization data prepared in this example are as follows:
EtP5，1H NMR(500MHz，CDCl3，298K，ppm)δ6.72(s，10H)，3.83(q，20H)，3.76(s，10H)，1.55(t，30H)。
and (3) performing PXRD characterization on the activated bis-diethoxy column [5] arene crystal material, wherein a PXRD detection result is shown in a figure 1, and the obtained bis-diethoxy column [5] arene crystal material has good crystallinity.
Example 2
Adsorption of bis-diethoxy column [5] arene crystal material to 2, 6-lutidine or 3-picoline or 4-picoline alone: three 20mL strain bottles were taken, 1mL of 2, 6-lutidine, 1mL of 3-picoline and 1mL of 4-picoline were added, respectively designated as EtP5-2,6-DMP, etP5-3-MP and EtP5-4-MP, 200mg of bis-diethoxy column [5] arene crystal material was placed in two 5mL strain bottles, respectively, two open 5mL strain bottles were placed in two 20mL strain bottles, the 20mL strain bottles were sealed, and placed in a 25℃water bath for 30 hours.
The crystalline material of bis-diethoxy column [5] arene is characterized after being placed in a vapor atmosphere of 2, 6-lutidine or 3-picoline or 4-picoline for a period of time.
The product characterization data prepared in this example are as follows:
EtP5-2,6-DMP,1H NMR(500MHz,CDCl3,298K,ppm)δ6.72(s,10H),3.83(q,20H),3.76(s,10H),1.55(t,30H)。
EtP5-3-MP,1H NMR(500MHz,CDCl3,298K,ppm)δ8.45(s,1H),8.42(d,1H),7.48(d,1H),7.18(q,1H),6.72(s,10H),3.83(q,20H),3.76(s,10H),2.33(s,3H)1.55(t,30H)。
EtP5-4-MP,1H NMR(500MHz,CDCl3,298K,ppm)δ8.46(d,2H),7.10(d,2H),6.72(s,10H),3.83(q,20H),3.76(s,10H),2.34(s,3H),1.55(t,30H)。
the 1H NMR results showed that: 3-methyl pyridine and 4-methyl pyridine are adsorbed by the bis-diethoxy column [5] arene crystal material, and the stoichiometric ratio of the bis-diethoxy column [5] arene crystal material is 1:2, wherein 3-methylpyridine is adsorbed by the mode, and the stoichiometric ratio of the bis-diethoxy column [5] arene crystal material is 1:2 to adsorb 4-methylpyridine; the bis-diethoxy column [5] arene crystal material has no adsorption to 2, 6-dimethyl pyridine.
The PXRD measurements are shown in fig. 1, and the PXRD patterns of the bis-diethoxy column [5] arene crystal material after a period of time in 3-picoline vapor and the bis-diethoxy column [5] arene crystal material after a period of time in 4-picoline vapor are changed relative to the PXRD patterns of the initially activated bis-diethoxy column [5] arene crystal material, which indicates that their unit cell parameters have changed, meaning that 3-picoline and 4-picoline have been adsorbed into the bis-diethoxy column [5] arene crystal material, respectively; the spectrogram of the bis-diethoxy column [5] arene crystal material after being placed in 2, 6-lutidine vapor for a period of time has little change, which indicates that the unit cell parameters of the bis-diethoxy column [5] arene crystal material have no change, and the bis-diethoxy column [5] arene crystal material has no adsorption capacity to 2, 6-lutidine.
Example 3
Adsorption of bis-diethoxy column [5] arene crystal material to a mixture of 2, 6-lutidine, 3-picoline and 4-picoline, wherein the volume ratio of 2, 6-lutidine, 3-picoline and 4-picoline is 50:25:25: a20 mL strain bottle was taken, 0.5mL of 2, 6-lutidine, 0.25mL of 3-picoline and 0.25mL of 4-picoline were added, designated EtP-MIX, 200mg of bis-diethoxy column [5] arene crystal material was placed in a 5mL strain bottle, the open 5mL strain bottle was placed in the above 20mL strain bottle, the 20mL strain bottle was sealed, placed in a 25℃water bath for 40 hours, and the resulting powder was placed in a vacuum oven at 50℃for 30 minutes.
The crystalline material of bis-diethoxy column [5] arene is characterized after being placed in a mixed vapor atmosphere of 2, 6-lutidine, 3-picoline and 4-picoline for a period of time.
The product characterization data prepared in this example are as follows:
EtP5-MIX,1H NMR(500MHz,CDCl3,298K,ppm)δ8.46(d,2H),8.45(s,1H),8.42(d,1H),7.48(d,1H),7.18(q,1H),7.10(d,2H),6.72(s,10H),3.83(q,20H),3.76(s,10H),2.34(s,3H),2.33(s,3H),1.55(t,30H)。
only the signals of the hydrogen atoms corresponding to both 3-picoline and 4-picoline are found in the 1H NMR spectrum, which shows that the bis-diethoxy column [5] arene crystal material can selectively adsorb 3-picoline and 4-picoline which are impurities in 2, 6-lutidine.
The PXRD detection results are shown in fig. 1, and the PXRD spectrum of the bis-diethoxy column [5] arene crystal material after a period of time in the mixed vapor of 2, 6-lutidine, 3-methylpyridine and 4-methylpyridine is changed relative to the PXRD spectrum of the initially activated bis-diethoxy column [5] arene crystal material, and the spectrum change is the same as EtP5-3-MP or EtP-4-MP, which indicates that the bis-diethoxy column [5] arene crystal material can selectively adsorb 3-methylpyridine and 4-methylpyridine as impurities in 2, 6-lutidine.
The results of headspace gas chromatography are shown in fig. 2, and the results show that the bis-diethoxy column [5] arene crystal material can selectively adsorb 3-methylpyridine and 4-methylpyridine as impurities in 2, 6-dimethylpyridine, and the selectivity is 96.72%.
Example 4
Regeneration of bis-diethoxy column [5] arene crystal material: the bis-diethoxy column [5] arene crystal material was placed in a mixed vapor of 2, 6-lutidine, 3-methylpyridine and 4-methylpyridine for a period of time and saturated. 200mg of saturated adsorbed bis-diethoxy column [5] arene crystal material was heated in a vacuum oven at 140℃for 2 hours, and the sample was designated EtP5-D1.
Characterization is carried out on the desorbed bis-diethoxy column [5] arene crystal material.
The product characterization data prepared in this example are as follows:
EtP5-D1,1H NMR(500MHz,CDCl3,298K,ppm)δ6.72(s,10H),3.83(q,20H),3.76(s,10H),1.55(t,30H)。
the signals of the hydrogen atoms corresponding to the 3-picoline and the 4-picoline are found to be disappeared in the 1H NMR spectrum, which indicates that the bisdiethoxy column [5] arene crystal material has completed desorption regeneration, and the 3-picoline and the 4-picoline molecules have been completely released.
The PXRD detection results are shown in fig. 1, and the PXRD spectrum of the desorbed bis-diethoxy column [5] arene crystal material has little change compared with the PXRD spectrum of the initially activated bis-diethoxy column [5] arene crystal material, which indicates that the bis-diethoxy column [5] arene crystal material has completed the desorption process.
Example 5
The bis-diethoxy column [5] arene crystal material is recycled: 200mg of the regenerated bis-diethoxy column [5] arene crystal material was subjected to the repetition of examples 3 and 4. Wherein, the bis-diethoxy column [5] arene crystal material after 5 times of cyclic desorption is recorded as EtP5-D5.
Characterization is carried out on the desorbed bis-diethoxy column [5] arene crystal material.
The product characterization data prepared in this example are as follows:
FIG. 3 is a graph showing the adsorption effect of the bis-diethoxy column [5] arene crystal material when it is recycled. The result shows that the bis-diethoxy column [5] arene crystal material can selectively adsorb 3-methyl pyridine and 4-methyl pyridine, the selectivity is as high as 96.72%, and the selectivity is not obviously reduced when the bis-diethoxy column [5] arene crystal material is repeatedly used for 5 times.
The PXRD detection results are shown in fig. 1, and the PXRD spectrum of the desorbed bis-diethoxy column [5] arene crystal material has little change relative to the PXRD spectrum of the initially activated bis-diethoxy column [5] arene crystal material, which indicates that the bis-diethoxy column [5] arene crystal material has completed the desorption process, and fully demonstrates the excellent structural stability of the bis-diethoxy column [5] arene crystal material.
Example 6
Bis-diethoxy column [5] arene crystal material purification of 2, 6-lutidine, 3-picoline and 4-picoline mixtures of different composition: three groups of mixed solutions (1), (2) and (3) with different proportions are prepared in advance, six 20mL strain bottles A, B, C, a, b, c are taken, wherein A, B, C is an experimental group, and a, b and c are control groups. 0.1mL of the mixed solution (1) was added to the A and a strain bottles, wherein the volume ratio of 2, 6-lutidine, 3-picoline and 4-picoline was about 50:25:25. Into the B and B strain bottles, 0.1mL of the mixed solution (2) was added, wherein the volume ratio of 2, 6-lutidine, 3-picoline and 4-picoline was about 80:10:10. Into the C and C strain bottles, 0.1mL of the mixed solution (3) was added, wherein the volume ratio of 2, 6-lutidine, 3-picoline and 4-picoline was about 90:5:5. Then 400mg of the bis-diethoxy column [5] arene crystal material prepared in example 1 was placed in three 5mL strain bottles, each of which was placed in the 20mL strain bottle A, B, C, and the six 20mL strain bottles were sealed, and were placed at room temperature of 25℃for 48 hours, and the concentration of each component in the six strain bottles was measured.
The bis-diethoxy column [5] arene crystal materials were characterized after being placed in a mixed vapor atmosphere of 2, 6-lutidine, 3-picoline and 4-picoline of different compositions for a period of time.
The detection result of the headspace gas chromatography is shown in figure 4, and the result shows that the bis-diethoxy column [5] arene crystal material can selectively adsorb 3-methylpyridine and 4-methylpyridine in mixed solutions with different volume ratios. In the experimental group with the volume ratio of 2, 6-lutidine, 3-picoline and 4-picoline being about 50:25:25, the volume ratio of 2, 6-lutidine to impurities (3-picoline and 4-picoline) after the absorption of the bis-diethoxy column [5] arene crystal material is 90.97:9.03; in the experimental group with the volume ratio of 2, 6-lutidine, 3-picoline and 4-picoline being about 80:10:10, the volume ratio of 2, 6-lutidine to impurities (3-picoline and 4-picoline) after the absorption of the bis-diethoxy column [5] arene crystal material is 93.51:6.49; in the experimental group with the volume ratio of 2, 6-lutidine, 3-picoline and 4-picoline being about 90:5:5, the volume ratio of 2, 6-lutidine to impurities (3-picoline and 4-picoline) after adsorption of the bis-diethoxy column [5] arene crystal material was 94.89:5.11.
Further, it is to be understood that various changes and modifications of the present application may be made by those skilled in the art after reading the above description of the application, and that such equivalents are intended to fall within the scope of the application as defined in the appended claims.
Claims (6)
1. A separation and purification method of 2, 6-lutidine is characterized in that a bis-diethoxy column [5] arene crystal material is used as an adsorbent, 3-picoline and 4-picoline impurities in mixed gas in 2, 6-lutidine can be selectively adsorbed, and separation and purification of 2, 6-lutidine are realized;
the mixed gas in the 2, 6-lutidine comprises one or two of 3-picoline and 4-picoline and 2, 6-lutidine;
the chemical structural formula of the bis-diethoxy column [5] arene crystal material is as follows:
；
the separation and purification method specifically comprises the following steps: placing a bis-diethoxy column [5] arene crystal material in a mixed vapor atmosphere containing 2, 6-lutidine and one or two of 3-picoline and 4-picoline, wherein the temperature is 20-30 ℃;
the separation and purification method also comprises the step of removing the mixed gas adsorbed on the surface of the adsorbent after the adsorption and separation are completed; the method for removing the mixed gas adsorbed on the surface of the adsorbent comprises the following steps: and removing the mixed gas adsorbed on the surface of the bis-diethoxy column [5] arene crystal material by vacuum heating or reduced pressure heating, wherein the heating temperature is 30-50 ℃.
2. The method for separating and purifying 2, 6-lutidine according to claim 1, wherein the preparation method of the bis-diethoxy column [5] arene crystal material is as follows: and (3) placing the bis-diethoxy column [5] arene in a poor solvent for recrystallization, and heating, drying and activating to obtain the bis-diethoxy column [5] arene crystal material.
3. The method for preparing the bis-diethoxy column [5] arene crystal material according to claim 2, wherein the method for preparing the bis-diethoxy column [5] arene is as follows: and adding p-phenethyl ether into 1, 2-dichloroethane, adding Lewis acid, reacting for 20-25 min at 25-30 ℃, then quenching with saturated sodium bicarbonate solution, extracting with dichloromethane, concentrating to obtain a crude product, and separating by column chromatography to obtain the bis-diethoxy column [5] arene.
4. The method for preparing the bis-diethoxy column [5] arene crystal material according to claim 2, characterized in that:
the poor solvent is tetrahydrofuran or acetone;
the activation time of the activation is not less than 4h.
5. The separation and purification method according to claim 1, further comprising regeneration of the adsorbent after the completion of the adsorption separation.
6. The separation and purification method according to claim 5, wherein the method for regenerating the adsorbent comprises: and heating the bis-diethoxy column [5] arene crystal material to 120-140 ℃ under the vacuum or inert atmosphere condition, wherein the heating time is not less than 2 h.
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| CN202210505371.XA CN114773258B (en) | 2022-05-10 | 2022-05-10 | Separation and purification method of 2, 6-lutidine |
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| CN202210505371.XA CN114773258B (en) | 2022-05-10 | 2022-05-10 | Separation and purification method of 2, 6-lutidine |
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| CN101066946A (en) * | 2007-06-01 | 2007-11-07 | 华东理工大学 | Process of separating methyl pyridine mixture |
| CN110092706A (en) * | 2019-05-07 | 2019-08-06 | 浙江大学 | A kind of separation method of p-chlorotoluene and ortho-chlorotolu'ene |
| CN110372580A (en) * | 2019-06-20 | 2019-10-25 | 浙江大学 | A kind of separation method of 2- chloropyridine and 3- chloropyridine |
| CN111362774A (en) * | 2020-03-03 | 2020-07-03 | 浙江大学 | Application of ethoxy column [6] arene crystal material in selective adsorption of heterocyclic compound |
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| CN101066946A (en) * | 2007-06-01 | 2007-11-07 | 华东理工大学 | Process of separating methyl pyridine mixture |
| CN110092706A (en) * | 2019-05-07 | 2019-08-06 | 浙江大学 | A kind of separation method of p-chlorotoluene and ortho-chlorotolu'ene |
| CN110372580A (en) * | 2019-06-20 | 2019-10-25 | 浙江大学 | A kind of separation method of 2- chloropyridine and 3- chloropyridine |
| CN111362774A (en) * | 2020-03-03 | 2020-07-03 | 浙江大学 | Application of ethoxy column [6] arene crystal material in selective adsorption of heterocyclic compound |
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