CN111848355B - Method for extracting n-borneol from turpentine oil isomerization reaction liquid - Google Patents
Method for extracting n-borneol from turpentine oil isomerization reaction liquid Download PDFInfo
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- CN111848355B CN111848355B CN202010697979.8A CN202010697979A CN111848355B CN 111848355 B CN111848355 B CN 111848355B CN 202010697979 A CN202010697979 A CN 202010697979A CN 111848355 B CN111848355 B CN 111848355B
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- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/74—Separation; Purification; Use of additives, e.g. for stabilisation
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/74—Separation; Purification; Use of additives, e.g. for stabilisation
- C07C29/76—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment
- C07C29/78—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment by condensation or crystallisation
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- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/74—Separation; Purification; Use of additives, e.g. for stabilisation
- C07C29/76—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment
- C07C29/80—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment by distillation
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- C07C2601/12—Systems containing only non-condensed rings with a six-membered ring
- C07C2601/16—Systems containing only non-condensed rings with a six-membered ring the ring being unsaturated
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- C07—ORGANIC CHEMISTRY
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- C07C2602/00—Systems containing two condensed rings
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Abstract
The invention relates to a method for extracting borneol from turpentine oil isomerization reaction liquid. Specifically, the invention provides a method for extracting borneol from turpentine isomerization reaction liquid, which comprises the following steps: providing turpentine oil isomerization reaction liquid; (2) The turpentine oil isomerization reaction liquid enters a first rectifying tower for rectification, camphene is extracted from the tower top of the first rectifying tower, tower still materials of the first rectifying tower are transferred to a second rectifying tower for rectification, dipentene is extracted from the tower top of the second rectifying tower, tower still materials of the second rectifying tower are transferred to a third rectifying tower for rectification, and naphtha is extracted from the tower top of the third rectifying tower; (3) Crystallizing borneol oil at 5-12 deg.C, centrifuging to obtain crude borneol, dissolving the crude borneol in organic solvent, crystallizing at room temperature, and separating to obtain normal borneol. The method can effectively extract the n-borneol which is a byproduct of turpentine oil isomerization reaction liquid, and the extracted n-borneol has excellent purity.
Description
Technical Field
The invention relates to the field of pharmaceutical chemicals, and particularly relates to a method for extracting borneol from turpentine oil isomerization reaction liquid.
Background
Borneol (Borneol) has great medical value, has remarkable effects in many aspects such as antibiosis, anti-inflammation, pain relieving, antifertility and the like, and is taken as one of main composition medicaments by many Chinese patent medicaments, such as Bingpeng powder, bezoar antitoxic pill, angongniuhuang pill, bezoar supernatant pill, storax pill and the like.
The borneol has two epimers of normal borneol and isoborneol, however, the side effect of isoborneol is far greater than that of normal borneol, and the resource of normal borneol is very limited, so that the price of normal borneol is much more expensive than that of isoborneol, and the price of normal borneol is high, so that the increasing needs of human beings are greatly limited, therefore, how to further improve the utilization value of normal borneol becomes the hotspot of current research.
In the production process of camphor, turpentine needs to be subjected to isomerization reaction, and isomerization reaction liquid mainly contains camphene and dipentene, but also contains byproducts such as n-borneol, isoborneol, longifolene and the like. However, in the existing turpentine oil isomerization process, byproducts such as normal borneol, isoborneol, longifolene and the like are treated as low-value distillation still residues, so that the waste of normal borneol is greatly caused, and the waste of medical resources is caused.
Therefore, there is a need in the art to develop a method for extracting borneol from turpentine isomerization reaction liquid, so as to effectively recycle borneol and avoid waste of medical resources.
Disclosure of Invention
The invention aims to provide a method for effectively extracting n-borneol which is a byproduct of turpentine isomerization reaction liquid, and the n-borneol with excellent purity is prepared, so that the n-borneol is prevented from being wasted as waste.
In one aspect of the present invention, there is provided a method for extracting n-borneol from turpentine isomerization reaction liquid, the method comprising the steps of:
(1) Providing turpentine oil isomerization reaction liquid;
(2) The turpentine oil isomerization reaction liquid enters a first rectifying tower for rectification, camphene is extracted from the tower top of the first rectifying tower, tower still materials of the first rectifying tower are transferred to a second rectifying tower for rectification, dipentene is extracted from the tower top of the second rectifying tower, tower still materials of the second rectifying tower are transferred to a third rectifying tower for rectification, and naphtha is extracted from the tower top of the third rectifying tower;
(3) Crystallizing the borneol oil at 5-12 ℃, performing centrifugal separation to obtain crude borneol, dissolving the crude borneol in an organic solvent, crystallizing at room temperature, and separating to obtain the borneol.
Preferably, the turpentine oil isomerization reaction liquid is prepared by the following method:
and (1-1) reacting the turpentine under the catalysis of metatitanic acid to generate turpentine isomerization reaction liquid.
Preferably, in the step (1-1), the metatitanic acid is 0.5-1.5wt%, preferably 0.8-1.2wt% of the turpentine.
Preferably, in the step (1-1), the reaction temperature is 100-120 ℃.
Preferably, in the step (1-1), the reaction time is 15-20h, preferably 15-17h.
Preferably, the rectification in the first rectification tower is continuous rectification or batch rectification.
Preferably, in the step (2), the rectification in the first rectification column is performed under one or more characteristics selected from the group consisting of:
the temperature of the tower kettle is 100-120 ℃;
the vacuum degree at the tower top is 90-100Kpa;
the absolute value difference between the vacuum degrees of the tower top and the tower kettle is 10-15Kpa;
the discharge amount is 800-1200Kg/h; and/or
The reflux ratio is 2-4:1.
Preferably, the rectification in the second rectification tower is continuous rectification or batch rectification.
Preferably, in the step (2), the rectification in the second rectification column is performed under one or more characteristics selected from the group consisting of:
the temperature of the tower kettle is 125-140 ℃;
the vacuum degree at the tower top is 90-100Kpa;
the absolute value difference between the vacuum degrees of the tower top and the tower kettle is 10-15Kpa;
the discharge amount is 200-300Kg/h; and/or
The reflux ratio is 2-3:1.
Preferably, the rectification in the third rectifying tower is continuous rectification or batch rectification.
Preferably, in the step (2), the rectification in the third rectification column is performed under one or more characteristics selected from the group consisting of:
the temperature of the tower kettle is 130-150 ℃;
the temperature in the tower is 100-120 ℃;
the temperature at the top of the tower is 40-60 ℃;
the vacuum degree at the tower top is 90-110Kpa;
the absolute value difference between the vacuum degrees of the tower top and the tower kettle is 10-15Kpa;
the discharge amount is 50-70Kg/h; and/or
The reflux ratio is 3-5:1.
Preferably, the temperature of the naphtha is maintained at 70-80 ℃ while the naphtha is withdrawn from the third rectification column.
Preferably, in the step (2), the distillation is carried out in the third distillation column, and the reflux ratio is controlled to be 3-5:1 when the naphtha is extracted.
Preferably, the distillation is carried out in the third rectifying tower, and when the naphtha is produced, the temperature of a discharge pipe needs to be kept at 70-80 ℃, so that the temperature of the produced naphtha is 70-80 ℃.
Preferably, in the step (3), the borneol oil is crystallized at 6-10 ℃.
Preferably, in the step (3), the organic solvent is C7-C9 alkane.
Preferably, the C7-C9 alkane is heptane.
Preferably, the heptane is n-heptane.
Preferably, the weight ratio of the crude borneol to the organic solvent (such as n-heptane) is 1.
Preferably, in the step (3), in the mixed solution of crude borneol and organic solvent, the weight ratio of the crude borneol to the organic solvent is 1.3-1.7.
Preferably, the temperature of the organic solvent is 85 to 95 ℃, preferably 88 to 92 ℃.
Preferably, in the step (3), the room temperature is 15-35 ℃, preferably 18-22 ℃.
Preferably, in the step (3), the crude borneol is dissolved in an organic solvent, and then the crude borneol is naturally cooled to room temperature and crystallized.
Preferably, in the step (3), the crystallization is performed at room temperature for 5 to 7 days, preferably 5.5 to 6.5 days.
Preferably, in the step (3), after crystallization at room temperature, normal borneol is obtained after separation and drying.
It is to be understood that within the scope of the present invention, the above-described features of the present invention and those specifically described below (e.g., in the examples) may be combined with each other to form new or preferred embodiments.
Detailed Description
The invention discloses a method for extracting borneol from turpentine oil isomerization reaction liquid, which comprises the steps of rectifying the turpentine oil isomerization reaction liquid and crystallizing the extracted borneol oil to obtain the high-purity borneol. The method can effectively extract the n-borneol which is a byproduct of turpentine oil isomerization reaction liquid, and the extracted n-borneol has excellent purity.
Term(s) for
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.
As used herein, the terms "comprising," "including," and "containing" are used interchangeably and include not only open-ended definitions, but also semi-closed and closed-ended definitions, and include "consisting of … …" and "consisting essentially of … …".
The invention provides a method for extracting borneol from turpentine oil isomerization reaction liquid, which comprises the following steps:
(1) Providing turpentine oil isomerization reaction liquid;
(2) The turpentine oil isomerization reaction liquid enters a first rectifying tower for rectification, camphene is extracted from the tower top of the first rectifying tower, tower still materials of the first rectifying tower are transferred to a second rectifying tower for rectification, dipentene is extracted from the tower top of the second rectifying tower, tower still materials of the second rectifying tower are transferred to a third rectifying tower for rectification, and naphtha is extracted from the tower top of the third rectifying tower;
(3) Crystallizing the borneol oil at 5-12 deg.C (preferably 6-10 deg.C), centrifuging to obtain crude borneol, dissolving the crude borneol in organic solvent, crystallizing at room temperature, and separating to obtain normal borneol.
In a preferred embodiment of the present invention, the rectification in the first, second and/or third rectification column is continuous or batch rectification.
In a preferred embodiment of the present invention, the turpentine isomerization reaction liquid is prepared by the following method:
and (1-1) reacting the turpentine under the catalysis of metatitanic acid to generate turpentine isomerization reaction liquid.
In another preferred mode of the present invention, the rectification in the first rectification column is performed under the condition including one or more characteristics selected from the group consisting of:
the temperature of the tower kettle is 100-120 ℃;
the vacuum degree at the tower top is 90-100Kpa;
the absolute value difference between the vacuum degrees of the tower top and the tower kettle is 10-15Kpa;
the discharge amount is 800-1200Kg/h; and/or
The reflux ratio is 2-4:1.
In another preferred mode of the present invention, the rectification in the second rectification column is performed under one or more characteristics selected from the group consisting of:
the temperature of the tower kettle is 125-140 ℃;
the vacuum degree at the tower top is 90-100Kpa;
the absolute value difference between the vacuum degrees of the tower top and the tower kettle is 10-15Kpa;
the discharge amount is 200-300Kg/h; and/or
The reflux ratio is 2-3:1.
In another preferred mode of the present invention, the rectification in the third rectification column is performed under one or more characteristics selected from the group consisting of:
the temperature of the tower kettle is 130-150 ℃;
the temperature in the tower is 100-120 ℃;
the temperature at the top of the tower is 40-60 ℃;
the vacuum degree at the top of the tower is 90-110Kpa;
the absolute value difference between the vacuum degrees of the tower top and the tower kettle is 10-15Kpa;
the discharge amount is 50-70Kg/h; and/or
The reflux ratio is 3-5:1.
In another preferred embodiment of the present invention, in the step (3), the organic solvent is a C7-C9 alkane. For example heptane (e.g. n-heptane).
In another preferred embodiment of the invention, in the mixed solution of crude borneol and organic solvent, the weight ratio of the crude borneol to the organic solvent is 1.3-1.7.
The main technical effects of the invention comprise:
the invention develops the method which can effectively extract the by-product of the turpentine oil isomerization reaction liquid, namely the borneol has excellent purity, thereby avoiding the waste of the borneol serving as a low-value by-product, saving medical resources and improving the application value of the borneol.
The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention.
Example 1
(1) Adding metatitanic acid into turpentine, wherein the metatitanic acid accounts for 1wt% of the weight of turpentine, reacting for 16h at 110 ℃ to obtain reaction liquid, and the main products in the reaction liquid are camphene and dipentene and contain heavy parts such as n-borneol, isobornene and longifolene.
(2) The reaction liquid obtained in the step (1) enters a rectifying tower A to be continuously rectified by a pump (the temperature of a tower kettle of the rectifying tower A is 110 ℃, the vacuum degree of the tower top is 92Kpa, the absolute value difference of the vacuum degrees of the tower top and the tower kettle is 12Kpa, the discharge amount is 1000Kg/h, the reflux ratio is 3:1), camphene is extracted from the tower top of the tower A, the tower kettle material of the tower A is transferred to a rectifying tower B matched with the rectifying tower A to be continuously rectified (the temperature of the tower kettle of the rectifying tower B is 130 ℃, the vacuum degree of the tower top is 92Kpa, the absolute value difference of the vacuum degrees of the tower top and the tower kettle is 12Kpa, the discharge amount is 250Kg/h, and the reflux ratio is 2.5): and (2) extracting dipentene from the tower top of the tower B, transferring the tower bottom material of the tower B into a rectifying tower C for intermittent rectification (the tower bottom temperature of the rectifying tower C is 140 ℃, the temperature in the tower is controlled at 110 ℃, the tower top temperature is controlled at 50 ℃, the tower top vacuum degree of the tower top is 92Kpa, and the absolute value difference of the tower top vacuum degree and the tower bottom vacuum degree is 12 Kpa), and extracting borneol oil from the tower top of the tower C, wherein the discharge amount is controlled to prevent pipeline blockage when extracting borneol oil, the discharge amount is controlled at 60Kg/h, the reflux ratio is controlled at 4:1, the discharge pipe is required to be insulated at 75 ℃, and the borneol oil is prevented from being crystallized and separated out partially, so that the borneol oil at 75 ℃ is obtained.
(3) Crystallizing the borneol oil obtained in the step (2) at 8 ℃, then carrying out centrifugal separation to obtain precipitated crude borneol, dissolving the crude borneol in 90 ℃ n-heptane (the weight ratio of the crude borneol to the n-heptane is 1.
Example 2
This example is similar to example 1, except that in the step (2), when naphtha is taken out from the fractionator C, the reflux ratio is controlled to 2:1, and the purity of the obtained normal borneol crystal is 85.7%.
Example 3
This example is the same as example 1 except that in the step (3), precipitated crude borneol was dissolved in ethanol at 60 ℃ to obtain borneol crystals with a purity of 81.7%.
Example 4
This example is the same as example 1 except that in the step (3), precipitated crude borneol was dissolved in chloroform at 50 ℃ to obtain borneol crystals having a purity of 75.6.1%.
Example 5
This example is the same as example 1 except that in the step (3), the weight ratio of crude borneol to n-heptane was 1:1, and the purity of the obtained n-borneol crystal was 87.3%.
Example 6
This example is the same as example 1, except that in the step (3), after the borneol oil obtained in the step (2) was crystallized at 16 ℃, the purity of the obtained n-borneol crystal was 87.1%.
The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims (10)
1. A method for extracting borneol from turpentine oil isomerization reaction liquid is characterized by comprising the following steps:
(1) Providing turpentine oil isomerization reaction liquid;
(2) The turpentine oil isomerization reaction liquid enters a first rectifying tower for rectification, camphene is extracted from the tower top of the first rectifying tower, tower still materials of the first rectifying tower are transferred to a second rectifying tower for rectification, dipentene is extracted from the tower top of the second rectifying tower, tower still materials of the second rectifying tower are transferred to a third rectifying tower for rectification, and naphtha is extracted from the tower top of the third rectifying tower;
(3) Crystallizing the borneol oil at 5-12 ℃, performing centrifugal separation to obtain crude borneol, dissolving the crude borneol in an organic solvent, crystallizing at room temperature, and separating to obtain normal borneol;
in the step (2), the third rectifying tower is rectified, and when naphtha is extracted, the reflux ratio is controlled to be 3-5:1;
in the step (3), the organic solvent is n-heptane;
in the step (3), in the mixed solution of crude borneol and organic solvent, the weight ratio of the crude borneol to the organic solvent is 1.
2. The method according to claim 1, wherein in the step (1), the turpentine isomerization reaction liquid is prepared by the following method:
and (1-1) reacting the turpentine under the catalysis of metatitanic acid to generate turpentine isomerization reaction liquid.
3. The method according to claim 1, wherein in step (2), the distillation in the first distillation column is performed under one or more characteristics selected from the group consisting of:
the temperature of the tower kettle is 100-120 ℃;
the vacuum degree at the tower top is 90-100Kpa;
the absolute value difference between the vacuum degrees of the tower top and the tower kettle is 10-15Kpa;
the discharge amount is 800-1200Kg/h; and/or
The reflux ratio is 2-4:1.
4. The method according to claim 1, wherein in the step (2), the rectification in the second rectification column is performed under one or more characteristics selected from the group consisting of:
the temperature of the tower kettle is 125-140 ℃;
the vacuum degree at the tower top is 90-100Kpa;
the absolute value difference between the vacuum degrees of the tower top and the tower kettle is 10-15Kpa;
the discharge amount is 200-300Kg/h; and/or
The reflux ratio is 2-3:1.
5. The method according to claim 1, wherein in the step (2), the rectification in the third rectification column is performed under one or more characteristics selected from the group consisting of:
the temperature of the tower kettle is 130-150 ℃;
the temperature in the tower is 100-120 ℃;
the temperature at the top of the tower is 40-60 ℃;
the vacuum degree at the tower top is 90-110Kpa;
the absolute value difference between the vacuum degrees of the tower top and the tower kettle is 10-15Kpa; and/or
The discharge amount is 50-70Kg/h.
6. The method according to claim 2, wherein in the step (1-1), the metatitanic acid is 0.5 to 1.5wt% based on the weight of the turpentine.
7. The method according to claim 2, wherein in the step (1-1), the metatitanic acid is 0.8 to 1.2wt% based on the weight of the turpentine.
8. The method according to claim 2, wherein the reaction temperature in step (1-1) is 100-120 ℃.
9. The method of claim 2, wherein in step (1-1), the reaction time is 15-20h.
10. The method of claim 2, wherein in step (1-1), the reaction time is 15-17h.
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