CN107892640B - Preparation method for preparing camphene by alpha-pinene isomerization - Google Patents

Preparation method for preparing camphene by alpha-pinene isomerization Download PDF

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CN107892640B
CN107892640B CN201710398997.4A CN201710398997A CN107892640B CN 107892640 B CN107892640 B CN 107892640B CN 201710398997 A CN201710398997 A CN 201710398997A CN 107892640 B CN107892640 B CN 107892640B
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camphene
pinene
alpha
distillation tower
catalyst
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CN107892640A (en
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朱庆兵
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Huaiji Changlin Chemical Co ltd
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Huaiji Changlin Chemical Co ltd
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    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C5/00Preparation of hydrocarbons from hydrocarbons containing the same number of carbon atoms
    • C07C5/22Preparation of hydrocarbons from hydrocarbons containing the same number of carbon atoms by isomerisation
    • C07C5/27Rearrangement of carbon atoms in the hydrocarbon skeleton
    • C07C5/2729Changing the branching point of an open chain or the point of substitution on a ring
    • C07C5/2732Catalytic processes
    • C07C5/2737Catalytic processes with crystalline alumino-silicates, e.g. molecular sieves
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C7/00Purification; Separation; Use of additives
    • C07C7/005Processes comprising at least two steps in series
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C7/00Purification; Separation; Use of additives
    • C07C7/04Purification; Separation; Use of additives by distillation
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C2529/00Catalysts comprising molecular sieves
    • C07C2529/04Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites, pillared clays
    • C07C2529/06Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
    • C07C2529/40Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of the pentasil type, e.g. types ZSM-5, ZSM-8 or ZSM-11

Abstract

The invention discloses a preparation method for preparing camphene by alpha-pinene isomerism, which comprises the following operation steps: the method comprises the following steps: placing a reaction raw material containing alpha-pinene into a reaction distillation tower, adding a catalyst into the distillation tower, heating a tower kettle of the reaction distillation tower, catalyzing and isomerizing the alpha-pinene under the action of the catalyst to form camphene, arranging a synthetic molecular sieve catalyst on the top of a liquid level formed by the alpha-pinene, and reacting to obtain camphene mother liquor; step two: putting the obtained camphene mother liquor into a first distillation tower, and distilling and separating tricyclene in the camphene mother liquor at the tower top of the first distillation tower; step three: and (4) putting the camphene mother liquor treated in the step (II) into a second distillation tower, and distilling and separating camphene at the tower top of the second distillation tower to obtain high-purity camphene. The preparation method for preparing camphene by alpha-pinene isomerization aims at solving the problems of low camphene content and slow reaction rate in the final product in the existing camphene preparation method.

Description

Preparation method for preparing camphene by alpha-pinene isomerization
Technical Field
The invention relates to the technical field of camphene preparation processes, in particular to a preparation method for preparing camphene by alpha-pinene isomerism.
Background
Camphene is synthesized through pinene isomerization, at present, camphene is generally a common-grade camphene product produced through pinene isomerization synthesis at home and abroad, the camphene content is more than or equal to 96 percent (containing camphene and tricyclene + camphene), and the camphene content is about 80 to 83 percent, mainly because the existing camphene distillation mainly adopts a one-time distillation mode, and tricyclene or other analogues are easy to mix in the camphene distillation process. With the development of social market, the camphene product is not only an intermediate for synthesizing camphor in the prior production, but also a high-quality camphene product is required particularly in the fields of spices, medicines, foods and the like, and the camphene content is required to be more than 98 percent, so that the product with the camphene content of more than or equal to 98 percent is difficult to produce in batch by the existing production process.
On the other hand, the sufficient degree of the reaction of the pinene and the catalyst is also an important factor influencing the camphene content in the final product, and most of the existing camphene preparation methods directly mix and heat the pinene and the catalyst, so that the reaction rate is high.
Disclosure of Invention
Aiming at the problems of low camphene content and slow reaction rate in the final product in the existing camphene preparation method, the invention discloses a preparation method for preparing camphene by alpha-pinene isomerization.
A preparation method for preparing camphene by alpha-pinene isomerization comprises the following operation steps:
the method comprises the following steps: placing a reaction raw material containing alpha-pinene in a reaction distillation tower, wherein a catalyst is put into the distillation tower, the catalyst is immersed below the liquid level formed by the alpha-pinene, heating a tower kettle of the reaction distillation tower, the alpha-pinene is catalyzed and isomerized to form camphene under the action of the catalyst, part of the alpha-pinene is evaporated and ascended, a cooling device is arranged at the top of the reaction distillation tower, the evaporated alpha-pinene is condensed and refluxed, a synthetic molecular sieve catalyst is arranged between the liquid level formed by the alpha-pinene and the cooling device, and the reaction duration is 0.5-2h to obtain camphene mother liquor;
step two: putting the obtained camphene mother liquor into a first distillation tower, and distilling and separating tricyclene in the camphene mother liquor at the tower top of the first distillation tower;
step three: and (4) putting the camphene mother liquor treated in the step (II) into a second distillation tower, and distilling and separating camphene at the tower top of the second distillation tower to obtain high-purity camphene.
Further, the catalyst is one or more of mordenite, a sodium titanium metatitanate catalyst and aluminum chloride.
Further, the synthetic molecular sieve catalyst is one or more of HZSM-5, HZSM-22, ZSM-35, HMCM-49, MCM-22, MCM-56, MCM-36, MCM-41, MCM-48, mordenite, H beta zeolite, HY zeolite, SAPO-34 or SAPO-11.
Further, in the first step, the heating temperature of the alpha-pinene is 120-160 ℃.
Further, in the first step, the pressure in the reactive distillation column is normal pressure.
Further, in the first step, stirring is continuously carried out during the reaction process of the alpha-pinene, and the stirring speed is 140-.
The invention puts the catalyst into the distillation tower for catalyzing and dissimilating with a liquid layer formed by alpha-pinene, so as to obtain camphene, and in the process of catalytic isomerization, a part of liquid alpha-pinene is changed into alpha-pinene steam to rise due to heating and evaporation, which is taken as an improvement point of the invention, the top of the liquid layer formed by the alpha-pinene is also provided with a synthetic molecular sieve catalyst, the rising alpha-pinene steam needs to pass through the synthetic molecular sieve catalyst, the catalyst is subjected to catalytic dissimilation with the synthesized molecular sieve catalyst in the process of synthesizing the molecular sieve catalyst, compared with the traditional method of only adding a catalyst in the tower kettle, the preparation method provided by the invention can effectively improve the efficiency and the conversion rate of the catalytic isomerization of the alpha-pinene to form camphene.
In order to further improve the camphene content in the final product, the preparation method adopts a secondary distillation mode, firstly the tricyclene with lower boiling point in the camphene mother liquor is distilled out through the first distillation tower, then the camphene in the camphene mother liquor is distilled out through the second distillation tower, and the dipentene and the heavy oil with higher boiling point are left in the tower kettle.
Detailed Description
The invention discloses a preparation method for preparing camphene by alpha-pinene isomerization, which not only can obtain high-concentration camphene, but also effectively improves the speed of alpha-pinene isomerization and improves the production efficiency.
The technical solutions of the present invention will be described clearly and completely below, and it is obvious that the description is only a part of the embodiments of the present invention, not all embodiments. 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 discloses a preparation method for preparing camphene by alpha-pinene isomerism, which comprises the following operation steps:
the method comprises the following steps: placing a reaction raw material containing alpha-pinene in a reaction distillation tower, wherein a catalyst is put into the distillation tower, the catalyst is immersed below the liquid level formed by the alpha-pinene, heating a tower kettle of the reaction distillation tower, the alpha-pinene is catalyzed and isomerized to form camphene under the action of the catalyst, part of the alpha-pinene is evaporated and ascended, a cooling device is arranged at the top of the reaction distillation tower, the evaporated alpha-pinene is condensed and refluxed, a synthetic molecular sieve catalyst is arranged between the liquid level formed by the alpha-pinene and the cooling device, and the reaction duration is 0.5-2h to obtain camphene mother liquor;
step two: putting the obtained camphene mother liquor into a first distillation tower, and distilling and separating tricyclene in the camphene mother liquor at the tower top of the first distillation tower;
step three: and (4) putting the camphene mother liquor treated in the step (II) into a second distillation tower, and distilling and separating camphene at the tower top of the second distillation tower to obtain high-purity camphene.
The catalyst provided by the invention is one or more of mordenite, a sodium titanium metatitanate catalyst and aluminum chloride.
The synthetic molecular sieve catalyst provided by the invention is one or more of HZSM-5, HZSM-22, ZSM-35, HMCM-49, MCM-22, MCM-56, MCM-36, MCM-41, MCM-48, mordenite, H beta zeolite, HY zeolite, SAPO-34 or SAPO-11.
In the first step, the heating temperature of the alpha-pinene is 120-160 ℃.
In the first step, the pressure in the reactive distillation tower is normal pressure.
In the first step, stirring is continuously carried out in the reaction process of the alpha-pinene, and the stirring speed is 140-.
The invention puts the catalyst into the distillation tower for catalyzing and dissimilating with a liquid layer formed by alpha-pinene, so as to obtain camphene, and in the process of catalytic isomerization, a part of liquid alpha-pinene is changed into alpha-pinene steam to rise due to heating and evaporation, which is taken as an improvement point of the invention, the top of the liquid layer formed by the alpha-pinene is also provided with a synthetic molecular sieve catalyst, the rising alpha-pinene steam needs to pass through the synthetic molecular sieve catalyst, the catalyst is subjected to catalytic dissimilation with the synthesized molecular sieve catalyst in the process of synthesizing the molecular sieve catalyst, compared with the traditional method of only adding a catalyst in the tower kettle, the preparation method provided by the invention can effectively improve the efficiency and the conversion rate of the catalytic isomerization of the alpha-pinene to form camphene.
In order to further improve the camphene content in the final product, the preparation method adopts a secondary distillation mode, firstly the tricyclene with lower boiling point in the camphene mother liquor is distilled out through the first distillation tower, then the camphene in the camphene mother liquor is distilled out through the second distillation tower, and the dipentene and the heavy oil with higher boiling point are left in the tower kettle.
Hereinafter, the following examples are given, and the raw materials used in the examples are all commercially available or self-made, and unless otherwise specified, the units are (kg).
Example 1:
the embodiment discloses a preparation method for preparing camphene by alpha-pinene isomerization, which comprises the following operation steps:
the method comprises the following steps: placing a reaction raw material containing alpha-pinene in a reactive distillation tower, and determining that the reaction raw material comprises: 10% of tricyclene, 75% of camphene, and 15% of other limonene, terpinolene, fusel, longifolene, etc., wherein mordenite is put into the distillation tower, the mordenite is immersed below the liquid level formed by the alpha-pinene, the tower kettle of the reaction distillation tower is heated, the reaction condition is that under normal pressure, the heating temperature of the alpha-pinene is 120-160 ℃, the alpha-pinene is continuously stirred in the reaction process of the alpha-pinene, the stirring speed is 160 r/min, the alpha-pinene is catalyzed and isomerized to camphene under the action of a catalyst, part of the alpha-pinene is evaporated and ascended, a cooling device is arranged at the top of the reaction distillation tower, the evaporated alpha-pinene is condensed and refluxed, and a synthetic molecular sieve catalyst is arranged between the liquid level formed by the alpha-pinene and the cooling device, the synthesized molecular sieve is HZSM-5, and the reaction duration is 1h to obtain camphene mother liquor;
step two: putting the obtained camphene mother liquor into a first distillation tower, and distilling and separating tricyclene in the camphene mother liquor at the tower top of the first distillation tower;
step three: and (3) putting the camphene mother liquor treated in the step (II) into a second distillation tower, distilling and separating camphene at the tower top of the second distillation tower, and marking the obtained camphene as a sample S1.
Example 2:
the embodiment discloses a preparation method for preparing camphene by alpha-pinene isomerization, which comprises the following operation steps:
the method comprises the following steps: placing a reaction raw material containing alpha-pinene in a reactive distillation tower, and determining that the reaction raw material comprises: 7% of tricyclene, 73% of camphene, and 20% of other limonene, terpinolene, fusel, longifolene and the like, wherein mordenite is put into the distillation tower, the mordenite is immersed below the liquid level formed by the alpha-pinene, the tower kettle of the reaction distillation tower is heated, the reaction condition is that under normal pressure, the heating temperature of the alpha-pinene is 120-160 ℃, the alpha-pinene is continuously stirred in the reaction process of the alpha-pinene, the stirring speed is 160 r/min, the alpha-pinene is catalyzed and isomerized to form camphene under the action of a catalyst, part of the alpha-pinene is evaporated and ascended, a cooling device is arranged at the top of the reaction distillation tower, the evaporated alpha-pinene is condensed and refluxed, and a synthetic molecular sieve catalyst is arranged between the liquid level formed by the alpha-pinene and the cooling device, the synthesized molecular sieve is HZSM-5, and the reaction duration is 1h to obtain camphene mother liquor;
step two: putting the obtained camphene mother liquor into a first distillation tower, and distilling and separating tricyclene in the camphene mother liquor at the tower top of the first distillation tower;
step three: and (3) putting the camphene mother liquor treated in the step (II) into a second distillation tower, distilling and separating camphene at the tower top of the second distillation tower, and marking the obtained camphene as a sample S2.
Example 3:
the embodiment discloses a preparation method for preparing camphene by alpha-pinene isomerization, which comprises the following operation steps:
the method comprises the following steps: placing a reaction raw material containing alpha-pinene in a reactive distillation tower, and determining that the reaction raw material comprises: 9% of tricyclene, 70% of camphene, and 21% of other limonene, terpinolene, fusel, longifolene and the like, wherein mordenite is put into the distillation tower, the mordenite is immersed below the liquid level formed by the alpha-pinene, the tower kettle of the reaction distillation tower is heated, the reaction condition is that under normal pressure, the heating temperature of the alpha-pinene is 120-160 ℃, the alpha-pinene is continuously stirred in the reaction process of the alpha-pinene, the stirring speed is 160 r/min, the alpha-pinene is catalyzed and isomerized to form camphene under the action of a catalyst, part of the alpha-pinene is evaporated and ascended, a cooling device is arranged at the top of the reaction distillation tower, the evaporated alpha-pinene is condensed and refluxed, and a synthetic molecular sieve catalyst is arranged between the liquid level formed by the alpha-pinene and the cooling device, the synthesized molecular sieve is HZSM-5, and the reaction duration is 1h to obtain camphene mother liquor;
step two: putting the obtained camphene mother liquor into a first distillation tower, and distilling and separating tricyclene in the camphene mother liquor at the tower top of the first distillation tower;
step three: and (3) putting the camphene mother liquor treated in the step (II) into a second distillation tower, distilling and separating camphene at the tower top of the second distillation tower, and marking the obtained camphene as a sample S3.
Comparative example 1
The comparative example discloses a preparation method for preparing camphene by alpha-pinene isomerism, which comprises the following operation steps:
the method comprises the following steps: placing a reaction raw material containing alpha-pinene in a reactive distillation tower, and determining that the reaction raw material comprises: 10% of tricyclene, 75% of camphene, 75% of other limonene, terpinolene, fusel, longifolene and the like, wherein the content of mordenite is 15%, the mordenite is put into the distillation tower, the mordenite is immersed below the liquid level formed by the alpha-pinene, the tower kettle of the reaction distillation tower is heated, the reaction condition is that under normal pressure, the heating temperature of the alpha-pinene is 120-160 ℃, the alpha-pinene is continuously stirred in the reaction process of the alpha-pinene, the stirring speed is 160 r/min, the alpha-pinene is catalyzed and isomerized to camphene under the action of a catalyst, part of the alpha-pinene is evaporated and ascended, a cooling device is arranged at the top of the reaction distillation tower, the evaporated alpha-pinene is condensed and refluxed, and the reaction duration is 1h, so that a camphene mother solution is obtained;
step two: in the rectifying tower, the obtained camphene mother liquor is marked as a sample D1 in the rectifying tower.
Sample detection
The product samples S1, S2, S3 obtained in examples 1 to 3 and the product sample D1 obtained in comparative example 1 were subjected to content measurement.
The detection result shows that the content of camphene in the sample S1 is 98.7%, the content of camphene in the sample S2 is 99.1%, the content of camphene in the sample S2 is 98.3%, and the content of camphene in the sample D1 is 96.4%.
In conclusion, the preparation method for preparing camphene by alpha-pinene isomerism provided by the invention effectively improves the camphene content in the product and is beneficial to producing high-purity camphene.
The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.

Claims (6)

1. A preparation method for preparing camphene by alpha-pinene isomerization is characterized by comprising the following operation steps:
the method comprises the following steps: placing a reaction raw material containing alpha-pinene in a reaction distillation tower, wherein a catalyst is put into the distillation tower, the catalyst is immersed below the liquid level formed by the alpha-pinene, heating a tower kettle of the reaction distillation tower, the alpha-pinene is catalyzed and isomerized to form camphene under the action of the catalyst, part of the alpha-pinene is evaporated and ascended, a cooling device is arranged at the top of the reaction distillation tower, the evaporated alpha-pinene is condensed and refluxed, a synthetic molecular sieve catalyst is arranged between the liquid level formed by the alpha-pinene and the cooling device, and the reaction duration is 0.5-2h to obtain camphene mother liquor;
step two: putting the obtained camphene mother liquor into a first distillation tower, and distilling and separating tricyclene in the camphene mother liquor at the tower top of the first distillation tower;
step three: and (4) putting the camphene mother liquor treated in the step (II) into a second distillation tower, and distilling and separating camphene at the tower top of the second distillation tower to obtain high-purity camphene.
2. The method of claim 1 wherein the catalyst is one or more of mordenite, sodium titanium metatitanate catalyst, and aluminum chloride.
3. The method of claim 1, wherein the synthesized molecular sieve catalyst is one or more of HZSM-5, HZSM-22, ZSM-35, HMCM-49, MCM-22, MCM-56, MCM-36, MCM-41, MCM-48, mordenite, H beta zeolite, HY zeolite, SAPO-34 or SAPO-11.
4. The method of claim 1 wherein the first step of heating the alpha-pinene to a temperature of 120-160 ℃.
5. The method of claim 4 wherein in step one, the pressure in the reactive distillation column is atmospheric pressure.
6. The method as claimed in claim 1, wherein the first step of stirring is performed continuously during the reaction of α -pinene at a stirring speed of 140-.
CN201710398997.4A 2017-05-31 2017-05-31 Preparation method for preparing camphene by alpha-pinene isomerization Active CN107892640B (en)

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CN109721468A (en) * 2018-12-21 2019-05-07 怀集县长林化工有限责任公司 A kind of australene bisabolene isomer prepares the preparation method of terpineol
CN109721451A (en) * 2018-12-21 2019-05-07 怀集县长林化工有限责任公司 A kind of australene bisabolene isomer prepares the preparation method of limonene
CN114702387B (en) * 2022-04-18 2024-02-27 江西美龙达新材料有限公司 Isobornyl (meth) acrylate and preparation method thereof

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GB190716532A (en) * 1907-07-18 1907-12-31 Otto Zeitschel Improved Process for the Manufacture of Acid Esters of Cyclical Terpene Alcohols.
CN102126904A (en) * 2011-01-20 2011-07-20 大连理工大学 Method for isomerizing alpha-pinene
CN103285613A (en) * 2013-05-08 2013-09-11 厦门大学 Infinite reflux reaction distillation device of synthesizing terpineol and synthesizing method of device
CN104370740A (en) * 2014-10-20 2015-02-25 上海华谊(集团)公司 Production method of isobornyl acetate

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB190716532A (en) * 1907-07-18 1907-12-31 Otto Zeitschel Improved Process for the Manufacture of Acid Esters of Cyclical Terpene Alcohols.
CN102126904A (en) * 2011-01-20 2011-07-20 大连理工大学 Method for isomerizing alpha-pinene
CN103285613A (en) * 2013-05-08 2013-09-11 厦门大学 Infinite reflux reaction distillation device of synthesizing terpineol and synthesizing method of device
CN104370740A (en) * 2014-10-20 2015-02-25 上海华谊(集团)公司 Production method of isobornyl acetate

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