CN105693471B - The preparation method of thymol - Google Patents
The preparation method of thymol Download PDFInfo
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- CN105693471B CN105693471B CN201610040090.6A CN201610040090A CN105693471B CN 105693471 B CN105693471 B CN 105693471B CN 201610040090 A CN201610040090 A CN 201610040090A CN 105693471 B CN105693471 B CN 105693471B
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- Y02P20/584—Recycling of catalysts
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Abstract
The present invention provides a kind of preparation methods of thymol, it includes the following steps: after mixing eucalyptus citriodora oil with silica gel, carrying out cyclization to refraction coefficient of the sampling Detection sample at 20 DEG C is 1.4720~1.4723 and fragrance of the sample with isopulegol, discharging, obtains isopulegol；After the isopulegol is gasified, dehydrogenation reaction is carried out by copper-nickel catalyst at 200~300 DEG C, obtains the liquid thymol that the refraction coefficient at 20 DEG C is 1.4850~1.5100.Compared with prior art, the present invention is with following the utility model has the advantages that overcoming the high-temperature and high-pressure conditions of tradition pair gram alkylated reaction harshness as made from this method, reaction temperature is moderate, recyclable catalyst is used, thymol purity is high that is environmental-friendly, being prepared, keeps color stability within storage period, smell is constant, and content is slightly decreased.
Description
Technical field
The present invention relates to a kind of preparation methods of thymol, belong to technical field of medicine synthesis.
Background technique
Thymol, also known as thymol (1963 editions Chinese Pharmacopoeias), thymol, Thymol, the entitled 2- isopropyl of chemistry
Base -5- methylphenol, the bactericidal effect of thymol is stronger than phenol, and toxicity is low, has sterilization, antifungal to oral cavity mucosa
Effect, has anti-corrosion, local anesthetic action to saprodontia chamber, for oral cavity, the disinfection and sterilization of throat, dermatophytosis, actinomycosis and ear
It is scorching.It can promote tra cheo-oesophageal voice, be conducive to the secretion of tracheal mucus, easily play phlegm-dispelling functions, then added with bactericidal effect, thus it is available
In treatment tracheitis, pertussis etc..There are very strong acaricidal action, the 1% solution half an hour death rate 100%, 0.03% solution
100% is killed for 24 hours.Also it can be used as ascarifuge agent.0.05~0.2% solution of thymol have it is stronger kill protoscolex effect, can
Achieve the effect that 100% kill protoscolex in 5~10min, acts on reliable, small toxicity rapidly.
Currently, the natural origin of thymol is in Lamiaceae plant thyme Thymus serpyllum L. grass, thyme
T.vulgaris L. herb, wild marjoram Origanum vulgare L. herb, Dracocephalum moldavica Dracocephalum moldavicum
L. herb, thick fruit celery Trachyspermum ammi (L.) the Sprague seed of umbelliferae.The thyme being extracted from plants
Phenol yield is low, at high cost, and environmental pressure is big, therefore musk ambrette grass phenol has certain technical advantage, and there are wide market skies
Between.
At abroad, synthetic method is mainly the preparation of fourier alkylated reaction, using metacresol and chloropropane, propylene or isopropyl
The substance containing isopropyl such as alcohol is raw material, is carried out under high pressure, isomers easy to produce and more induced by alkyl hydroxybenzene etc., the later period point
From complexity, higher cost.
To solve these problems, application No. is a kind of thymol is referred in 200810219106.5 Chinese patent
Preparation method.The method is raw material using metacresol and isopropanol, is reacted in fixed bed reactors, with γ-Al2O3As
Catalyst prepares thymol at 200~350 DEG C of reaction temperature.The raw material sources of the technique are abundant extensively, but yield is lower
40%, and later-period purification process is indefinite, and impurity is in confused situation.
Chinese patent 104177233A, i.e. " a kind of synthetic method of thymol " disclose one kind with menthol as original
Material obtains menthol gas through gasification, under the conveying of carrier gas, with activated carbon supported Ni/Na2SiO3Dehydrogenation occurs for catalyst
Reaction, is condensed, purifies the method for obtaining thymol.Catalyst used in this method is expensive, at later-period purification
Manage complex procedures.
Summary of the invention
The purpose of invention is, provides a kind of method of continuous catalysis musk ambrette grass phenol, provides a kind of reproducible urge
Agent, compared to existing patented technology, this law technique exploitativeness is strong, while also accordingly overcoming prior art method in technique
And the defect of environmental protection aspect.
The present invention is achieved by the following technical solutions: preparing reproducible catalyst by sedimentation first, then
Thymol is prepared by rectifying plus two step of dehydrogenation reaction.This law makes it voluntarily by heating reaction substrate essence isopulegol
Into in reactor, catalysis occurs with copper-nickel catalyst and reacts, continuous feed, by the way that reaction product decrease temperature crystalline, centrifugation is dry
It is dry to be prepared into thymol.Reaction substrate essence isopulegol charging rate is 1~10kg/min, and temperature of reactor control exists
200~300 DEG C.
The present invention provides a kind of preparation methods of thymol, include the following steps:
After eucalyptus citriodora oil is mixed with silica gel, carrying out cyclization to refraction coefficient of the sampling Detection sample at 20 DEG C is
1.4720~1.4723 and the sample have isopulegol fragrance, discharging, obtain isopulegol；
After the isopulegol is gasified, dehydrogenation reaction is carried out by copper-nickel catalyst at 200~300 DEG C,
Obtain the liquid thymol that the refraction coefficient at 20 DEG C is 1.4850~1.5100.
Silica gel belongs to acidic catalyst, can choose other acidic catalysts, but later separation is complicated, needs soda acid tune
Section.Silica gel dosage is insufficient, and the reaction time extends, and the by-product that aldol reaction occurs will be caused to increase under reaction temperature, made
It is reduced at later step yield.
In copper-nickel catalyst, activity unit is copper and nickel element, and the dehydration that alkaline components can reduce dehydrogenation reaction is anti-
It answers, avoids catalyst toxicity poisoning, and then avoid the reduction of catalytic activity.
Preferably, the preparation method of the copper-nickel catalyst includes the following steps:
Copper sulphate and nickel sulfate are added in first part of purified water, stirring and dissolving is complete, obtains copper sulphate and nickel sulfate is mixed
Heshui solution；
Diatomite is added at 30~60 DEG C in second part of purified water, sodium carbonate is added after stirring, to the sodium carbonate
The copper sulphate and nickel sulfate mixed aqueous solution all is added after dissolution, is reacted；30~60 DEG C are selected, catalyst will be promoted
Inorganic reaction process, neutral temperature drops the diffusion of stimulating activity elemental copper and nickel, is conducive to it on diatomite particle
Deposition.
Reaction route are as follows:
In the reaction product be added water after, add include potassium carbonate and magnesia pasty liquid, after stirring, drying,
Obtain the copper-nickel catalyst.
Preferably, the temperature of the cyclization is 140~200 DEG C.
Preferably, the weight ratio of the eucalyptus citriodora oil and silica gel is (30~100): (0.5~3).
Preferably, further include the steps that purifying thymol: being specially coarse crystallization, recrystallization and baking
It is dry.
Preferably, the weight ratio of the copper sulphate, nickel sulfate and first part of purified water is 1:(1~2): (1~
3)。
Preferably, the weight ratio of the diatomite, sodium carbonate and second part of purified water is (0.5~2): (1~
2.5): (16~23).If the ratio is excessively high, alkaline components are very few, and the sulfate ion that copper and nickel element combine can not be set
It changes, if the ratio is too low, alkaline components are excessive, and will cause catalyst is that target product is dehydrated, and under high temperature, dehydration makes
Catalyst inactivation.
Preferably, it is described include potassium carbonate and magnesia pasty liquid in, the weight of potassium carbonate and magnesia
Than for (0.01~5): (0.01~1.00).
Preferably, further include the steps that purifying isopulegol: specially be fractionated.
More specifically, the operation of each step is as follows:
Step 1: by eucalyptus citriodora oil and the silica gel being crushed between 60~90 mesh, (dosage of silica gel is eucalyptus citriodora oil weight
2~3% or so) mixing, react 7~9 hours between 150~170 DEG C, up to sampling Detection to reaction solution sample at 20 DEG C
Refraction coefficient be 1.4720~1.4723 and sample have isopulegol fragrance, discharging；The above-mentioned product of rectifying, before removal
Fraction and tails obtain smart isopulegol；
Silica gel is crushed to certain fineness, is conducive to the dehydration condensation of target component in eucalyptus citriodora oil.
Step 2: by smart isopulegol obtained by step 1 by heating and gasifying, gas passes through at 200~300 DEG C is urged
Agent carries out dehydrogenation reaction, detects product index of refraction, collects the product that the refraction coefficient at 20 DEG C is 1.4850~1.5100,
By decrease temperature crystalline, centrifugal drying is prepared into thymol.
Compared with prior art, the present invention have it is following the utility model has the advantages that
1, the thymol stability as made from this method is good, and purity is high keeps color stability, smell within storage period
Constant, content is unaffected；
2, the method for the present invention is easy, is suitable for industrial-scale production；
3, the renewable use of catalyst that this method uses, long service life；
4, the device that this method uses is original creation design, continuous feed, sustained response；
Thymol consersion unit consists of two parts, respectively reaction tube and economizer bank, and economizer bank is added by tube bottom
Isopulegol raw material, passes through heating and gasifying；Reaction tube is made of two pipe of size, the cavity filling cupro-nickel catalysis between two pipes
Agent, gasified raw material are entered in cavity by piping connection, are controlled in cavity by temperature and are guaranteed that catalysis reaction carries out, reaction tube bottom
Portion connects thymol product；
5, the processing of this method later-period purification is simple, decrease temperature crystalline；
6, the eucalyptus citriodora oil that the method uses extracts from south China or even Southeast Asia all over raw lemon scented gum, and raw material is easy to obtain,
It is low in cost.
Specific embodiment
The present invention is described in detail combined with specific embodiments below.Following embodiment will be helpful to the technology of this field
Personnel further understand the present invention, but the invention is not limited in any way.It should be pointed out that the ordinary skill of this field
For personnel, without departing from the inventive concept of the premise, various modifications and improvements can be made.These belong to the present invention
Protection scope.
Embodiment 1
The present embodiment is related to a kind of preparation of thymol, specifically comprises the following steps:
One, the preparation of catalyst
(1) weigh copper sulphate and nickel sulfate, add purified water, copper sulphate: nickel sulfate: water weight ratio is 1:(1~2): (4~
6), stirring and dissolving is complete；
(2) 16~23 parts of purified waters are measured to pour into a mixing bowl, is heated；It is added with stirring 0.5~2 part of diatomite；Stirring
Under be gradually added 1~2.5 part of sodium carbonate again, to its all dissolve；Continue to add copper sulphate under stirring and nickel sulfate mixing is water-soluble
Liquid completes reaction.
(3) a collection of moist catalysis prepared by (1)-(2) is incorporated to together, about 1L water is added to stir into paste, then plus by
0.1~0.7 part of potassium carbonate wiring solution-forming and the pasty liquid being made by 0.01~1.00 part of magnesia, are sufficiently stirred 7~10 hours,
Product is placed in baking oven drying.
Two, thymol (thymol can be obtained by GC-MS test) preparation process
(1) be cyclized: 600~1000Kg eucalyptus citriodora oil is added in reaction pot after mixing with 10~45Kg of silica gel and is stirred
It mixes.Heating reaction, withdrawing fluid discharge are opened, reheating allows temperature to continue to rise to 140~200 DEG C of reaction temperature, reaction 8~
After 14 hours, sampling survey refraction index (20 DEG C), (20 DEG C) stabilization of refraction index 1.4710~1.4730 and have slightly different Hu
When the peculiar fragrance of menthol, cooling down.Stop stirring to kettle temperature decline, supernatant is collected after feed clarification and is fractionated.
(2) it is fractionated: the feed liquid clarified is put into fractionation pot.It opens condenser and cooler inlet valve and opens heating
Coiled pipe exhaust valve closes exhaust valve, then proceedes to start to steam after vacuum pump infinite reflux one hour after condensed water in vomit pipe
Smart isopulegol.
Process conditions and parameter: control reflux ratio are as follows: 26:4~20:10；Product index of refraction is 1.4715~1.4730.
(3) dehydrogenation: after the completion of a, catalyst oxidation, to already oxidised copper-nickel catalyst, at 200~450 DEG C, hydrogenation
It is converted into going back native copper, reduced nickel.
B, smart isopulegol charging is completed, and also by economizer bank constant temperature in 230~280 DEG C when reaction tube constant temperature, is opened
Inlet valve, by defined charging quantity toward feeding in reaction tube.The thymol oozed is collected after charging, surveys refraction index (20
℃).General refraction index (20 DEG C) maintains between 1.4850~1.5100.
(4) it purifies
Thymol crude product is obtained through coarse crystallization, recrystallization, drying, this passes through detection condensation point, liquid Moschus in the process
Careless phenol reaches 1.4850 or more by testing its refraction coefficient, and primary crystal condensation point is 46~48 DEG C, and condensation point is 48.5 after recrystallization
DEG C or more, condensation point is 49 DEG C or more after drying, after obtaining thymol finished product, is packed.
Embodiment 2
The present embodiment is related to a kind of preparation of thymol, specifically comprises the following steps:
One, the preparation of catalyst
(1) weigh copper sulphate and nickel sulfate, add purified water, copper sulphate: nickel sulfate: water weight ratio is 1:1.5:5, is stirred molten
Solution is complete；
(2) 16~23 parts of purified waters are measured to pour into a mixing bowl, is heated；It is added with stirring 0.5~2 part of diatomite；Stirring
Under be gradually added 1~2.5 part of sodium carbonate again, to its all dissolve；Continue to add copper sulphate under stirring and nickel sulfate mixing is water-soluble
Liquid completes reaction.
(3) a collection of moist catalysis prepared by (1)-(2) is incorporated to together, about 1L water is added to stir into paste, then plus by
0.1~0.7 part of potassium carbonate wiring solution-forming and the pasty liquid being made by 0.01~1.00 part of magnesia, are sufficiently stirred 7~10 hours,
Product is placed in baking oven drying.
Two, thymol preparation process
(1) be cyclized: 600~1000Kg eucalyptus citriodora oil is added in reaction pot after mixing with 10~45Kg of silica gel and is stirred
It mixes.Heating reaction, withdrawing fluid discharge are opened, reheating allows temperature to continue to rise to 140~200 DEG C of reaction temperature, reaction 8~
After 14 hours, sampling survey refraction index (20 DEG C), (20 DEG C) stabilization of refraction index 1.4710~1.4730 and have slightly different Hu
When the peculiar fragrance of menthol, cooling down.Stop stirring to kettle temperature decline, supernatant is collected after feed clarification and is fractionated.
(2) it is fractionated: the feed liquid clarified is put into fractionation pot.It opens condenser and cooler inlet valve and opens heating
Coiled pipe exhaust valve closes exhaust valve, then proceedes to start to steam after vacuum pump infinite reflux one hour after condensed water in vomit pipe
Smart isopulegol.
Process conditions and parameter: the reflux ratio for controlling distillation operation steams product: return product is 20:10 (reflux ratio)
1.4715-1.4730。
(3) dehydrogenation: after the completion of a, catalyst oxidation, to already oxidised copper-nickel catalyst, at 200~450 DEG C, hydrogenation
It is converted into going back native copper, reduced nickel.
B, smart isopulegol charging is completed, and also by economizer bank constant temperature in 230~280 DEG C when reaction tube constant temperature, is opened
Inlet valve, by defined charging quantity toward feeding in reaction tube.The thymol oozed is collected after charging, surveys refraction index (20
℃).General refraction index (20 DEG C) maintains between 1.4850~1.5100.
(4) it purifies
Thymol crude product is obtained to be packed after obtaining thymol finished product through coarse crystallization, recrystallization, drying.
In conclusion the present invention have it is following the utility model has the advantages that
1, the thymol stability as made from this method is good, and purity is high keeps color stability, smell within storage period
Constant, content is unaffected；
2, the method for the present invention is easy, is suitable for industrial-scale production；
3, the renewable use of catalyst that this method uses, long service life；
4, the device that this method uses is original creation design, continuous feed, sustained response；
Thymol consersion unit consists of two parts, respectively reaction tube and economizer bank, and economizer bank is added by tube bottom
Isopulegol raw material, passes through heating and gasifying；Reaction tube is made of two pipe of size, the cavity filling cupro-nickel catalysis between two pipes
Agent, gasified raw material are entered in cavity by piping connection, are controlled in cavity by temperature and are guaranteed that catalysis reaction carries out, reaction tube bottom
Portion connects thymol product；
5, the processing of this method later-period purification is simple, decrease temperature crystalline；
6, the eucalyptus citriodora oil that the method uses extracts from south China or even Southeast Asia all over raw lemon scented gum, and raw material is easy to obtain,
It is low in cost.
Specific embodiments of the present invention are described above.It is to be appreciated that the invention is not limited to above-mentioned
Particular implementation, those skilled in the art can make various deformations or amendments within the scope of the claims, this not shadow
Ring substantive content of the invention.
Claims (1)
1. a kind of preparation method of thymol, which comprises the steps of:
After eucalyptus citriodora oil is mixed with silica gel, carrying out cyclization to refraction coefficient of the sampling Detection sample at 20 DEG C is
1.4720~1.4723 and the sample have isopulegol fragrance, discharging, obtain isopulegol；
After the isopulegol is gasified, dehydrogenation reaction is carried out by copper-nickel catalyst at 200~300 DEG C, is obtained
The liquid thymol that refraction coefficient at 20 DEG C is 1.4850~1.5100；
The Preparation equipment of the thymol consists of two parts, respectively reaction tube and economizer bank, and the economizer bank passes through pipe
Isopulegol raw material is added in bottom, passes through heating and gasifying；The reaction tube is made of two pipe of size, the cavity filling between two pipes
Copper-nickel catalyst, gasified raw material are entered in cavity by piping connection, are controlled in cavity by temperature and are guaranteed that catalysis reaction carries out,
Reaction bottom of the tube connects thymol product；
The preparation method of the copper-nickel catalyst includes the following steps:
Copper sulphate and nickel sulfate are added in first part of purified water, stirring and dissolving is complete, obtains copper sulphate and nickel sulfate mixing water
Solution；
Diatomite is added at 30~60 DEG C in second part of purified water, sodium carbonate is added after stirring, it is whole to the sodium carbonate
The copper sulphate and nickel sulfate mixed aqueous solution are added after dissolution, is reacted；
In the reaction product be added water after, add include potassium carbonate and magnesia pasty liquid, after stirring, drying, obtain
The copper-nickel catalyst；
The temperature of the cyclization is 140~200 DEG C；
The weight ratio of the eucalyptus citriodora oil and silica gel is (30~100): (0.5~3)；
Further include the steps that purifying thymol: being specially coarse crystallization, recrystallization and drying；
The weight ratio of the copper sulphate, nickel sulfate and first part of purified water is 1:(1~2): (1~3)；
The weight ratio of the diatomite, sodium carbonate and second part of purified water is (0.5~2): (1~2.5): (16~23)；
It is described include potassium carbonate and magnesia pasty liquid in, the weight ratio of potassium carbonate and magnesia is (0.01~5):
(0.01~1.00)；
Further include the steps that purifying isopulegol: specially be fractionated.
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104177233A (en) * | 2014-09-10 | 2014-12-03 | 湖南湘易康制药有限公司 | Thymol synthesis method |
| CN104744219A (en) * | 2015-04-22 | 2015-07-01 | 江苏理工学院 | Preparation method of thymol |
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2016
- 2016-01-21 CN CN201610040090.6A patent/CN105693471B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104177233A (en) * | 2014-09-10 | 2014-12-03 | 湖南湘易康制药有限公司 | Thymol synthesis method |
| CN104744219A (en) * | 2015-04-22 | 2015-07-01 | 江苏理工学院 | Preparation method of thymol |
Non-Patent Citations (2)
| Title |
|---|
| 柠檬桉叶油合成麝香草酚的研究;陈保乃;《生物质化学工程》;19811231(第8期);第5-7页 |
| 麝香草酚的合成;杨泽榆等;《催化学报》;19900131;第11卷(第1期);第80-82页 |
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