Device and method for extracting star anise essential oil

Abstract

The invention discloses an extraction device and an extraction method of star anise essential oil, and belongs to the technical field of vegetable oil extraction. The extraction device provided by the invention comprises a round-bottom flask, an air condensation pipe, a distillation head, a condensation pipe, a receiving pipe and a receiving bottle, the opening of the round-bottom flask is connected with the bottom of the air condensation pipe; the top of the air condensation pipe is connected with a bottom end pipe of the distillation head; a side end pipe of the distillation head is connected with the top of the condensation pipe; the bottom of the condensation pipe is connected with the top of the receiving pipe; inserting the tail part of the receiving tube into a receiving bottle; and a polymeric membrane is loaded at the top of the air condensation pipe. According to the extraction device and the extraction method of the star anise essential oil, the problems of long time consumption, large steam consumption and high energy consumption in a traditional extraction process are solved, and meanwhile, the extraction rate of the star anise oil and the extraction rate of the effective component anethole are greatly improved.

Description

Technical Field

[0001] The present application belongs to the technical field of plant oil extraction, and in particular to an extraction device and an extraction method for star anise essential oil. Background Art

[0002] Star anise (Fructus Anisi Stellati), commonly known as star anise, five-spice star anise, aniseed, etc., is a plant of the genus Illicium in the family Schisandraceae. Star anise oil is a volatile aromatic substance extracted from star anise by steam distillation, extrusion, cold soaking or solvent extraction. The fruit is a famous seasoning spice with a sweet taste. It is also used for medicinal purposes, with the functions of dispelling wind and regulating qi, harmonizing the stomach and regulating the middle. It is used for nausea and vomiting, cold pain in the abdomen, and bloating in the stomach. However, eating too much can damage the eyes and cause sores. The peel, seeds, and leaves all contain aromatic oils. Star anise oil is an important raw material for the manufacture of cosmetics, medicines, sweet wine, beer, and the food industry.

[0003] The extraction methods of star anise oil include steam distillation, solvent extraction and supercritical fluid extraction. Among them, the solvent extraction method uses organic solvents such as ethanol or hexane to dissolve the oil components in the plant, but residual solvents may be introduced, affecting the purity and safety of the product. Supercritical fluid extraction technology can efficiently extract active ingredients in plants under low temperature conditions, reduce the degradation of heat-sensitive components, and does not produce harmful residues. It has gradually attracted attention in recent years. However, this method often requires very high pressure, which is a huge test for experimental equipment, with high cost and energy consumption, and it is difficult to achieve scale. Therefore, steam distillation has become the most commonly used extraction technology. This technology is to pass water vapor into organic matter that is insoluble or difficult to dissolve in water but has a certain volatility, so that the organic matter is distilled out with water vapor at a temperature below 100°C. It is often used in the following situations: distilling high-boiling point organic substances that will decompose at normal pressure; separating organic matter from a large amount of resinous impurities or non-volatile impurities; separating adsorbed liquids from reaction mixtures with more solids; extraction of natural products, such as essential oils, certain alkaloids, etc. Steam distillation technology can effectively retain the aromatic components and bioactive components of plants. It is not only efficient but also relatively environmentally friendly and suitable for large-scale production.

[0004] The traditional steam distillation method for extracting essential oils has the advantages of mild extraction conditions, high efficiency, removal of impurities, simple operation and wide application range, but it also has disadvantages such as low extraction efficiency, long time, low energy utilization, large amount of water resources and low utilization rate, high emulsification of the obtained distillate, loss of heat-sensitive components, and complex post-processing. Therefore, it is necessary to improve the utilization efficiency of water vapor and perform preliminary oil-water separation to achieve efficient extraction.

[0005] Traditional separation technology is difficult to achieve simple and efficient gas phase separation or is not easy to apply to teaching experiments due to its high cost. Fortunately, membrane separation technology can solve this problem well, and because of its high separation efficiency, high selectivity and environmental protection, membrane preparation technology and membrane-based separation processes have developed rapidly in my country in the past two decades. Common membrane material matrices include carbon, ceramics, polymers, gels, metal networks and biomass. Scientists have designed microstructures or modified the surface of membrane materials to enable them to be used in different production fields, such as filtration of particles in sewage and oil-water separation.

[0006] Therefore, how to use membrane separation technology to improve the experimental equipment of traditional steam distillation method for extracting star anise oil is of great significance for solving key problems such as low yield of star anise oil extraction, long experimental time and high energy consumption. Summary of the invention

[0007] In order to overcome the problems of long time consumption, large steam consumption, high energy consumption, etc. in the above-mentioned prior art, the present application provides an extraction device and an extraction method for star anise essential oil. The use of the device and method not only saves extraction time and improves the essential oil yield of star anise, but also improves the extraction rate of anethole, the main active ingredient of star anise essential oil.

[0008] In order to achieve the above-mentioned invention object, this application provides the following technical solutions:

[0009] On the one hand, the present application provides an extraction device for star anise essential oil, comprising a round-bottom flask (1), an air condenser (2), a distillation head (3), a condenser (4), a receiving tube (5), and a receiving bottle (6);

[0010] The mouth of the round-bottom flask (1) is connected to the bottom of the air condenser (2);

[0011] The top of the air condensation tube (2) is connected to the bottom tube of the distillation head (3);

[0012] The side end tube of the distillation head (3) is connected to the top of the condenser (4);

[0013] The bottom of the condenser tube (4) is connected to the top of the receiving tube (5);

[0014] Inserting the tail of the receiving tube (5) into the receiving bottle (6);

[0015] The top of the air condensation tube (2) is loaded with a polymer membrane (7).

[0016] Optionally, filter paper (8) is loaded at the bottom of the air condensation tube (2).

[0017] Optionally, a thermometer (9) is inserted into the top of the distillation head (3).

[0018] In a second aspect, the present application provides a method for extracting star anise essential oil, which is carried out using the above-mentioned extraction device and comprises the following steps:

[0019] (1) crushing star anise to obtain star anise powder;

[0020] (2) Add distilled water and zeolite into a round-bottom flask and install an air condenser at the mouth of the flask;

[0021] (3) Filling filter paper at the bottom of the air condenser, placing the star anise powder on the filter paper, and then loading the polymer film on the top of the air condenser;

[0022] (4) Install the distillation head, condenser, receiving tube, and receiving bottle in sequence, and insert a thermometer at the top of the distillation head;

[0023] (5) Condensed water is introduced into the condenser tube from the lower opening and flows out from the upper opening, and the round-bottom flask is heated to start distillation until the distillate is clear and transparent, the flow rate is reduced, and no oil droplets of organic matter are contained, reaching the end point of distillation. The heat source is turned off, and the condensed water is stopped after the device is cooled;

[0024] (6) After the distillate cools to room temperature, remove the receiving bottle, add salt, stir thoroughly, and let stand to obtain a mixed solution;

[0025] (7) Pour the mixed solution into a pear-shaped separatory funnel, add ethyl acetate for extraction, repeat the extraction operation 2 to 4 times, discard the water layer, combine the ester layers, dry and distill them in sequence, evaporate the ethyl acetate, collect the residue, and obtain star anise essential oil.

[0026] Optionally, in step (1), the particle size of the star anise powder is 100 to 150 μm;

[0027] The star anise powder is used in an amount of 10 to 30 g.

[0028] Optionally, in step (1), the particle size of the star anise powder is independently selected from any value of 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, or any range between the two values;

[0029] The amount of the star anise powder is independently selected from any value among 10g, 15g, 20g, 25g, 30g or any range value therebetween.

[0030] In the present application, the star anise is crushed to a particle size of 100 to 150 μm by spherical graphite crushing, which can promote the dissolution of the effective ingredients in the star anise without destroying the structure of the effective ingredients in the star anise, thereby increasing the extraction rate of anethole.

[0031] Optionally, in step (2), the volume of the distilled water added is 2 / 3 to 3 / 4 of the volume of the round-bottom flask;

[0032] The dosage of the zeolite is 2 to 4 grains.

[0033] Preferably, in step (2), the volume of distilled water added is 3 / 4 of the volume of the round-bottom flask;

[0034] The amount of the zeolite used is 3 grains.

[0035] In the present application, the steam transmission path is shortened, and the star anise holding device is changed from a three-necked flask to an air condenser directly connected to the steam generating device, thereby shortening the distance between the steam generating device and the material to be distilled to reduce the heat loss of the steam during the transmission process. In addition, if the steam condenses in the air condenser, partial reflux will be formed (about 2 to 3 drops of partial reflux liquid per second), and the condensed water in the air condenser will flow back to the flask for reheating and evaporation, thereby improving the utilization rate of the water vapor.

[0036] Optionally, in step (3), the pore size of the filter paper is smaller than the particle size of the star anise powder.

[0037] Optionally, the polymer film is a single-layer film.

[0038] In this application, it is found through experiments that two or more layers of membrane material will significantly reduce the flux of water vapor, making it difficult to drive the oil droplets to migrate to the cooling device, resulting in low distillation product collected in the receiving bottle. Therefore, this application selects a single-layer membrane.

[0039] Optionally, the polymer membrane is a polytetrafluoroethylene hydrophobic membrane.

[0040] Optionally, the pore size of the polytetrafluoroethylene hydrophobic membrane is 0.4-0.5 μm.

[0041] Optionally, the pore size of the polytetrafluoroethylene hydrophobic membrane is 0.45 μm.

[0042] In the present application, it is found through experiments that the smaller the pore size of the membrane, the smaller the size of the molecules or particles that can pass through, so larger molecules or particles cannot pass through, resulting in a decrease in the overall pass rate; and the small pore size will increase the flow resistance of the fluid in the membrane, thereby excessively weakening the apparent migration rate of the fluid, and it is difficult for water vapor to drive the oil phase through the membrane to continue to migrate, thereby reducing the collection amount; the concentration gradient formed on both sides of the membrane may cause concentration polarization, especially when the pore size of the membrane is small, the polarization phenomenon will be more obvious, thereby affecting the permeability of the membrane; in addition, small pore size membranes may have higher selectivity and can effectively block certain substances. Although this can improve the separation efficiency, it may also reduce the overall yield. The present application found that membranes with a pore size in the range of 0.4 to 0.5 μm are more effective, especially the use of a 0.45 μm polytetrafluoroethylene hydrophobic membrane is the best.

[0043] Optionally, in step (5), during the distillation process, the thermometer temperature is controlled at 94-96° C.;

[0044] When oily liquid flows into the receiving bottle, adjust the heating voltage to control the flow rate of the distillate to 3-5s / drop.

[0045] Preferably, in step (5), during the distillation process, the temperature of the thermometer is controlled to be 95° C.

[0046] When oily liquid flows into the receiving bottle, adjust the heating voltage to control the flow rate of the distillate to 4s / drop.

[0047] In the present application, since the polymer membrane prevents the discharge of steam, the flow rate of the distillate is controlled at 3 to 5 seconds per drop, preferably 4 seconds per drop.

[0048] Optionally, in step (6), the ratio of the salt to the distillate in the receiving bottle is 3-3.5 g:10 mL;

[0049] The standing time is 10 to 20 minutes.

[0050] Optionally, in step (6), the dosage ratio of the salt to the distillate in the receiving bottle is independently selected from any value among 3g:10mL, 3.1g:10mL, 3.2g:10mL, 3.3g:10mL, 3.4g:10mL, 3.5g:10mL, or any range between two values;

[0051] The standing time is independently selected from any value among 10 min, 15 min, 20 min or any range between the two.

[0052] Optionally, in step (7), the amount of ethyl acetate used is 20-40% of the volume of the mixed solution;

[0053] The extraction time is 10 to 20 minutes per time.

[0054] Optionally, in step (7), the amount of ethyl acetate is independently selected from any value of 20%, 30%, 40% of the volume of the mixed solution, or any range between the two;

[0055] The extraction time is independently selected from any value of 10 min / time, 15 min / time, 20 min / time or any range value therebetween.

[0056] Optionally, in step (7), the drying is performed using anhydrous sodium sulfate;

[0057] The amount of anhydrous sodium sulfate used is 15-20% of the mass of the combined ester layer.

[0058] Optionally, the amount of anhydrous sodium sulfate is independently selected from any value of 15%, 16%, 18%, 20% of the mass of the combined ester layer, or any range between the two.

[0059] Optionally, in step (7), the distillation temperature is 70°C to 90°C;

[0060] The distillation time is 1 to 2 hours.

[0061] Optionally, in step (7), the distillation temperature is independently selected from any value among 70°C, 80°C, 90°C, or any range between the two;

[0062] The distillation time is independently selected from any value among 1 h, 1.5 h, 2 h, or any range between the two.

[0063] Compared with the prior art, this application has the following beneficial effects:

[0064] (1) The extraction device of star anise essential oil provided by the present application utilizes the selective permeability of the hydrophobic membrane material to perform preliminary separation on the mixed steam to increase the mass fraction of the oil phase in the distillate. Since the mass transfer of water vapor is obstructed, the steam transmission path before the hydrophobic membrane is relatively closed for water vapor. According to the ideal gas state equation, with the continuous heating and boiling, the gas pressure in this section of the path will rise significantly and increase the boiling point of water, that is, increase the temperature of water vapor and even the entire system, which will undoubtedly increase the vapor pressure of the substance to be separated and make it easier to distill out. Due to its own pressure and mixing with oil and gas, water vapor also has a certain flux at the hydrophobic membrane. Although this makes it impossible for the present application to directly obtain a high-purity product, it can effectively drive the migration of oil and gas to the condenser. The reflux principle is used to recycle water vapor, and the condensation of water vapor in the system also helps to keep warm and maintain the stability of the vapor pressure of each component during the separation process.

[0065] (2) The extraction device of star anise essential oil provided by the present application reduces the complexity of the traditional device, and reduces the number of glass instruments required from 8 to 7; the device as a whole is more concise, and the number of iron stands required is reduced from 3 to 2, and the floor space is reduced; the steam transmission path is shortened, and the star anise holding device is changed from a three-necked flask to an air condenser directly connected to the steam generating device, shortening the distance between the steam generating device and the material to be distilled to reduce the heat loss of steam during the transmission process. In addition, if the steam condenses in the holding device, partial reflux will be formed (about 2 to 3 drops of partial reflux liquid per second), and the condensed water in the holding device will flow back to the flask for reheating and evaporation, thereby improving the utilization rate of water vapor; reducing the complexity and risk during operation, the traditional experiment needs to frequently open the water stop clamp, otherwise it is easy to cause a large amount of water to accumulate in the holding device, reducing the distillation effect, but opening the water stop clamp may cause burns. In the experiment of the present application, the glass conduit is omitted, and the partial reflux in the air condenser can also avoid liquid accumulation or uneven flow, thereby improving the overall separation performance and making the experiment simpler and safer.

[0066] (3) The extraction method of star anise essential oil provided by the present application, through the combination of crushing and membrane separation technology with steam distillation, not only saves extraction time, but also reduces energy consumption, conforms to the concept of green development, and at the same time improves the yield of star anise essential oil. The GC-MS analysis results show that the composition of the main active ingredients in star anise essential oil is basically unchanged, among which the content of the active ingredient anethole is as high as 84.12%. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0068] Figure 1 Schematic diagram of the extraction device of the present application (Note: 1 represents a round-bottom flask; 2 represents an air condenser; 3 represents a distillation head; 4 represents a condenser; 5 represents a receiving tube; 6 represents a receiving bottle; 7 represents a polymer membrane; 8 represents filter paper; 9 represents a thermometer);

[0069] Figure 2 Schematic diagram of a conventional extraction device of Comparative Example 1 (Note: A represents a material holding device; B represents a burette; C represents a glass conduit; D represents a distillation flask; E represents a distillation head; and F represents a condenser);

[0070] Figure 3 A photo of the extraction device for this application;

[0071] Figure 4 This is a photo of the traditional extraction device of Comparative Example 1. DETAILED DESCRIPTION

[0072] The present application is further described below in conjunction with specific embodiments. The following are only a few embodiments of the present application, and are not intended to limit the present application in any form. Although the present application discloses the following preferred embodiments, they are not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the above disclosed technical content to make some changes or modifications are equivalent to equivalent implementation cases and are within the scope of the technical solution.

[0073] Unless otherwise specified, the raw materials in the examples of the present application were purchased from commercial sources and used directly without any special treatment.

[0074] Unless otherwise specified, the analysis methods in the examples all adopt conventional settings and conventional analysis methods of instruments or equipment.

[0075] The reagents and materials used in this application include:

[0076] Analytical grade ethyl acetate, sodium chloride and anhydrous sodium sulfate (Shanghai McLean Biochemical Technology Co., Ltd.); two polytetrafluoroethylene (PTFE) hydrophobic membranes (diameter 50 mm, pore sizes 0.10 μm and 0.45 μm respectively) and one polyvinylidene fluoride (PVDF) hydrophobic membrane (diameter 50 mm, pore size 0.45 μm) (Haining Delv New Material Technology Co., Ltd.); filter paper (pore size 80 μm) (Xi'an Minghuang Filter Material Co., Ltd.); distilled water (Watson Group); star anise (Wuhan Tianxianghui Condiment Co., Ltd.).

[0077] Instruments and characterization methods used in this application:

[0078] 500mL 250W KDM electric heating mantle (Shandong Juancheng Hualu Electric Heating Instrument Co., Ltd.), round-bottom flask, air condenser, thermometer, distillation head, straight condenser, receiving tube (Tianjin Tianke Glass Instrument Manufacturing Co., Ltd.), iron stand.

[0079] GC-MS instrument (Agilent 5973) chromatographic conditions:

[0080] Inlet temperature: 220℃

[0081] Injection volume: 1 μL

[0082] No split

[0083] Carrier gas: high purity nitrogen (99.999%)

[0084] Column flow rate: 1mL / min

[0085] Chromatographic column: DB5 quartz capillary column 30m×0.25mm×0.25μm

[0086] Program temperature: 40℃, hold for 1 min; increase to 200℃ at a rate of 10℃ / min, hold for 3 min

[0087] Mass spectrometry conditions: EI ion source

[0088] Electron energy: 70eV

[0089] Emission current: 100μA

[0090] Interface temperature: 210℃

[0091] Ion source temperature: 210°C

[0092] Flow scan range: 50~350m / z

[0093] Solvent delay: 4.0min

[0094] Example 1

[0095] Method for extracting star anise essential oil using the extraction device of the present application:

[0096] (1) Grind 15 g of star anise into a particle size of 120 μm using a ball mill and set aside;

[0097] (2) Use a 250 ml round-bottom flask as a water vapor generator, add distilled water that accounts for 3 / 4 of the volume of the flask and 3 zeolite particles into the flask, and install an air condenser at the mouth of the flask;

[0098] (3) Fill the bottom of the air condenser with filter paper, place 15g of crushed star anise powder, and load a single layer of 0.45μm polytetrafluoroethylene (PTFE) hydrophobic membrane on the top. Then press Figure 1 Install the distillation head, condenser, receiving tube, receiving bottle and thermometer as shown. The picture of the completed installation is as follows Figure 3 As shown;

[0099] (4) Allow condensed water to flow in from the lower end of the condenser tube and out from the upper end. Turn on the heating device, control the temperature of the thermometer to 95°C, and observe the phenomenon. After heating for 10 minutes, an oily liquid is observed to flow into the receiving bottle. Adjust the voltage of the heating jacket and control the flow rate of the distillate to 4 seconds per drop. After 90 minutes, when the distillate is clear and transparent, the flow rate decreases, and no oil droplets of organic matter are contained, the end point of the distillation is reached. Turn off the heat source, stop passing condensed water after the device has cooled down, and disassemble the device;

[0100] (5) After the distillate is naturally cooled to room temperature, remove the receiving bottle, add salt to saturate it (add 3.2 g per 10 mL), stir it thoroughly, and let it stand to obtain a mixed solution;

[0101] (6) Pour the mixed solution into a pear-shaped separatory funnel without pouring in solids, add 8 mL of ethyl acetate for extraction, repeat the extraction operation 3 times, discard the water layer, and combine the ester layers. Add an appropriate amount of anhydrous sodium sulfate to the combined ethyl acetate conical flask for drying. Transfer the ester layer to a dry 50 mL round-bottom flask that has been pre-added with zeolite and weighed for total weight, distill, evaporate the ethyl acetate, collect the residue, and obtain star anise essential oil, which is weighed.

[0102] Repeat the above steps for a total of 6 experiments and record the experimental data respectively.

[0103] Example 2

[0104] Method for extracting star anise essential oil using the extraction device of the present application:

[0105] (1) Grind 15 g of star anise into a particle size of 150 μm using a ball mill and set aside;

[0106] (2) Use a 250 ml round-bottom flask as a water vapor generator, add distilled water that accounts for 3 / 4 of the volume of the flask and 2 zeolites into the flask, and install an air condenser at the mouth of the flask;

[0107] (3) Fill the bottom of the air condenser with filter paper, place 15g of crushed star anise powder, and load a single layer of 0.45μm polytetrafluoroethylene (PTFE) hydrophobic membrane on the top. Then press Figure 1 Install the distillation head, condenser, receiving tube, receiving bottle and thermometer as shown. The picture of the completed installation is as follows Figure 3 As shown;

[0108] (4) Allow condensed water to flow in from the lower end of the condenser tube and out from the upper end. Turn on the heating device, control the temperature of the thermometer to 94°C, and observe the phenomenon. After heating for about 10 minutes, an oily liquid is observed to flow into the receiving bottle. Adjust the voltage of the heating jacket and control the flow rate of the distillate to 3 seconds per drop. Maintain for about 90 minutes. When the distillate is clear and transparent, the flow rate decreases, and no oil droplets of organic matter are contained, the end point of the distillation is reached. Turn off the heat source, stop passing condensed water after the device has cooled down, and disassemble the device;

[0109] (5) After the distillate is naturally cooled to room temperature, remove the receiving bottle, add salt to saturate it (add 3 g per 10 mL), stir it thoroughly, and let it stand to obtain a mixed solution;

[0110] (6) Pour the mixed solution into a pear-shaped separatory funnel without pouring in solids, add 8 mL of ethyl acetate for extraction, repeat the extraction operation 3 times, discard the water layer, and combine the ester layers. Add an appropriate amount of anhydrous sodium sulfate to the combined ethyl acetate conical flask for drying. Transfer the ester layer to a dry 50 mL round-bottom flask that has been pre-added with zeolite and weighed for total weight, distill, evaporate the ethyl acetate, collect the residue, and obtain star anise essential oil, which is weighed.

[0111] Repeat the above steps for a total of 6 experiments and record the experimental data respectively.

[0112] Example 3

[0113] Method for extracting star anise essential oil using the extraction device of the present application:

[0114] (1) Grind 15 g of star anise into a particle size of 100 μm using a ball mill and set aside;

[0115] (2) Use a 250 ml round-bottom flask as a water vapor generator, add distilled water that accounts for 2 / 3 of the volume of the flask and 4 zeolites into the flask, and install an air condenser at the mouth of the flask;

[0116] (3) Fill the bottom of the air condenser with filter paper, place 15g of crushed star anise powder, and load a single layer of 0.45μm polytetrafluoroethylene (PTFE) hydrophobic membrane on the top. Then press Figure 1 Install the distillation head, condenser, receiving tube, receiving bottle and thermometer as shown. The picture of the completed installation is as follows Figure 3 As shown;

[0117] (4) Allow condensed water to flow in from the lower end of the condenser tube and out from the upper end. Turn on the heating device, control the temperature of the thermometer to 96°C, and observe the phenomenon. After heating for about 10 minutes, an oily liquid is observed to flow into the receiving bottle. Adjust the voltage of the heating jacket and control the flow rate of the distillate to 5 seconds per drop. Maintain for about 90 minutes. When the distillate is clear and transparent, the flow rate decreases, and no oil droplets of organic matter are contained, the end point of the distillation is reached. Turn off the heat source, stop passing condensed water after the device has cooled down, and disassemble the device;

[0118] (5) After the distillate is naturally cooled to room temperature, remove the receiving bottle, add salt to saturate it (add 3.5 g per 10 mL), stir it thoroughly, and let it stand to obtain a mixed solution;

[0119] (6) Pour the mixed solution into a pear-shaped separatory funnel without pouring in solids, add 8 mL of ethyl acetate for extraction, repeat the extraction operation 3 times, discard the water layer, and combine the ester layers. Add an appropriate amount of anhydrous sodium sulfate to the combined ethyl acetate conical flask for drying. Transfer the ester layer to a dry 50 mL round-bottom flask that has been pre-added with zeolite and weighed for total weight, distill, evaporate the ethyl acetate, collect the residue, and obtain star anise essential oil, which is weighed.

[0120] Repeat the above steps for a total of 6 experiments and record the experimental data respectively.

[0121] Comparative Example 1

[0122] Keeping other operating conditions unchanged, using a conventional extraction device (such as Figure 2 and Figure 4 The steps of Example 1 were repeated for a total of 6 experiments, and the experimental data were recorded respectively.

[0123] Comparative Example 2

[0124] Keeping other operating conditions unchanged, the steps of Example 1 were repeated by replacing the polytetrafluoroethylene hydrophobic membrane with a pore size of 0.45 μm with a polytetrafluoroethylene hydrophobic membrane with a pore size of 0.10 μm. A total of 6 experiments were conducted and the experimental data were recorded respectively.

[0125] Comparative Example 3

[0126] Keeping other operating conditions unchanged, the steps of Example 1 were repeated by replacing the polytetrafluoroethylene hydrophobic membrane with a pore size of 0.45 μm with a polyvinylidene fluoride (PVDF) hydrophobic membrane with a pore size of 0.45 μm. A total of 6 experiments were performed and the experimental data were recorded respectively.

[0127] Experimental Example 1

[0128] Taking Examples 1 to 3 and Comparative Examples 1 to 3 as examples, the distillation time and the power consumption of a single experiment of each group were counted, and the essential oil yield of each group (essential oil yield = essential oil mass / star anise mass × 100%) was calculated, and the average value was taken. The results are shown in Table 1.

[0129] Table 1 Statistics of experimental results of each group

[0130]

[0131]

[0132] As can be seen from Table 1, compared with Comparative Examples 1 to 3, the distillation time and overall experimental duration of Examples 1 to 3 of the present application are shortened, and the energy consumption is lower, and the essential oil yield is also higher, with Example 1 being the most significant. Taking Comparative Example 1 as an example, the traditional extraction device used therein needs to almost dry up the water in the steam generator, which takes about 2 hours to complete, and the extraction amount is not guaranteed, while the present application only takes about 1.5 hours to complete the distillation extraction. At the same time, the shortening of the experimental duration is also accompanied by a reduction in energy consumption. It is calculated that the power consumption of a single experiment is reduced from 0.5kw·h to 0.375kw·h, a year-on-year decrease of 25%. It can be seen that only by adopting the extraction device and extraction method of the present application can the technical effect of the present application be achieved. The use of traditional extraction devices or changing the type and particle size of the polymer membrane cannot achieve the technical effect of the present application.

[0133] Experimental Example 2

[0134] All products of the six experiments in Example 1 and all products of the six experiments in Comparative Example 1 were collected, and the components and contents of the star anise essential oil products in Example 1 and Comparative Example 1 were respectively detected using a GC-MS instrument, and the obtained data were analyzed. The results are shown in Table 2.

[0135] Table 2 Analysis of ingredients and contents of products of Example 1 and Comparative Example 1

[0136]

[0137]

[0138] As shown in Table 2, compared with Comparative Example 1, the composition of the active ingredients in the essential oil product of the present application is basically unchanged, but the content of the main active ingredient anethole is greatly increased, up to 84.12%. It can be seen that the use of the extraction device and extraction method of the present application can effectively promote the dissolution of the active ingredients in star anise essential oil.

[0139] In summary, the extraction device of star anise essential oil provided by the present application changes the star anise filler device into an air condenser to form a partial reflux, and sets a hydrophobic polymer membrane at the water vapor outlet, and utilizes its selective permeability to efficiently obtain star anise oil. The traditional extraction device is optimized, the simple pressurization of the experimental device is realized, and the yield of essential oil is improved while shortening the experimental steam transmission path. The device of the present application has a simple structure, high water vapor utilization rate, and can weaken the emulsification phenomenon. The extraction method used not only saves extraction time, but also reduces energy consumption, conforms to the concept of green development, and improves the essential oil yield of star anise. The GC-MS analysis results show that the composition of the main active ingredients in star anise essential oil is basically unchanged, and the content of the active ingredient anethole is as high as 84.12%.

[0140] The above are only a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. An extraction device for star anise essential oil, characterized in that: It comprises a round-bottom flask (1), an air condenser (2), a distillation head (3), a condenser (4), a receiving tube (5), and a receiving bottle (6); The mouth of the round-bottom flask (1) is connected to the bottom of the air condenser (2); The top of the air condensation tube (2) is connected to the bottom tube of the distillation head (3); The side end tube of the distillation head (3) is connected to the top of the condenser (4); The bottom of the condenser tube (4) is connected to the top of the receiving tube (5); Inserting the tail of the receiving tube (5) into the receiving bottle (6); The top of the air condensation tube (2) is loaded with a polymer membrane (7).

2. The extraction device for star anise essential oil according to claim 1, characterized in that: The bottom of the air condensation tube (2) is loaded with filter paper (8).

3. The extraction device for star anise essential oil according to claim 1, characterized in that: A thermometer (9) is inserted into the top of the distillation head (3).

4. A method for extracting star anise essential oil, characterized in that: The method is carried out using the extraction device according to any one of claims 1 to 3, comprising the following steps: (1) crushing star anise to obtain star anise powder; (2) Add distilled water and zeolite into a round-bottom flask and install an air condenser at the mouth of the flask; (3) Filling filter paper at the bottom of the air condenser, placing the star anise powder on the filter paper, and then loading the polymer film on the top of the air condenser; (4) Install the distillation head, condenser, receiving tube, and receiving bottle in sequence, and insert a thermometer at the top of the distillation head; (5) Condensed water is introduced into the condenser tube from the lower opening and flows out from the upper opening, and the round-bottom flask is heated to start distillation until the distillate is clear and transparent, the flow rate is reduced, and no oil droplets of organic matter are contained, reaching the end point of distillation. The heat source is turned off, and the condensed water is stopped after the device is cooled; (6) After the distillate cools to room temperature, remove the receiving bottle, add salt, stir thoroughly, and let stand to obtain a mixed solution; (7) Pour the mixed solution into a pear-shaped separatory funnel, add ethyl acetate for extraction, repeat the extraction operation 2 to 4 times, discard the water layer, combine the ester layers, dry and distill them in sequence, evaporate the ethyl acetate, collect the residue, and obtain star anise essential oil.

5. The method for extracting star anise essential oil according to claim 4, characterized in that: In step (1), the particle size of the star anise powder is 100 to 150 μm; The star anise powder is used in an amount of 10 to 30 g.

6. The method for extracting star anise essential oil according to claim 4, characterized in that: In step (2), the volume of distilled water added is 2 / 3 to 3 / 4 of the volume of the round-bottom flask; The dosage of the zeolite is 2 to 4 grains.

7. The method for extracting star anise essential oil according to claim 4, characterized in that: In step (3), the pore size of the filter paper is smaller than the particle size of the star anise powder; Preferably, the polymer film is a single-layer film; Preferably, the polymer membrane is a polytetrafluoroethylene hydrophobic membrane; Preferably, the pore size of the polytetrafluoroethylene hydrophobic membrane is 0.4 to 0.5 μm; Preferably, the pore size of the polytetrafluoroethylene hydrophobic membrane is 0.45 μm.

8. The method for extracting star anise essential oil according to claim 4, characterized in that: In step (5), during the distillation process, the thermometer temperature is controlled at 94-96° C.; When oily liquid flows into the receiving bottle, adjust the heating voltage to control the flow rate of the distillate to 3-5s / drop.

9. The method for extracting star anise essential oil according to claim 4, characterized in that: In step (6), the ratio of the salt to the distillate in the receiving bottle is 3-3.5 g:10 mL; The standing time is 10 to 20 minutes.

10. The method for extracting star anise essential oil according to claim 4, characterized in that: In step (7), the amount of ethyl acetate used is 20-40% of the volume of the mixed solution; The extraction time is 10 to 20 minutes per time; Preferably, the drying is carried out using anhydrous sodium sulfate; The amount of anhydrous sodium sulfate used is 15-20% of the mass of the combined ester layer; Preferably, the distillation temperature is 70-90°C; The distillation time is 1 to 2 hours.

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