CN112137157B - A method for extracting a nicotine-rich composition from tobacco leaves - Google Patents

Abstract

The invention discloses a method for extracting a nicotine-rich composition from tobacco leaves, and relates to the technical field of subcritical fluid extraction. The method comprises: (1) washing, drying, and pulverizing tobacco leaves into pieces; (2) pouring the tobacco leaf pieces into an extraction tank of a subcritical propane fluid extraction device to perform front-stage extraction of subcritical propane fluid; (3) removing (4) carrying out the back-end extraction of the subcritical propane fluid; (5) introducing the back-end extract obtained by the back-end extraction into a separation tank; (6) removing the propane in the back-end extract to obtain The composition rich in nicotine; wherein, the extraction conditions of subcritical propane fluid are propane flow rate of 8 to 15 liters/hour, extraction tank pressure of 30 to 55 bar, extraction tank temperature of 30 to 75 ° C; the overall extraction time of subcritical propane fluid is 40 to 90 minutes, and the extraction time in the latter stage is 1/3 to 1/2 of the overall extraction time. By the method provided by the present invention, a nicotine-rich composition can be obtained.

Description

A method of extracting a nicotine-rich composition from tobacco leaves

technical field

The present invention relates to the technical field of subcritical fluid extraction, in particular to a method for extracting a nicotine-rich composition from tobacco leaves.

Background technique

Nicotine, commonly known as nicotine, is an alkaloid that exists in Solanaceae plants (Solanum), an important component of tobacco, and a representative of N choline receptor agonists. It has a role in the central nervous system and can be used medicinally.

To extract nicotine from tobacco leaves, the currently known extraction methods, whether it is water extraction, organic solvent extraction, supercritical fluid extraction, or even subcritical extraction, are used to remove nicotine, not to extract high purity nicotine, and the nicotine content/purity in its removal is not high enough to be used as medicinal nicotine.

US Patent No. 9,004,074 proposes a method for solvent extraction of tobacco using chloroform, dichloromethane or chloroform-dichloromethane mixture to remove nicotine, see item 1 of its patent application scope; but this method does not use subcritical Propane fluid extraction method, and the nicotine content/purity in the removed is not high, so it cannot be used as medicinal nicotine.

U.S. Patent No. 5,497,792 proposes a method for using supercritical fluid to extract nicotine from tobacco, see item 1 of its patent application scope; however, this method does not use subcritical propane fluid extraction, and removes The content/purity of nicotine in the removal is not high enough to be used as medicinal nicotine.

U.S. Patent No. 4,153,063 also proposes a method for using supercritical fluid to extract nicotine from tobacco, see item 1 of its patent application scope; but this method does not use subcritical propane fluid extraction, and The nicotine content/purity in the removal is not high enough to be used as medicinal nicotine.

Taiwan Patent No. I543714 uses supercritical fluid extraction method to perform supercritical fluid extraction on the aqueous extract of tobacco to remove nicotine, see page 16, lines 5 to 7 of its specification; but this method does not use subcritical fluid Propane fluid extraction method, and the nicotine content/purity in the removed is not high, so it cannot be used as medicinal nicotine.

Taiwan No. 201534228 (Patent) Publication, mentions the use of glycerin, water or ethanol to capture/remove nicotine, see paragraph 0054 of the case, this method can reduce the residual rate of nicotine components to 40%, see Item 1 of its patent application scope; however, the method does not use subcritical propane fluid extraction, and the nicotine content/purity in the removed is not high, so it cannot be used as medicinal nicotine.

Chinese Invention Patent Application Publication No. CN 110662436 A mentions the use of carbon dioxide supercritical/subcritical extraction method to remove nicotine, see items 1, 3, and 4 of its patent application scope; but this method uses carbon dioxide supercritical/subcritical extraction The critical extraction method does not use the subcritical propane fluid extraction method, and the nicotine content/purity in the removed is not high, so it cannot be used as medicinal nicotine.

China Invention Patent Authorization Announcement No. CN 102090710 B, mentions that the subcritical extraction method is used to extract tobacco leaves, and the extraction solvent can be propane. "Nicotine", see paragraph 008 of its specification; however, although this method mentions that subcritical propane fluid extraction can be used, the nicotine content/purity in the removed is not high enough to be used as medicinal nicotine.

Chinese Invention Patent Application Publication No. CN 001302568 A mentions that tobacco leaves are extracted by subcritical extraction method, and the extraction solvent can be propane. Different components such as aromatic absolute oil components, nicotine, solanesol, etc. in the extraction and distillation tobacco, please refer to item 1 of its patent application scope; that is, although this method mentions that the subcritical propane fluid extraction method can be used, but the The nicotine content/purity is not high enough to be used as medicinal nicotine.

China Invention Patent Authorization Announcement No. CN 001141044 C, mentions that the subcritical extraction method is used to extract tobacco leaves, and the extraction solvent can be propane. Different components such as aromatic absolute oil components, nicotine, solanesol, etc. in the extraction and distillation tobacco, please refer to item 1 of its patent application scope; that is, although this method mentions that the subcritical propane fluid extraction method can be used, but the The nicotine content/purity is not high enough to be used as medicinal nicotine.

Chinese Invention Patent Authorization Announcement No. CN 101247739 B, mentions that tobacco solutes are extracted from tobacco with an extraction solvent, and then an entrained solvent (propylene glycol, triacetin, and/or glycerol) is used to remove tobacco solutes from the extraction solvent. , see item 1 of its patent application scope, wherein the extraction solvent is a supercritical fluid, see item 2 of its patent application scope; but this method uses carbon dioxide supercritical extraction method, not subcritical propane fluid extraction method, and its removal In the removed tobacco solute, the nicotine is not of high purity and cannot be used as medicinal nicotine.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is the existing method for extracting nicotine from tobacco leaves, and the nicotine content in the extracted product is low and cannot be used medicinally.

One object of the present invention is to provide a method for extracting a nicotine-rich composition from tobacco leaves.

Another object of the present invention is to provide a subcritical propane fluid extraction method for extracting a nicotine-rich composition from tobacco leaves.

Another object of the present invention is to provide a multiple extraction method utilizing subcritical propane fluid to obtain a nicotine-rich composition.

In order to solve the above problems, the present invention proposes the following technical solutions:

A method for extracting a nicotine-rich composition from tobacco leaves, comprising the steps of:

(1) the tobacco leaves are washed, dried, and then pulverized into pieces;

(2) pour this tobacco leaf fragment into the extraction tank of subcritical propane fluid extraction equipment, carry out the front section extraction of subcritical propane fluid;

(3) remove the extract of front-end extraction;

(4) carry out the back-end extraction of subcritical propane fluid;

(5) the back-end extraction liquid obtained by back-end extraction is introduced into a separation tank; and

(6) remove the propane in the back-end extract to obtain a composition rich in nicotine;

Wherein, the subcritical propane fluid extraction conditions are propane flow rate of 8 to 15 liters/hour, extraction tank pressure of 30 to 55 bar, extraction tank temperature of 30 to 75 °C; The extraction time is 1/3 to 1/2 of the overall extraction time.

The technical scheme of the present invention can further contain a propane recovery step to recover the propane separated from the separation tank, so as to achieve the purpose of low cost and environmental protection.

The tobacco leaf can be any variety well-known to those skilled in the art, preferably safflower leaf (scientific name: Nicotiana forgetiana) or yellow-flowered tobacco (scientific name: Nicotiana rustica), more preferably safflower leaf.

The tobacco leaf fragments are used to improve the extraction effect. If the fragments are too large, the extraction effect is poor. Generally speaking, 1-100 square millimeters (mm ² ) are preferred.

The pressure of the extraction tank is 30-55 bar, preferably 35-50 bar, more preferably 40-45 bar. The extraction tank pressure is slightly lower than 30 bar, or slightly higher than 55 bar, which is not completely impossible, but due to the relatively low yield of the latter stage extract, or its nicotine purity is reduced, such as at the edge of 90%, resulting in quality control (90 %) yield decreased.

The temperature of the extraction tank is 30-75°C, preferably 45-70°C, more preferably 55-65°C. The temperature of the extraction tank is slightly lower than 30°C, or slightly higher than 75°C, which is not completely unfeasible, but due to the relatively low yield of the latter-stage extract, or its reduced nicotine purity, for example, at the edge of 90%, resulting in quality control (90%) %), see Example 15.

The propane flow rate is 8 to 15 liters/hour, preferably 9 to 14 liters/hour, and more preferably 10 to 13 liters/hour; the propane flow rate of the extraction tank is slightly lower than 8 liters/hour, or slightly higher. At 15 liters/hour, it is not completely unfeasible, but the yield of the quality control (90%) is reduced due to the relatively low yield of the back-end extract, or its reduced nicotine purity, for example, at the edge of 90%.

The pressure of the separation tank may not be lower than the pressure of the propane storage tank, generally speaking, it is 8-10 bar.

The temperature of the separation tank may be higher than the boiling point of propane, generally above room temperature, preferably 40-60°C.

The overall extraction time of the above-mentioned subcritical propane fluid is 40 to 90 minutes. The so-called "overall extraction time of the subcritical propane fluid" herein refers to the sum of the extraction time of the previous stage and the extraction time of the latter stage, hereinafter referred to as the overall extraction time. The length of the overall extraction time depends on the extraction conditions, and the propane flow rate is the determining factor of the overall extraction time. Generally speaking, the larger the propane flow rate, the shorter the overall extraction time; on the contrary, the smaller the propane flow rate, the longer the overall extraction time. Taking the propane flow rate of 8 liters/hour as an example, the overall extraction time is 90 minutes; taking the propane flow rate of 15 liters/hour as an example, the overall extraction time can be 40 minutes.

The ratio of the extraction time in the latter stage of the subcritical propane fluid extraction to the overall extraction time (R value) depends on the extraction conditions, and the propane flow rate is especially the determining factor of the R value. The value is smaller; on the contrary, the propane flow rate is smaller, and the R value is larger. Taking the propane flow rate of 8 liters/hour as an example, the R value is 1/3; taking the propane flow rate of 15 liters/hour as an example, the R value is 1/2.

Compared with the prior art, the technical effects that the present invention can achieve include:

The method for extracting a nicotine-rich composition from tobacco leaves provided by the present invention adopts a subcritical propane fluid extraction method to extract tobacco leaves to obtain a nicotine-rich composition. The innovation of this method is: (1) the present invention adopts subcritical propane fluid to extract tobacco leaves, which can obtain nicotine composition with high efficiency; (2) the subcritical propane fluid of the present invention extracts tobacco leaves in stages, especially the latter stage extraction , the composition rich in nicotine can be obtained; (3) the present invention is to extract tobacco leaves with subcritical propane fluid under specific temperature and pressure, and the composition rich in nicotine can be obtained; (4) the subcritical propane provided by the present invention The fluid extraction of tobacco leaves adopts the method of segmental extraction; based on the above 4 points, the method provided by the present invention can obtain a nicotine-rich composition; (5) the method provided by the present invention can recover propane. Based on the above (1) to (4), the method provided by the present invention can obtain a rich nicotine composition; based on the above (5), the method provided by the present invention can achieve the purpose of low cost and environmental protection.

Description of drawings

Figure 1 is a schematic block diagram of a subcritical fluid extraction equipment.

FIG. 2 is the GCMS spectrum of the back-end extract (nicotine-rich composition) extracted in Example 1. FIG.

FIG. 3 is the GCMS spectrum of the back-end extract (nicotine-rich composition) extracted in Example 2. FIG.

FIG. 4 is the GCMS spectrum of the back-end extract (nicotine-rich composition) extracted in Example 4. FIG.

FIG. 5 is the GCMS spectrum of the back-end extract (nicotine-rich composition) extracted in Example 6. FIG.

FIG. 6 is the GCMS spectrum of the back-end extract (nicotine-rich composition) extracted in Example 7. FIG.

Fig. 7 is the GCMS spectrum of the back-end extract (nicotine-rich composition) obtained by the extraction in Example 10.

Fig. 8 is the GCMS chart of the back-end extract (nicotine-rich composition) obtained by the extraction in Example 11.

9 is the GCMS spectrum of the back-end extract (nicotine-rich composition) obtained in Example 14.

Fig. 10 is the GCMS chart of the back-end extract (nicotine-rich composition) obtained by the extraction in Example 15.

11 is the GCMS spectrum of the first-stage extract obtained by the first-stage extraction in Example 1.

reference number

100 propane storage tank, 200 extraction tank, 300 separation tank, 400 propane recovery device, 500 propane conveying device, 510 check valve, 520 booster pump, 530 preheater, 610 first control valve, 620 second control valve.

Detailed ways

The technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and similar component numbers in the accompanying drawings represent similar components. Obviously, the embodiments to be described below are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

Understandably, the term "nicotine-enriched composition" of the present invention refers to the product after removal of propane in the back-end extract, also referred to as "back-end extract".

In other embodiments, in the method for extracting a nicotine-rich composition from tobacco leaves provided by the present invention, the extraction conditions of the pre-extraction and post-extraction may be the same or different, but the extraction conditions of the pre-extraction and post-extraction should be Comply with the subcritical propane fluid extraction conditions: propane flow rate 8-15 liters/hour, extraction tank pressure 30-55 bar, extraction tank temperature 30-75 °C; the overall extraction time of subcritical propane fluid is 40-90 minutes, and the latter extraction The time is 1/3 to 1/2 of the overall extraction time.

The method for extracting a nicotine-rich composition from tobacco leaves provided by the present invention adopts subcritical extraction equipment for extraction. In one embodiment, the subcritical fluid extraction equipment is shown in Figure 1.

In FIG. 1, 100 is a propane storage tank for storing propane.

200 is an extraction tank, for putting into the tobacco leaf pieces to be extracted, and after introducing the subcritical propane fluid, carry out subcritical propane fluid extraction, to extract the composition rich in nicotine, obtain the propane (subcritical) rich in nicotine. critical fluid) extract.

500 is a propane conveying device for connecting the propane storage tank 100 and the extraction tank 200 .

300 is a separation tank for removing propane in the nicotine-rich propane (subcritical fluid) extract to obtain a nicotine-rich composition.

610 is a first control valve, which is arranged between the extraction tank 200 and the separation tank 300, and is used for introducing the extraction liquid in the extraction tank 200 into the separation tank 300.

620 is a second control valve, which is connected to the separation tank 300. Generally speaking, the second control valve 620 is located at the lower end of the separation tank 300. In the present invention, the second control valve 620 is used to open the second control valve 620 when the first-stage extraction is completed, to remove the first-stage extract from the separation tank 300, and then close the second control valve 620 to continue the second-stage extraction. , when the back-end extraction is completed, after removing the propane in the back-end extract, the second control valve 620 is opened to collect the back-end extract, that is, a nicotine-rich composition (product) is obtained.

400 is a propane recovery device installed between the propane storage tank 100 and the separation tank 300 for recovering propane discharged from the separation tank 300 and introducing the recovered propane into the propane storage tank 100 .

In other embodiments, the propane delivery device 500 includes a check valve 510, a booster pump 520, and a preheater 530.

Among them, the booster pump 520 is used to pressurize the pressure of the propane storage tank 100 (generally 8-10 bar) to the pressure of the extraction tank 200; the check valve 510 is used to prevent the propane from rushing to the propane storage tank 100; preheating Vessel 530 is used to preheat the propane to the temperature of extraction tank 200 .

In other embodiments, the preheater 530 can also be changed into a hot water jacket, which surrounds the periphery of the extraction tank 200 to achieve the purpose of controlling the temperature of the extraction tank 200. Also, in the same way, a hot water jacket can be added around the separation tank 300 to achieve the purpose of controlling the temperature of the separation tank 300.

The subcritical extraction equipment used in the present invention can further add a deodorizing device (not shown in the figure) in the propane recovery device 400 for removing the odor in the propane to be recovered.

The subcritical extraction equipment used in the present invention may further be provided with a discharge valve (not shown in the figure) at the top of the extraction tank 200, so as to remove the existing air in the extraction tank 200.

The subcritical extraction equipment used in the present invention can further add a pressure detector, a temperature detector, a propane concentration detector, a safety valve, an electric hot water microcomputer controller (not marked in the figure), etc. The pressure/temperature of the extraction tank 200, the pressure/temperature of the separation tank 300, and the pressure of the propane storage tank 100 are controlled, and gas explosion is prevented.

Example 1:

Tobacco leaves are washed, dried, and then pulverized into 1-10 mm pieces. Weigh 700 grams of tobacco leaf fragments, pour them into the extraction tank of the subcritical propane fluid extraction equipment, and exhaust the original air in the equipment; inject propane (8 bar) with the same pressure as the propane storage tank; set the extraction conditions as: propane flow rate 12 liters /hour, extraction tank pressure 45bar/temperature 65℃, separation tank pressure 8-10bar/temperature 50℃. Carry out propane subcritical extraction under the above conditions for half an hour (this is the first stage extraction), take out 89.0 grams of the first stage extract, its GC-MS spectrum is shown in Figure 11, wherein the nicotine content is 32.23%, the purity is not high, the first stage extract can be used for Other purposes, or further purification; continue to carry out the subcritical extraction of propane for half an hour (this is the back-end extraction), after removing the propane in the back-end extract, 19.2 g of the back-end extract (product) is obtained, and its GC-MS spectrum See Figure 2, where the nicotine content is as high as 94.40%.

Examples 2 to 15

Similar to embodiment 1, but the subcritical extraction conditions are slightly different, see Table 1, and the amount and purity of the obtained product are also shown in Table 1. The GC-MS spectra of Examples 1, 2, 4, 6, 7, 10, 11, 14, and 15 are shown in Figures 2, 3, 4, 5, 6, 7, 8, 9, and 10, respectively.

Table 1: SPE conditions and product weight (g) and purity (%) of Preliminary Examples 1-14.

As can be seen from Table 1, adopt the method for extracting nicotine composition from tobacco leaves provided by the present invention, utilize subcritical propane fluid to carry out segmental extraction, and the nicotine purity in the obtained extraction product (rear section extract) is greater than 90%, which can be used for medicinal purposes. .

In the foregoing embodiments, the description of each embodiment has its own emphasis. For the part that is not described in detail in a certain embodiment, reference may be made to the relevant descriptions of other embodiments.

The above are the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of various equivalent modifications within the technical scope disclosed by the present invention. or replacement, these modifications or replacements should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims (8)

1. a method for extracting rich nicotine composition from tobacco leaf, is characterized in that, comprises the following steps: (1) the tobacco leaves are washed, dried, and then pulverized into pieces; (2) pour this tobacco leaf fragment into the extraction tank of subcritical propane fluid extraction equipment, carry out the front section extraction of subcritical propane fluid; (3) remove the extract of front-end extraction; (4) carry out the back-end extraction of subcritical propane fluid; (5) the back-end extraction liquid obtained by back-end extraction is introduced into a separation tank; and (6) remove the propane in the back-end extract to obtain a composition rich in nicotine; Wherein, the subcritical propane fluid extraction conditions are propane flow rate of 8 to 15 liters/hour, extraction tank pressure of 30 to 55 bar, extraction tank temperature of 55 to 65 °C; The extraction time is 1/3 to 1/2 of the overall extraction time. 2 . The method for extracting a nicotine-rich composition from tobacco leaves according to claim 1 , wherein the propane flow rate is 9-14 liters/hour. 3 . 3. The method for extracting a nicotine-rich composition from tobacco leaves according to claim 2, wherein the flow rate of the propane is 10-13 liters/hour. 4. The method for extracting a nicotine-rich composition from tobacco leaves according to claim 1, wherein the extraction tank has a pressure of 30-50 bar. 5. The method for extracting a nicotine-rich composition from tobacco leaves according to claim 4, wherein the extraction tank has a pressure of 40-45 bar. 6 . The method for extracting a nicotine-rich composition from tobacco leaves according to claim 1 , wherein the tobacco leaf fragments are 1-100 mm ² in size. 7 . 7. The method for extracting a nicotine-rich composition from tobacco leaves according to claim 1, wherein the pressure of the separation tank is 8-10 bar. 8 . The method for extracting a nicotine-rich composition from tobacco leaves according to claim 1 , wherein the temperature of the separation tank is 40-60° C. 9 .

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