A method for stepwise extraction of high purity nicotine and high purity solanesol from waste tobacco

Abstract

The application discloses a method for step-by-step extraction of high-purity nicotine and high-purity solapinol from waste tobacco, and the preparation method comprises the following steps: heating and extracting a water solution of dried waste tobacco raw materials, adopting membrane interception for the filtrate, and then performing acidification treatment and membrane concentration, so as to obtain nicotine salt concentrated solution with a purity of 40-45%. Then, alkali treatment, organic solvent extraction and reduced-pressure distillation are performed, so as to obtain high-purity nicotine with a purity of greater than 99%. After the nicotine is extracted, the mixed residue is subjected to alkali liquor saponification treatment, then is immersed by using an organic solvent, and the extraction liquid is recovered to obtain an extract, the extract is subjected to organic solvent dissolution, cooling crystallization, extraction, activated carbon decoloration and membrane molecular interception, so as to obtain crude solapinol, and the crude solapinol is subjected to crystallization and recrystallization treatment, so as to obtain solapinol with a purity of greater than 95%. The method obviously improves the utilization rate of tobacco, effectively solves the problems of excessive organic solvent in the nicotine extraction process, large energy consumption in the production process, too many waste materials, complex production process and the like, reduces the production cost, and is suitable for large-scale production.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of waste tobacco recycling, in particular to a method for step-by-step extraction of high-purity nicotine and high-purity solapinol from waste tobacco. BACKGROUND

[0002] Tobacco contains a variety of active substances, and more than 3000 compounds have been identified, among which important compounds such as solapinol, nicotine, tobacco protein, and tobacco pectin have wide applications in chemical industry, medicine, agriculture, etc., and thus have important development and utilization value. Extracting active substances from waste tobacco and developing and utilizing them can not only make waste tobacco into raw materials needed for production, but also effectively reduce environmental pollution, in line with the concept of green development. Solapinol is a long-chain terpene alcohol, and its content in tobacco is about 0.3%-0.8%. Solapinol is also an important pharmaceutical intermediate, an irreplaceable component of ubiquinone drug intermediates, and a natural raw material irreplaceable for synthesis of side chains of vitamin K and coenzyme Q10, and synthesis of anti-ulcer drugs and anticancer drugs. Crude solapinol cannot be directly used as a pharmaceutical raw material, and the content of solapinol used as a raw material should be above 90%, so preparing solapinol with a purity higher than 90% is the key to in-depth research and development of solapinol. Moreover, tobacco contains a variety of alkaloids, and more than 40 alkaloids have been isolated and identified, among which nicotine has the highest content, accounting for about 95% of the total amount of tobacco alkaloids. Nicotine, also known as nicotine, is a widely used alkaloid. Nicotine can produce certain physiological stimulation on human body, thereby producing addiction, which is the main factor that makes tobacco have commodity value. In addition, nicotine is widely used in fine chemical industry, pharmaceutical industry, organic synthesis, national defense industry, and agriculture. A small amount of nicotine can stimulate the central nervous system of the human body, have the effects of making people calm and anti-depression, and relieve nervous emotions, and can be used for developing drugs for treating cardiovascular diseases, skin diseases, snake venom, insect bite, and unknown swelling poison, etc.; citric acid nicotine prepared from nicotine is also a main component for producing high-quality cigarette quality improver; nicotine with a content of 40% can be used to prepare high-efficiency insecticides and biological pesticides without residues and public hazards for producing crops such as grain, oil, vegetables, and fruits. In recent years, with the rapid expansion of the application field of nicotine products, the demand for natural nicotine in the market is also increasing. Extracting nicotine and solapinol and other substances from waste tobacco to obtain natural active substances in line with green health standards not only has high economic value and brings new opportunities for enterprises, but also makes certain contributions to the construction of a resource-saving and environment-friendly society.

[0003] In recent years, the utilization of waste tobacco mainly includes direct use as raw material to produce organic fertilizer through fermentation; in addition, nicotine and solanesol and other high value-added deep processing products are extracted first, and then the remaining residues are used as raw materials to produce organic fertilizer. At present, the organic solvent extraction method is generally used to produce nicotine, and the large-scale application of solvents not only causes pollution, but also the low yield of solvent process, the residual solvent affects the quality of nicotine, and the purity of the product is not very high.

[0004] The patent with publication number CN111170989A uses aquaporin or polyamide membrane for positive pressure osmosis concentration, the main purpose of which is to remove water from the water vapor distillation nicotine system, and the membrane here only plays a concentration role. Moreover, the final product obtained is nicotine sulfate with a mass percentage concentration of 40%-60%, and the purity is low. The patent with publication number CN112384504A directly heats and concentrates the obtained nicotine sulfate, which has the disadvantage of high energy consumption, and the nicotine obtained by this method generally has a purity of less than 90%, which cannot meet the demand for high-purity nicotine (>99%) on the market. The patent with publication number CN114605382A uses alkalization treatment of nicotine sulfate first, and then uses organic solvent extraction to extract nicotine. In the alkalization extraction process, a large amount of water-soluble impurities such as organic acids, tannins, water-soluble polysaccharides and proteins are also extracted out. Many salts of these substances are emulsifiers, which can change the hydrophilic-lipophilic balance (HLB) value of the extraction equilibrium system, making the phase separation interface unclear, and the emulsification phenomenon is serious, which easily causes difficulty in organic solvent extraction separation. At the same time, in the extraction process, part of these substances also transfer to the organic solvent, increasing the impurities in the system and reducing the purity of nicotine. At the same time, the process still uses heat concentration to produce nicotine, which also has the problem of high energy consumption. The patent with publication number CN104725351A does not use organic solvent, but the evaporation concentration and alcohol precipitation process used in this method involves a large amount of water thermal evaporation operation, which causes very high energy consumption in the production process, further increasing the production cost. Moreover, the widespread use of high-pressure steam also has certain operation risks. Moreover, the above research only extracts nicotine from medicinal herbs, and solanesol, an active substance with important development value, is not extracted, which causes great waste of resources. In summary, the existing nicotine preparation methods have the problems of low nicotine purity, high energy consumption, high cost, complex production process, high operation risk, etc., and moreover, the solanesol in the raw material is not extracted synchronously, causing the problem of waste of natural product resources.

[0005] Patent with publication number CN104086425 studies a method for simultaneous extraction of chlorogenic acid, solanesol, nicotine and rutin. The method uses ethanol as a solvent to extract the four substances simultaneously, and then uses a step-by-step separation method to achieve it. The obtained nicotine is 40% nicotine sulfate, and the obtained solanesol is also a crude product. If further purification is needed, column chromatography is required. Patent with publication number CN103342628A discloses a method for simultaneous extraction of nicotine and solanesol. Alkaline ethanol is used to extract nicotine and solanesol simultaneously, and then nicotine and solanesol are separated by acidification and extraction. Solanesol purification uses column chromatography, and nicotine purification uses water vapor distillation. The obtained nicotine has a purity of 98%. Patents with publication numbers CN105541557, CN105646150, CN1931812 and 114591142 disclose a method for extracting solanesol using crystallization and column chromatography. Patent with publication number CN1712392 discloses a method for extracting solanesol using solvent extraction, saponification, crystallization and column chromatography. Patent with publication number CN113264812 discloses a method for extracting solanesol using solvent extraction and silica gel column chromatography, obtaining solanesol with a purity of about 75%. Patent with publication number CN1817834 discloses a method for extracting solanesol using supercritical extraction and silica gel column chromatography, obtaining solanesol with a purity of more than 95%. Patent with publication number CN1810747 discloses a method for extracting solanesol using solvent extraction and macroporous adsorption resin column chromatography, obtaining solanesol with a purity of more than 90-95%. Patent with publication number CN109824482 discloses a method for preparing solanesol using solvent extraction and liquid phase preparation, which can obtain solanesol with a purity of more than 90%. Patent with publication number CN108285405 discloses a method for extracting solanesol using solvent extraction and supercritical extraction, obtaining solanesol with a purity of less than 50%. Patent with publication number CN1724492 discloses a method for extracting solanesol using solvent extraction, saponification and extraction, obtaining solanesol with a purity of less than 30%. Patent with publication number CN101759527 discloses a method for extracting solanesol using crude solanesol as raw material, saponification, low-temperature crystallization, adsorption decolorization and low-temperature re-crystallization, obtaining solanesol with a content of 90%. Patent with publication number CN1919816 discloses a method for preparing solanesol by solvent extraction, saponification, extraction and crystallization, obtaining solanesol with a content of 90-92%. Patent with publication number CN108046990 discloses a method for extracting solanesol using solvent extraction, saponification, extraction and metal ion precipitation, which uses noble silver ion as a complexing agent, increasing the production cost. From the above solanesol extraction and purification research, it is difficult to obtain solanesol with a purity of more than 90% using general solvent extraction, extraction and crystallization processes. If higher purity solanesol is desired, column chromatography or silver ion precipitation methods can be used.The column chromatography has poor stability and is difficult to scale up, and the silver ion precipitation method has high cost and is difficult to recover the metal silver.

[0006] In summary, a method for industrial production is needed to extract high-purity nicotine and high-purity solanesol (>95%) at the same time. SUMMARY

[0007] To solve the problems in the prior art, the application provides a method for step-by-step extraction of high-purity nicotine and high-purity solanesol from waste tobacco, which can extract nicotine and solanesol from tobacco raw materials step by step, solves the problems of excessive use of organic solvents, high energy consumption, many impurities, low purity, and complex production process during the extraction of nicotine from waste tobacco, and solves the problems of low purity of solanesol and inability to be used as a medicinal raw material for further processing. The application effectively improves the purity of the extracted nicotine and solanesol, reduces the production cost, simplifies the process route, and is suitable for large-scale production.

[0008] To achieve the above-mentioned purposes, the application adopts the following specific solutions:

[0009] A method for step-by-step extraction of high-purity nicotine and high-purity solanesol from waste tobacco, mainly comprising the following steps:

[0010] Step one, the waste tobacco is crushed, 6-8 times the mass of water of the waste tobacco is added to the crushed waste tobacco, and the waste tobacco is extracted at a temperature of 40-60 DEG C for 2-3 times, each time for 2-4 h; the extraction liquid obtained each time is combined, the combined extraction liquid is coarsely filtered to obtain filter residue I and filtrate I, the filtrate I is nicotine concentrate, the extracted tobacco residue and the filter residue I obtained by coarse filtration are combined to obtain a mixed residue, and the mixed residue is the raw material for extracting solanesol;

[0011] Step two, the filtrate I is acidified by using an acid solution I with a pH value of 1-3, so that the pH of the system after acidification is less than or equal to 5; then filtering treatment is performed to obtain a nicotine salt concentrate with a purity of 40-45%;

[0012] Step three, the pH value of the nicotine salt concentrate is adjusted to 11-13 by using an alkali solution I, then the nicotine salt concentrate is extracted 2-3 times by using an organic solvent I, and the organic solvent extraction liquid is collected; wherein the volume of the organic solvent I is 1 / 3-1 / 2 of the volume of the solution to be extracted;

[0013] Step four, the organic solvent extraction liquid is subjected to vacuum distillation by using a rectification column system, and the organic solvent and nicotine are collected respectively, and the obtained nicotine is high-purity nicotine with a purity of more than 99%;

[0014] Step five, the mixed slag obtained in step one is directly subjected to saponification treatment with an alkaline solution II having a pH value of 10-12, then 8-10 times the mass of the mixed slag of organic solvent II is added for heating extraction for 2-3 times, the extraction time of each time is 2-4 h, the extraction temperature is 40-60℃, the extraction liquid obtained each time is combined, the combined extraction liquid is subjected to coarse filtration, to obtain filter residue II and filtrate II, the filter residue II can be used as an organic fertilizer raw material, the filtrate II is subjected to solvent recovery under reduced pressure under the conditions that the concentration temperature is 40-60℃ and the concentration pressure is 1000-5000 Pa, to obtain an extract;

[0015] Step six, the extract is dissolved in an organic solvent III, heated to micro-boiling, prepared into a saturated solution, filtered while hot, to obtain a filtrate III, then the filtrate III is cooled to crystallize at a temperature of 8-12℃ for 24-36 h, after crystallization, filtration is performed to remove waxes, to obtain a filtrate IV;

[0016] Step seven, the filtrate IV is added with an acid solution II having a pH value of 2-4 for extraction, the extraction is performed for 2-3 times, to obtain an organic phase; the organic phase is concentrated under the conditions that the concentration temperature is 40-60℃ and the concentration pressure is 1000-5000 Pa, to obtain a crude solanesol crude extract;

[0017] Step eight, the crude solanesol crude extract is dissolved in an organic solvent IV, prepared into a solution, then activated carbon having a mass of 1 / 6-1 / 3 of the mass of the organic phase is added for adsorption treatment, then subjected to membrane molecular cut-off concentration treatment, to obtain a solanesol crude extract;

[0018] Step nine, the solanesol crude extract is crystallized at a temperature of-5℃ to-40℃ for 12-24 h, plate and frame filtration is performed, to obtain light yellow solanesol crystals; the light yellow solanesol crystals are dissolved in an organic solvent V, prepared into a saturated solution, then recrystallized at a temperature of-5℃ to-40℃ for 12-24 h, to obtain solanesol having a purity of greater than 95%.

[0019] Further, in step one, the combined extraction liquid is subjected to coarse filtration by using a plate and frame filter press combined with a microfiltration membrane.

[0020] Further, in step two, the system after acidification is first subjected to coarse filtration by using a plate and frame filter press combined with a microfiltration membrane, then subjected to membrane filtration treatment by using a microfiltration membrane, an ultrafiltration membrane, a nanofiltration membrane or a reverse osmosis membrane, the water molecules removed by membrane cut-off can be reused as extraction water.

[0021] Further, in step three, the alkaline solution I used is any one or several of KOH, NaOH, CaO, Ca(OH)2, ammonia water and Na2CO3.

[0022] Further, in step three, the organic solvent I is any one or several of n-hexane, diethyl ether, ethyl acetate, chloroform, and petroleum ether.

[0023] Further, in step four, the organic solvent extraction liquid is subjected to vacuum distillation by using a rectification column system, and the organic solvent is collected at 40-60 DEG C and the nicotine is collected at 150-160 DEG C; the collected organic solvent can be reused after being recovered by rectification.

[0024] Further, in step five, the alkali solution II is NaOH, KOH or Ca(OH)2, and the water content in the mixed residue after saponification treatment is kept at 80-150%.

[0025] Further, the organic solvent II to the organic solvent V is any one or several of n-hexane, chloroform, ethyl acetate, ethanol, methanol, acetone, and No. 6 solvent oil.

[0026] Further, the acid solution I or the acid solution II is hydrochloric acid or sulfuric acid, wherein the volume of the acid solution II is 1 / 2-1 times the volume of the filtrate IV.

[0027] Further, in step eight, a microfiltration membrane, an ultrafiltration membrane or a nanofiltration membrane is used for molecular cut-off.

[0028] Beneficial effects:

[0029] 1) The utilization rate of raw materials is greatly improved: in the present application, nicotine is first extracted by water, and then solvents are used to extract solanesol after saponification treatment; the rational utilization of tobacco raw materials is realized in the extraction process, the waste of resources is reduced, the tobacco raw materials are fully utilized, and the cost is saved. According to the annual processing of 10000 tons of waste tobacco raw materials, more than 100 tons of high-purity nicotine with a purity of more than 99% and 30 tons of solanesol with a purity of more than 95% can be obtained, and the economic benefits are maximized.

[0030] 2) The energy consumption is significantly reduced by using a membrane, and the operation steps are simplified: in the present application, membrane filtration and concentration process is used to replace the traditional heating evaporation and concentration to remove water, and the method of removing macromolecular impurities such as protein polysaccharide by molecular cut-off, so that the energy consumption in the whole production process is greatly reduced. In addition, the tobacco residue after extracting nicotine does not need to be dried for use as raw material for extracting solanesol, which not only simplifies the process, but also greatly reduces the energy consumption. According to a processing scale of 10000 tons of waste tobacco raw materials per year, more than 25 million yuan of energy consumption expenditure can be saved per year; it meets the requirements of national green and low-carbon production. In the process of nicotine purification, polysaccharide and protein are removed by molecular cut-off, and then the system is subjected to alkalization distillation, acid water absorption and other processes, so that most of the emulsified impurities in the system are removed, and the subsequent operation is simplified.

[0031] 3) The purity of the product is greatly improved: In the process of nicotine extraction, the membrane molecules are intercepted, combined with water vapor distillation, organic solvent extraction, etc. The production process is simplified, the nicotine purity is improved, and high-purity nicotine with a purity of more than 99% is obtained. In the solavane extraction process, through solvent extraction, dissolution, activated carbon adsorption, membrane filtration, crystallization and other operations, the solavane purity is greater than 95%, which fully meets the requirements of solavane raw materials for pharmaceutical intermediates.

[0032] 4) Almost no waste is produced in the production process: From the production process, it can be seen that the tobacco residues after extracting nicotine and solavane can be used as raw materials for bio-organic fertilizer. The water produced in the molecular interception process during nicotine extraction can be used as an extraction solvent for extracting nicotine from raw materials; the polysaccharides and proteins removed by membrane molecular interception can be processed into feed; the organic solvent used for extraction can be recovered and reused after rectification. The organic solvents used in the solavane extraction process can be recycled, with a recovery rate of more than 90%. Therefore, almost "zero" emissions can be achieved in the entire production process, meeting the requirements of the state for environmental protection. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 The process flow diagram for step-by-step extraction of high-purity nicotine and high-purity solavane in Example 1 is shown. DETAILED DESCRIPTION

[0034] The technical solutions of the present application will be described in detail below with specific examples. Obviously, the described examples are only a part of the embodiments of the present application, not all. Based on the examples in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0035] First of all, it needs to be pointed out that the waste tobacco used in the present application includes tobacco stems and waste tobacco leaves generated during tobacco harvesting, as well as tobacco residues and broken ends generated during the processes of re-drying, preparing cigarettes and packaging and transportation, which cannot be used as raw materials for cigarette production.

[0036] The present application provides a method for step-by-step extraction of high-purity nicotine and high-purity solavane from waste tobacco, which mainly comprises the following steps:

[0037] Step one, the waste tobacco is crushed to 10-20 mesh, water is added to the crushed waste tobacco, the amount of water is 6-8 times the mass of the waste tobacco, the extraction is carried out 2-3 times at a temperature of 40-60℃, and the extraction time is 2-4 hours each time; the extraction liquid obtained each time is combined, and the combined extraction liquid is coarsely filtered by using a plate and frame filter press combined with a microfiltration membrane to obtain filter residue I and filter liquid I, the filter liquid I is a nicotine concentrate, the filter residue I obtained by coarsely filtering the extraction residue and the filter residue I is combined to obtain a mixed residue, and the mixed residue is a raw material for extracting solanesol;

[0038] Step two, the filter liquid I is acidified by using an acid solution I (hydrochloric acid or sulfuric acid) with a pH value of 1-3, so that the pH value of the acidified system is ≤5; then the acidified system is coarsely filtered by using a plate and frame filter press combined with a microfiltration membrane, and then the membrane filtration treatment is carried out by using a microfiltration membrane, an ultrafiltration membrane, a nanofiltration membrane or a reverse osmosis membrane to remove the water molecules and small molecular organic impurities with large and small molecular weights in the nicotine, so that a nicotine salt concentrate with a purity of 40-45% is obtained; the water molecules removed by the membrane can be reused as extraction water;

[0039] Step three, the pH value of the nicotine salt concentrate is adjusted to 11-13 by using an alkali solution I (any one or several of KOH, NaOH, CaO, Ca(OH)2, ammonia water and Na2CO3), and then the nicotine salt concentrate is extracted 2-3 times by using an organic solvent I (any one or several of n-hexane, diethyl ether, ethyl acetate, chloroform and petroleum ether), and the organic solvent extraction liquid is collected; wherein, the volume of the organic solvent I is 1 / 3-1 / 2 of the volume of the solution to be extracted;

[0040] Step four, the organic solvent extraction liquid is subjected to reduced pressure distillation by using a rectification column system, the organic solvent is collected at a temperature of 40-60℃, and the nicotine is collected at a temperature of 150-160℃, and the obtained nicotine is high-purity nicotine with a purity of more than 99%; the collected organic solvent can be reused in the extraction process after being recovered by rectification;

[0041] Step five, the mixed residue obtained in step one is directly subjected to saponification treatment by using an alkali solution II (NaOH, KOH or Ca(OH)2) with a pH value of 10-12, the water content in the mixed residue after saponification treatment is maintained at 80-150%, and then the mixed residue is heated and extracted 2-3 times by using an organic solvent II with a mass of 8-10 times the mass of the mixed residue, the extraction time is 2-4 hours each time, and the extraction temperature is 40-60℃; the extraction liquid obtained each time is combined, and the combined extraction liquid is coarsely filtered to obtain filter residue II and filter liquid II; the filter residue II can be used as an organic fertilizer raw material, and the filter liquid II is subjected to reduced pressure recovery of the solvent under the conditions that the concentration temperature is 40-60℃ and the concentration pressure is 1000-5000 Pa to obtain an extract;

[0042] Step six, dissolve the extract in organic solvent III, heat to micro-boiling, prepare a saturated solution, filter while hot, obtain filtrate III, then cool the filtrate III to crystallize at a temperature of 8~12℃ for 24~36 h, filter after crystallization, remove the wax, obtain filtrate IV;

[0043] Step seven, add acid solution II (hydrochloric acid or sulfuric acid) with pH=2~4 to the filtrate IV for extraction, wherein the volume of the acid solution II is 1 / 2~1 of the volume of the filtrate IV, the extraction times are 2~3 times, and the organic phase is obtained by separation; concentrate the organic phase under the conditions of a concentration temperature of 40~60℃ and a concentration pressure of 1000~5000 Pa, and obtain the crude solanesol crude extract;

[0044] Step eight, dissolve the crude solanesol crude extract in organic solvent IV, prepare a saturated solution, then add activated carbon with a mass of 1 / 6~1 / 3 of the mass of the saturated solution for adsorption treatment, and then use membrane molecular cut-off concentration treatment to obtain the crude solanesol extract; wherein the membrane can be microfiltration, ultrafiltration and nanofiltration, and the device can be hollow fiber, roll type, plate and frame or tube type, etc.

[0045] Step nine, crystallize the crude solanesol extract at a temperature of -5℃~-40℃ for 12~24 h, filter, and obtain light yellow solanesol crystals; dissolve the light yellow solanesol crystals in organic solvent V, prepare a saturated solution, and then recrystallize at a temperature of -5℃~-40℃ for 12~24 h to obtain solanesol with a purity of more than 95%.

[0046] It should be noted that the organic solvent II to the organic solvent V is any one or several of n-hexane, chloroform, ethyl acetate, ethanol, methanol, acetone, and No. 6 solvent oil. The organic solvent II to the organic solvent V can be the same or different, and can be adjusted according to the actual situation.

[0047] Preferably, the whole preparation process also has a reutilization process of residual raw materials, solvents and water, etc., such as the tobacco residues after extracting nicotine and solanesol can be used as raw materials for bio-organic fertilizer; the organic solvents used for extraction / dissolution can also be recycled as solvents after being recovered by rectification.

[0048] The application will be further described in combination with specific examples, but the protection scope of the application is not limited thereto.

[0049] Example 1

[0050] A method for step-by-step extraction of high-purity nicotine and high-purity solanesol from waste tobacco raw materials, please refer to Figure 1 , mainly includes the following steps:

[0051] Step one, waste tobacco is crushed to 20 mesh, then 8 times the mass of water is added to the waste tobacco at a temperature of 40℃ and extracted for 2 times, each time for 2 hours; the extract obtained in each extraction is combined, and the combined extract is coarsely filtered using a plate and frame filter press combined with a microfiltration membrane to obtain filter residue I and transparent and clear filtrate I, the filtrate I is a nicotine concentrate, the extracted tobacco residue and the filter residue I obtained by coarse filtration are combined to obtain a mixed residue, which is not dried and is used as a raw material for extracting solanesol;

[0052] Step two, the filtrate I is acidified using dilute sulfuric acid with a pH of 1, so that the pH of the system after acidification is ≤5; then the extract is coarsely filtered using a plate and frame filter press combined with a microfiltration membrane to obtain a transparent and clear filtrate, then a reverse osmosis membrane is selected for molecular interception to remove macromolecules such as proteins, as well as water molecules and small organic molecules, to obtain a nicotine salt concentrate with a purity of 40%; the water molecules removed by the membrane interception can be reused as extraction water;

[0053] Step three, the pH value of the nicotine salt concentrate is adjusted to 13 using a KOH solution, then organic solvent n-hexane is added for extraction 2 times, and the organic solvent extract is collected; the volume of the organic solvent is 1 / 2 of the volume of the solution to be extracted;

[0054] Step four, the organic solvent extract is subjected to reduced pressure distillation using a rectification column system, the organic solvent is collected at a pressure of 5000 Pa and a temperature of 60℃, and the nicotine is collected at a pressure of 2000 Pa and a temperature of 150℃, to obtain high-purity nicotine with a purity of 99.5%;

[0055] Step five, the mixed residue obtained in step one is subjected to saponification treatment using a KOH solution with a pH of 12, and the water content of the mixed residue after saponification treatment is maintained at 80-150%, then 8 times the amount of methanol is added for extraction, each extraction time is 4 hours, the extraction temperature is 40℃, and the extraction is performed 3 times. The extract obtained in each extraction is combined, and the combined extract is coarsely filtered to obtain filter residue II and filtrate II, the filter residue II can be used as an organic fertilizer raw material, and the filtrate II is subjected to solvent recovery at a temperature of 60℃ and a concentration pressure of 5000 Pa to obtain an extract;

[0056] Step six, the extract is dissolved in ethyl acetate, heated to micro-boiling, prepared into a saturated solution, filtered while hot to obtain filtrate III, then the filtrate III is cooled to crystallize at a temperature of 12℃ for 36 hours to remove wax. After crystallization, filtration is performed to obtain filtrate IV;

[0057] Step seven, 1 times volume of sulfuric acid solution with pH 4 is added to the filtrate IV for extraction, the extraction is 3 times, the organic phase is obtained by liquid separation; the organic phase is recovered under the conditions of temperature 60 DEG C and concentrated pressure 5000 Pa, and the crude solanesol crude extract is obtained;

[0058] Step eight, the crude solanesol crude extract is dissolved with acetone to form a saturated solution, then 1 / 6 of the mass of the saturated solution of activated carbon is added for decolorization and adsorption treatment, and then the membrane molecular cut-off treatment is used, and the solanesol extract is obtained;

[0059] Step nine, the crude solanesol solution is crystallized at low temperature-40 DEG C for 12 h, and then filtered to obtain light yellow solanesol crystals; the solanesol crystals are dissolved with n-hexane to form a saturated solution, and then recrystallized at-5 DEG C for 24 h to obtain solanesol with a purity of 95.2%.

[0060] Example 2

[0061] A method for step-by-step extraction of high-purity nicotine and high-purity solanesol from waste tobacco raw materials, mainly comprising the following steps:

[0062] Step one, the waste tobacco is crushed to 10 mesh, and then 6 times of water by mass of the waste tobacco is added under the heating condition of temperature 60 DEG C for extraction 3 times, and the extraction time is 4 h each time; the extraction liquids obtained by each extraction are combined, and the combined extraction liquid is coarsely filtered by using a plate and frame filter press combined with a microfiltration membrane to obtain filter residue I and transparent and clear filtrate I; the filtrate I is nicotine concentrate liquid; the extraction residue and the filter residue I obtained by coarse filtration are combined to obtain a mixed residue, and the mixed residue is not dried and is reserved as a solanesol extraction raw material;

[0063] Step two, the filtrate I is acidified by using dilute hydrochloric acid with pH 3 to make the pH of the acidified system less than or equal to 5; then the extraction liquid is coarsely filtered by using a plate and frame filter press combined with a microfiltration membrane to obtain transparent and clear filtrate, and then the membrane microfiltration, ultrafiltration, nanofiltration or reverse osmosis membrane is selected to remove macromolecules such as proteins, and water molecules and small organic molecules to obtain nicotine salt concentrate liquid with a purity of 45%; the water molecules removed by the membrane cut-off can be reused as extraction water.

[0064] Step three, the pH value of the nicotine salt concentrate liquid is adjusted to 11 by using a NaOH solution, and then 3 times of chloroform as an organic solvent is added for extraction, the volume of the organic solvent is 1 / 3 of the volume of the solution to be extracted, and the organic solvent extraction liquid is collected;

[0065] Step four, the organic solvent extraction liquid is distilled under reduced pressure by using rectification column system, the organic solvent is collected under the condition of 5000 Pa pressure and 40 DEG C temperature, and the nicotine is collected under the condition of 2000 Pa pressure and 150 DEG C temperature, so high-purity nicotine with 99.5% purity is obtained.

[0066] Step five, the mixed residue obtained in step one is subjected to saponification treatment by using KOH solution with pH value of 10, the moisture content of the mixed residue after saponification treatment is kept between 80-150%, then 6 times of ethyl acetate-ethanol (volume ratio 1:1) mixed solvent is added for extraction, the extraction time is 2 h, the extraction temperature is 60 DEG C, and the extraction times is 2 times, the extraction liquid obtained in each time is combined, the combined extraction liquid is subjected to rough filtration, so filter residue II and filtrate II are obtained, the filter residue II can be used as organic fertilizer raw material, and the filtrate II is subjected to solvent recovery under the condition of 40 DEG C temperature and 1000 Pa concentration pressure, so paste is obtained;

[0067] Step six, the extract is dissolved in n-hexane, heated to micro-boiling, prepared into saturated solution, filtered while hot, so filtrate III is obtained, then the filtrate III is cooled and crystallized at 8 DEG C temperature for 24 h to remove wax, after crystallization, filtration is carried out, so filtrate IV is obtained;

[0068] Step seven, 1 / 2 times of hydrochloric acid solution with pH value of 2 is added to the filtrate IV for extraction, the extraction times is 3 times, so n-hexane phase is obtained, the n-hexane phase is subjected to n-hexane recovery under the condition of 40 DEG C concentration temperature and 1000 Pa concentration pressure, so crude solanesol crude extract is obtained;

[0069] Step eight, the crude solanesol crude extract is dissolved in n-hexane, prepared into saturated solution, then 1 / 3 times of activated carbon of the mass of the saturated solution is added for decolorization adsorption treatment, then membrane molecular cut-off concentration treatment is carried out, so solanesol crude extract is obtained;

[0070] Step nine, the crude solanesol solution is placed in a frozen temperature of-5 DEG C for crystallization for 24 h, filtration is carried out, so light yellow solanesol crystal is obtained, the solanesol crystal is dissolved by heating with acetone, prepared into saturated solution, then crystallization is carried out under the condition of-40 DEG C for 12 h, so solanesol with 95.5% purity is obtained.

[0071] The above only is the preferred embodiment of the present application, and does not limit the present application in any form. Any equivalent transformation or modification according to the essence of the present application should be covered in the protection scope of the present application.

Claims

1. A process for the stepwise extraction of high purity nicotine and high purity solanesol from waste tobacco secondary material, characterized in that, Mainly includes the following steps: Step one, the waste tobacco is crushed, and 6-8 times the mass of water of the waste tobacco is added to the crushed waste tobacco, and the mixture is extracted 2-3 times at a temperature of 40-60 DEG C, and each extraction time is 2-4 h; the extraction liquid obtained each time is combined, and the combined extraction liquid is coarsely filtered to obtain filter residue I and filter liquor I, the filter liquor I is nicotine concentrate, the extraction residue and the filter residue I obtained by coarse filtration are combined to obtain a mixture, and the mixture is the raw material for extracting solanesol; Step two, the filter liquor I is acidified by using an acid solution I with a pH value of 1-3, so that the pH value of the acidified system is less than or equal to 5; then filtering treatment is performed to obtain a nicotine salt concentrate with a purity of 40-45%; Step three, the pH value of the nicotine salt concentrate is adjusted to 11-13 by using an alkali solution I, then 2-3 times of organic solvent I is added for extraction, and the organic solvent extraction liquid is collected; wherein the volume of the organic solvent I is 1 / 3-1 / 2 of the volume of the solution to be extracted; Step four, the organic solvent extraction liquid is subjected to reduced pressure distillation by using a rectification column system, and the organic solvent and nicotine are collected respectively, and the obtained nicotine is high-purity nicotine with a purity of more than 99%; Step five, the mixture obtained in step one is directly subjected to saponification treatment by using an alkali solution II with a pH value of 10-12, then 8-10 times the mass of the mixture of organic solvent II is added for heating extraction 2-3 times, the extraction time of each time is 2-4 h, the extraction temperature is 40-60 DEG C, the extraction liquid obtained each time is combined, and the combined extraction liquid is coarsely filtered to obtain filter residue II and filter liquor II, the filter residue II can be used as an organic fertilizer raw material, and the filter liquor II is subjected to reduced pressure recovery of solvent under the conditions that the concentration temperature is 40-60 DEG C and the concentration pressure is 1000-5000 Pa to obtain an extract; Step six, the extract is dissolved in organic solvent III, heated to micro-boiling, prepared into a saturated solution, filtered while hot to obtain filter liquor III, then the filter liquor III is cooled and crystallized at a temperature of 8-12 DEG C for 24-36 h, filtered after crystallization to remove wax, and filter liquor IV is obtained; Step seven, the filter liquor IV is extracted by adding an acid solution II with a pH value of 2-4, and the extraction is performed 2-3 times to obtain an organic phase; the organic phase is concentrated under the conditions that the concentration temperature is 40-60 DEG C and the concentration pressure is 1000-5000 Pa to obtain a crude solanesol crude extract; Step eight, the crude solanesol crude extract is dissolved in organic solvent IV to prepare a saturated solution, then 1 / 6-1 / 3 of the mass of the saturated solution of activated carbon is added for adsorption treatment, and then the membrane molecular cut-off concentration treatment is performed to obtain a solanesol crude extract; Step nine, the solanesol crude extract is crystallized at a temperature of-5 DEG C to-40 DEG C for 12-24 h, and plate and frame filtration is performed to obtain light yellow solanesol crystals; the light yellow solanesol crystals are dissolved in organic solvent V to prepare a saturated solution, and then recrystallized at a temperature of-5 DEG C to-40 DEG C for 12-24 h to obtain solanesol with a purity of more than 95%.

2. A process for the fractional extraction of high purity nicotine and high purity solanesol from waste tobacco according to claim 1, characterized in that, In step one, the combined extract is coarsely filtered using a plate and frame filter press combined with a microfiltration membrane.

3. A process for the fractional extraction of high purity nicotine and high purity solanesol from waste tobacco according to claim 1, characterized in that, In step two, the acidified system is first coarsely filtered using a plate and frame filter press combined with a microfiltration membrane, and then membrane filtration is performed using a microfiltration membrane, an ultrafiltration membrane, a nanofiltration membrane or a reverse osmosis membrane. The water molecules removed by the membrane cutoff can be reused as extraction water.

4. A process for the fractional extraction of high purity nicotine and high purity solanesol from waste tobacco according to claim 1, characterized in that, In step three, the base solution I is any one or several of KOH, NaOH, Ca(OH)2, ammonia water and Na2CO3.

5. A process for the fractional extraction of high purity nicotine and high purity solanesol from waste tobacco according to claim 1, characterized in that, In step three, the organic solvent I is any one or several of n-hexane, diethyl ether, ethyl acetate, chloroform and petroleum ether.

6. A process for the fractional extraction of high purity nicotine and high purity solanesol from waste tobacco according to claim 1, characterized in that, In step four, the organic solvent extract is reduced pressure distilled using a rectification column system, the organic solvent is collected at 40-60℃, and nicotine is collected at 150-160℃. The collected organic solvent can be reused after being recovered by rectification.

7. A process for the fractional extraction of high purity nicotine and high purity solanesol from waste tobacco according to claim 1, characterized in that, In step five, the base solution II is NaOH, KOH or Ca(OH)2, and the water content of the mixed residue after saponification treatment is maintained at 80-150%.

8. A process for the fractional extraction of high purity nicotine and high purity solanesol from waste tobacco according to claim 1, characterized in that, The organic solvent II to the organic solvent V are any one or several of n-hexane, chloroform, ethyl acetate, ethanol, methanol, acetone and No. 6 solvent oil.

9. A process for the fractional extraction of high purity nicotine and high purity solanesol from waste tobacco according to claim 1, characterized in that, The acid solution I or the acid solution II is hydrochloric acid or sulfuric acid, wherein the volume of the acid solution II is 1 / 2-1 times the volume of the filtrate IV.

10. A process for the fractional extraction of high purity nicotine and high purity solanesol from waste tobacco according to claim 1, characterized in that, In step eight, a microfiltration membrane, an ultrafiltration membrane or a nanofiltration membrane is used for membrane molecular cutoff.

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