A method for comprehensive utilization of waste tobacco with high value

Abstract

The application discloses a new method for high-value comprehensive utilization of waste tobacco, which extracts active substances with high value such as nicotine, solanesol, chlorogenic acid, rutin, tobacco essential oil, tobacco protein and polysaccharide from waste tobacco raw materials. The nicotine with a purity greater than 99%, the solanesol with a purity greater than 95%, the rutin and chlorogenic acid with a purity greater than 98%, the tobacco essential oil and the tobacco plant protein polysaccharide can be prepared. The method effectively solves the problem of high-value comprehensive utilization of waste tobacco, significantly improves the utilization rate of waste tobacco, solves the problems of large energy consumption, many impurities and complex production process in the production process. The method has the advantages of less organic solvent, high product purity, low production cost, simple process route and suitability for large-scale production.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of waste tobacco reutilization, in particular to a high-value comprehensive utilization method of 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 solanesol, nicotine, rutin, chlorogenic acid, tobacco essential oil, tobacco protein and tobacco polysaccharide have wide application in chemical industry, medicine, agriculture and other fields, and have important development and utilization value. Extracting active substances from waste tobacco and developing and utilizing them can not only change waste tobacco into raw materials needed for production, but also effectively reduce environmental pollution, in line with the concept of green development. Solanesol is a long-chain terpene alcohol, and its content in tobacco is about 0.3%-0.8%. Solanesol is also an important pharmaceutical intermediate, an irreplaceable component of ubiquinone drug intermediates, and a natural raw material that cannot be replaced in the synthesis of vitamin K side chains and coenzyme Q10, as well as in the synthesis of anti-ulcer drugs and anticancer drugs. As a medicinal raw material, the content of solanesol is required to be more than 90%, therefore, preparing solanesol with a purity higher than 90% is the key to the in-depth development and utilization of solanesol. Nicotine, also known as nicotine, is a biological alkaloid with very wide application. Nicotine can produce certain physiological stimulation to humans, thereby producing addiction, which is the main factor that makes tobacco have commodity value. In addition, rutin and chlorogenic acid are also important active substances in tobacco, and have important research and development value. Rutin can be used as an edible antioxidant and a nutritional enhancer, in addition, rutin also has anti-inflammatory effects, maintains vascular resistance, reduces its permeability, reduces fragility, and can be used for the prevention and treatment of cerebral hemorrhage, hypertension, retinal hemorrhage, purpura and acute hemorrhagic nephritis. Chlorogenic acid has a wide range of antibacterial effects, can increase the central excitability of rats, increase the small intestine peristalsis of rats and mice, and increase the uterine tension of rats; has choleretic effect, can increase the bile secretion of rats, etc. In recent years, with the in-depth study of tobacco, the good application value of active substances in tobacco has gradually been recognized and accepted by people. Extracting nicotine, solanesol, rutin, chlorogenic acid, tobacco essential oil, tobacco plant protein and plant polysaccharide and other substances from waste tobacco not only has high economic value, but also brings new opportunities for tobacco-related enterprises and tobacco farmers; at the same time, it also makes certain contribution 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 deep processing products are extracted first, and then the remaining residues are used as raw materials to produce organic fertilizer. This is easy to lead to the waste of other active substances in tobacco, therefore, it is of great significance to improve the comprehensive utilization rate of waste tobacco and prepare more active substances with high added value.

[0004] Patent with publication number CN104086425 studies a method for simultaneously extracting chlorogenic acid, solanesol, nicotine and rutin. The method is to use ethanol as a solvent to simultaneously extract the above four substances, and then to achieve separation by steps. The obtained nicotine is nicotine sulfate with a purity of 40%, and the obtained solanesol is a crude product. If further purification is needed, column chromatography is needed. Patent with publication number CN103342628 discloses a method for simultaneously extracting nicotine and solanesol, which uses alkaline ethanol to simultaneously extract nicotine and solanesol, and then acidifies and extracts to separate nicotine and solanesol. Patent with publication number CN114534361A discloses a method for simultaneously extracting tobacco essential oil, nicotine and extract, but the purity of the obtained products is not high, which is inconsistent with the method used in the present application.

[0005] Therefore, the current development and utilization of waste tobacco still has the problems of insufficient comprehensive utilization value of high-value waste tobacco, serious resource waste, complex production process, low product purity, excessive energy consumption and the like. SUMMARY

[0006] In order to solve the problems in the prior art, the present application provides a method for comprehensive utilization of high-value waste tobacco, which simultaneously extracts active substances with high application value such as nicotine, solanesol, chlorogenic acid, rutin, tobacco essential oil, tobacco plant protein and plant polysaccharide from waste tobacco raw materials, effectively solves the problem of comprehensive utilization of high-value waste tobacco, and improves the utilization rate of waste tobacco. The method has the advantages of less organic solvent consumption, high product purity, low production cost, simple process route, and is suitable for large-scale production.

[0007] In order to achieve the above-mentioned purposes, the specific scheme adopted by the present application is as follows:

[0008] A method for comprehensive utilization of high-value waste tobacco, comprising the following steps:

[0009] Step one, waste tobacco is crushed to 10-20 mesh, then 10-14 times the mass of the waste tobacco of alkali solution I is added, and extraction is carried out at a temperature of 40-60℃ for 2-4 h; then water vapor is introduced for distillation, the obtained distillate is absorbed with acid solution I with a pH of 1-3, until the pH of the absorption liquid is ≤5, to obtain a nicotine salt solution;

[0010] Step two, 1 / 3-1 / 2 volume of organic solvent I is added to the nicotine salt solution and extracted 2-3 times, and the liquid is separated to obtain water phase I and organic phase I. After the organic phase I is dried with anhydrous sodium sulfate to recover the solvent, tobacco essential oil is obtained; the water phase I is filtered to obtain a nicotine salt concentrate with a purity of 40-45%;

[0011] Step three, adjust the pH value of the nicotine salt concentrated solution to 11~13 with the alkaline solution II, then extract 2~3 times with the organic solvent II, and collect the organic solvent extract; wherein the volume of the organic solvent II is 1 / 3~1 / 2 of the volume of the solution to be extracted;

[0012] Step four, perform vacuum distillation on the organic solvent extract by using a rectification column system, and collect the organic solvent and nicotine respectively; the obtained nicotine is high-purity nicotine with a purity greater than 99%;

[0013] Step five, filter the residue left after the distillation in step one while hot to obtain filter cake I and filtrate I; the filter cake I can be used as raw material for producing organic fertilizer; the filtrate I is adjusted to a pH value of 4 by using hydrochloric acid at a temperature of 60~70℃, then cooled and crystallized for 6~8 hours, filtered to obtain filter cake II and filtrate II; the filter cake II is crude rutin; the crude rutin is dissolved in hot water, filtered while hot, then further recrystallized to obtain rutin with a purity greater than 98%; the filtrate II is subjected to membrane molecular interception to obtain water, concentrated solution, macromolecular polysaccharide and protein macromolecular substance respectively; wherein the macromolecular polysaccharide and protein macromolecular substance can be used as raw material for feed additives, and the water can be recycled;

[0014] Step six, dissolve the concentrated solution obtained by membrane concentration in organic solvent III, heat to 40~50℃, then separate into water phase II and organic phase II; cool and crystallize the organic phase II at a temperature of 8~12℃ for 24~36 hours, then filter to obtain filter cake III and filtrate III; the filter cake III is plant wax, and the filtrate III is a dilute solution of solanesol; the water phase II is adjusted to neutral with sodium carbonate, then concentrated by using a membrane; the concentrate is dissolved by adding a methanol solution with a volume concentration of 60~80%, filtered; the obtained filtrate is a chlorogenic acid extract; the chlorogenic acid extract is concentrated, then enriched by using a macroporous adsorption resin to obtain chlorogenic acid with a purity greater than 98%;

[0015] Step seven, add acid solution II with a pH value of 2~4 and a volume of 1 / 2~1 of the volume of the filtrate III to the filtrate III to perform extraction for 2~3 times, and separate into organic phase III; concentrate the organic phase III under the conditions of a concentration temperature of 40~60℃ and a concentration pressure of 1000~5000 Pa to obtain crude solanesol extract;

[0016] Step eight, dissolve the crude solanesol extract in organic solvent IV to configure a saturated solution, concentrate by using a membrane molecular interception, then add activated carbon with a mass of 1 / 6~1 / 3 of the mass of the saturated solution to perform adsorption treatment to obtain solanesol crude extract;

[0017] Step nine, the crude solanols crude extract is crystallized at a temperature of-5℃ to-40℃ for 12 to 24 hours, filtered, and light yellow solanols crystals are obtained; the light yellow solanols crystals are dissolved in an organic solvent V to prepare a saturated solution, and then recrystallized at a temperature of-5℃ to-40℃ for 12 to 24 hours, so that solanols with a purity of greater than 95% are obtained.

[0018] Further, the acid solution I is hydrochloric acid or sulfuric acid; the alkali solution I is any one or several of KOH, NaOH, CaO, Ca(OH)2, ammonia water, and Na2CO3.

[0019] Further, the water phase I is first coarsely filtered by using a plate and frame filter press combined with a microfiltration membrane, and then membrane filtration treatment is performed by using a microfiltration membrane, an ultrafiltration membrane, a nanofiltration membrane, or a reverse osmosis membrane; water molecules removed by membrane molecular interception can be reused as extraction water.

[0020] Further, the organic solvent I used is any one or several of n-hexane, petroleum ether, diethyl ether, and chloroform.

[0021] Further, the alkali solution II is any one or several of KOH, NaOH, CaO, Ca(OH)2, ammonia water, and Na2CO3.

[0022] The organic solvent II is one or several of n-hexane, ethyl acetate, chloroform, and petroleum ether.

[0023] Further, vacuum distillation is performed on the organic solvent extraction liquid by using a rectification column system, organic solvents are collected at a temperature of 40 to 60℃, nicotine is collected at a temperature of 150 to 160℃, and the collected organic solvents can be reused in the extraction process after being recovered by rectification.

[0024] Further, the organic solvent III is one or several of n-hexane, chloroform, ethyl acetate, ethanol, methanol, acetone, and No. 6 solvent oil.

[0025] Further, the acid solution II is hydrochloric acid or sulfuric acid, and the volume of the acid solution II is 1 / 2 to 1 times the volume of the filtrate III.

[0026] Further, a microfiltration membrane, an ultrafiltration membrane, or a nanofiltration membrane is used for molecular interception of the membrane.

[0027] and / or;

[0028] In step eight, a microfiltration membrane, an ultrafiltration membrane, or a nanofiltration membrane is used for molecular interception of the membrane.

[0029] Further, the organic solvent IV is any one or several of n-hexane, diethyl ether, ethyl acetate, ethanol, methanol, chloroform, acetone, and No. 6 solvent oil.

[0030] and / or;

[0031] The organic solvent V is any one or several of n-hexane, diethyl ether, ethyl acetate, ethanol, methanol, chloroform, acetone, and No. 6 solvent oil.

[0032] Beneficial effects:

[0033] 1) The utilization rate of waste tobacco raw materials is greatly improved: the method simultaneously extracts and separates nicotine, solanesol, chlorogenic acid, rutin, tobacco essential oil, tobacco protein, and polysaccharides and other active substances with high value from waste tobacco raw materials. The problem of raw material waste caused by single extraction of nicotine, solanesol and the like from waste tobacco is solved, and the comprehensive utilization efficiency of waste tobacco raw materials is effectively improved. Rational utilization of tobacco raw materials is achieved, resource waste is reduced, and production costs are saved. According to the processing of 10,000 tons of waste tobacco raw materials per year, more than 100-150 tons of high-purity nicotine with a purity of more than 99% and 30-50 tons of solanesol with a purity of more than 95% can be obtained, 2,000-3,500 tons of plant protein and polysaccharides, 100-120 tons of tobacco essential oil, 10-20 tons of rutin with a purity of more than 98%, and 5-15 tons of chlorogenic acid with a purity of more than 98% are achieved, realizing maximum economic benefits.

[0034] 2) The wide application of membranes significantly reduces energy consumption and simplifies the operation steps: the membrane filtration and concentration process is used in the extraction process to replace the traditional heating evaporation to remove water and concentrate, and the method of removing macromolecular impurities such as proteins and polysaccharides by membrane molecular interception, which greatly reduces the energy consumption in the entire production process. These not only simplify the process, but also will greatly reduce a large part of energy consumption. According to a processing capacity of 10,000 tons of waste tobacco raw materials per year, more than 30 million yuan of energy consumption expenditure can be saved annually; it meets the requirements of national green and low-carbon production. During the purification of nicotine, polysaccharides and proteins and other substances are removed by membrane molecular interception, and then alkali treatment, solvent extraction, and vacuum distillation processes are used, so that most of the emulsified impurities in the system are removed, simplifying the subsequent operation.

[0035] 3) The purity of the product is greatly improved: in the nicotine extraction process, membrane molecular interception is combined with water vapor distillation, organic solvent extraction and other processes to simplify the production process, improve the purity of nicotine, and obtain high-purity nicotine with a purity of more than 99%. In the solanesol extraction process, through solvent extraction, dissolution, activated carbon adsorption, membrane filtration, and crystallization, the purity of solanesol is more than 95%, which fully meets the requirements of solanesol raw materials for pharmaceutical intermediates. In addition, rutin and chlorogenic acid can also reach more than 98%. These greatly improve the utilization value of these active substances and give the products higher added value.

[0036] 4), simple production process, almost no waste in the process: from the production process, using waste tobacco raw materials, while extracting and separating nicotine, solanesol, chlorogenic acid, rutin, tobacco essential oil, tobacco protein and polysaccharide and other active substances with high value, simple preparation process, easy to industrial production. In the production process, the recovered water, organic solvent and other materials can be reused as raw materials, which not only reduces the consumption of raw materials and saves the cost, but also greatly reduces the emission of waste in the production process, has good environmental benefits, and meets the requirements of environmental protection. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 The preparation process flow chart of various active substances in the application. DETAILED DESCRIPTION

[0038] The technical solutions of the application will be described below in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the application, not all. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the application.

[0039] The application provides a waste tobacco high-value comprehensive utilization method, the waste tobacco raw material includes tobacco stems and waste tobacco leaves generated in the tobacco harvesting process, and waste tobacco residues and broken ends generated in the re-drying, preparation of cigarettes and packaging and transportation process which cannot continue to be used as raw materials for cigarette production; the preparation process comprises the following steps:

[0040] The application provides a waste tobacco high-value comprehensive utilization method, please refer to Figure 1 , comprising the following steps:

[0041] Step one, waste tobacco is crushed to 10-20 mesh, then 10-14 times the mass of alkali solution I (any one or several of KOH, NaOH, CaO, Ca(OH)2, ammonia water, Na2CO3) is added, and extraction is carried out at a temperature of 40-60℃ for 2-4 h; then water vapor is introduced for distillation, the obtained distillate is absorbed with acid solution I (hydrochloric acid or sulfuric acid) with pH of 1-3, until the pH of the absorption solution is ≤5, and nicotine salt solution is obtained;

[0042] Step two, add organic solvent I (any one or several of n-hexane, petroleum ether, diethyl ether, chloroform) with a volume of 1 / 3~1 / 2 of the volume of the nicotine salt solution to the nicotine salt solution, extract 2~3 times, separate the liquid, obtain aqueous phase I and organic phase I, dry the organic phase I with anhydrous sodium sulfate, recover the solvent to obtain tobacco essential oil; first use a plate and frame filter press combined with a microfiltration membrane to perform rough filtration on the aqueous phase I, and then use a microfiltration membrane, an ultrafiltration membrane, a nanofiltration membrane, or a reverse osmosis membrane to perform membrane filtration treatment; the water molecules removed by the membrane cutoff can be reused as extraction water;

[0043] Step three, adjust the pH value of the nicotine salt concentrated solution to 11~13 with an alkaline solution II (any one or several of KOH, NaOH, CaO, Ca(OH)2, ammonia water, Na2CO3), then add organic solvent II (one or several of n-hexane, ethyl acetate, chloroform, petroleum ether) to extract 2~3 times, and collect the organic solvent extract; the volume of the organic solvent II is 1 / 3~1 / 2 of the volume of the solution to be extracted;

[0044] Step four, use a rectification column system to perform vacuum distillation on the organic solvent extract, collect the organic solvent at 40~60℃, and collect the nicotine at 150~160℃; the obtained nicotine is high-purity nicotine with a purity greater than 99%; the collected organic solvent can be reused in the extraction process after being recovered by rectification;

[0045] Step five, filter the residue left after distillation in step one while it is hot to obtain filter cake I and filtrate I; the filter cake I can be used as a raw material for producing organic fertilizer; adjust the pH value of the filtrate I to 4 using hydrochloric acid at a temperature of 60~70℃, then cool and crystallize for 6~8 h, filter to obtain filter cake II and filtrate II; the filter cake II is crude rutin; dissolve the crude rutin with hot water, filter while it is hot, then further recrystallize to obtain rutin with a purity greater than 98%; use membrane molecular cutoff to obtain water, concentrated solution, macromolecular polysaccharides, and protein macromolecular substances from the filtrate II; the macromolecular polysaccharides and protein macromolecular substances can be used as raw materials for feed additives, and the water can be recycled;

[0046] Step six, the concentrated solution obtained by concentrating the membrane is dissolved in organic solvent III (one or more of n-hexane, chloroform, ethyl acetate, ethanol, methanol, acetone, No. 6 solvent oil) with a volume of 3-4 times of the concentrated solution, heated to 40-50 DEG C, and then separated into an aqueous phase II and an organic phase II, the organic phase II is cooled to crystallize at a temperature of 8-12 DEG C for 24-36 h, then filtered to obtain a filter cake III and a filtrate III, the filter cake III is a plant wax, and the filtrate III is a dilute solution of solanesol; the aqueous phase II is neutralized with sodium carbonate, then concentrated by a membrane, the concentrate is dissolved by adding a 60-80% concentration methanol solution, filtered, and the obtained filtrate is a chlorogenic acid extract, which is enriched by a macroporous adsorption resin after concentration, to obtain chlorogenic acid with a purity of more than 98%;

[0047] Step seven, an acid solution II (hydrochloric acid or sulfuric acid) with a pH of 2-4 and a volume of 1 / 2-1 times of the filtrate III is added to the filtrate III for extraction, the extraction is performed 2-3 times, and the organic phase III is obtained by separation; the organic phase III is concentrated under the conditions of a concentration temperature of 40-60 DEG C and a concentration pressure of 1000-5000 Pa, to obtain a crude solanesol extract;

[0048] Step eight, the crude solanesol extract is dissolved in an organic solvent IV to prepare a saturated solution, which is treated by a membrane molecular cut-off, and then activated carbon with a mass of 1 / 6-1 / 3 of the saturated solution is added for adsorption treatment, to obtain a crude solanesol extract;

[0049] Step nine, the crude solanesol extract is crystallized at a temperature of-5 DEG C to-40 DEG C for 12-24 h, filtered, and a light yellow solanesol crystal is obtained; the light yellow solanesol crystal is dissolved in an organic solvent V to prepare a saturated solution, which is 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%.

[0050] It should be noted that in steps five and eight, a microfiltration membrane, an ultrafiltration membrane or a nanofiltration membrane is used for membrane molecular cut-off;

[0051] In steps eight and nine, the organic solvent IV and the organic solvent V are any one or more of n-hexane, diethyl ether, ethyl acetate, ethanol, methanol, chloroform, acetone and No. 6 solvent oil.

[0052] The application is further described below in combination with specific examples, but the protection scope of the application is not limited thereto.

[0053] Example 1

[0054] A high-value comprehensive utilization method of waste tobacco mainly includes the following steps:

[0055] Step one, waste tobacco is crushed to 20 mesh, then 10 times of waste tobacco is added into dilute KOH solution to extract under the condition of 40℃ for 2 hours; then water vapor is introduced to distill, and the distillate is absorbed by dilute hydrochloric acid with pH value of 3 until the pH value of the absorption solution is less than or equal to 5, to obtain nicotine salt solution;

[0056] Step two, the nicotine salt solution is extracted twice by adding 1 / 2 volume of n-hexane, and then separated to obtain water phase I and organic phase I; the organic phase I is dried by anhydrous sodium sulfate and the solvent is recovered to obtain tobacco essential oil; the water phase I is treated by reverse osmosis membrane to remove water molecules and small molecular organic impurities, to obtain nicotine salt concentrate with purity of 40%.

[0057] Step three, the pH value of the nicotine salt concentrate is adjusted to 13 by NaOH solution, then petroleum ether is added to extract 3 times, and the organic solvent extraction solution is collected; the volume of the organic solvent is 1 / 3 of the volume of the solution to be extracted.

[0058] Step four, the organic solvent extraction solution is subjected to reduced pressure distillation by using rectification column system, and the organic solvent is collected under the condition of 5000 Pa pressure and 400℃ temperature; the nicotine is collected under the condition of 2000 Pa pressure and 150℃ temperature, to obtain high-purity nicotine with purity of 99.5%.

[0059] Step five, the residue left after distillation in step one is filtered while hot to obtain filter cake I and filtrate I; the filter cake I can be used as raw material for producing organic fertilizer; the pH value of the filtrate I is adjusted to 4 by using hydrochloric acid at 60℃, then cooled and crystallized for 6 hours, filtered to obtain filter cake II and filtrate II; the filter cake II is crude rutin; the crude rutin is dissolved in hot water, filtered while hot, then further recrystallized to obtain rutin with purity of more than 98%; the filtrate II is treated by membrane molecular cut-off to obtain water, concentrate, macromolecular polysaccharide and protein macromolecular substance; the macromolecular polysaccharide and protein macromolecular substance can be used as raw material for feed additive, and the water can be recycled.

[0060] Step six, the concentrate obtained by membrane concentration is dissolved in ethyl acetate, heated to 40℃, then separated to obtain water phase II and organic phase II; the organic phase II is cooled and crystallized at 12℃ for 36 hours; after crystallization, the filter cake III and filtrate III are obtained by filtration; the filter cake III is plant wax, and the filtrate III is solanols dilute solution; the water phase II is adjusted to neutral by sodium carbonate, then concentrated by membrane, and the concentrate is dissolved by adding 60% methanol solution and filtering, to obtain chlorogenic acid extract; the chlorogenic acid extract is concentrated, then enriched by using macroporous adsorption resin, to obtain chlorogenic acid with purity of more than 98%.

[0061] Step seven, the filtrate III is extracted with 1 volume of hydrochloric acid solution with pH 4 again, the extraction is performed for 2 times, and an organic phase III is obtained by separation; the organic phase III is concentrated at a concentration temperature of 40℃ and a concentration pressure of 1000 Pa, and a crude solanesol extract is obtained;

[0062] Step eight, the crude solanesol extract is dissolved in n-hexane to form a saturated solution, the saturated solution is treated by a microfiltration membrane with a molecular cut-off, then 1 / 6 of the mass of activated carbon of the saturated solution is added to the saturated solution for adsorption treatment, and a solanesol crude extract is obtained;

[0063] Step nine, the solanesol crude extract is crystallized at low temperature of -40℃ for 12 hours, and filtered to obtain light yellow solanesol crystals; the solanesol crystals are dissolved in n-hexane by heating, and a saturated solution is formed; the saturated solution is recrystallized at a temperature of -5℃ for 24 hours, and solanesol with a purity of 95.2% is obtained.

[0064] Example 2

[0065] A method for comprehensive utilization of waste tobacco with high value mainly comprises the following steps:

[0066] Step one, waste tobacco is crushed to 10 mesh, then 14 times of the mass of the waste tobacco of dilute NaOH solution is added to extract under the condition of heating at a temperature of 60℃, and the extraction time is 4 hours; then water vapor is introduced for distillation, and the distillate is absorbed by dilute sulfuric acid solution with pH 1 until the pH of the absorption solution is less than or equal to 5, and a nicotine salt solution is obtained;

[0067] Step two, 1 / 2 volume of petroleum ether is added to the nicotine salt solution for extraction for 3 times, and the liquid is separated to obtain water phase I and organic phase I; after the organic phase I is dried by anhydrous sodium sulfate, the solvent is recovered, and tobacco essential oil is obtained; the water phase I is subjected to molecular cut-off by membrane microfiltration to remove water molecules and small molecules of organic matter and other impurities with small molecular weight, and a nicotine salt concentrated solution with a purity of 45% is obtained;

[0068] Step three, the pH value of the nicotine salt concentrated solution is adjusted to 11 by KOH solution, then chloroform is added for extraction for 2 times, the volume of the organic solvent is 1 / 2 of the volume of the solution to be extracted, and the organic solvent extraction liquid is collected;

[0069] Step four, the organic solvent extraction liquid is subjected to vacuum distillation by using a rectification column system, the organic solvent is collected at a pressure of 5000 Pa and a temperature of 60℃, and nicotine is collected at a pressure of 2000 Pa and a temperature of 160℃, and nicotine with a purity of 99.5% is obtained;

[0070] Step five, the residue left after step one distillation is filtered while hot to obtain filter cake I and filtrate I, the filter cake I can be used as raw material for producing organic fertilizer, the pH value of the filtrate I is adjusted to 4 at 70 DEG C using hydrochloric acid, then it is cooled and crystallized for 8 hours to obtain filter cake II and filtrate II, the filter cake II is crude rutin, the crude rutin is dissolved with hot water, filtered while hot, then further recrystallized to obtain rutin with purity greater than 98%; the filtrate II is subjected to ultrafiltration membrane molecular interception to obtain water, concentrated solution, macromolecular polysaccharide and protein macromolecular substance respectively; the macromolecular polysaccharide and protein macromolecular substance can be used as raw material for feed additive, and the water can be recycled;

[0071] Step six, the concentrated solution obtained by membrane concentration is dissolved with 3 times volume of chloroform at 50 DEG C, then separated to obtain water phase II and organic phase II, the organic phase II is cooled and crystallized at 8 DEG C for 24 hours, then filtered to obtain filter cake III and filtrate III, the filter cake III is plant wax, and the filtrate III is a dilute solution of solanesol; the water phase II is adjusted to neutral with sodium carbonate, then concentrated by membrane, the concentrate is dissolved by adding 80% methanol solution, and filtered to obtain chlorogenic acid extract, the chlorogenic acid extract is concentrated, then enriched by macroporous adsorption resin to obtain chlorogenic acid with purity greater than 98%;

[0072] Step seven, 1 / 2 times volume of sulfuric acid solution with pH=2 is added to the filtrate III for extraction, the extraction is performed for 3 times to obtain organic phase III; the organic phase III is concentrated at a concentration temperature of 60 DEG C and a concentration pressure of 5000 Pa to obtain crude solanesol extract;

[0073] Step eight, the crude solanesol extract is dissolved with ethyl acetate to prepare a saturated solution, the saturated solution is concentrated by microfiltration membrane molecular interception, then 1 / 3 of the mass of the saturated solution is added to the concentrated solution to perform adsorption treatment to obtain solanesol crude extract;

[0074] Step nine, the solanesol crude extract is crystallized at a freezing temperature of-5 DEG C for 24 hours, then filtered to obtain light yellow solanesol crystal; the solanesol crystal is dissolved with acetone, then a saturated solution is prepared, and the saturated solution is crystallized at-40 DEG C for 12 hours to obtain solanesol with purity of 95.5%.

[0075] The above only describes preferred embodiments of the present application and is not intended to limit the present application in any form. Any equivalent transformation or modification according to the essence of the present application should be covered within the protection scope of the present application.

Claims

1. A method for comprehensive utilization of waste tobacco by-products, characterized in that, The method comprises the following steps: Step one, waste tobacco is crushed into 10-20 mesh, then 10-14 times of alkali solution I is added, extraction is carried out at 40-60℃ for 2-4 hours, then water vapor is introduced for distillation, the obtained distillate is absorbed by acid solution I with pH 1-3 until the pH of the absorption solution is less than or equal to 5, and a nicotine salt solution is obtained; Step two, 1 / 3-1 / 2 volume of organic solvent I is added to the nicotine salt solution and extracted for 2-3 times, and the water phase I and the organic phase I are obtained by separation, the organic phase I is dried by anhydrous sodium sulfate to recover the solvent, and then the tobacco essential oil is obtained; the water phase I is filtered to obtain a nicotine salt concentrated solution with a purity of 40-45%; Step three, the pH value of the nicotine salt concentrated solution is adjusted to 11-13 by alkali solution II, then 2-3 times of organic solvent II is added for extraction, and the organic solvent extraction liquid is collected; the volume of the organic solvent II 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 residue left after the distillation in step one is filtered while hot to obtain filter cake I and filtrate I, the filter cake I can be used as a raw material for producing organic fertilizer, the pH value of the filtrate I is adjusted to 4 by using hydrochloric acid at a temperature of 60-70℃, then the filtrate I is cooled and crystallized for 6-8 hours, filtered to obtain filter cake II and filtrate II, the filter cake II is crude rutin, the crude rutin is dissolved in hot water, filtered while hot, then further recrystallized to obtain rutin with a purity of more than 98%; the filtrate II is subjected to membrane molecular interception to obtain water, concentrated solution, macromolecular polysaccharide and protein macromolecular substance respectively; the macromolecular polysaccharide and protein macromolecular substance can be used as a raw material for feed additives, and the water can be recycled; Step six, the concentrated solution obtained by membrane concentration is dissolved in organic solvent III, heated to 40-50℃, then separated to obtain water phase II and organic phase II, the organic phase II is cooled and crystallized at a temperature of 8-12℃ for 24-36 hours, then filtered to obtain filter cake III and filtrate III, the filter cake III is plant wax, and the filtrate III is a dilute solution of solanesol; the water phase II is adjusted to neutral by using sodium carbonate, then concentrated by using a membrane, the concentrate is dissolved by adding a 60-80% methanol solution, filtered, and the obtained filtrate is a chlorogenic acid extraction liquid, the chlorogenic acid extraction liquid is concentrated, then enriched by using a macroporous adsorption resin to obtain chlorogenic acid with a purity of more than 98%; Step seven, acid solution II with pH 2-4 and 1 / 2-1 volume of the filtrate III is added to the filtrate III for extraction, the extraction is carried out for 2-3 times, and the organic phase III is obtained by separation; the organic phase III 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 extract. Step eight, dissolve the solubles of solanesol in organic solvent IV, and prepare a saturated solution, then concentrate the solution by membrane molecular cut-off, and then add active carbon with a mass of 1 / 6~1 / 3 of the saturated solution to adsorb, to obtain the crude extract of solanesol; Step nine, crystallize the crude extract of solanesol at a temperature of-5℃~-40℃ for 12~24 h, and then filter by plate and frame filter to obtain light yellow solanesol crystals; dissolve the light yellow solanesol crystals in organic solvent V, and 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%.

2. The method according to claim 1, wherein the waste tobacco is waste tobacco stems. In step one, the acid solution I is hydrochloric acid or sulfuric acid; and the alkali solution I is any one or several of KOH, NaOH, Ca(OH)2, ammonia water and Na2CO3.

3. The method according to claim 1, wherein the waste tobacco is waste tobacco stem. In step two, first, use a plate and frame filter combined with a microfiltration membrane to coarsely filter the water phase I, and then use a microfiltration membrane, an ultrafiltration membrane, a nanofiltration membrane or a reverse osmosis membrane to perform membrane filtration treatment; the water molecules removed by membrane cut-off can be reused as extraction water.

4. The method according to claim 1, wherein the waste tobacco is waste tobacco stem. In step two, the organic solvent I used is any one or several of n-hexane, petroleum ether, diethyl ether and chloroform.

5. The method according to claim 1, wherein the waste tobacco is waste tobacco stem. In step three, the alkali solution II is any one or several of KOH, NaOH, Ca(OH)2, ammonia water and Na2CO3. The organic solvent II is one or several of n-hexane, ethyl acetate, chloroform and petroleum ether.

6. The method according to claim 1, wherein the waste tobacco is waste tobacco stem. In step four, use a rectification column system to perform vacuum distillation on the organic solvent extraction liquid, collect the organic solvent at 40~60℃, and collect the nicotine at 150~160℃; the collected organic solvent can be reused in the extraction process after being recovered by rectification.

7. The method according to claim 1, wherein the waste tobacco is waste tobacco stem. In step six, the organic solvent III is one or several of n-hexane, chloroform, ethyl acetate, ethanol, methanol, acetone and No. 6 solvent oil.

8. The method according to claim 1, wherein the waste tobacco is waste tobacco stem. In step seven, the acid solution II is hydrochloric acid or sulfuric acid; the volume of the acid solution II is 1 / 2~1 of the volume of the filtrate III.

9. The method according to claim 1, wherein the waste tobacco is waste tobacco stem. In step five, the microfiltration membrane, the ultrafiltration membrane or the nanofiltration membrane is used for membrane molecular cut-off. ​ and / or In step eight, the microfiltration membrane, the ultrafiltration membrane or the nanofiltration membrane is used for membrane molecular cut-off.

10. The method according to claim 1, wherein the waste tobacco is waste tobacco stem. The organic solvent IV is any one or several of n-hexane, diethyl ether, ethyl acetate, ethanol, methanol, chloroform, acetone and No. 6 solvent oil. and / or The organic solvent V is any one or several of n-hexane, diethyl ether, ethyl acetate, ethanol, methanol, chloroform, acetone and No. 6 solvent oil.

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