Recovery of nicotine from tobacco ripening

Abstract

A method for recovering concentrated nicotine from cured tobacco includes collecting a first aqueous solution comprising moisture released from cured tobacco and comprising nicotine. The first aqueous solution is passed through a strong cation resin to sorb the nicotine. A second aqueous solution comprising ammonium hydroxide is passed through the resin to elute the nicotine and form a third aqueous solution comprising nicotine and ammonium hydroxide. The ammonium hydroxide is removed from the third aqueous solution to generate a fourth aqueous solution comprising nicotine. The fourth aqueous solution is incubated under conditions to cause the fourth aqueous solution to separate into a fifth aqueous solution comprising a first nicotine concentration and a sixth aqueous solution comprising a second nicotine concentration. The first nicotine concentration is greater than the second nicotine concentration.

Description

[0001] The present disclosure relates to methods and systems for recovering nicotine from a tobacco curing process.

[0002] Systems for collecting condensate liquid from a tobacco curing barn are known. Additionally, methods for extracting nicotine from the condensate liquid are known. However, such methods tend to result in low nicotine concentrations. Additionally, such methods can result in significant waste, which can include waste that can be difficult to dispose of in an environmentally friendly manner due to its chemical composition.

[0003] The present invention relates to methods and systems that provide high concentration nicotine recovery. The methods and systems can result in little or no waste. The primary byproducts of the methods can include water and fertilizer.

[0004] According to aspects of the invention, a method for recovering concentrated nicotine from tobacco curing is provided. The method includes collecting a first aqueous solution comprising moisture released from curing tobacco, wherein the first aqueous solution comprises nicotine; passing the first aqueous solution through a strong cation resin to sorb the nicotine; passing a second aqueous solution comprising ammonium hydroxide through the resin with the sorbed nicotine to elute the nicotine from the resin and form a third aqueous solution comprising nicotine and ammonium hydroxide; removing the ammonium hydroxide from the third aqueous solution to produce a fourth aqueous solution comprising nicotine; incubating the fourth aqueous solution at a temperature between 60 degrees Celsius and 210 degrees Celsius to cause the fourth aqueous solution to separate into a fifth aqueous solution comprising a first nicotine concentration and a sixth aqueous solution comprising a second nicotine concentration, wherein the first nicotine concentration is greater than the second nicotine concentration; and collecting the fifth aqueous solution to recover concentrated nicotine.

[0005] The recovered nicotine can have a relatively high concentration. For example, the fifth aqueous solution can comprise nicotine at a concentration of 70% by weight or greater, such as 75% by weight or greater. Such concentrations can be substantially higher than concentrations obtained with previous methods of recovering nicotine from a tobacco curing process.

[0006] The method can also include passing a seventh aqueous solution comprising nitric acid through the resin to regenerate the resin and elute the ammonium hydroxide and produce an eighth aqueous solution comprising NH4NO3 (ammonium nitrate), which can be used as a fertilizer. Excess ammonium hydroxide can be removed by a stripping process. The removed ammonium hydroxide or ammonia can be reacted with excess nitric acid to produce additional ammonium nitrate. There is little to no waste. Water and ammonium nitrate, which can be used as a fertilizer, can be the primary byproducts accompanying nicotine recovery.

[0007] According to aspects of the present disclosure, a system for recovering concentrated nicotine from tobacco curing is provided. The system includes a source of an aqueous solution comprising condensed moisture released from tobacco during curing, wherein the condensed moisture comprises nicotine. The system includes an ion exchange column comprising a strong cation resin through which the aqueous solution comprising condensed moisture is passed to sorb the nicotine. The system includes a first pump operably coupled to a source of an aqueous ammonium hydroxide solution and the ion exchange column and configured to pump the aqueous ammonium hydroxide solution through the strong cation resin to elute the nicotine from the resin. The system includes a stripping device configured to receive the aqueous solution comprising nicotine and ammonium hydroxide that has passed through the resin, wherein the stripping device is operably coupled to a source of a gas, wherein the stripping device and the gas are configured to remove ammonia evolved from the ammonium hydroxide in the aqueous solution comprising nicotine and ammonium hydroxide, wherein the ammonia is carried away in a gas stream. The system includes a thermostatic settler operably coupled to the stripping device and configured to receive the aqueous solution exiting the stripping device, wherein the aqueous solution exiting the stripping device comprises the eluted nicotine from the ion exchange column that has had the ammonium hydroxide removed therefrom in the stripping device, wherein the thermostatic settler is configured to incubate the aqueous solution comprising the eluted nicotine that has had the ammonium hydroxide removed therefrom at a temperature between 60 degrees Celsius and 210 degrees Celsius to cause the incubated aqueous solution to separate into an aqueous solution comprising a first nicotine concentration and an aqueous solution comprising a second nicotine concentration, wherein the first nicotine concentration is greater than the second nicotine concentration. The aqueous solution comprising the first nicotine concentration can be collected to recover concentrated nicotine.

[0008] The system can include a condenser operably coupled to the source of the aqueous solution comprising condensed moisture. The condenser can be configured to condense moisture released from the tobacco during the curing process.

[0009] The system can also include a second pump operably coupled to the ion exchange column and a source of an aqueous solution comprising nitric acid. The second pump can be configured to pump the aqueous solution comprising nitric acid through the strong cation resin, wherein the nitric acid elutes the ammonia water from the resin to regenerate the resin. The nitric acid reacts with the ammonium hydroxide to produce an aqueous solution comprising ammonium nitrate. The system can include a valve to direct the flow of the aqueous solution comprising ammonium nitrate to a byproduct tank. The aqueous solution comprising ammonium nitrate can be used as a fertilizer.

[0010] The system and method of the present disclosure includes collecting a first aqueous solution from a tobacco curing process. During curing, tobacco loses a substantial amount of weight. Most of the weight loss is attributed to moisture loss. The moisture can comprise a small percentage of non-water components. For example, the moisture lost from the tobacco during curing can comprise nicotine. Thus, collecting the moisture lost from the tobacco during the curing process can result in the collection of an aqueous solution comprising nicotine.

[0011] The first aqueous solution can be collected during any suitable curing process. For example, the first aqueous solution can be collected during a fire curing process, an air curing process, or a sun curing process. Preferably, the first aqueous solution is collected during a fire curing process.

[0012] In a sun curing process, the tobacco is cured by hanging the leaves outside in the sun until the tobacco is properly dried. For example, the tobacco can be hung outside for about two weeks. Due to the difficulty in controlling conditions in the outside environment and collecting tobacco components released from sun curing, it can be challenging to collect the first aqueous solution during sun curing.

[0013] In an air curing process, the tobacco is hung in a well-ventilated building, such as a well-ventilated barn, to cure. The tobacco can be hung for a period of time, for example, four to eight weeks. Due to the relatively long curing time, the rate of release of tobacco components can be relatively slow during air curing. Collecting the first aqueous solution during air curing can result in a low concentration of tobacco components, such as nicotine, in the aqueous solution.

[0014] In a fire curing process, the tobacco is hung in a closed interior space, such as a tobacco curing barn, and dried with heated air. The heated air can increase the rate of drying of the tobacco and increase the rate of release of tobacco components. Due to the increased rate of release of tobacco components, the first aqueous solution can be more easily collected during fire curing than during other curing processes.

[0015] The first aqueous solution can be collected throughout the curing process or during discrete periods of time during the curing process. Preferably, the first aqueous solution is collected during periods of time when the relative humidity is high due to the release of moisture from the tobacco.

[0016] The tobacco can be heated during curing. In some examples, the air that comes into contact with the tobacco is heated to a temperature in a range of 30 degrees Celsius to 80 degrees Celsius, such as 35 degrees Celsius to 75 degrees Celsius. The temperature can vary during the curing process.

[0017] A system for recovering concentrated nicotine from a tobacco curing process can include components related to the curing of tobacco. For example, the system can include a heater to heat air that comes into contact with the tobacco. The system can include a fan to circulate air that comes into contact with the tobacco. The system can include a heater and a fan.

[0018] The first aqueous solution can be collected in any suitable manner. For example, moisture released from the tobacco during the curing process can be condensed to form the first aqueous solution and collected. A condenser can be used to produce a condensate from the moisture released from the tobacco. Any suitable condenser can be used. The condenser can include a surface that is maintained at a temperature that is lower than the temperature of the environment containing the moisture released from the cured tobacco. The relatively cool temperature of the surface of the condenser will facilitate condensation of the moisture released from the tobacco to form the first aqueous solution. Preferably, the temperature of the surface of the condenser is below the dew point of the atmosphere that the surface of the condenser contacts. In some examples, the temperature of the surface of the condenser is maintained in a range from 1 degrees Celsius to 10 degrees Celsius, such as from 2 degrees Celsius to 5 degrees Celsius.

[0019] The condenser can include a condensing coil. A liquid having a temperature that is lower than the temperature in the environment can be passed through the coil to cool the outer surface of the coil. For example, a refrigerant can be passed through the coil. Moisture released from the tobacco can condense on the coil to form the first aqueous solution.

[0020] The condenser can be located in any suitable location to contact the moisture released from the cured tobacco. The condenser can be placed in the enclosed space in which the tobacco is cured. For example, the condenser can be placed proximate to the ceiling of the tobacco bin. The condenser can be placed in communication with an exhaust vent that exits the enclosed space in which the moisture is released from the cured tobacco. The condenser can be placed in the enclosed space in which the tobacco is cured and proximate to the exhaust vent. The condenser can be placed inside the curing bin or outside the curing bin. One or more condensers can be used to condense the moisture released from the cured tobacco to form the first aqueous solution containing nicotine.

[0021] The first aqueous solution can be collected in any suitable manner. For example, the condenser can include a collection surface below the surface at which the moisture is condensed. The collection surface can collect drips of the first aqueous solution that drip from the surface at which the moisture is condensed. The collection surface can pool the collected first aqueous solution into a conduit. The conduit can transport the first aqueous solution from the collection surface to a collection container for retaining the collected first aqueous solution. The collection container can include a collection tank.

[0022] As one example, a condenser and collection apparatus as described in International Published Patent Application WO 2013 / 180918 can be employed to condense and collect the first aqueous solution.

[0023] The concentration of nicotine in the collected first aqueous solution can vary depending on, for example, the type of cured tobacco and the conditions under which the tobacco is cured. In some examples, the collected first aqueous solution can contain from 100 parts per million nicotine to 500 parts per million nicotine, such as from 200 parts per million nicotine to 400 parts per million nicotine, or 300 parts per million nicotine.

[0024] The collected first aqueous solution comprising nicotine can be passed through a resin to sorb the nicotine. Any suitable resin can be used. Preferably, the resin is a strong cation resin. A strong cation resin is a resin that will attract and retain cations with little or no change in ion exchange capacity over a large pH range, such as pH 2 to pH 12. The strong cation resin can comprise a strong acid functional group. For example, the strong cation resin can comprise a sulfonyl group (-SO3 - ).

[0025] The resin can comprise any suitable polymer. Preferably, the polymer is capable of being functionalised to contain a strong acid moiety. For example, the polymer can be functionalised to comprise a sulfonyl group. In some examples, the resin comprises polystyrene.

[0026] Examples of commercially available strong cation resins that can be used to sorb nicotine from the first aqueous solution are AMBERLITE® IR-120, SR1L Na, IR-122Na and FPC23 H ion exchange resins; TM BC120, BC121 and BC122 ion exchange resins; C 249 ion exchange resin; GC8 ion exchange resin available from ResinTech; and C100 and C100E ion exchange resins.

[0027] Any suitable apparatus can comprise the strong cation resin. Preferably, an ion exchange column comprises the strong cation resin. The column can be packed with the resin and the first aqueous solution can be passed through the column so that nicotine can be sorbed onto the resin. Preferably, the resin in the column has sufficient capacity to sorb all of the nicotine from the first aqueous solution. The sorption capacity of the resin in the column can depend on the degree of functionalisation of the resin (such as the density of sulfonyl groups) and the packing density or amount of resin in the column.

[0028] More than one column can be used to sorb nicotine from the first aqueous solution. When, for example, the cumulative amount of nicotine in the first aqueous solution that has passed through the column approaches or has reached the nicotine sorption capacity of the resin in the column, one or more valves can be used to switch the column through which the first aqueous solution is fed.

[0029] The sorbed nicotine can be eluted from the resin by passing a second aqueous solution comprising ammonium hydroxide through the resin onto which the nicotine is sorbed. The ammonium ions exchange with the nicotine to form a third aqueous solution comprising nicotine and ammonium hydroxide. The nicotine is eluted in its neutral form at a pH of less than 12.

[0030] ​The concentration of ammonium hydroxide in the second aqueous solution and the flow rate of the second aqueous solution through the resin are preferably adapted to result in a nicotine concentration in the third aqueous solution sufficient to cause separation of nicotine into high and low concentrations during a subsequent settling period. Preferably, the concentration of nicotine in the third aqueous solution is 1.3% by weight or more. For example, the concentration of nicotine in the third aqueous solution can be from 2% to 20% by weight. Preferably, the concentration of nicotine in the third aqueous solution is from 10% to 20% by weight.

[0031] The concentration of ammonium hydroxide in the second aqueous solution can be from 2% to 20% by weight, preferably from 5% to 10% by weight. The flow rate of the second aqueous solution through the resin can depend on the concentration of ammonium hydroxide. In some examples, the flow rate of the second aqueous solution through the resin is from 0.1 bed volumes per hour to 3 bed volumes per hour, such as from 0.5 bed volumes per hour to 2 bed volumes per hour. In some examples, the concentration of ammonium hydroxide in the second aqueous solution is from 5% to 10% by weight and the flow rate of the second aqueous solution through the resin is from 0.5 bed volumes per hour to 2 bed volumes per hour.

[0032] Ammonium hydroxide can be removed from the third aqueous solution in any suitable manner to produce a fourth aqueous solution comprising nicotine. Preferably, ammonium hydroxide is removed from the third aqueous solution by an ammonia stripping process. Ammonium hydroxide is in equilibrium with ammonia in water according to the following equation: NH4OH + + OH - <— > H20 + NH3. Thus, removal of ammonia (NH3) from the third aqueous solution will drive the equilibrium towards producing more ammonia and removing ammonium hydroxide from the third aqueous solution.

[0033] Ammonia can be stripped from the third aqueous solution in any suitable manner. For example, the third aqueous solution can be contacted with a stream of gas in which ammonia is soluble. The stream of gas can comprise any suitable gas in which ammonia is soluble. In some examples, the gas is air or nitrogen (N2).

[0034] The stream of gas can be contacted with the third aqueous solution in any suitable manner. For example, the stream of gas can be contacted with the third aqueous solution in a counter-current or cross-current manner.

[0035] For example, the third aqueous solution can be pumped into the top of a stripping column. The stripping column can be packed with a suitable material or object, such as beads. In some examples, the column is packed with Raschig rings. The stream of gas can enter through an opening in the bottom of the column. As droplets of the third aqueous solution fall through the column, the stream of gas can contact the droplets in a counter-current manner and exit through an opening in the top of the column to carry away ammonia.

[0036] The third aqueous solution, the gas stream, or the third aqueous solution and the gas stream can be heated to promote ammonia stripping. Preferably, the third aqueous solution is heated. Preferably, the third aqueous solution is heated prior to introduction into the stripping column. The third aqueous solution can be heated to any suitable temperature. In some examples, the third aqueous solution is heated to a temperature of 20 degrees Celsius to 60 degrees Celsius.

[0037] The solution exiting the stripping column can be recirculated through the stripping column or a subsequent stripping column until the concentration of ammonium hydroxide is sufficiently reduced to produce a fourth aqueous solution comprising nicotine. The fourth aqueous solution can comprise some residual ammonium hydroxide. Preferably, the fourth aqueous solution is free or substantially free of ammonium hydroxide. For example, the concentration of ammonium hydroxide in the fourth aqueous solution can be sufficiently low that the fourth aqueous solution has a pH of 9.5 or less or 9 or less.

[0038] The fourth aqueous solution can then be incubated at a temperature in the range of 60 degrees Celsius to 210 degrees Celsius to cause the fourth aqueous solution to separate into a fifth aqueous solution comprising a first nicotine concentration and a sixth aqueous solution comprising a second nicotine concentration. The first nicotine concentration is greater than the second nicotine concentration. The fourth aqueous solution can be incubated in any suitable manner to cause the separation. For example, the fourth aqueous solution can be introduced into a settler for incubation and separation. The fourth aqueous solution can be introduced into any suitable settler. A suitable settler can be any vessel in which the fourth aqueous solution can be left to stand.

[0039] The temperature within the settler can be controlled in any suitable manner. For example, the settler can comprise a heating element, such as a resistive or inductive heating element, to control the temperature within the settler. The heating element can be in the vessel containing the fourth aqueous solution, outside the vessel containing the fourth aqueous solution, or can be both in and outside the vessel containing the fourth aqueous solution. The temperature of the settler can be controlled with a water jacket surrounding the vessel in which the fourth solution is contained. Heated water can be flowed through the water jacket to control the temperature within the vessel. For the purposes of the present disclosure, a settler in which the temperature can be controlled is a "thermostatic" settler.

[0040] Preferably, the fourth aqueous solution is incubated at a temperature in the range of 60.8 degrees Celsius to 208 degrees Celsius to cause the separation. Preferably, the fourth aqueous solution is incubated at a temperature of less than 100 degrees Celsius. More preferably, the fourth aqueous solution is incubated at a temperature in the range of 80 degrees Celsius to 100 degrees Celsius, such as in the range of 80 degrees Celsius to 90 degrees Celsius.

[0041] The fourth aqueous solution can be incubated at the appropriate temperature for any suitable period of time to allow separation into a fifth aqueous solution comprising a first nicotine concentration and a sixth aqueous solution comprising a second nicotine concentration. For example, the fourth aqueous solution can be incubated for 10 minutes or more. In some examples, the fourth aqueous solution is incubated at the appropriate temperature for a duration of 10 minutes to 120 minutes, such as 10 minutes to 60 minutes or 15 minutes to 30 minutes.

[0042] The system can include more than one settler, such that a second settler can be filled with the fourth aqueous solution while the fourth aqueous solution is incubated in the first settler.

[0043] The first nicotine concentration in the fifth aqueous solution is greater than the nicotine concentration in the fourth aqueous solution, and the second nicotine concentration in the sixth aqueous solution is less than the nicotine concentration in the fourth solution. The first nicotine concentration can be 70% by weight or more, such as 75% by weight or more.

[0044] The fifth aqueous solution can be collected to recover concentrated nicotine from the tobacco curing process. For example, the fifth aqueous solution can be removed from the settler. For example, the fifth aqueous solution can be removed from the bottom of the settler through a stop valve.

[0045] The sixth aqueous solution comprising the second nicotine concentration can be recirculated within the process. For example, the sixth aqueous solution can be added to the vessel in which the first aqueous liquid is stored, can be returned to the settler to be separated again, or can be added to the vessel in which the first aqueous liquid is stored and returned to the settler to be separated again.

[0046] Some water can be evaporated from the sixth aqueous solution to concentrate the nicotine to a similar concentration as the fourth aqueous solution before returning the sixth aqueous solution to the settler. The sixth aqueous solution can be heated to facilitate evaporation and nicotine concentration.

[0047] A seventh aqueous solution comprising nitric acid can be passed through the strong cation resin to regenerate the resin. Regeneration of the resin can allow the resin to be reused, allowing additional collected first aqueous solutions comprising moisture released from the curing tobacco to be processed for nicotine concentration.

[0048] The concentration of nitric acid in the seventh aqueous solution and the flow rate of the seventh aqueous solution through the resin are preferably suitable for completely or nearly completely regenerating the resin. In some examples, the concentration of nitric acid in the seventh aqueous solution is 1 wt% to 10 wt%, such as 5 wt% to 10 wt%, 3 wt% to 7 wt%, or 5 wt%. The flow rate of the seventh aqueous solution through the resin can depend on the concentration of nitric acid. In some examples, the flow rate of the seventh aqueous solution through the resin is 0.1 bed volumes per hour to 3 bed volumes per hour, such as 0.5 bed volumes per hour to 3 bed volumes per hour. In some examples, the concentration of nitric acid in the seventh aqueous solution is 5 wt% to 10 wt% and the flow rate of the seventh aqueous solution through the resin is 0.5 bed volumes per hour to 3 bed volumes per hour.

[0049] When the seventh aqueous solution passes through the resin, the hydronium ions (H + ) present in the seventh aqueous solution due to the nitric acid can exchange with the ammonium ions sorbed to the resin after passing the second aqueous solution through the resin to elute the nicotine. Thus, the resin can be regenerated. When the seventh aqueous solution passes through the resin, the nitric acid can react with the ammonium to produce an eighth aqueous solution comprising ammonium nitrate. The eighth aqueous solution can be stored in a byproduct tank. The eighth aqueous solution can be used as a fertilizer.

[0050] The eighth aqueous solution can comprise excess nitric acid. The eighth aqueous solution comprising excess nitric acid can be contacted with a gas stream comprising stripped ammonia. Contacting the eighth aqueous solution comprising excess nitric acid with a gas comprising ammonia can result in removal of ammonia from the gas stream and production of additional ammonium nitrate.

[0051] After regenerating the column with the seventh aqueous solution, the column can be rinsed with water to remove excess nitric acid from the resin. The resulting aqueous solution can comprise residual nitric acid. This resulting solution can be contacted with a gas stream comprising stripped ammonia.

[0052] The gas stream with removed ammonia can be released to the environment or recycled.

[0053] A system for recovering concentrated nicotine from tobacco curing can comprise any suitable components. The system can comprise a condenser to condense moisture released from the tobacco during curing. The condensed moisture comprises nicotine. The condensed moisture can be a first aqueous solution.

[0054] The system can comprise a collection tank to store the condensed moisture.

[0055] The system can comprise an ion exchange column comprising a strong cation resin. The condensed moisture can be passed through the ion exchange column to sorb the nicotine. The system can comprise a pump operably coupled to the collection tank and the ion exchange column to pump the condensed moisture through the resin.

[0056] The system can include a source of an aqueous solution comprising ammonium hydroxide. The aqueous solution comprising ammonium hydroxide can be the second aqueous solution. The system can include a pump operably coupled to the source of the aqueous solution comprising ammonium hydroxide and the ion exchange column. The pump can be configured to pump the ammonium hydroxide through the resin to elute nicotine from the resin. The solution comprising the eluted nicotine and the ammonium hydroxide can be the third aqueous solution.

[0057] The system can include a stripping device configured to receive the aqueous solution comprising nicotine and ammonium hydroxide that has passed through the resin. The stripping device can be operably coupled to a source of a gas. The stripping device and the gas can be configured to remove ammonia evolved from the ammonium hydroxide in the aqueous solution comprising nicotine and ammonium hydroxide. The ammonia can be carried away in a stream of the gas.

[0058] The stripping device can be configured such that the gas flows in a counter-current fashion or a cross-current fashion relative to the aqueous solution comprising nicotine and ammonium hydroxide. The stripping device can include a column packed with a suitable material or objects, such as beads. In some examples, the column is packed with Raschig rings. In a counter-current stripping device, the stream of gas can enter through an opening in the bottom of the column. As droplets of the third aqueous solution fall through the column, the stream of gas can contact the droplets in a counter-current fashion and exit through an opening in the top of the column to carry away the ammonia. The resulting aqueous solution that has had ammonia removed therefrom that exits the stripping device can be the fourth aqueous solution.

[0059] The system can include a storage tank configured to receive the aqueous solution comprising nicotine and ammonium hydroxide that has passed through the resin. The system can include a pump operably coupled to the storage tank and the stripping device. The pump can be configured to pump the aqueous solution comprising nicotine and ammonium hydroxide from the storage tank to the stripping device.

[0060] The system can include a thermostatic settler operably coupled to the stripping device and configured to receive the aqueous solution that exits the stripping device. The aqueous solution that exits the stripping device comprises the eluted nicotine from the ion exchange column that has had the ammonium hydroxide removed therefrom in the stripping device. The thermostatic settler can be configured to incubate the aqueous solution comprising the eluted nicotine that has had the ammonium hydroxide removed therefrom at a temperature between 60 degrees Celsius and 210 degrees Celsius to separate the incubated aqueous solution into an aqueous solution comprising a first nicotine concentration and an aqueous solution comprising a second nicotine concentration. The first nicotine concentration is greater than the second nicotine concentration. The aqueous solution comprising the first nicotine concentration can be collected to recover concentrated nicotine. The aqueous solution comprising the first nicotine concentration can be the fifth aqueous solution.

[0061] The system can also include a source of an aqueous solution including nitric acid. The system can include a pump operably coupled to the ion exchange column and the source of the aqueous solution including nitric acid. The pump can be configured to pump the aqueous solution including nitric acid through the strong cation resin. The nitric acid can elute the ammonium from the resin to regenerate the resin. The nitric acid reacts with the ammonium to produce an aqueous solution including ammonium nitrate. The system can include a byproduct tank to which the aqueous solution including ammonium nitrate is directed. The aqueous solution including ammonium nitrate can be used as a fertilizer.

[0062] The components of the system can be made of any suitable material. Preferably, the surfaces that contact the various aqueous solutions are compatible with the aqueous solutions. For example, the compounds of the aqueous solutions preferably do not react with the surfaces of the components of the system that contact the aqueous solutions in an unintended manner. Preferably, the compounds of the aqueous solutions do not sorb to the surfaces of the components of the system that contact the aqueous solutions in an unintended manner. Some plastic materials, such as polyethylene materials, polypropylene materials, and polyvinyl chloride materials, can sorb nicotine. While such plastic materials can be used for surfaces that contact the aqueous solutions, such plastic materials are not preferred.

[0063] As used herein, the singular forms "a," "an," and "the" also include plural referents unless the content clearly dictates otherwise.

[0064] The words "preferred" and "preferably" refer to embodiments of the invention that can provide certain benefits under some circumstances. However, other embodiments can also be preferred under the same or other circumstances. Additionally, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the disclosure, including the claims.

[0065] As used herein, "tobacco" means plant material, such as leaves, stems, or other parts of any of several plants belonging to the genus Nicotiana, such as the N. tabacum species. Preferably, tobacco includes leaves, stems, or leaves and stems.

[0066] As used herein, "aqueous solution" is a composition including water that is fluid at 20 degrees Celsius. The composition can be a solution, a suspension, or the like.

[0067] As used herein, "elute" is the process of extracting one material with another material by washing with a solvent. One example of elution is the exchange of a first ion on an ion exchange resin with a second ion by washing the resin with a solution including the solvent and the second ion (where the first ion is soluble in the solvent) and removing the first ion from the column in the solvent.

[0068] As used herein, "sorption" refers to the retention of molecules or ions in a gas or liquid into a surface or bulk phase. Sorption includes adsorption, absorption, and retention by chemical reaction. Molecules or ions retained by chemical reaction can be eluted provided that a subsequent chemical reaction can release the molecule during the elution process.

[0069] A non-exhaustive list of non-limiting examples is provided below. Any one or more features of these examples can be combined with any one or more features of another example, embodiment, or aspect described herein.

[0070] Example Ex1 A method of recovering concentrated nicotine from cured tobacco, comprising: (i) collecting a first aqueous solution comprising moisture released from cured tobacco, wherein the first aqueous solution comprises nicotine; (ii) passing the first aqueous solution through a strong cation resin to sorb the nicotine; (iii) passing a second aqueous solution comprising ammonium hydroxide through the resin with the sorbed nicotine to elute the nicotine from the resin and form a third aqueous solution comprising nicotine and ammonium hydroxide; (iv) removing the ammonium hydroxide from the third aqueous solution to generate a fourth aqueous solution comprising nicotine; (v) incubating the fourth aqueous solution at a temperature between 60 degrees Celsius and 210 degrees Celsius to cause the fourth aqueous solution to separate into a fifth aqueous solution comprising a first nicotine concentration and a sixth aqueous solution comprising a second nicotine concentration, wherein the first nicotine concentration is greater than the second nicotine concentration; and (vi) collecting the fifth aqueous solution to recover concentrated nicotine.

[0071] Example Ex2 The method according to Example Ex1, further comprising passing a seventh aqueous solution comprising nitric acid through the resin to regenerate the resin and elute the ammonium hydroxide and generate an eighth aqueous solution comprising NH4NO3.

[0072] Example Ex3 The method according to Example Ex2, wherein the eighth aqueous solution comprises an excess of nitric acid.

[0073] Example Ex4 The method according to Example Ex2 or Ex3, wherein the step of removing the ammonium hydroxide from the third aqueous solution comprises contacting the third aqueous solution with a gas stream configured to carry away ammonia from the third aqueous solution in the gas stream, and wherein the gas stream comprising ammonia is contacted with the eighth aqueous solution.

[0074] Example Ex5 The method according to any one of Examples Ex1-Ex4, wherein collecting the first aqueous solution comprises condensing moisture from air in a curing barn.

[0075] Example Ex6 The method according to any one of Examples Ex1-Ex5, wherein the strong cation resin comprises a polystyrene matrix.

[0076] Example Ex7 The method according to any one of Examples Ex1-Ex6, wherein the strong cation resin comprises a sulfonyl group.

[0077] Example Ex8 The method of any one of Examples Ex1 to Ex7, wherein the ammonium hydroxide concentration in the second aqueous solution is from 2 wt% to 20 wt%.

[0078] Example Ex9 The method of any one of Examples Ex1 to Ex7, wherein the ammonium hydroxide concentration in the second aqueous solution is from 5 wt% to 10 wt%.

[0079] Example Ex10 The method of any one of Examples Ex1 to Ex9, wherein the second aqueous solution is flowed through the resin at a rate of from 0.1 bed volumes per hour to 3 bed volumes per hour.

[0080] Example Ex11 The method of any one of Examples Ex1 to Ex9, wherein the second aqueous solution is flowed through the resin at a rate of from 0.5 bed volumes per hour to 2 bed volumes per hour.

[0081] Example Ex12 The method of any one of Examples Ex1 to Ex11, wherein the third aqueous solution comprises a nicotine concentration of 1.3 wt% or greater.

[0082] Example Ex13 The method of any one of Examples Ex1 to Ex12, wherein the third aqueous solution comprises a nicotine concentration of 5 wt% or greater.

[0083] Example Ex14 The method of any one of Examples Ex1 to Ex13, wherein the third aqueous solution comprises a nicotine concentration of from 5 wt% to 10 wt%.

[0084] Example Ex15 The method of any one of Examples Ex1 to Ex14, wherein ammonium hydroxide is removed from the third aqueous solution by a stripping process.

[0085] Example Ex16 The method of Example Ex15, wherein the stripping process comprises contacting the third aqueous solution with a stream of gas counter-current to the flow direction of the third solution.

[0086] Example Ex17 The method of Example Ex16, wherein the stream of gas comprises air or nitrogen.

[0087] Example Ex18 The method of any one of Examples Ex15 to Ex17, wherein the removed ammonium hydroxide or ammonia resulting from the stripping process is contacted with the eighth aqueous solution of Example Ex2 or Ex3.

[0088] Example Ex19 The method of any one of Examples Ex1 to Ex18, wherein the fourth aqueous solution is incubated at a temperature of between 80 degrees Celsius and 150 degrees Celsius.

[0089] Example Ex20 The method of any one of Examples Ex1 to Ex19, wherein the fourth aqueous solution is incubated at a temperature between 80 degrees Celsius and 100 degrees Celsius.

[0090] Example Ex21 The method of any one of Examples Ex1 to Ex20, wherein the fourth aqueous solution is incubated in a settler.

[0091] Example Ex22 The method of Example Ex21, wherein the settler is a thermostatic settler.

[0092] Example Ex23 The method of any one of Examples Ex1 to Ex22, wherein a sixth aqueous solution comprising a second nicotine concentration is combined with the collected first aqueous solution.

[0093] Example Ex24 A system for recovering concentrated nicotine from tobacco curing, the system comprising: (i) a source of an aqueous solution comprising condensed moisture released from tobacco during curing, wherein the condensed moisture comprises nicotine; (ii) an ion exchange column comprising a strong cation resin through which the aqueous solution comprising condensed moisture is passed to sorb the nicotine; (iii) a first pump operably coupled to a source of aqueous ammonium hydroxide and configured to pump the aqueous ammonium hydroxide through the strong cation resin to elute the nicotine from the resin; (iv) a stripping device configured to receive the aqueous solution comprising nicotine and ammonium hydroxide that has passed through the resin, wherein the stripping device is operably coupled to a source of gas, wherein the stripping device and gas are configured to remove ammonia evolved from the ammonium hydroxide in the aqueous solution comprising nicotine and ammonium hydroxide, wherein the ammonia is carried away in a gas stream; and (v) a thermostatic settler operably coupled to the stripping device and configured to receive the aqueous solution exiting the stripping device, wherein the aqueous solution exiting the stripping device comprises the eluted nicotine from the ion exchange column that has had the ammonium hydroxide removed therefrom in the stripping device, wherein the thermostatic separator is configured to incubate the aqueous solution comprising the eluted nicotine that has had the ammonium hydroxide removed therefrom at a temperature between 60 degrees Celsius and 210 degrees Celsius to cause the incubated aqueous solution to separate into an aqueous solution comprising a first nicotine concentration and an aqueous solution comprising a second nicotine concentration, wherein the first nicotine concentration is greater than the second nicotine concentration.

[0094] Example Ex25 The system of Example Ex24, further comprising a condenser operably coupled to the source of the aqueous solution comprising condensed moisture, wherein the condenser is configured to condense moisture released from the tobacco during the curing process.

[0095] According to the system of Examples Ex24 or Ex25, Example Ex26 further includes a second pump operatively coupled to a source of an aqueous solution containing nitric acid, configured to pump the aqueous solution containing nitric acid through a resin, wherein the nitric acid elutes ammonium hydroxide from the resin to regenerate the resin and reacts with the ammonium hydroxide to produce an aqueous solution containing ammonium nitrate.

[0096] Example Ex27, based on the system of Example Ex26, further includes a valve configured to direct the flow of an aqueous solution containing ammonium nitrate to a byproduct tank.

[0097] Example Ex28 is based on the system of Example Ex27, wherein the system is configured to contact the gas stream that has left the stripping unit with an aqueous solution containing ammonium nitrate.

[0098] Example Ex29, based on any one of Examples Ex24 to Ex28, further includes a collection tank for retaining condensed moisture.

[0099] Example Ex30, based on the system of Example Ex29, further includes a third pump operatively connected to a collection tank and configured to pump condensed moisture through the resin.

[0100] Example Ex31, a system according to any one of Examples Ex24 to Ex30, further includes a storage tank configured to receive a solution containing eluted nicotine from an ion exchange column.

[0101] According to the system of Example Ex31, Example Ex32 also includes a valve configured to direct the flow of a solution containing eluted nicotine from an ion exchange column to a storage tank.

[0102] Example Ex33 is a system according to Example Ex32, wherein the valve configured to direct the flow of a solution containing eluted nicotine from an ion exchange column to a storage tank is a valve according to Example Ex27 configured to direct the flow of an aqueous solution containing ammonium nitrate to a byproduct tank.

[0103] Example Ex34, a system according to any one of Examples Ex24 to Ex33, further includes a product tank operatively connected to a constant-temperature settling device and configured to receive an aqueous solution containing a first nicotine concentration.

[0104] Several examples will now be described further with reference to the accompanying drawings, in which:

[0105] Figure 1 A flowchart illustrating a method according to an embodiment of the present invention;

[0106] Figure 2 A schematic block diagram illustrating a system according to an embodiment of the present invention;

[0107] Figure 3 a plot of the concentration of nicotine coming out of an ion exchange column as a function of the volume of aqueous nicotine solution passed through the column;

[0108] Figure 4 a plot of the concentration of nicotine eluted from an ion exchange column as a function of the volume of aqueous ammonium hydroxide solution passed through the column;

[0109] Figure 5 a plot of the concentration of ammonia and the concentration of nicotine in an aqueous solution containing ammonia and nicotine as a function of time as ammonia is removed from the solution by a stripping process; and

[0110] Figure 6 a plot of the concentration of nicotine coming out of an ion exchange column as a function of the volume of aqueous nicotine solution passed through the column after the first use, regeneration, and second use and regeneration, and third use.

[0111] Figure 1 An overview of a method according to one embodiment of the present application is illustrated. The method includes collecting an aqueous solution containing moisture released from tobacco during curing (100). The moisture can be condensed by a condenser to form the aqueous solution. The solution can be passed through a strong cation resin to sorb nicotine from the solution (105). The sorbed nicotine can be eluted from the resin by passing an aqueous solution containing ammonium hydroxide through the resin (110). The ammonium ions will replace the nicotine on the resin, and the solution containing the eluted nicotine will contain excess ammonium hydroxide. The ammonium hydroxide can be stripped from the aqueous elution solution containing nicotine (115). An ammonia stripper column can be used to strip the ammonia, which results in the removal of the ammonium hydroxide in a gas stream. The aqueous solution containing nicotine from which the ammonium hydroxide has been removed is allowed to settle to permit phase separation of the nicotine (120). When settled at an appropriate temperature, the nicotine will separate into a concentrated nicotine phase and a less concentrated aqueous phase. The high concentration nicotine phase is collected (125).

[0112] The low concentration nicotine phase can be recycled within the process (130). For example, the aqueous solution containing the low concentration nicotine phase can be re-settled to cause further phase separation (120), can be combined with the aqueous solution collected containing moisture released from tobacco during curing (100), or can be reintroduced at any other appropriate step in the process. If the concentration of the aqueous solution containing the low concentration nicotine phase is not high enough to settle, some water can be evaporated to concentrate the nicotine prior to re-settling.

[0113] The method can also include regenerating the resin (135) with an aqueous solution containing nitric acid, which results in the exchange of hydronium ions for ammonium ions and regenerates the resin. The regenerated resin can then be used to sorb nicotine (105) from additional aqueous solutions (100) containing moisture released from tobacco during curing. Passing the aqueous solution containing nitric acid through the resin results in the production of ammonium nitrate (145) due to the reaction of ammonium with nitrate. The produced ammonium nitrate (150) can be collected and used as a fertilizer. The regenerated resin can be washed (140) with water to remove excess acid and lower the pH before the resin is reused. The water wash (140) can produce a solution containing low concentrations of nitric acid.

[0114] The ammonia carrying gas stream from the stripping step (115) can be contacted with the resulting aqueous solution from the water wash step (140) or the resulting solution from the nitric acid resin regeneration step (135), which can produce additional ammonium nitrate (145) and remove ammonia from the gas stream before the gas stream is recycled or released to the atmosphere. This can also deplete residual nitric acid.

[0115] As Figure 1 As a result of the method illustrated in FIG. 1, an aqueous solution containing high concentrations of nicotine (125) can be collected from the aqueous solution containing moisture released from tobacco during curing (100), with an aqueous solution containing ammonium nitrate (150) that can be used as a fertilizer as a byproduct, with little or no other waste produced. Thus, the method provides an environmentally friendly way to produce high concentrations of nicotine from an aqueous solution containing moisture released from tobacco during curing.

[0116] Figure 2 An overview of a system 200 according to one embodiment of the present application is illustrated. The system 200 includes source storage vessels 201, 202, 203, 204; pumps 210, 211, 212, 213, 214; valves 220, 221, 222, 223, 224; ion exchange columns 230, 231; product storage vessels 240, 241; an intermediate storage vessel 250; an ammonia stripping column 260; a thermostatic settler 270; a heat exchanger 280; and a condenser 290.

[0117] A condenser 290 can be located in a suitable location in the tobacco curing barn to condense moisture released from the tobacco as it is cured. The condensed moisture forms a first aqueous solution, which can be collected and contained in a storage container 201. A pump 210 is operably coupled to the storage container 201 and is configured to pump the first aqueous solution through ion exchange columns 230, 231. A valve 222 directs the pumped first aqueous solution to either the first ion exchange column 230 or the second ion exchange column 231. When the first ion exchange column 230 approaches or reaches a maximum nicotine sorption capacity, the valve 222 can direct the pumped first aqueous solution to the second ion exchange column 231. The ion exchange columns 230, 231 contain strong cation resin configured to sorb nicotine as the first aqueous solution is pumped through the ion exchange columns 230, 231.

[0118] A storage container 202 contains a second aqueous solution containing ammonium hydroxide. A pump 211 is operably coupled to the storage container 202 and is configured to pump the second aqueous solution through the ion exchange columns 230, 231. A valve 223 directs the pumped second aqueous solution to either the first ion exchange column 230 or the second ion exchange column 231 to elute nicotine from the ion exchange columns 230, 231 and form a third aqueous solution containing nicotine and ammonium hydroxide. Valves 220, 221 direct the third aqueous solution to an intermediate storage container 250.

[0119] A pump 213 is operably coupled to the intermediate storage container 250 and is configured to pump the third aqueous solution through a heat exchanger 280 that heats the third aqueous solution and to an ammonia stripper 260. As the third aqueous solution passes through the ammonia stripper 260, a gas stream from a source storage container 204 is contacted with the third aqueous solution to remove ammonia, which generates a fourth aqueous solution containing nicotine.

[0120] The fourth aqueous solution containing nicotine flows to a thermostatic settler 270, where the fourth aqueous solution is incubated at a sufficient temperature for a sufficient time to separate into a fifth aqueous solution containing a high concentration of nicotine and a sixth aqueous solution containing a low concentration of nicotine. The fifth aqueous solution is collected in a product storage container 240.

[0121] A pump 214 is operably coupled to the thermostatic settler and is configured to pump the sixth aqueous solution to the first storage container 201 for reprocessing through the system 200.

[0122] Storage vessel 203 contains a seventh aqueous solution comprising nitric acid. Pump 212 is operably coupled to storage vessel 203 and is configured to pump the seventh aqueous solution through ion exchange columns 230, 231. Valve 224 directs the pumped seventh aqueous solution to either first ion exchange column 230 or second ion exchange column 231 to regenerate the strong cation resin in the column 230, 231 after the second aqueous solution passes through the column 230, 231. As the seventh aqueous solution passes through the resin, hydronium ions exchange for ammonium ions, which are eluted out, and produce an eighth aqueous solution. The eighth aqueous solution comprises ammonium nitrate resulting from the reaction of nitric acid with ammonia and can contain excess nitric acid. Valves 220, 221 direct the seventh aqueous solution to product storage vessel 241. The seventh aqueous solution can be used as a fertilizer.

[0123] As shown in Figure 2 the seventh aqueous solution can be contacted with the ammonia-containing gas stream exiting stripping column 260 so that the ammonia in the gas stream can react with the excess nitric acid in the seventh aqueous solution to produce additional ammonium nitrate. Thus, the ammonium in the gas stream can be depleted prior to venting the gas stream to the environment, and the excess nitric acid in the seventh aqueous solution can be depleted prior to using the aqueous ammonium nitrate solution as a fertilizer.

[0124] A non-limiting example is provided below that illustrates the use of various steps of the method of the present application to concentrate nicotine. The non-limiting example reflects a proof of concept test to illustrate one or more aspects of the present application.

[0125] Example

[0126] 1. Adsorption of nicotine onto strong cation resin

[0127] An aqueous solution was obtained by condensing the atmosphere in the barn during the curing process of the tobacco. Additional nicotine was added to the concentrated aqueous solution to bring the nicotine concentration to 2380 parts per million. The resulting solution was pumped upward through a bed column of AMBERLITE® IR-120 strong cation resin at a flow rate of 116.94 milliliters per minute, which corresponds to a linear velocity of 1.47 meters per hour. TM IR-120 strong cation resin at a flow rate of 116.94 milliliters per minute, which corresponds to a linear velocity of 1.47 meters per hour.

[0128] A nicotine breakthrough was observed after 1475 minutes. The volume of the nicotine solution that passed through the resin to reach full loading of the resin was 25 liters. Based on these results, the nicotine capacity of the resin was determined to be 1.44 millimoles per milliliter, and the resin was treated with 114 bed volumes (BV) of aqueous solution containing nicotine.

[0129] Samples were taken at the outlet of the column as the solution was pumped through the column. The nicotine concentration of the samples was determined. Figure 3 A plot of the nicotine concentration coming out of the column as a function of the volume of solution pumped through the column is illustrated in FIG. 1. Once the column reached or approached capacity, nicotine was seen to come out of the column.

[0130] 2. Release of nicotine from the resin

[0131] The nicotine sorbed to the resin was eluted by passing a 7.51 wt% ammonia (ammonium hydroxide) solution through the resin. The process was carried out by filling the bed with successive volumes (BV) of ammonia and providing a contact time of 30 minutes between the ammonia solution and the resin. It should be noted that similar results can be expected if operated in a semi-continuous fashion by passing the ammonia solution through the column at a flow rate corresponding to a similar residence time.

[0132] Samples were obtained from the column and the nicotine content of the samples was determined. As shown in FIG. 2, the concentration of nicotine eluted from the column peaked at 16 wt% nicotine. After the resin was contacted with 3.17 BV of the ammonia solution, the nicotine concentration of the effluent solution was very low. Thus, 3.17 BV was considered the amount of ammonia solution required to recover all of the nicotine sorbed to the resin in the column. The average nicotine concentration eluted from the column was determined to be 11.3 wt% as determined by integration of the area under the curve. Figure 4

[0133] 3. Stripping of ammonia

[0134] Due to the large excess of ammonia water used to elute the nicotine from the column, a large amount of ammonia water was contained in the nicotine-rich solution eluted from the column. Thus, the ammonia water was removed from the resulting solution. The solution was passed through a stripping column packed with Raschig rings. The ammonia was removed by a stream of nitrogen. The process was carried out in a semi-continuous fashion, recycling the liquid solution and continuously treating the nitrogen.

[0135] The ammonia concentration in the nitrogen stream exiting the stripping column was determined by high performance liquid chromatography (HPLC). Figure 5 The results of the stripping process are shown, which illustrate that essentially all of the ammonia water can be removed. The ammonia water can be removed with very little loss of nicotine in the solution.

[0136] 4. Separation of the nicotine aqueous solution

[0137] The nicotine solution from which the ammonia water was removed was allowed to settle to cause phase separation. Phase separation will occur when the settling solution is maintained at an appropriate temperature between 60.8 degrees Celsius and 208 degrees Celsius. The nicotine solution separates into two immiscible phases: a high concentration nicotine phase and a low concentration aqueous phase. Because some water remains in the high concentration nicotine phase, for the purposes of the present disclosure, the phase is still considered an aqueous solution.

[0138] ​The nicotine solution from which the aqueous ammonia had been removed was introduced into a thermostatted decanting funnel held at 90 degrees Celsius. After at least 10 minutes, the nicotine separated into two phases. The nicotine concentration in the solution introduced into the decanting funnel, the nicotine concentration in the separated aqueous phase and the nicotine concentration in the separated nicotine phase were determined. The nicotine concentration was determined by spectrophotometric techniques using a wavelength of 258.5 nanometres. The results were confirmed by HPLC. The results are presented in Table 1.

[0139] Table 1. Nicotine concentrations associated with the separation of a nicotine aqueous solution

[0140] Concentration (wt%) Mass (g) Initial solution 11.30 430.95 Separated aqueous phase 8.66 408.09 Separated nicotine phase 77.71 13.63

[0141] The separated nicotine phase contained a concentration of close to 80% by weight nicotine, while the separated aqueous phase contained 8.66% by weight nicotine.

[0142] Two further trials were carried out. The results are shown in Table 2.

[0143] Table 1. Nicotine concentrations associated with the separation of a nicotine aqueous solution

[0144] Experiment 1 (concentration) Experiment 2 (concentration) Initial 7.2 9.6 Aqueous 6.7 7.3 Nicotine 75.8 71.6

[0145] Because a significant amount of nicotine remains in the separated aqueous phase, it is preferred to recycle this aqueous phase to an earlier stage of the process. If the separated aqueous phase is recycled to the thermostatted settler, it can be beneficial to increase the nicotine concentration in the solution by evaporating some water until the concentration is similar to that of the nicotine in the solution initially introduced.

[0146] 5. Regeneration of the resin

[0147] Once the nicotine has been eluted from the resin, the resin in the form of NH4 + is converted back to the H + form for reuse in another nicotine uptake cycle. Although different mineral acids can be used to regenerate the resin, nitric acid is chosen because it can react with the aqueous ammonia to form ammonium nitrate, which can be used as a fertilizer. This fertilizer can be applied to a tobacco crop that can be located close to the curing barn in which the initial aqueous solution containing the nicotine was collected during the curing of the tobacco.

[0148] Regeneration of the resin was carried out using a 5% by weight solution of nitric acid, which was passed through the column (3 BV) over a period of 30 minutes. The column was then rinsed with water to remove excess nitric acid. The solution resulting from the rinsing can contain residual nitric acid, which can be used to convert the stripped ammonium to ammonium nitrate.

[0149] The regenerated resin was then tested for its ability to sorb nicotine and to elute nicotine as shown in Examples 1 and 2 above. Three cycles of sorption, elution and regeneration were carried out.Figure 6 The concentration of nicotine eluted during each cycle is shown in the middle.

[0150] For purposes of this specification and appended claims, unless otherwise indicated, all numbers expressing amounts, quantities, percentages, and so forth, are to be understood as being modified in all instances by the term "about." Also, all ranges include the maximum and minimum points disclosed and include any intermediate ranges not expressly disclosed. Accordingly, in this context, a number A is understood as A ± 2% of A. Within this context, a number A can be considered to include values within the general standard error of a measurement of a property modified by the number A. In certain instances in the appended claims, a number A can deviate from the percentage recited above, provided that the amount by which A deviates does not materially affect the basic characteristics and novel features of the claimed invention. Also, all ranges include the maximum and minimum points disclosed and include any intermediate ranges not expressly disclosed.

Claims

1. A method for recovering concentrated nicotine from tobacco aging, the method comprising: Collect a first aqueous solution containing moisture released from aged tobacco, wherein the first aqueous solution contains nicotine; The first aqueous solution is passed through a strong cationic resin to adsorb the nicotine; A second aqueous solution containing ammonium hydroxide is passed through the resin adsorbed with nicotine to elute the nicotine from the resin and form a third aqueous solution containing nicotine and ammonium hydroxide. Ammonium hydroxide is removed from the third aqueous solution to generate a fourth aqueous solution containing nicotine; The fourth aqueous solution is incubated at a temperature between 60°C and 210°C to separate it into a fifth aqueous solution containing a first nicotine concentration and a sixth aqueous solution containing a second nicotine concentration, wherein the first nicotine concentration is greater than the second nicotine concentration; and The fifth aqueous solution is collected to recover the concentrated nicotine.

2. The method according to claim 1, further comprising passing a seventh aqueous solution containing nitric acid through the resin to regenerate the resin and elute the ammonium hydroxide to generate an eighth aqueous solution containing NH4NO3.

3. The method of claim 2, wherein the eighth aqueous solution contains an excess of nitric acid.

4. The method according to claim 2 or claim 3, wherein the step of removing ammonium hydroxide from the third aqueous solution comprises contacting the third aqueous solution with a gas stream configured to carry away ammonia from the third aqueous solution in the gas stream, and wherein the gas stream containing the ammonia is contacted with the eighth aqueous solution.

5. The method according to claim 1 or 2, wherein the concentration of ammonium hydroxide in the second aqueous solution is 5% to 10% by weight.

6. The method according to claim 1 or 2, wherein the second aqueous solution is flowed through the resin at a rate of 0.5 bed volume / hour to 3 bed volume / hour.

7. The method according to claim 1 or 2, wherein the third aqueous solution contains 5% by weight or higher of nicotine concentration.

8. The method according to claim 1 or 2, wherein the third aqueous solution contains a nicotine concentration of 5% to 10% by weight.

9. The method according to claim 1 or 2, wherein the ammonium hydroxide is removed from the third aqueous solution by a stripping process.

10. The method of claim 9, wherein the stripping process comprises contacting the third aqueous solution with a gas stream flowing in the opposite direction to the flow of the third aqueous solution.

11. The method of claim 10, wherein the gas stream comprises air or nitrogen.

12. The method of claim 9, wherein the removed ammonium hydroxide or ammonia obtained from the stripping process is contacted with the eighth aqueous solution according to claim 2 or 3.

13. The method according to claim 1 or 2, wherein the fourth aqueous solution is incubated at a temperature between 80 degrees Celsius and 150 degrees Celsius.

14. The method of claim 1 or 2, wherein the sixth aqueous solution containing the second nicotine concentration is combined with the first aqueous solution.

15. A system for recovering concentrated nicotine from tobacco aging, the system comprising: A condenser for condensing moisture released from tobacco during aging, wherein the condensed moisture contains nicotine; An ion exchange column comprising a strong cation exchange resin, which allows condensed moisture to pass through the strong cation exchange resin to adsorb the nicotine; A first pump is operatively coupled to an ammonium hydroxide aqueous solution source and the ion exchange column and configured to pump the ammonium hydroxide aqueous solution through the strong cation exchange resin to elute the nicotine from the resin; A stripping device configured to receive an aqueous solution containing the nicotine and the ammonium hydroxide that has passed through the resin, wherein the stripping device is operatively connected to a gas source, wherein the stripping device and the gas are configured to remove ammonia released from the ammonium hydroxide in the aqueous solution containing the nicotine and the ammonium hydroxide, wherein the ammonia is carried away in the gas stream; and A constant-temperature settling device, operatively connected to and configured to receive an aqueous solution exiting the stripping unit, wherein the aqueous solution exiting the stripping unit contains nicotine eluted from the ion exchange column, wherein the ammonium hydroxide has been removed in the stripping unit, wherein the constant-temperature settling device is configured to incubate the aqueous solution containing the eluted nicotine at a temperature between 60°C and 210°C, wherein the ammonium hydroxide has been removed, to separate the incubated aqueous solution into an aqueous solution containing a first nicotine concentration and an aqueous solution containing a second nicotine concentration, wherein the first nicotine concentration is greater than the second nicotine concentration.

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