Jump to:

Lorillard

Investigations Into the Extraction of Nicotine From Tobacco

Date: 07 Feb 1977
Length: 41 pages
00120283-00120323
Jump To Images
snapshot_lor 00120283-00120323

Fields

Author
Reid, J.R.
Type
ACCE, ACCESSION REPORT
BIBL, BIBLIOGRAPHY
CHAR, CHART/GRAPH
LIST, LIST
Area
MINNEMEYER/BASEMENT GMP
Alias
00120283/00120323
ACC966
Named Organization
French Oil Mill Machinery
Copied
Marmor, R.S.
Minnemeyer, H.J.
Slaven, R.W.
Thomas, R.L.
Named Person
Ireland, S.
Document File
00120214/00120405/Dr Jack R Reid
Date Loaded
27 Feb 1998
Request
R1-004
R1-080
R1-041
Characteristic
PARE, PARENT
Litigation
Stmn/Produced
Stmn/Selected
Site
G46
Master ID
00120283/0323

Related Documents:
Brand
Kent
UCSF Legacy ID
lvl88d00

Document Images

Text Control

Highlight Text:

OCR Text Alignment:

Image Control

Image Rotation:

Image Size:

Page 21: lvl88d00
Recommendations for Freon Extraction 1. It is recommended that flavor R& D work with the ammonia treatedtobacco be performed to determine if it is possible to obtain a suitable smoking,product. 2. Pressure extraction studies to determine if 20-40 psi and better agitation would significantly improve the 80-85% extraction efficiency and decrease the time required for each extraction in this batchwise process. 3. Adaptation of a continuous process freon-ammonia extraction technique to minimize time required for the total amount of tobacco extracted. 4. Sequential sulfuric acid scrubbing towers, or an alternate aqueous acid concentration step, to form the high concen- tration of nicotine salt solution to be used for alkaloid recovery, or for direct augmentation of low nicotine, low "tar" tobaccos. The nicotine salt solutions would slightly decrease the hazards associated with transpor- tation and application of the pure alkaloid. 5. Contact corporations associated with~liq,uid-solid extraction techniques and determine the availability of technical consultation~in the extraction of'nicotine from:tobacco for our use, i.e. French Oil Mill Machinery Company. 6. Investigation into the utilization of any isolated "flavor fraction" from the two stage extraction process.
Page 22: lvl88d00
Water Extraction Waste tobacco has been used as a commercial starting material in the manufacture of "Black Leaf 40" insecticide by successive extraction of the nicotine from the tobacco with water. The dilute aqueous nicotine solutions are then concentrated by hiy~ pressure steam distillation into aqueous sulfuric acid. Unlike the organic solvent extraction procedures, the only residue left on the tobacco was water which did not require recovery for an economical process. It was felt that we could use this technique to extract tobacco wastes and recover the nicotine for use in augmen- tation. Additionally, a high nicotine tobacco could be purchased and processed in a similar manner without ex- cessive injury to the tobacco. The tobacco could be reused in a low "tar", low nicotine blend of tobaccos after drying. Preliminary experiments were performed using cut Burley and cut Flue-cured tobaccos in the sequential extraction technique. These experiments were designed to determine the overall extraction efficiency as well as to give a rough indication of the amount of damage to the tobacco. I. Burley Extraction A total of 500.Og of HL '75 Grade cut Burley was extracted in five 100.Og portions. Each 100.0g portion of tobacco was extracted five times with 500.0 ml of water each time in a successive extraction scheme. The following Table 11 represents the extraction pattern and the recovery volumes. The water was separated from the tobacco by draining through a wire screen. TABLE 11 Sequential Extraction Scheme for Small Scale Burley Tobacco TOBACCO ADDED WATER AND FRACTION ADDED WATER RECOVERED FRACTION NUMBER 1. 100.Og 500 ml 180 ml lA 500 ml 440 1B 500 ml 490 1C 500 ml 475 1D 500 ml 620 1E 2. 100.Og 1B + 60 ml 200 ml 2A 1C + 10 ml 440 2B 1D + 25 ml 500 2C 1 530 2 E 500 ml 500 D 2E O O 4A 3. 100.Og 2B + 50 ml 240 ml 3A O 2C 490 3B W 2D 500 3C O 2E 600 3D P 500 ml 600 3E
Page 23: lvl88d00
TABLE 11 (continued) TOBACCO WATER AND WATER FRACTION ADDED FRACTION ADDED RECOVERED NUMBER 4. 100.Og 3B + 10 ml 280 ml 4A 3C 440 4B 3D 500 4C 3E 500 4D 500 ml 540 4E 5. 100.Og 4B + 60 ml 240 ml 5A 4C 450 5B 4D 500 5C 4E 500 5D 500 ml 620 5E The fractions, lA, 2A, 3A, 4A, 5A, B, C, D and E were combined to yield 3210 ml of a dark solution. To this was added 200 ml of 50% sodium hydroxide solution and this mixture was distilled as rapidly as possible to yield 3250 ml of a clear yellow solution. Analysis by capillary GLC indicated 11.3g (78%) of nicotine was recovered. The distillate was brought to pH ti4 with concentrated sulfuric acid and evaporated on a hot plate to 25 ml. Upon cooling the black solution partially crystallized. Addition of 10 ml of distilled water brought the solids back into solution. The tobacco was air dried for 4 days in a hood then at 40°C for 24 hours in a constant temperature drying room (Pilot Plant). This tobacco was slightly broken up but upon cursory examination seemed to be a smokable product. - II. Flue-Cured Extraction A 500.Og portion of cut VLO'73 Flue-cured tobacco was successively extracted'using an identical sequence. The water and extracts were brought to 60°C + 5°C, added to the tobacco and the temperature maintained for 20 minutes. The liquid was drained off the tobacco using a wire screen. The extracts contained 5.Og (88%) of nicotine by capillary GC analysis. These extracts were not worked up. In these extraction experiments the extracts must be processed as soon as possible. Bacterial degradation of the nicotine begins almost immediately as evidenced by mold formation and noticeable frothing within 24 hours. This degradation was more pronouncedin the flue cured extracts, possibly due to sugar fermentation~.
Page 24: lvl88d00
The Table 12 shows the analytical results obtained by comparing the burley and flue-cured tobaccos before and' after sequential water extraction. TABLE 12 Leaf Analysis of Sequentially Extracted Burley and Flue Cured Tobacco Tobacco $ Nicotine % Total Nitrogen Sugars HL '75 Burley 3.39 4.21 0 HL '75 Burley Extracted 0.55 2.87 0 VLO'73 1.38 1.95 11.50 VLO'73 Extracted 0.24 2.09 0.90 There was a nicotine extraction efficiency of 84%' from the cut burley tobacco and 83% from the cut flue cured. In the flue cured extraction, however, over 92% of the total reducing sugars were also extracted. In the burley tobacco, which did not have this problem initially having little or no reducing sugars, the total nitrogen loss in the burley tobacco was 32% of which only 11% was attributable to the loss in~ nicotine nitrogen. This means that the remaining 21% of the nitrogeneous materials were water extractable. The loss of these additional non-alkaloid compounds from both types of tobacco might present either problems in the recovery of the nicotine or organoleptic problems with~ the tobacco. Another potential problem is the fact that, the tobacco rapidly "soured" when air dried. Any larg,e scale operation should include a method for rapid drying. The cut tobacco drier in the pilot plant dried the tobacco but req,uired'4 passes and broke the fibers. This extraction method was highly efficient for extracting nicotine in these small scale determinations. In order to determine any problems which might be encountered upon increasing the scale this extraction scheme was repeated with a larger quantity of cut burley tobacco. In this experiment 10 lbs. of OH-73 cut Burley (4.17% nicotine, 4.54% total nitrogen) was divided into 2 lb. lots. The first 2 lbs. was extracted at room temperature with 5 one gallon portions of water. The extraction vessel was a 6 gal. polyethylene tub equipped with a drainage tap and a wire mesh on the bottom. The mesh served to strain the water from the tobacco and prevent clogging of the tap. In each extraction the tobacco was soaked for 30 min. with
Page 25: lvl88d00
occasional stirring. The first extract was set asid'e and the other 4 reused as extracts for the next 2 lbs. of tobacco with the addition of a fresh gallon of water in the fifth extraction. This type of sequencing was repeated with subsequent lots of tobacco, each time setting the first extract aside. Table 13 gives the order of this sequencing with initial and drainage volumes of each extract. When a drainage volume was less than 1 gal. the extract was topped off to 1 gal. before reuse. Additionally, 1.25 gal. were used in all first extracts to compensate for water loss through absorption by the tobacco. Extracts A-1 through A-5 were combined to give 2 gal. of "primary extracts" and the rest combined to give 4 gal. of "secondary extracts". After extraction the tobacco was dried for 18 hours at 45°C and 4 hours at 110°C. Leaf lab analysis showed the nicotine content had been reduced to 0.66% (an 84% reduction). The concentrations of the first five extracts of this sequence were roughly determined, by capillary vpc analysis, to find the relative efficiency for each extraction. Table 14 shows that the extraction efficiency is over 49% after the second extraction. It was theorized that a large quantity of the nicotine was extracted'on the first extraction and the other four extractions partially act to wash the nicotine from the water absorbed onto the tobacco. An experiment was performed in which only one extraction was used but the initial water volume to tobacco ratio was greater. This large volume of water would allow better washing of the nicotine from the large amount of water absorbed by the tobacco but yield a more dilute solution of nicotine. Since the extraction was performed only once there was less manipulation of the cut leaf particles and less chance that this material would be excessively broken up. A high nicotine tobacco such as HH or OH Burley could have the nicotine partially extracted and still be suitable for blending. The extracted nicotine could then be isolated and added to another blend to augment a high nicotine brand. A 5 1/2 lb. portion of cut OH '73 Burley tobacco was mixed with 4 gallons of water. The suspension was allowed to stand at room temperature (22°C) for 1 hour then the tobacco was drained, using!a wire screen, to yield 3 gallons of liquid'.
Page 26: lvl88d00
- 2 2 - , TABLE 13 Sequential Extraction Scheme for Large Scale Burley Tobacco 2 lb. lot Extract Initial Vol.a Drainage Vol.b Nicotine Conc.c 1 A-1 1.25 0.25 4.56 A-2 1.0 1.0 3.72 A-3 1.0 1.0 2.18 A-4 1.0 0.9 0.54 A-5 1.0 1.0 0.14 2 A-2 1.25 0.3 A-3 1.0 1.0 A-4 1.0 1.0 A-5 1.0 0.9 B-ld 1.0 1.0 3 A-3 1.25 0.4 A-4 1.0 1.0 A-5 1.0 0.9 B-1 1.0 0.9 C-2d 1.0 1.0 4 A-4 1.25 0.5 A-5 1.0 1.0 B-1 1.0 1.0 C-2 1.0 1.0 D-3d 1.0 1.0 5 A-5 1.25 0.5 B-1 1.0 0.9 C-2 1.0 1.0 D-3d 1.0 0.9 E-4 1.0 1.0 a) gallons b) gallons c) g/Q determined by capillary gas chromatography d) fresh water
Page 27: lvl88d00
- 23 - TABLE 14 Recovery of Nicotine from Sequential Extraction Tobacco Recovered Water Concentration of Nicotine total H20 Nicotine Extraction Efficiency 907.18g: 0.95 Q 4.56 g/2 4.3 g 11% 3.79 fC 3.72 g/Q, 14.1 g 49% 3.79 R,' 2.18 g/Q 8.3 g 71% 3.41 k' 0.54 g/Sb 1.8 g 75% 3.79 R,' 0.14 g/Q 0.5 g 78% The water was analyzed by capillary g.c. and found to have a concentration of 4.5 g/Q. This amounts to 52.2g of nicotine recovered. The tobacco was dried for 4 days at 40°C then 18 hours at 100°C. The dry Tobacco had the following analysis: TABLE 15 Leaf Analysis of Tobacco from Partial Extraction Tobacco % Nicotine % Total nitrogen OH '73 4.17 4.54 OH '73 extracted 2.07 3.56 The extracted tobacco contained 50$' of the original amount of leaf nicotine with 52.4g total being lost. The tobacco fibers are not broken up; however, the large amount of water promotes fermentation and the material rapidly "sours". It was not known whether the degradation of the tobacco was caused by the extraction of some fermentation inhibitor by the water, the release of fermentation promoting enzymes by the cutting process or a large increase in the natural fermentation rate of tobacco due to the large volume of water remaining on the tobacco during the slow drying process used here. A rapid drying apparatus which might be applicable to this problem is the whole leaf drier. Currently the whole leaf burley tobacco is channeled through a "burley dip" tank and the very wet cased tobacco is efficiently dried without damage. This apparatus could be used immediately after the extraction of whole leaf material, with either the sequential process or the one extraction partial-nicotine reduction process. In~ this case the water would remain in contact with the tobacco
Page 28: lvl88d00
only during the extraction and would not remain to promote the fermentation processes. Additionally, the tobacco would not require a pre-cutting step and might minimize the particle breakage during extraction. An extraction experiment was performed using!whole leaf burley tobacco to determine the extent of the damage to the tobacco. The one extraction-partial nicotine reduction procedure was used in order to minimize manipulation of the tobacco and'still allow the tobacco to be cut after drying. A 5 lb. portion of the blend of burley tobaccos known as Kent Burley was placed into a 30 gal. polyethylene tank equipped with a drainage tap coveredwith a wire screen. Five gal. of water (25°C) was added and the slurry was agitated by stirring carefully for 20 minutes. The water was drained off through the tap and the leaf material squeezed gently to remove most of the absorbed water. Approximately 4 gal. of water (80%) was recovered'. The tobacco was removed from the tank and dried by two methods: (a) air drying in a hood and (b) a Burley drying oven. A one lb. lot was spread out on a tray in a hood andair dried for 3 days. Surprisingly, no outward signs of decay were noticed during this time unlike the use of cut tobacco. The remaining four lb. sample was passed through a small whole leaf burley drier four times until the tobacco was as dry as possible. The following Table 16 indicates the results obtained upon leaf analysis of the tobacco. TABLE 16 Leaf Analysis of Tobacco from Whole Leaf Partial Extraction Tobacco % nicotine % total nitrogen Kent Burley 2.95 3.95 Kent Burley Extracted 1.61 3.58 This analysis shows that 44% of the nicotine originally present in the leaf was extracted in this experiment. Based upon this analysis the aqueous extracts should have a concentration~of 0.20%. In order to avoid fermenta- tion problems a 100 ml portion of chloroform1was added and the solution was analyzed after standing for 8 days at room temperature. The concentration was found to be only 0.02% in nicotine by capillary vpc. The appearance of molds at the surface of the solution, and the low concentration of nicotine found upon analysis suggests that the add'ed chloroform did not effectively inhibit bacteriological degradation: processes in the extracts.
Page 29: lvl88d00
The heater dried tobacco and air dried tobacco, as well as a sample of unextracted tobacco, were cut and sent for expert panel taste evaluation. 31 The results are listed in Table 17. The extracted tobacco was found to be superior to the original material. Even though no observable damage was seen, the air-dried material was less desirable than the heater-dried sample. TABLE 17 31 Organoleptic Evaluation of Partially Extracted Kent Burley Tobacco Taste Profile A) Kent Burley Medium strength and character,burnt smoky off-taste B) Kent Burley Extracted Slightly milder than A (Burley Drier) with medium character and slight burnt taste C) Kent Burley Extracted Medium strength and (Air Dried) character with slight burnt taste Order of Preference B > C > A One of our largest quantity of tobacco wastes is the stems unfit for the manufacture of reconstituted leaf (RL). It was necessary to ascertain the viability of the water extraction technique as a source of nicotine from waste stems. A sample of such stems (1.07% nicotine) was obtained from the Louisville plant and processed. The manner in which this extraction was carried out was similar to that outlined previously on extraction of nicotine fromburley tobacco. Due to the greater density of stems it was anticipated that their extraction would prove more difficult. Therefore, the following changes in the pro- cedure were mad'e: 1) The extraction was carried out at 75°-80°C instead of at room temperature. This was accomplishedby passing steam through a copper coil inserted into the extraction mixture. The extraction time was extended from 30 min. to 1 hour. 3) A slightly larger volume of water was used in the initial extractions.
Page 30: lvl88d00
Ten lbs. of dry stems were extracted in separate 2 lb. lots. The aqueous extracts were seq,uenced through the individual lots as shown in Table 18. Extracts A-1 through A-5 were combined as the primary extracts and!the remainder as the secondary extracts. Leaf Lab analysis of the extracted stems showed a nicotine content of 0.15% indicating that 86$ of the nicotine had been~ removed. This experiment has shown that extraction of stems can be considered a viable potential source of nicotine. The disadvantages of stems vs. tobacco are three-fold: longer extraction times, higher temperatures, and more dilute extraction solutions. This is due to the highly compacted nature of the stems which makes it difficult for the solvent to reach the inner portion of the dry material. The aqueous nicotine solutions generated'by the water extraction technique have been worked~up by high pressure steam distillation into sulfuric acid. 11 One reported method 32 of recovery, the nicotine as the pure alkaloid, has been the neutrallization of the nicotine sulfate solution with lye followed by a fractional vacuum distillation. Before attempting any workup of the large amounts of dilute aqueous nicotine solution obtained~in our water extraction methods it was necessary to determine the feasi- bility of recoverying the alkaloids from the nicotine sulfate solution. A 60.Og portion of commercial Black Leaf 40 was cautiously treated with 25 g!of powdered sodium hydroxide. This semi-solid was vacuum distilled through a 15 cm vigreaux column for 6 hours until all water had ceased distilling (pot temperature 125°C, unwrapped column). The column was removed and the nicotine vacuum distilled as a clear colorless liquid, b.p. = 110°-117°C/12 mm. The 21g (88%) of product was >99% pure by G.C. and turned pale yellow within 3 days at room temperature. No appreciable amount of nicotine was found in the water which distilled first. The reported use of superheated steam to distill over the nicotine adhering to the sodium sulfate and condenser could bring the recovery much higher. It was interesting to note that when the lye and the dark nicotine sulfate solution was mixed the color was black. Upon distillation the clear nicotine distilled and the sodium sulfate residue was left as white crystals. This suggests that it is not possible to determine the purity of these nicotine sulfate solutions based entirely upon the color of the mixture.

Text Control

Highlight Text:

OCR Text Alignment:

Image Control

Image Rotation:

Image Size: