* CONVERSION OF TURPENTINE INTO TERPINEOL BY ISAAC C. SAWYER THESIS For the Degree of BACHELOR OF SCIENCE IN CHEMICAL ENGINEERING IN COLLEGE OF LIBERAL ARTS AND SCIENCES OF THE UNIVERSITY OF ILLINOIS 1921 UNIVERSITY OF ILLINOIS 1.U 19&L. THIS IS TO CERTIFY THAT THE THESIS PREPARED UNDER MY SUPERVISION BY ENTITLED .TIC CMYSIiSIQlL .QE...TUEP.KimH.I r . 3 ?.l IS APPROVED BY ME AS FULFILLING THIS PART OF THE REQUIREMENTS FOR THE DEGREE OF [ AA > — t - — ^.0. i... . L. .. 1 HEAD OF DEPARTMENT OF Digitized by the Internet Archive in 2015 https://archive.org/details/conversionofturpOOsawy THE SOLUTION OB THE PROBLEM PRESIN T HD IH THIS THESIS WAS LADE POSSIBLE THROUGH THE VALUABLE ASSISTANCE GIVEN AS BY PROFESSOR ROlGEE AD AGS.. I WISH TO EXPRESS’ NY SINCERE APPRECIATION POR TH WHOLEHEARTED INTEREST WHICH. OR. aDaUS’ HAS CONSTANTLY SHOWN IN ...Y WORK. ■ contents. PAGES 1.. INTRODUCTION - -- -- -- -- -- -- -- -- -1-3. 11.. HISTORICAL - -- -- -- -- -- -- -- -- - 4-0 (A) TURPENTINE - -- -- -- -- -- (B ) TERPIN HYDRATE - -------- 6 (C) TERPIN SOL ------------ 7 111.. THE PROBLEM - -- - - -- -- -- -- -- -- 9 IV. . THE .METHOD OF ATTACK - -- -- -- -- -- -- 10-12 V. . DISCUSSION - -- -- -- -- -- -- -- -- - 13-15 VI.. experimental (A) EXPERIMENTS WITH ALCOHOL, ACIDS AND SAWDUST - - - - - - -16-17 (3) HZCHaKICaL STIRRER, ACID CONCENTRATIONS AND TEMPERATURE ---------- 18 (C) ISOLATION OF TERPIN HYDRATE - -'19-20 (D) RECRY STALL 1 Z AT I ON OF TH PIN HYDRATE IN ALCOHOL ------21-22 (E) TREATMENT OF TERPIN HYDRATE TO FORM TERPINEOL ------- 23 VII.. CONCLUSION - -- -- -- ---------- - -24-25 VIII.. 3 13L IQGRaPKY X. INTRODUCTION. Terpineol is ari un saturated alcohol with on»- double bond. It is a tertiary alcohol and exists in four isotropic forms n Ly alpha, beta, gamma, and delta. Each form has different physical properties; the first form , alpha terpineol, has the empirical formula C w H v O . Its structure is C1^C X - ✓ * >* X H- Alpha terpineol has the molecular weight of 154.19, a specific gravity of 0.92b, a melting point of 35 degrees, a boiling point of 218 degrees, and is a white transparent crystal which is insoluble in water. ■ — p ] n h Beta terpineol has the smructux ; 01%-CDH ^ . It h a m 3 > cific gravity of 0.923 a melting point of 32 to 33 degrees, a boiling point of 210 degrees, and is very slightly soluble in water and very soluble in ether and alcohol. In gamma terpineol the double bond is between the side chain ^ r ^ ✓«£ an o t h e r i n g . It has t n ©structure - ^C=.c . T h e w a. w m. •' 3 melting point is 60 to 70 degrees. Delta terpineol is not known to exist in the free state. If it did, it would have the foi C|„H w 0 and the structure _ r> u / J * >3 ^ 3 ClfO >CK-CQR * ^V-i i _ o -i n ; : - £ ^ 1 H J J The different forms of terpineol are isolated by freezing. Terpineol is made in the liquid form. The fact that it exists in this state is probably due to small quantities of a struct- urally isomeric impurity. ( 1 ) . Terpineol has a high specific refraction of ( 1.46 to 1.47 ), The fact that it unites with nyl-carbiraide forming phenyl-urethane, CjH^O jfj. that terpineol is a tertiary alcohol. Terpineol also unite with one molecule of nitrosyl chloride forming \ - 3 C J ■ ST a These last two reactions prove that terpineol has one double bond. When terpineol is oxidized with chromic acid, . it forms ^-00 - y, -■ trioxy t r )i .. - -CO w . The structure of ter- c a wwj pineol was proven by W.H. Perkin Jr., who synthesised terpineol by starting with ethyl cyanoacetate and ethyl -B-iodopropionat e. p pv 1 _ — n l \ c: — , — :ooch v 2 C]n-CE-Cd0-Qr - =c-c<~ a k> a ' x sr hydrolysis with dilute HC1 -C -COOK CO - boil with ( q ' ) ) - istill ' ^Ob-O -COOL 5 * /CH CH„ : ^ _ , * >>• TRSAT with Mg . _ 4 a a X . n - t COCI-CH >0 -C 3 . '•! M ' * * il HBr ’ Q^jpocR ^>Ci3r— CHg # KaQH rhve C] f - ~ d z :ooi / w x 7 ^ p - ^ _ if w a /J pii . nyj - « ^ n ' ^ , --r-i _ rr 1.7 ^ X J. O j. ^ vu i \ ^ \ ^ 1 w * 3 T erpin eol con ’ Per. Lein oxidized terpineol and obtained dicarboxylic acid and ■ c lie acid c 0 ^C: - ■ 3 -,n * 3 — o - .-i; ^ n ' u L/ J -i-41 . w i vJ / p j:COH-CH -olus CH— coon. I _ / z '] ' — Q p £ i" i: " ^ an ‘ -r - x Terpineol occurs in active and inactive forms in lovage oil, cardemom and morjorara oil. The levo form occurs in niaouli oil and the inactive form in cajeput oil. Isomeric oodif ications of terpineol r,r« present in lilac, tuberose, mimosa, plan,-, and . . ' 3 . lily of the valley flower oils. Terpineol is a volatile oil and contains oxygen accompanied by oxygen-free terpenes and some resinous or waxy materials. ' Pfc.fi II. HISTORICAL. Nearly all plants contain volatile, odoriferous liquids called essential oils many of which possess a pleasant odor or taste, and are used in the manufacture of essences and perfumes, many of them are also used in medicine, host essential oils are complex mixtures, and although the characteristics of any one such oil are usually due to the presence of some particular compound, this compound may be accompanied by many others. It often happens that two or more essential oils have two or more components in common, and yet differ entirely in smell, because each contains in addition some highly odoriferous compound which does not occur in the others. The terpene can not be accurately defined, it is more particularly employed to denote certain unsaturated hydrocarbons of the molecular for. ml ',//<• Turpentine, terpin hydrate, and terpineol are in the terpene groups (A) TURPENTINE. The most abundant and the most generally known of all the essential oils is turpentine, which is obtained by making shallow cuts in the stems of pine trees or coniferae, and coll- ecting the sap or juice which flows out. When this sap or juice is distilled it yields ordinary or oil of turpentine and spirits of turpentine. Turpentine is a widely used solvent and becomes scarcer each year, so that lately, even the old stumps have been utilized to produce a cheap grad'*. Oil of turpentine is a colorless, mobile liquid of specific gravity of 0.86, boiling t 5 . It considerable variations in prop- erties according to the species of pine from which it has been obtained.. The oil has a well known odor which is probably due to small quantities of substances formed it by oxidation. On exposure to moist air it is converted into resin and a variety of oxidation products. Th^ oil is practically insoluble in r. . t r but is miscible in most organic liquids. TIUrpentin Li a mixture the principal component of which is a hydrocarbon known as pinene. Pinene is a colorless mobile liquid, specific gravity of 0.858 at 20 dogr» i s, having a odor of turpentine. It boils at 155 degrees and is readily volatile in steam. Pinene combines directly with two atoms of bromine, yielding a crystal of dibromide and with one molecule of hydrogen chlorj giving pinenehydrochloride which has the app arance and odor The other constituents of turpentine are sylvestrene and dipen- Dipentine has a specific gravity of 0.85, and a boiling point of 181 degrees. It is insoluble in water and very soluble in alcohol and ether. The structure of sylvestrene has not been determined but it is very probable that it is similar to that of dipentene. of camphor. The structure of pinene is C term, The structure of dipentene is . . . . • . - . . 3 ag< (B) TERPIN HYDRATE. Terpin hydrate is a white crystalline substance that has a melting point of 117 degrees and a boiling point of the same as that of terpin. This because terpin hydrate decomposes into terpin. Terpin has a boiling point of 258 degrees. The struct- 0 3 u re of terpin hydrate is ^ COH-CH OH— CH_ . It can be CH 3 HOH mad ? by hydrating terpineol in the presence of 60 to 65 percent sulphuric or phosphoric acid at a temperature of BO degrees. Terpin hydrate will not steam distill. Its chief use is for the manufacture of terpineol and it is also used to a considerable extent in medicine. In the National Formulary, fourth edition, there are two prescriptions given in terpin hydrate is used. Elixir Terpini Hydratis et Codeinae. Codeine, two grammes ----------- 2gm. Elixir of Terpin Hydrate, a sufficient quantity to make one thousand milliliters - - - 1000 mils. Elixir Terpini Hydratis et Diacetylmorphinae. D i ac e ty lino rphin e Hy d ro chi o r i d e , Twenty s even hundredths of a gramme -------- -0. 27 gm. Elixir of Terpin Hydrate, A sufficient quantity, to make one thousand millili- ters ------------ 1000 mils. Dissolve the diacetylmorphine hydrochloride in sufficient of the elixir to measure one thousand milliliters and filter. * \ . ■ . - Page 7. (C) TERPXl'iSOL, . In all probability the knowledge of terpineol dates back to the days of tne Chaldeans. These people were well learned in tne making of perfumes and therapeutics, because of .its therapeutic property, it was used by these people in there embalm- ing fluids. Probably the plant from which they obtained terpin- eol was the Syringa Vulgaris. This plant is a native of Persia but fully acclimated in Europe and America. It is known in this country as lilac and the oil from its flowers contain a fraction between 210 and 220 degrees which possesses a lilac odor of a very pronounced degree. This fraction is terpineol. To get the sweet and flowery odor from terpineol it should be diluted with very pure alcohol. This dilution is eight ounces of terpineol to one gallon of alcohol. Concentrated terpineol will not give a sweet odor, because the odor given off is to intense. Flowers only give off small quantities of perfume at a time so the dil- uting of this concentrated terpineol is merely duplicating con- ditions existing in nature. All lilac flower oils contain a large percentage of terpineol. Many shadings of this lilac -odor are obtained by varying the percentage of this ingredient. The odor groups of terpineol are probably the OH and the CH 3 groups - .. Traces of by-products sometimes present in terpineol not large enough to be found by chemical tests will often ser- iously interfere with the odor. To eliminate impurities the oil should be vacuum distilled three or four times. The by-product most likely to be present in terpineol is turpentine and it can be determined by fractionating a small sample of the oil: if ten percent of the first run of the distillate shows a decided - • , . • . Pare 8 change in the angle of rotation towards the left, the possibil ity of its presence is excluded. The common terpineol , much used as a soap scent, is a syrupy oil looking like glycerine.. During the last century it has been manufactured by the very expensive method of allowing the mixture of turpentine, ethyl alconol and nitric acid to stand for seven days. ■s - ' Page V. III. THU PKOBLEk. The problem was to work out a process which could be used on a commercial scale for the conversion of turpentine into terpineol. Tin. > 1 ct , rora th< _ • ter- pene oils, because of its low cost and plentiful and readily accessible supply. The ideal striven for w as to obtain the maximum yield at the minimum cost in the shortest time possible. . . Page 10. IV. CJiB METHOD OP ATTACH. The first in the solution of this problem was to obtain all the information ppssible about the different substances which were to be experiment with. Some of this information was found in organic text books and the rest of the information was obtained from Richter, Beilstein and various serials. All the references that had direct bearing on the problem were abstract- ed, The serials which were referred to were The Jour. Chem. ’oc. , Jour. Am. Chem. Soc. , Bull. soc. chim. , Patent Anmeldung, Fried - 1 a end or, Berichte, Jahresbericht e, Monatsch, Z.Phys. Chem., Arch. Pharm. , J. prakt. Chem. , J. RUSS. Phys. Chem. Soc. , Comptes rendus, Chem. Z'entr. , J. Biol. Chem., then some information v:as obtained from Vanino, and the U..S. Patents. The following pro- cesses are abstracts. TERPIU HYDRATE. (1). Take 400 grams of refined American or French oil of turpentine, 350 c.c. of alcohol specific gravity 0.831, (80 vol. of alcohol 20 vol. of water) and 80 c.c.. of nitric acid specific gravity 1.3, and let this mixture remain in a wide shallow porcelain dish at normal temperature for one day. Then neutral- ize it with alkali, filter dry and recrystallize in 96 percent alcohol. Terpin hydrate is soluble in 32 parts of boiling water, 250 parts of water at 15 degrees, 10 parts in alcohol, 100 parts in ether, 200 parts in chloroform, slightly soluable in turpentin . 1. J.,Chem. Soc. (1899) . 1 Page 11. TERPIN HYDRaTL (2). Agitate terpineol with 80 percent phosphoric acid at 30 degrees, it becomes a homogenous solution and crystals of terpin hydrate separate. Less complete action is formed by 60 percent sulphuric acid. Treat terpinene dihydrobromide at zero degrees with silver acetate in glacial acetic acid. Treat limonene hydro- chloride with an excess of two percent aqueous potash at 50 to 60 degrees. Treat linalool in three times its weight of acetic acid and one half percent sulphuric at a temperature below 20 degrees to obtain parts of d -terpineol and 10 parts geraniol. d-Linalool is converted in a similar manner to 1-terpineol by using formic acid. Terpineol is obtained by mixing pinene, alcohol and nitrous acid purified from nitric acid and leaving the mixture at ordinary temperature for about two months. Neutralize and steam distill at reduced pressure. To a 100 parts of linalool, geraniol and citron el mixed, at ten to fifteen degrees with a 100 parts of acetic acid and three to ten parts of sulphuric acid. Agitate the mixture and keep the temperature below 30 degrees. After the mixture becomes homogenous mix it with water so that the oil is separated. _ Alpha Terpineol (3) TERPINEOL (4). TEBPIN250L (5). TELPILEOL (6). Chem. Soc. ii ti ti ii (1917). (1907). (1899). 5. Comptes rendes (1901). 6. Friedlaender (1394-1897) * fr r . . * . Page 12. TERPIN HYDRATE ( 7 ). Saturate saw dust with turpentine and treat the mixture with a dilute solution of sulphuric acid, ilacerate the solution and remove the acid and non-converted oil. Wash trie substance with a solution of sodium carbonate. Extract the terpin hydrate from the saw dust with a solvent. TEKPINEOL (3). Take three of greek oil of turpentine 43 degrees dextra- rotary and add with constant stirring two parts toluic sulphonic % 62 percent. The temperature is kept at 19 degrees. Continue stirring until a homogenous solution is formed.. This takes from five to seven hours. Then add four to five parts of water, neutralize and steam distill the separated oil. TERPJNEOL ( 9 ) . Treat 25 grams of terpin hydrate with a 100 c.c. of sulphuric acid, 33 percent. Reflux mixture for one hour. Separate the oil,, neutralize and steam distill. 7.. (J. S. Patents. Vol. 126.. 3, Friedlaender (1907,-1910). 9. Annul en der Chemie (230). ' . . . Page 13. V. DISCUSSION. It is obvious from the processes which are given on the preceding p ;;es that they are acid concentration and temperature reactions. Then if the proper concentration is kept and the temperature allowed to vary, the exact temperature can be de- ter airied at which the .maximum yield is obtained with that con- centration. After this temperature is determined, it should be kept constant and the cone entrat ions varied until a maximum yield is obtained.. IN these processes there is not one in which terpineol is made directly from turpentine.. This would lead one to be- lieve that if it were possible to make terpineol from turpentine directly that some one would have done it.. It is also obvious from these processes that turpentine can only be converted into another substance by treating it with a strong acid at a low temperature and that terpineol is made by the treatment of ter- pene oils v/ith a dilute acid. Then if turpentine will only change its form when treated, with an acid of high concentration, it would be impossible to make terpineol direct from turpentine, because terpineol is made by an acid of low cone entrat ion react- ing ith a terpine compound. Van in o ’ s method for the preparation of terpin hydrate could not be used on a commercial basis, be- cause of the expense. In this process alcohol is probably used, because it can be diluted so that it will have the same specific gravity as turpentine.. This alcohol would have a stronger ten- dency to bring the acid into contact with the turpentine than a liquid of a higher specific gravity. The trouble with most of the processes in the literature is that the acid is in one . , . . . . Page 14. layer and the turpentine is in the other. For this reason it takes several days for the reaction to taxe place. If the concentrated acid is added directly to the turpentine at ordin- ary temperatures , it would decompose the turpentine. One way to "bring the acid into contact with the turpentine is to sat- urate the saw dust with turpentine and treat this mixture with acid. If it were possible to treat the turpentine with an acid solution that would diffuse into the turpentine then the reaction would take place in a few minutes but the turpentine has a strong tendency to exclude any acid solutions. In the process in which terpin hydrate is made from terpineol by the agitation of a solution of terpineol and a strong acid , one might be lead to believe that it would be possible to make terpin hydrate by a similar reaction from turpentine. In the experimenting one should attempt to find the cheapest acid that will ;ive 'ood results. If a process is worked out for. the conversion of tur- pentine into terpin hydrate, the next step is to work out a process for the conversion of terpin hydrate into terpineol.. in this process the difficulty will arise as to how to isolate the terpin hydrate from the mixture. Terpin hydrate will de- compose in € strong acid solution if the temperature is not kept ciose to zero degrees. Brobably the best way to treat this difficulty is to dilute the mixture with ice and suck the ter- pin hydrate as dry as possible and then neutralize the mixture with a dilute alkali. The remaining turpentine can be separated from the terpin hysrate by steam distillation. Terpin hydrate can be recrystallized in 9 G percent alcohol. In experimenting with terpineol it is best to try acids . . . i Page 15. of weak cone entrat ions, because acids of strong concent rat ions will convert terpin hydrate or oils of the terpene group into oils of lower boiling points than that of terpineol or the strong acid will decompose the substance into resinous matter.. In the process where terpineol is made from linalool, geraniol and citronel only one percent of sulphuric acid is used, how, if terpin hydrate is treated with one percent of sulphuric acid at ordinary temperatures there is no reaction and if terpin hydrate is refluxed with 33 percent of sulphuric , it is con- verted into oils of lower boiling points than that of terpineol.. Since terpin hydrate will react with acids of low concentrations at high temperatures, then tests should be made along these lines. A certain amount of terpin hydrate should be refluxed with dilute sulphuric which in each test has a different con- centration. A series of these tests should be run until that concentration is found which gives the maximum yield from terpin • hydrate. Enough solution should be used in each test so as to completely cover the terpin hydrate. Then the oil which sep- arates should be neutralized and fractionated to determine the amount of terpineol. The time should be varied so as to deter- mine the shortest time necessary to complete the reaction. The data obtained from the experiments will show how to get the maximum yield of terpineol from turpentine at the minimum cost in the shortest time for the most convenient process. , . . . Page 16. VI. EXP31U I iiEK T aL . (a) The first in the experimenting was to find which acid gave the best results. The same amount of turpentine and the sa ue amount of alcohol or acetic acid was used in each one of these tests.. In some of the processes found in the literature terpin hydrate was made from turpentine by treating a certain amount of the turpentine with an equal amount of the acetic acid or the alcohol. The acids which, might be used in this pro- cess are sulphuric, nitric, hydrochloric and formic. The react- ions were carried out in wide porcelain dishes. The data obtained from these tests is in the following table. Turpentine Alcohol Acetic Acid 20gr. Acid Temp. Time Yield sp.gr. 0. 875. 95;£ lOOgr. lOOgr. II " 100 II " 100 ff " 100 II it 100 II Prom the result sulphuric acid gives a greater tendency to 100 100 100 100 sulphuric 25-30 7 days 13gr Q n i t r i c hydrochloric 11 phosphoric f o rm i c 1 00 10 s in the above table it is obvious that the largest yield or that turpentine has react with sulphuric than with any of the . . . . . . Page 17 other ac ids that were used. .T ust what et 1 ec t the acetic c iiu The results of the experiments performed indicate that the maximum yield for the conversion of turpentine into terpineol is 73 percent, The first step in this process is to convert turpen- tine into terpin hydr< te. T t 4,3! by weight of turpen- tine (sp.gr.) in a uechanical st 1:.. c with a cold nixture of three parts by weight of sulphuric acid (sp.gr. 1.84), and 2 parts by weight of water. Care should be taken that the sulphuric acid solution is added slow enough to the turpentine so as not to raise the temperature' of the mixture more than three degrees. This mixture is stirred at zero degrees for eight hours. 3y the end of this time the mixture is convert- ed into a red colored, >genous substance. This is poured into a receptacle and two parts by weight of ice are added. The mixture is stirred for several minutes and allowed to stand two hours. Then let the mixture drain for 48 hours, suck dry and wash first with water and then with sodium carbonate solution until the washings are neutral and wash out the sodium carbonate with water.. Any coloring matter in the terpin hydrate may be washed out with dilute alcohol. The next step is to separate the unconverted turpentine from the terpin hydrate by steam distillation. Recrys- tallize the terpin hydrate by dissolving one part by weight into 1. 57 parts of 95 percent alcohol cl boiling temperature. Filter this solution through a hot suction funnel and dilute the alcohol- ic mixture with three parts of water. The terpin hydrate is sep- arated by filtering. Terpineol is made from terpin hydrate by refluxing at ' ■ ' ' . .. . ' |S $ . ■ * . * ♦ • . , f . ' ) .. • . • . • '• ; ' , .. i p 125 degrees for two hours a mixture of one part by weight of terpin hydrate with one and a half parts of water containing 0. 009 parts by weight of sulphuric acid (sp.gr. 1.84),. The ter- pineol is separated and washed with water until the washings are neutral. The oil is then distilled under diminished pressure. The ^ield is 90 percent. The by-products from this process will be turpentine, sulphuric acid, alcohol and resinous material. The first three by-products cah be reclaimed and used over. If terpineol cost eight times more than turpentine , then the profits of the process are about S00 percent. Terpineol has a composition very similar to that of linalool, geraniol, citronellol, citronel and citral. The larket price for these oils is much higher than it is for Lneol.. Probably if the proper acid is used along with the exact temper- ature and acid concentration, turpentine can be converted into any one of these oils. The process given in PRIED., ' 1894-1897 ) , converts linalool, geraniol and citronel into terpineol. In the process given in the J,.Chem. Soc. (1899), linalool is converted into terpineol. In the J.Chem. Soc. (1895), aprocess is given for the decomposition of terpin hydrate into acetic acid and oxalic acid.. Since this reaction will take place, terpin hydrate ought to be made on a commercial scale by the synthesis of acetic and oxalic acid. In the process in the J. CJhem. Soc. (1893 ) , terpineol is decomposed into cynene. Since this reaction takes place, cynene might be converted into terpineol. .Also cymene is made by heating oinene dibromide at a moderately high t emper&ture&nd dipentene can be made by heating isoprene to 260 degrees.. Page 26. VIII. BIBLIOGRAPHY. Terpin eol. Journal of the Chemical Society (1917) l-p513. Journal of the Chemical Society (1907) l-ol059. " " " " " " 1- P 228. a ii ii it M ii 1-64 Annalen der Chemie (230, p225. ). " " " (230, p253. ). U. S. Patents. Volumn 9b, pl594. Friedlaender (1894-1897) pl306. Journal of the Chemical Society (1899) p63. J. pr. Chera, (1898) (ii) 58, pl09. Comptes rendu s (1901) 132, p637. Annalen der Chemie (350, pl55. ). Comptes rendus (1907) (i) ol62. Hagers Handbuch der Pharmazeut ischen Praxis, Vol. II. Terpin Hydrate. U. S. Patents, Volume 126. p642. Friedlaender (1907-1910) oil 62. Journal of tne Chemical Society (1395) p548. Cnemisches Zentralblatt II, p419. (1897). " " " p420 ” Ph. Ch. (27 ) pb43. Berichte (35) p<155. Chemisches Zentralblatt II, p417. (1897). Terpene Berichte (27) pi 651. " (29) pi 3. " (32) p57. Cornptes rendus (1901) I olOOo. " " M fl p784. " " (1902) « pi 059. J. pr. (ii) (66), p49. Comptes rendes 134, p360. - /