Examination of Chinese Wood Oil. - Industrial & Engineering

Ind. Eng. Chem. , 1914, 6 (10), pp 806–809. DOI: 10.1021/ie50070a009. Publication Date: October 1914. ACS Legacy Archive. Cite this:Ind. Eng. Chem. ...
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T H E J O U R N A L OF I N D C S T R I A L A N D ENGINEERIXG C H E M I S T R Y

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for cineol. To t h e well-cooled oil, glacial phosphoric acid was slowly added according t o Scammel's pr0cess.l After decanting as much of t h e oil as possible t h e magma w a s placed i n a Buchner filter, t h e filter placed i n a centrifuge cup a n d centrifuged; in this way we were a b l e t o get t h e m a g m a fairly d r y without t h e loss of a n y of t h e adhering oil. After decomposition of t h e phosphate with hot water. a pure oil was obtained, which melted a t -1' C . T h e cineol t h u s obtained constituted 30 per cent of t h e whole. T h e cineol was also identified b y t h e formation of t h e iodol which, a f t e r recrystallization from benzene, melted a t I I III2O.

T h e oil remaining i n Fractions 3 t o 7 after t h e rem o v a l of t h e cineol constituted approximately 2 5 per c e n t of t h e whole. This p a r t of t h e oil was optically inactive a n d t h e boiling point a n d specific gravity ind i c a t e d either terpinene or dipentene. An a t t e m p t was m a d e t o form t h e dipentene tetrabromide, b u t although crystals separated t h e y were not in sufficient q u a n t i t y t o be identified. On t r e a t m e n t of t h e oil with Beckm a n n ' s reagent* (30 p a r t s water, 6 p a r t s potassium d i c h r o m a t e a n d j p a r t s sulfuric acid), a h e a v y brown precipitate separated which showed t h a t a considerable portion of t h e oil consisted of terpinene. Fractions 8, 9 a n d I O were subjected t o a freezing mixture of ice a n d hydrochloric acid, a t e m p e r a t u r e -20' being a t t a i n e d . Solid crystals amounting t o z j per cent of t h e t o t a l oil separated. After t h e first sublimation these crystals showed slight optical act i v i t y , b u t after t h e second sublimation were optically inactive. T h e y melted at 1 j 3 O C. Pure camphor melts a t I 7 j '. T h e semicarbazone prepared according t o t h e method of T i e m a n x ~ , melted ~ a t 232'. The Unsemicarbazone of camphor melts a t 236-238'. d o u b t e d l y these crystals were camphor. After t h e removal of t h e camphor there remained approximately I O t o 1 2 per cent of t h e original oil. T h e boiling point was zoo' C . , specific gravity 0.917'. a n d specific r o t a t i o n a b o u t 2j.9': T o a solution of t h e oil i n petroleum ether, bromine was slowly added according t o t h e method of Wallach4 for preparing thujone trib r o m i d e ; crystals were obtained which, after twice recrystallization from ethyl acetate, melted a t I 231 2 4 ~ . Thujone tribromide melts a t 1 2 2 ' . A small q u a n t i t y of oily substance remained from Fractions 8, 9 a n d I O after t h e separation of t h e camphor a n d t h u j o n e ; t h i s was a resinous oil, probably p a r t l y formed b y polymerization during t h e process of distillation, a n d partly consisting of other high boiling terpenes which occurred in quantities too small t o be definitely determined. Pinene.. ...,. , , . , , , , , Cineol . . . . . . . . . , . . . . . Dipentene, terpinene. etc.. . . . . . . , . . , , , . , 4 Thujone . . . . . , . . . . . . . 5 Camphor.. . . . . . . , . . . 6 Resinous material., . . , 1

2 3

Analysis by Bureau Our of Plant Industry analysis 6 . 0 per cent ? 3 0 . 0 per cent 2 2 . 5 per cent ? Trace 4 0 . 0 per cent ?

2 5 . 0 per 8 0 per 25 .O per 5 . 0 per

cent cent cent cent

A comparison of our analysis with t h a t of t h e Bureau 1

2 3 6

U. S. Pharm.,'1900, p. 313 Baeyer. Ber., 27, 815. Tiemann, I b i d . . 28, 2191. A n n . . 275, 196; 286, 129.

Val. 6 , K O . I O

of P l a n t I n d u s t r y gives a good indication as t o t h e variation of t h e constituents of t h e oil with t h e season. A t t h e earlier season a t which we obtained our material, t h e oil contains a considerably higher percentage of t h e lower boiling constituents, while a t t h e later period a somewhat greater percentage of camphor was found. CHEMICALLABORATORY UNIVERSITYOF CALIFORNIA BERKELEY

EXAMINATION OF CHINESE WOOD OIL' B y E. E. WARE A K D C. L. SCHUXANN

T h e use of Chinese wood oil as a varnish oil, although of fairly recent adoption, except i n t h e Orient, has increased rapidly until a t t h e present time wood oil has come t o be considered t h e i m p o r t a n t oil of t h e varnish industry. The value of t h e oil has been said t o lie in i t s ability t o form actual combinations with the abietic acid of t h e rosin with which i t is cooked. This s t a t e m e n t may be open t o question, b u t t h e fact remains t h a t varnishes of superior quality can be made from wood oil a n d rosin when t h e y are properly manipulated. Most of t h e Chinese wood oil imported into t h e United States is gathered in small quantities througho u t t h e rural districts of western China, a n d after passing through t h e h a n d s of several native collectors a n d dealers, reaches H a n k o w , where i t is p u t i n t o t h e export packages. T h e American buyer, although reasonably certain t h a t he receives t h e oil as packed a t H a n k o w , has no assurance t h a t t h e oil he buys is representative of t h e oil a s pressed from t h e n u t . T h e wide variations t h a t t h e varnish-maker finds i n t h e oil as he uses i t m a y be due t o variations in t h e n u t a n d in i t s t r e a t m e n t , or t o adulteration by one or more of t h e various middlemen during i t s openbasket travel from interior China t o t h e forwarder's warehouse a t Hankow. METHODS O F EXAYIh-ATIOX

S u m e r o u s methods have been proposed for t h e determination of t h e relative p u r i t y of wood-oil s a m ples. Polymerization of t h e oil b y heating a t a definite t e m p e r a t u r e for a definite length of t i m e , various modifications of which t r e a t m e n t have been proposed b y Bacon, Worstall, Potsdarner, Browne, a n d others,2 is t h e method in most general use a t t h e present time. This method seems t o have given t h e most satisfaction, since t h e analytical constants of wood oil v a r y within r a t h e r wide limits, a n d t h i s variation does not seem t o be accompanied b y a corresponding variation in t h e working qualities of t h e oil, as judged b y i t s action in t h e 1-arnish kettle. However, m a n y buyers prefer t o depend upon t h e analytical constants i n passing judgment on wood oil, claiming t h a t t h e personal equation h a s too strong a n influence on t h e results obtained b y t h e heat polymerization method. T h e iodine number a n d t h e re1 Presented a t the 17th Annual Meeting of t h e American Society f o r Testing Materials, rltlantic City, June 30 t o July 3 , 1914. 2 Boughton, "Testing of Chinese Wood Oil," Proceedings A m . Sac. Test. M a t s . , 13 (1913), 923.

OCt.. I914

T H E J O U R N A L O F I N D U S T R I A L .4ND E N G I A V E E R I N G C H E M I S T R Y

fractive index' seem t o be t h e most reliable constants t o use. hIcIlhiney2 offers a method for t h e examination of this oil t h a t promises well when standardized. H e precipitates t h e insoluble iodine addition products formed when wood oil is treated wi'th icdine in acetic acid solution, and weighs t h e oil remaining after evaporation of the solvent f r o m the filtrate. LIGHT BREAK

A familiar characteristic t h a t seems t o have been neglected in t h e consideration of methods for judging the purity of wood-oil samples, is t h e light "break." I t is a well-known fact t h a t wood oil exposed t o t h e light in bulk soon exhibits a flocculent white precipitate, which continually increases in a m o u n t until, after some months, t h e oil seems t o be a solid white mass. This change in wood oil upon exposure t o light is reported b y Normann3 t o be a polymerization. Fahrion4 does n o t agree with this view b u t calls t h e change a molecular transformation. Normann also finds t h a t light has a similar effect upon t h e potash soap of Chinese wood oil a n d t h a t t h e transformation takes place more rapidly t h a n with t h e oil. This break caused b y sunlight seems t o be characteristic of mood oil alone, a n d seems t o be capable of standardization t o t h e point t h a t permits its use as a n analytical method for t h e estimation of t h e purity of wood-oil samples. T h e authors in studying this phenomenon have made use of certain catalytic agents t h a t markedly influence t h e r a t e of transformation. Among these are iodine, sulfur,s hydriodic acid, sulfur chloride, carbon dioxide, hydrogen sulfide, phosphorus tribromide, a n d carbon bisulfide.6 These agents a c t a t differe n t rates, a n d bring t o completion, in times varying from a few hours t o several weeks, a reaction t h a t Morrell' reports as proceeding only t o the extent of 6 per cent in one year. Sulfur chloride a n d iodine are t h e only accelerators studied t h a t will cause a complete precipitation within t h e time t h a t permits the operation t o be classed as a n analytical method. Others of the catalyzers might be used a s a means of getting a less contaminated product €or t h e examination of its characteristics. The action of sulfur chloride upon t h e drying and semi-drying oils is common knowledge. Jenkins* reports t h e fact t h a t sulfur chloride added t o wood oil t o t h e extent of 20 per cent will yield a jelly-like mass. The reaction is accompanied b y a n evolution of hydrochloric acid a n d considerable heat. Chinese wocd oil is not alone in exhibiting this characteristic, some of t h e semi-drying oils showing quite as energetic an action toward sulfur chloride. T h e fact t h a t such compounds arc formed m a y not therefore be accepted as a test for t h e purity of wood oil. Gardnerg suggests Wise, THISJOUHXAL, 4 (1912), 497. I b i d . , 4 (1912). 496. ' Chem. Z t g . , 31 (19071, 186. 4 Chem. Ceniulbl., 83 (1912), 2154. Maquenne, Compt. rend., 135 (1902), 696. l

2

Andes, "Iron Corrosion and Anti-Corrosive Paints," p. 156. T r a n s a c t i o n s Chem. Soc., 101 (1912), 2082. J. Soc. Chem. I n d . , 16 (189i), 195. P r o c e e d i n g s .Ani. Sac. Test. M a t s . , 13 (1913), 946.

807

t h a t as Chinese wood oil in carbon tetrachloride solution will form this addition product much more rapidly t h a n will other oils under t h e same conditions, t h e action might be susceptible t o a time standardization. If t h e wood oil be thinned with a solvent upon which t h e sulfur chloride will not act, a n d t h e dilution be t o a strength of solution of 20 per cent or less, t h e sulfur chloride t h e n becomes merely a catalytic agent for t h e transformation of t h e wood oil b y light, a n d there seems t o be very little if a n y addition product formed. The oil mill break t o a considerable extent even in t h e dark, b u t t h e reaction is very much more rapid if exposed t o light. If t h e concentration of t h e sulfur chloride be low and t h e mass cool, t h e reaction will proceed until within a few hours the oil is of t h e consistency of lard. I n order t h a t the reaction proceed t o completion i t is necessary t h a t t h e break be filtered o u t a t intervals. T h e reaction between Chinese wood oil and iodine has been used a s a qualitative,' and t h e modification introduced b y hIcIlhiney as a quantitative method for t h e estimation of t h e purity of wood oil. If we carry the thinning still further t h a n is recommended b y McIlhiney, and use petroleum ether instead of glacial acetic acid, the addition of 0.3 Fer cent of iodine will give practically no additional products, b u t will accelerate t h e transformation of t h e oil into t h e insoluble elaeostearic glyceride of Fahrion. A N A L Y T I C A L M E T H O D N O . I-The authors' procedure is a s follows: Five grams of t h e oil t o be examined are weighed into a small beaker, thinned with 2 j cc. of petroleum ether (60" C. b . p . ) , and t h e whole cooled t o o o C. After cooling, j cc. of ice-cold, saturated solution of iodine in petroleum ether are added with stirring. Precipitation s t a r t s within a few minutes; the better the light the quicker t h e precipitation. After about I hour, more petroleum ether is a d d e d a n d the mass stirred thoroughly. T h e first filtration should t a k e place after about 3 hours. t h e precipitation having proceeded b y t h a t time t o show a conversion of about jo per cent of the wood oil present. Little is gained b y waiting longer before filtering, a s t h e precipitate is so heavy a s t o mask the further action of light upon the oil. The filtrate from t h e first filtration is cooled and again exposed t o light. A few milligrems of iodine in solution may be added a t this pcint if t h e solution has become colorless. Three precipitations with the corresponding filtrations are generally sufficient t o give total yield. T h e solution should be ,kept cold a t all times during precipitation, although after each filtration t h e extra petroleum ether may be evaporated on t h e steam b a t h , if the solution be thoroughly cooled before the further addition of iodine and t h e esposure t o light. The material taken out by t h e third filtraticn is of somewhat different character from t h a t precipitated earlier in the operation. This may indicate the presence of a third glyceride as a constituent of wocd oil, and may account for t h e difference of opinion between Cloez,'l who claims jj per cent elaeomargaric acid and '

2

Boughton, J. Soc. Chem. I n d . , 28 (1909). i 1 9 Compl. rend., 8 1 (187.5). 469.

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T H E J O U R N A L O F I S D C S T R I A L ,iAVD E - V G I A V E E R I S G C H E M I S T R Y

808

2 j per cent oleic acid, a n d Fahrion‘ who finds 90 per cent a n d I O per cent. I n Table I are compiled t h e d a t a obtained b y t h e

use of t h i s method i n t h e examination of several Chinese wood oils a n d of other samples in which Lhese oils were mixed with varying a m o u n t s of sesame a n d s o y a b e a n oil. T h e figures i n t h e column entitled “ A d u l t e r a n t (calculated)” were obtained a s t h e difference between t h e actual weight of t h e residue a n d t h e calculated weight, using 7 per cent of t h e weight of t h e wood oil i n t h e sample a s t h e average weight of residue obtained from pure oil. I n cases where t h e figures show negative, indicating a n actual weight less t h a n t h e calculated, t h e figures were inserted merely t o show t h e extent t o which t h e inaccuracy of t h e m e t h o d is a p p a r e n t . The results i n Table I indicate a precipitation of approximately 93 per cent of t h e wood oil present, w h e n using iodine as a catalyzer. Sulfur chloride does n o t seem t o be so efficient in i t s action upon t h e raw oils. T h e precipitation proceeds a t a slower r a t e , a n d t h e r e seems t o be a strong tendency for t h e material t o skin over with a n oxidized film during t h e precipitat i o n . N o q u a n t i t a t i v e results on sulfur chloride precipitation are included i n t h e table. T h e method of estimation used in arriving a t t h e figures given i n Table I is the weighing of t h e final filtrate after evaporation of t h e petroleum ether. T h e a m o u n t of adulteration m a y be considered as t h e weight of t h e filtrate minus t h e a m o u n t of t h e residue due t o t h e unprecipitated olein present in t h e wood oil. This a m o u n t of unprecipitable m a t t e r has been t a k e n a s 7 per cent of t h e wood oil, t h a t a m o u n t having been shown t o be a n average for a number of determinations o n supposedly pure wood oil. I t is possible t o get a n estimation of t h e a m o u n t of wood oil present b y t h e direct weighing of t h e precipitated m a t t e r . I n t h a t case great care must be exercised t o prevent oxidation of t h i s material during drying. T h e t a b u l a t e d results show t h e possibilities of this method as a means oE detecting adulteration in wood oil. It is certain t h a t further refinement of t h e m e t h o d is possible, which will a d d t o i t s accuracy. 1

Chem C e n t r b l , 83 (1912). 2154.

1-01. 6 , No.

IO

INSOLrBLE SOAP

I n studying t h e characteristics of this solid precipitated glyceride, it was noted t h a t t h e potassium soap was b u t slightly soluble in _absolute alcohol, which agrees with t h e findings of Normann’ a n d Morrell’ who worked on t h e material precipitated b y s u n light alone. Norrell, however, also states t h a t t h e soap is practically insoluble in water, which s t a t e m e n t is not borne o u t b y t h e experience of t h e authors. T h e comparative insolubility of t h e potassium soap of Chinese wood oil offers possibilities of a rapid method for t h e detection of adulteration i n wood-oil samples. T h e saponified product separates quite completely from absolute alcoholic p o t a s h , a n d m a y be washed free from t h e soap of t h e adulterating material. If t h e method be carried o u t a t uniform t e m p e r a t u r e , preferably o o C., a n d t h e alcohol for washing t h e precipitate b e previously s a t u r a t e d with t h e s o a p , it is possible t o estimate t h e a m o u n t of adulteration within fairly narrow limits. A K A L T T I C A L N E T H O D s o . 2--A 3-8. sample of t h e oil t o be examined is saponified with I O O cc. of N / 4 absolute alcoholic potash for one-half hour, using a n air condenser of sufficient length t o prevent t h e loss of alcohol. T h e saponified mixture is cooled t o o o C., held for I O minutes a t t h a t t e m p e r a t u r e , a n d filtered through a Gooch crucible using a filter-paper disk instead of a n asbestos p a d . T h e precipitate, after washing thoroughly with ice-cold s a t u r a t e d absolute alcohol, is removed from t h e crucible t o a cover glass, a n d is dried a t 7 j t o 80’ C., under v a c u u m , a n d with a s t r e a m of d r y hydrogen or carbon dioxide passing through t h e desiccator. After cooling without removing from t h e desiccator, t h e precipitate is t a k e n out a n d weighed, a n d t h e weight calculated t o wood oil. I t is necessary, if t h e m e t h o d is t o be a t all accurate, t o use absolute alcohol b o t h for saponification a n d for washing t h e precipitate, a s t h e soap is appreciably soluble i n t h e presence of even small a m o u n t s of water. This alcohol a n d alcoholic potash should be freshly s a t u r a t e d with t h e soap before use, for although t h e soap is b u t slightly soluble i n absolute alcohol, t h a t solubility changes on s t a n d i n g , especially if exposed t o light. I t is a comparatively easy m a t t e r t o keep freshly s a t u r a t e d solutions ready for use b y making up a batch of t h e soap a n d introducing it i n t o t h e stock bottles of alcohol a n d alcoholic potash, i n quantities more t h a n sufficient t o s a t u r a t e t h e m a t o o C. When a b o u t t o make a determination, t h e solution m a y be warmed until an appreciable a m o u n t of soap goes i n t o solution, after which i t m a y be cooled t o o o C. a n d held for I O minutes a n d filtered. This fresh filtrate is ready for use, a n d t h e fact th:tt t h e procedure followed will be duplicated on t h e saponified sample helps t o insure t h e accuracy of t h e determination. During t h e washing ‘of t h e precipitate t h e whole must be k e p t cold, f o r t h e solubility of t h e material i n alcohol is greatly increased b y a rise in t e m p e r a t u r e . This is accomplished b y filtering through a Gooch crucible surrounded by cracked ice. T h e authors 1

2

Chem. Ztg., 31 (1907). 188. Trans. Chem. Soc., 101 (1912). 2082.

Oct., 1914

T H E J O r R A V A L O F I N D L-STRI.1 L A R D E A V G I N E . E R I S G C H E M I S T R Y

ha\-e found the a p p a r a t u s shown in Fig. I t o be quite satisfactory. T h e precipitate is susceptible t o oxidation a n d must be kept a w a y from air during drying. Also,'the fact t h a t high temperature will char t h e soap limits t h e drying temperature t o about 80' C. T h e precipitate m a y be dried in a desiccator connected b y a long rubber tubing t o a source of hydrogen or carbon dioxide, and t o a vacuum p u m p . After introducing t h e precipitate t o be dried, t h e desiccator m a y be placed in a low-temperature s t e a m drying oven for 3 hours. T h e results obtained b y t h e use of t h e insoluble-soap method a n d t h e d a t a from which these results were computed, are compiled in Table 11. I n calculating t h e results for this table it was decided t o accept t h e weight of t h e dried insoluble soap a s representative of t h e weight of wood oil present in t h e sample, since the FIG I error of this assumption was considered t o be within t h e limits of error 0; t h e method. Although neither of t h e above methods has proved entirely satisfactory a s a method for t h e estimation of wood oil in rosin varnishes. t h e efforts made t o apply t h e m t o t h a t end have resulted in some interesting d a t a regarding t h e conditions existing in this t y p e of varnish. TABLE 11-Ex

PRECIPITATIOV OF INSOLUBLE POTASSIUM SOAP U r 0 O D OIL 7 ADULTERANT CalReSAMPLE ADULTERANT cu- covFound c--Soap lated ered Present Xo G G Kind G G C 7 , G 7 7c 1 3.301 3 . 3 3 4 3 . 3 3 4 101.0 -0,033 -1.0 12.8140'304) 2.807 2 , 8 0 7 9 9 . 8 0.311 9.9 4:s 1 3 . 0 1 2 0 . 1 8 0 Linseed 3.021 3 . 0 2 1 1 0 0 . 3 0.171 5.5 5.6 1 2.516 0 . 5 0 6 ( 2.508 2 , 5 0 8 9 9 . 8 0.514 17.0 16.7 1 3 138 .... 3 , 1 7 0 3 , 1 7 0 1 0 1 . 0 -0.032 -1 0 1 2:859 0 : 9 5 9 Soya 2.874 2.874 100.6 0.944 24.7 2 3 : 8 1 2.6420.881)bean 2 . 6 4 5 2.645 100.1 0.878 24.9 2 5 . 0 1 3.013 . . . . .... 3.006 3 , 0 0 6 99.8 0,007 0.2 1 3 , 0 0 6 0 , 1 6 7 Soya 2 . 9 8 2 2.982 9 9 . 2 0.191 6.0 5:3 1 7 . 0 5 1 1 . 3 0 2 1 bean 2.020 2.020 98.1 1.333 39.8 38.9 1 2.461 0 . 1 2 5 , 2 . 5 3 6 2.536 1 0 3 . 0 -0.075 2.9 4.8 1 2 . 7 9 1 0 . 6 0 7 ~2.883 ~ ~2.E(83 ~ ~1 0 3~. 3 ~ 0~. 5 1 5 15.2 1 7 . 9 1 2.742 0 380 2.761 2 . 1 6 1 100.7 0.361 11.5 12.2 1 2.742 0 183; 2.741 2.741 1 0 0 . 0 0.184 6.3 6.3 1 2.528 . . . .., . 2 . 5 0 1 2.501 9 8 . 9 0,027 1.1 .. 1 2.524 ... .... 2 , 5 5 0 2 . 5 5 0 101.0 -0,026 -1.0 .. 1 2.521 . . . .... 2 . 5 1 0 2.510 9 9 . 5 0.011 0.5 1 2.510 2.514 2.514 1 0 0 . 2 -0.004 -0.2 12.3210:iOil 2.367 2.367 102.0 0.661 2 1 . 8 22:4 1 2 . 4 2 8 0 738jLinseed 2 . 5 0 8 2 . 5 0 8 103.3 0.658 20.8 23.3 1 3.019 ,... 3 . 0 1 9 3 . 0 1 9 100.0 I 3.039 o : ~ O Y Mixed 3.025 3.025 99.5 0:4i3 12:3 i i : 9 1 3.199 1.049) .3.201 3 . 2 0 1 100.3 1.038 2 4 . 5 2 4 . 7 2 3.252 . . .. .. 3.224 3.224 99.1 0.028 0.9 .. 3 3.471 . . .... 5 . 5 4 4 3 . 5 4 4 1 0 2 . 1 -0.073 -2.1 .. 4 3.1.56 . . .,, 3 , 0 1 4 3.014 95.5 0,142 4.5 ., 4 3.190 . . . . ,,. 3,092 3.092 96.9 0.098 3.1 .. NuTE-XVood oils Nos. 1 2 a n d 3 were t h e same a s those in Table I . Wood oil No. 4 was furnished'by M r . L. P. Nemzek representing t h e Educational Bureau of t h e Paint Manufacturers' Association. This oil is f r o m American-grown n u t s , %MITATION B Y

809

A comparison of t h e molecular weights of t h e f a t t y acids from raw wood oil a n d t h e light breaks seems t o show t h a t this light break is a n isomer rather t h a n a polymer, a n d t h a t there is practically no difference between t h e light break formed slowly b y sunlight alone a n d t h a t catalyzed b y iodine. USIVERSITY OF ICZICHIGAW ANN ARBOR ~

OILS OF THE CONIFERAE. 11-THE LEAF AND TWIG, AND BARK OILS OF WHITE FIR By A . \V. SCHORGER

Received August 15. 1914

T h e white fir [ A b i e s concolor (Gord.) P a r r y J is found on t h e mountain slopes from southern Oregon t o Lower California and from Nevada, U t a h , a n d southern Colorado through Arizona and New Mexico. T h e dense crown consists of short, heavily foliaged branches. T h e leaves a t t h e t o p of t h e tree are usually I t o I l i g inches in length, while those of t h e lower branches are somewhat longer-1 ljg t o 3 inches. L E A F A X D TTVIG O I L S

T h e oils were greenish yellow in color with a green fluorescence with t h e exception of samples Nos. 2439 a n d 2487, which were lemon-yellow in color and showed no fluorescence. The residue left after removal of t h e terpenes b y distillation was fluorescent t o a marked degree, b u t this property was n o t noted in t h e "green oil" fraction obtained, though the oil owes its green color t o this fraction. T h e properties of t h e oils and the yields are given in Table I. TABLEI-PROPERTIES

7 m

7

Sample No. dijo

n

2176 2180 2181 2183 2439 2440 2487

1.4788 1.4786 1.4786 1.4796 1.4787 1.4790 1.4781

~

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0 8758 0.8738 0.8732 0.8737 0.8720 0.8745 0.8777

OF OILS Ester No. AcePer cent Yield of oil aftet t a t e alcohol Acid Ester acetyl- Per -APer --~e~~~~ ~ o KO. S o . ation cent Free Total cent LEAF A N D TWIGOILS -27.94 1.13 12.52 48.88 4.38 10.28 13.73 0.140 -20.18 1.81 27.34 54.58 9.57 7.65 15.17 0.029 -21.65 1.43 24.03 52.45 $41 7.99 14.60 0.050 -26.87 1.07 20.55 54.22 t.19 9.50 15.15 0.150 -26.59 1.01 14.48 51.83 5.07 10.57 14.55 0.163 -24.08 1.32 14.80 47.84 5.18 9.32 13.39 0.095 -20.11 1.06 18.79 55.51 6.58 10.39 15.56 0.272

_______

Mean, 6.63 9.39

14.59 0.128

BARK OILS OLDiOo

2209 0.8i67 1.4833 -20.95 2423 0.8702 1.4809 -20.15

1.22 0.87

6.88 23.34 2.41 6.43 20.45 2.25 ~

Mean, 2.33

4.58 3.90

6.48 0.07 5.67 0.12

4.24

6.08 0.095

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An examination of t h e separated constituents of a Chinese-wood-oil rosin varnish seems t o show t h a t t h e polymerization of wood oil in t h e presence of rosin is practically a s complete as in t h e oil, subject t o t h e same heat t r e a t m e n t in t h e absence of rosin. T h e f a t t y acid in each case shows a molecular weight double t h a t of t h e f a t t y acid of r a w wood oil. T h e difference in characteristics between these t w o polymerized products h a s not a s yet been satisfactorily accounted for.

There is a considerable variation in t h e ester a n d free alcohol content in t h e various samples b u t t h e t o t a l alcohol content is fairly uniform. Samples Nos. 2439 a n d 2440 were distilled from material taken from t h e top a n d base, respectively, of t h e same tree. T h e needles from t h e t o p of t h e tree show a slightly greater total alcohol content. Six hundred grams of oil distilled as follows: 1611 6 j o , 1 j . j per cent: 16j-1joo1 4 2 per cent; 1 7 0 - 1 8 0 ° , 1 8 . j per c e n t ; 18*19j", 3 per cent; 1 g j - - 2 4 0 ~ , 1 3 per c e n t ; z40-310", 3 per cent. IDENTIPICATIOS O F CONSTITUEKTS

FURFURAL-The first fraction was shaken out with water. On treating t h e aqueous extract with aniline and hydrochloric acid a deep crimson color characteristic of furfural was obtained. a-PISEh?z-The fraction examined for a-pinene h a d