I N D U S T R I A L A N D ENGINEERING CHEMISTRY
March, 1927
Magnesia M i x t u r e
Another possible Source of error is the use of the present magnesia mixture. E~~~~chemist who has kept the official solution for weeks a t a time in a stock bottle is familiar with the visible attack on the walls of the bottle, particles from which apparently flake off and settle to the bottom, This action is doubtless due to the presence of strong ammonia. By delaying the addition of the ammonia solution until shortly before the mixture is to be used, this action can be prevented. It is possible that such action may be the source of the silica sometimes reported to be found in magnesium pyrophosphate after ignition. To avoid this error, the following modification of the official method of making and using this solution is suggested:
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Dissolve 22 grams of recently ignited calcined magnesia in dilute hvdrochloric acid. avoiding. an excess of the acid. Add a little*calcined magnesia in excess and boil a few minutes to precipitate iron, alumina, and phosphoric acid. Filter into a 2-liter flask. Add hydrochloric acid dropwise, using methyl as indicator, until the solution just reacts acid, then add i ml. of 1:1 hydrochloric acid. Add 280 grams of ammonium chloride, make t o mark, and filter into the stock bottle. From this solution any small quantity of magnesia mixture may be quickly and easily made. If 100 ml. are desired, take 50 ml. of the stock solution, add t o it 13 ml. of ammonia (sp. gr. 0.90) and make up to 100 ml. Filter just before using. Ten milliliters of this solution are ample for each decigram of p205.
Of course, instead of the ignited magnesia, the equivalent quantity of magnesium chloride crystals, as given in the official methods, may be used.
Some Constituents of Spanish Moss' By A. W. Schorger
c. F. BURGESS LABORATORIES, hf.4DISON,
WIS.
T h e expansion of the a u t o m o b i l e i n d u s t r y has necesHydrolysis of the cellulose PAKISH moss (Tillands i t a t e d the use o f g r e a t q u a n t i t i e s of stuffing materials with dilute sulfuric acid unsia usneoides) is found in t h e upholstery. F r o m t h e s t a n d p o i n t of suitability, der pressure gave glucosamainly in the coastal S p a n i s h m o s s r a n k s next to t h e b e s t grades of h a i r for zone, m. p. 205-6" C. region of the southern states. the f u r n i t u r e trade. It is a true epiphyte-i. e., Galactan In m o s t cases t h e retting of the m o s s is conducted in a its food is derived entirely very h a p h a z a r d f a s h i o n so t h a t t h e highest q u a l i t y of The amount of galactan from the air. Though growfinished p r o d u c t is f r e q u e n t l y n o t a t t a i n e d . The r e t ing usually on trees, i t is not present could not be accut i n g period m a y vary f r o m six weeks to six m o n t h s . uncommon to find it in the rately determined, but it is The p r e s e n t investigation of t h e composition of the live state on telephone wires. less than one per cent. Mucic moss has been m a d e t o s e c u r e an intelligible basis for Propagation takes place from acid was not obtained by s t u d y i n g t h e r e t t i n g process. strands torn loose and carried direct oxidation of the moss. by the mind, growth taking When 50 grams of mow QS were place wherever suitable lodgment is found. It is very tena- heated with water under pressure, the extract evaporated to dryness, and carefully oxidized with 25 per cent nitric acid, cious of life and able t o resist prolonged drought. Under the microscope the moss is observed to be covered mucic acid, m. p. 213' C., was obtained. The source of the with minute leaf scales. There is a dark-brown central mucic acid is galactose rather than galacturonic acid, for the "hair" of considerable strength surrounded by a pulpy cortex. following reason: The sirup obtained by hydrolyzing the The hair shows longitudinal striations and consists of minute moss with dilute sulfuric acid a t atmospheric pressure 011 fibers cemented together by a reddish brown substance. heating with methylphenylhydrazine gave galactose methylThe method of collecting and retting the moss to produce phenylhydrazone. The purified crystals melted a t 180' C. a product suitable for upholstery has been described by This derivative was obtained from the retted moss also, though Record.'#* From the botanical side the moss has been in less quantity. thoroughly described and figured by Billings.2 Aside from a Analysis of MOSS5 study of the ash3p4j5and the suitability of the moss for a stock (Based on oven-dry material, drying temperature 105" C ) food,5 its chemical composition has received little attention. ENTIRE RETTED MCJSS LfOSS The nitrogen content is high. Halligan5 reported 12.07 per P e r cent P e r cent cent protein (1.93 per cent nitrogen), while Pickell found 5.07 Ash 5.51 0.54 per cent protein and 3.92 per cent true albuminoids. This Nitrogen 1.11 0.80 Solubility in: paper is devoted primarily to the carbohydrate constituents. Ether2.21 0.60
S
Cellulose
If the moss, especially the hair, is heated with dilute nitric acid or sodium hydroxide, there is obtained a mass of short, slender fibers with pointed ends. These fibers vary in length from 0.25 to 0.90 mm., the average being 0.63 mm. The cellulose was determined by chlorination followed by treatment with hot 1 per cent sodium hydroxide. The chlorinated products mere slowly removable with a 0.5 per cent solution of sodium hydroxide, and scarcely affected by a 2 per cent solution of sodium sulfite. The cellulose so isolated consisted of fibers and leaf scales, both of which were stained blue by zinc chloriodine reagent. 1
Received October 16, 1926.
* Figures refer t o bibliography
a t the end of article.
Alcohol (following extraction with ether) Glycerol at 200° C. for 30 minutes Sodium hydroxide 1 per cent hot Sodium hydroxide: 0.25 per cent, cold Water, hot Water, a t 50 Ibs. pressure for 30 minutes Pentosans Non-carbohydrates Methoxyl Cellulose Pentosans in cellulose a Figures are averages of two determinations.
9.08 26.7.5 4 s . 23 26.54 17.04 35.53 15.68 16.63 1.86 46.78
...
6.54 4 9 : 35
...
...
18: i 3 19.51 3.03 37. X i 16.52
Pentosans
The pentosans present consist of araban with a small amount of xylan. X o methylpentosans were found. The identifications were made with a sirup obtained by hydrolyzing the moss with 2.5 per cent sulfuric acid a t atmospheric pressure and purifying in the usual way. When the sirup
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IYDUSTRIAL A.VD ENGINEERING CHEMISTRY
was heated with diphenylhydrazine in alcoholic solution, arabinose diphenylhydrazone, m. p. 203-4" C., was readily obtained. A satisfactory test for xylose could not be obtained with this sirup. The following procedure led to its identification: The moss was exhausted with methanol and extracted with cold 5 per cent sodium hydroxide for 48 hours. After washing with mater, the undissolved residue was hydrolyzed by boiling with dilute sulfuric acid. A portion of the resulting sirup that was soluble in 95 per cent alcohol was submitted to Bertrand's cadmium xylonate test. The solution was allowed to evaporate to dryness a t room temperature. The residue was rapidly triturated a i t h a small amount of water, the aqueous solution decanted, and the white crystalline residue brought into solution by warming with a little water. The latter solution on standing gave numerous, characteristic boat-shaped crystals of cadmium xylonate. I n addition to galactose, arabinose, and xylose, the sirup obtained by hydrolysis with dilute acid a t atmospheric pressure contained glucose, the probable source of which is discussed below-. Mannose and fructose %yerenot found. Attempts to isolate a hemicellulose of high purity failed owing t o the presence of a substance forming a very dark solution with sodium hydroxide. The moss was first exhausted in a Soxhlet extractor with methanol. The coloring matter was only partially removed by repeated extraction with 2 per cent ammonia in the cold. When the residue ivm treated with 5 per cent sodium hydroxide the extract appeared as dark as from the raw moss. The best method found for removing the coloring matter mas tine use of 0.25 per cent sodium hydroxide, though the moss lost 25 per cent in weight by the treatment. Portions of 50 grams of the comminuted, alcohol-extracted moss were treated with 2 liters of 0.25 per cent sodium hydroxide, and allowed to stand with frequent shaking for 48 hours. The liquor was filtered off and the process repeated. Before the final filtration, the moss and alkali were ground in a ball mill for an hour. The moss was then filtered off and washed exhaustively with cold water. The nearly colorless residue was treated with sufficient sodium hydroxide to make a liter of 5 per cent alkali and allowed to stand with frequent shaking for 48 hours. The alkaline filtrate, still quite highly colored, was treated with a n equal volume of alcohol. The dark flocculent precipitate was filtered off, dissolved in 400 cc. of 5 per cent sodium hydroxide, and 300 cc. of Fehling's solution were added. The voluminous gelatinous precipitate was treated in the usual way.6 The hemicellulose was redissolved in alkali and again precipitated with Fehling's solution. I n spite of all the purification, the hemicellulose was dark, greenish gray in the dry state. It contained 73.47 per cent pentosan calculated as araban. Pectin
S o conclusive evidence of the presence of pectin could be obtained. Characteristic of pectin is the formation of methanol when heated with dilute sodium hydroxide. This test conducted according to von Fellenberg' was negative. An extract of the moss with hot 0.5 per cent oxalic acid,8 in which pectin is soluble, gave a greenish gray precipitate. This precipitate did not dissolve in boiling mater or gelatinize on cooling, nor did it gelatinize when treated with 10 per cent sodium hydroxide solution and allowed to stand 48 hours. Judging from the behavior of this substance in comparison with pectin prepared from the rind of grapefruit, the moss does not contain pectin. Glucoside
The moss appears to contain a glucoside soluble in hot water and alcohol. It is very sensitive to heat and alkalies
Vol. 19, N o . 3
and has so far resisted all attempts a t crystallization. After extraction with benzene to remove chlorophyl and wax, the finely comminuted mass was extracted with hot water. The filtrate foamed too badIy t o be concentrated in vucuo, so it was evaporated on the steam bath. The residue was almost insoluble in alcohol and acetone, but almost completely soluble in hot glacial acetic acid. The mater extract gave a voluminous precipitate with lead acetate but none with gelatin. Hydrolysis with dilute sulfuric acid gave a sirup, most of which was insoluble in alcohol. The soluble portion gave glucosazone, m. p. 204" C. During the hydrolysis there separated a brown substance resembling phlobaphene or tannin anhydride. It contained 3.02 per cent methoxyl. Tests for hydrocyanic acid in the crude moss were negative. The moss, previously extracted with benzene, was extracted with hot methanol in a Soxhlet apparatus. The extract n-ould not crystallize and was only slightly soluble in water. Prolonged extraction caused a black tar-like mass to separate from the methanol. Evaporation of the methanol extract gave a similar product. Hydrolysis of 10 grams of the black residue gave 3 grams of a sirup soluble in ethyl alcohol. A portion of the sirup on distillation with 12 per cent hydrochloric acid gave 2.98 per cent furfural. Another portion of the sirup, on heating with phenylhydrazine, gave glucosazone, m. p. 2M-5" C. The water extract of the moss reduced Fehling's solution strongly. Emulsin added to the extract did not increase its reducing action. The raw material for this investigation consisted of moss that had been collected green and allowed t o air-dry. Evidence points to the presence of an enzyme which causes partial hydrolysis of the glucoside as the plant dies. Fresh, green material should be more promising for isolating a glucoside. A marked property of the moss is the ease with which i t disintegrates in the presence of even very dilute solutions of the caustic alkalies. The solutions rapidly acquire a deep, brownish black color. When left in 0.25 per cent sodium hydroxide for a few days, the moss appears gelatinous, almost colorless, and can be easily reduced to a pulp between the fingers. Only a small amount of tannin is present. A solution obtained by boiling the moss with water gave a faint greenblack color with ferric chloride, a copious yellow precipitate with limewater, and a slight yellow precipitate with bromine water. The raw moss, previously extracted with alcohol and ether, gave a black residue of 16.63 per cent when treated with 72 per cent sulfuric acid in the usual way for determining lignin; without the preliminary extraction, 18.14 per cent (corrected for ash). Seither this residue nor the raw moss, when chlorinated and then treated with sodium sulfite solution, gave the characteristic lignin color reaction. The black product obtained by extracting the retted moss with 3 per cent ammonia, when fused with potash, yielded yellowish crystals in too slight amount to be identified. When these were dissolved in water and ferric chloride solution was added, a greenish blue color changing to crimson on the addition of sodium carbonate was obtained. The black solution obtained with sodium hydroxide and other data point to the presence of a glucoside of a phenol methylether. Clark9 found that the blackening of the leaves of the wild indigo was due to a phenol originally present as a glucoside. Ether and Alcohol Extracts
The moss was extracted first with ether, then with alcohol, for 6 hours each. The ether extract was a soft, yellowish mass with a characteristic odor. The alcohol extract was dark brown, hard, and like varnish.
IYDUSTRIAL A 3 D ENGINEERING CHEXISTRY
March, 1 9 2 i
The moss contains considerable quantities of a wax. -4 concentrated hot benzene extract of the moss sets t o a gel on cooling. The wax is sparingly soluble in petroleum ether,
but readily soluble in chloroform. An alcoholic extract of the wax isolated with benzene gave a distinct sterol reaction with digitonin. The petroleum ether extract of the moss was yellolv. On pouring this extract t'hrough a column of dry, precipitated calcium carbonate, there was obtained an upper preen ring (chlorophyl) and a lower pink one (carotinoid pigment). The n-ax deposited from all solvents as a gel. The best method of purification found consisted in pouring the chloroform solution into a hot solution of absolute metjhanol, in which the wax is sparingly soluble. The wax retained a greenish yellow color after repeated purification. The saponification number v a s 41.24. Saponification with alcoholic potash gare an alcohol melting a t 79-80' C. and solidifying :it 78-79" C. Ash
It will be noted that the moss is high in ash. TTherry and Buchanan'" consider the presence of silicon and iron a mystery. This is readily explainable in t'hat' practically all
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the inorganic matter is derived from dust transported by the wind and rain, and caught by the leaf scales which are admirably adapted to this purpose. This view is supported by the fact that the entire moss contains 6.61 per cent of ash and the hair only 0.54 per cent. Summary
Spanish moss contains galactan, araban! xylan, and cellulose, and what appears t'o be a phenol methylether glucoside. Among the non-carbohydrate constituents are protein, chlorophyl, a carotinoid pigment, a sterol, and wax. Bibliography 1-Record, Sei. .I m . 1916, 2s. P--Billings, Botan. Guz., 38, 99 (1904) 3-Pickell, Florida Expt. Sta., Buil. 11 (18901; 12 ( l b 9 1 ) . 4-Luca, C o m p t . r e n d . , 53, 241 (1861). .j-Halligan, J . I n d . En!. Ciiem., 1, 206 (1909). 6-Baker and Pope, J . Chem. Soc. ( L o n d o n ) , 77, 699 (1900). i-Von Fel!enherg, Biochem. Z.,85, 68 (1916). 8-Farnell, I n t e u n . S U ~ W J . , 25, 248 (1923). 9-Clark, J , B i d . C k e m , 21, 645 (1919). lO--\Therry and Buchanan, .Science, 61, X I V (19251. 11-Marsden, C . S . P a t e n t 1,327,873 (1920).
Anhydrous Barium Perchlorate and Mixed AlkalineEarth Metal Perchlorates as Dehydrating Reagents' By G. Frederick Smith U R B A N AILL. ,
The increasing use of chemical reactions employing Requirements of a Drying HE p r o n o u n c e d staAgent bility of the alkalinegases under pressure involves as well the need for their earth metal perchloefficient dehydration. The qualities desirable i n a The most important rerate, both a t comparatively drying agent f o r both commercial and experimental quirements to be fulfilled by elevated temperatures and in use have been Summarized. Chief of these desired a drying agent are as follows: properties are a high efficiency and capacity, possibility tile p r e s e n c e of reducing agents unsaturated of preparation, and regeneration without fusion, mod1-Its drying efficiency, or the degree of thoroughness hydrocarbons, carboil moncrate Cost, and general applicability. The use-of a with which it removes moismixture of two dehydrating agents, each of which S U P ture from d i f f e r e n t g a s e s oxide, and hydrogen, together brought into contact with it, Tvith their excessive deliquesplies desirable properties which are deficient i n the be very high. A list Of cence Jvhen in the anhydrous other, has been shown to solve the difficulties in the desiccating agents, t o g e t h e r condition, iiiakes their use a j Particular case of mixtures of anhydrous barium Perwith their classification as to chlorate as the main constituent with anhydrous magdehydrating efficiency, has been dehjrdrating reagents .i-ery atnesium perchlorate as the minor component. reported by Baxter and coltractiTe, both experiment,all\labor at or^.^ Phosphorus pentand industrially. o x i d e h a s b e e n shown by A study of the preparation and propert,ies of magnesium hhrley6 to be capable of d r r i w air, hydrogen, and oxygen t o a high degree of efficiency, that the residual moisture in perchlorate as the trihydrate and the anhydrous to de- such comparatively unlimited volumes of these gases after contact termine their efficiency and capacity as drying agents, was Jvith this desiccant is unweighable, Anhydrous magnesium made by TVillard and h more detailed etudy of the perchlorate, as well as its trihydrate, has been demonstrated?z3 trihydrate of magnesium perchlorate and its use as a drying to be of efficiency equal to that of phosphorus pentoside a t agent in steel and organic conibustio~~ analyses for carbon moderate rates Of gas flow-. 2--The drying capacity, or the weight of moisture absorbed and hydrogen !vas carried out, by the >\*rite*alld collaboraper unit weight of desiccating material, should be relatively tors.3 (This reagent is nom being distributed und1.r the trade high, For phosphorus pentoxide the drying capacity is very llallle "Debdrite.") -1bibliography of the stlldy of the small. This is still more pronounced because of the physical alkaline-earth metal as well as the alkali metal perchlorates characteristics of the reaction products formed. For other up to a recent date has been previously publishetl.4 desiccants having higher drying capacity the well-spent reagent often acquires physical characteristics resulting in clogging The present work consists in the demonstration of the of drying towers and tubes, Inany ad\-antages t o be deriT-ed from the use of variously original 3--It should be easy to restore the drying prepared mixtures of anhydrous barium and magnesium drying capacity and efficiency. Such regeneration would be much more satisfactory if it could be accomplished without perchlorates as desiccating materials.
T
Received October 22, 1926. J . A m . Chem. Soc., 44, 2255 (1922). Smith, Brown, a n d Ross, THISJ O U R K A L , 16, 20 (1924). \T'illard and Smith, .I. .Am. Chem. Soc., 46, 286 (1923).
5 Baxter and Warren, J . A m . Chem. SOC.,33, 340 (1911); Starkweather, I b i d . , 38,2038 (1916). 6 Ibid., 86, 1171 (1904).
Baxter and
