ter Meulen Method for Direct Determination of ... - ACS Publications

W. WALKER RUSSELL AND MAURICE E. MARKS, Metcalf Laboratory, Brown University, Providence, R. I. T HAS been shown recently (3) that when certain ...
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September 15,1934

INDUSTRIAL AND ENGINEERING CHEMISTRY

no longer translucent but is opaque. Even when a longer period is required, the time?-consumed is not considered excessive. Unless fine suspended matter is present in the oil in the paper, the sample obtained by the method is clear and free from sediment. The use of the filtering cone is recommended for straining out cable wax or bits of torn paper. Paper fibers do not seem to be dislodged during centrifugalizing. Not only is the method satisfactory for ordinary samples, but it has also been found to be applicable to samples containing abnormally low quantities of very viscous oils. Since the oil is deposited in a small weighing vial, it can be weighed for test and used without loss. As has been intimated, one of the reasons the device was designed was to obtain oil for viscosity tests. That the vis-

381

cosity of the oil taken from radial samples of aged cable varies was observed in the investigations in this company. The possible significance of this phenomenon as regards electric transmission cable life in service is reported in the literature (8). LITERATURE CITED (1) $endall, ,James, and Monroe, K. P., J. Am. Chem. SOC.,39, 1787

(1917). ( 2 ) Shanklin, G . B., and McKaye, G. M. J., Trans., Am. Inst, Elec. Engrs., 48, 338 (1929). (3) W y a t t , K. S. Ibid., 52, 1025 (1933). (4) W y a t t , K. S., Spring, E. W., and Fellows, C H., Ibid., 52, 1035

(1933). RECEIVED May 14, 1934. This work forms part of a general research on the deterioration of high tenaion underground cable being undertaken by The Detroit Edison Company

ter Meulen Method for Direct Determination of Oxygen in Organic Compounds Containing Nitrogen W. WALKERRUSSELLAND MAURICE E. MARKS,Metcalf Laboratory, Brown University, Providence, R. I.

I

T HAS been shown recently (3) that when certain modi- monia from the system. A relatively large amount of catafications are employed, the ter Meulen method for the lyst-5 to 10 grams-is desirable to prevent the appearance of direct determination of oxygen in organic combination oxides of carbon in the effluent gases to be absorbed by the yields very satisfactory results in the case of compounds sodium hydroxide. Such an amount of active catalyst gives containing carbon, hydrogen, and oxygen. By using a very persistent blanks. Thus the blank per half hour may be as active, thoria-promoted nickel catalyst, all the oxygen in the high as 2 mg. with a freshly prepared catalyst. The initial organic compound was converted to water which was com- blank gradually decreases with continued use of the catalyst pletely retained by the first calcium chloride tube of the ab- to a few tenths of a milligram, owing to the slow reduction sorption train, since no oxides of carbon escaped methana- of the last traces of nickel oxide. Therefore, the values of tion. Under such conditions the analysis of organic com- these blanks must be carefully ascertained and used to corpounds also containing nitrogen should yield hydrogen, rect the results obtained. In case there is a difference behydrocarbons, nitrogen, water, and ammonia. Since calcium tween the blanks determined before and after an analysis, chloride absorbs ammonia to a certain extent, ter Meulen the average blank is best employed. (1) has proposed the use of a special tube carrying a charge of standard acid and in a second compartment calcium chloride. TABLEI. RESULTS OF ANALYSESBY MODIFIEDTER MEULEN METHOD Any ammonia evolved during analysis is retained by the acid TEMPERAwhich is back-titrated a t the end of the run. Thus the gain NITROWEIGHT TURE OF --OXYOENQEN CONin weight of the tube due to ammonia can be evaluated and OF CATACalm- VERTED SUBSTANCE SAMPLE LYST Found lated TONHX the water absorbed ascertained by difference. It appeared Gram ' C. % % % to the authors that in the absence of oxides of carbon in the Acetamide 0.20685 350 27.14 27.10 85 0.1910 350 27.14 58 effluent gases, procedure might be considerably simplified if an efficient water absorbent could be found which would not Dimethylglyoxime 0.18615 350 27.50 27.57 45 0.2117 350 27.61 53 absorb ammonia. Reagent-grade sodium hydroxide in pellet form proved to meet these requirements. Pellets Urea 0.1939 300 26.59 26.65 33 0.1497 350 26.71 are to be preferred to a more finely divided form because 3,5-Dinitrobenzoic acid 0.1596 350 45.11 45.27 60 they offer little chance for mechanical retention of ammonia. 0.2010 350 45.22 APPARATUS AND METHOD The apparatus previously described elsewhere (3) can be used without modification other than the replacement of all calcium chloride and ascarite with pellets of reagent-grade sodium hydroxide. A 5-inch (12.5-em.) Schwartz tube charged with this sodium hydroxide served to retain completely the water corresponding to the oxygen in the sample. A second and third tube similarly charged, t o act as guard tubes, complete the absorption train. The method of analysis is identical with that already described (S), except that for compounds containing much nitrogen the time for an analysis may well be extended to 1.25 or 1.5 hours, in order to allow ample time for sweeping am-

p-Nitroacetanilide

0,20745 0.1946

350 350

26.70 26.88

26.66

58

p-Nitrobenzeneazoresorcinol

0,2295 0.2337

350 350

24.53 24.61

24.70

54

RESULTB The results of analyses made upon high-grade organic chemicals containing nitrogen, with sodium hydroxide employed as absorbent, are given in Table I. In addition to the oxygen content found, the percentage of the calculated nitrogen appearing in the exit gases as ammonia is also given. Although over 50 per cent of the nitrogen frequently appears as ammonia, it is improbable that a simultaneous de-

Vol. 6, No. 5

A N A L Y T I C A L EDITION

382

termination of oxygen and nitrogen (as ammonia) can be arranged because of the activity of the cracking surface in liberating nitrogen in difficultly reducible form, probably m free nitrogen, from the compounds studied. More stable nitrogenous compounds may prove an exception, since Smith and West (4), who have obtained excellent results in the nitrogen analysis of organic compounds containing nitrogen in the ring, and also of nitrogen derivatives of chaulmoogric acid by catalytic hydrogenation ( g ) , have found it desirable to preheat strongly the gases evolved from the

heated sample before passing them over the nickel catalyst. It is proposed t o study this situation further,

LITERATURE CITED (1) Meden, H.ter, Rec. truv. chim., 43, 899-904 (1924). (2) Meulen, H. ter, and Heslinga, J e t “Nouvellea MBthodes d’Andyse Chimique Organique,” pp. 22-31, Dunod, Paris, 1932. (3) Russell, w. w., and Fulton, J. w., IND. ENQ.CREM.,Anal. Ed., 5,384 (1933). (4) Smith, F. L.8 and West, A. p-3 Philippine J . Sei., 31, 265-73 (1926). RECEIVED July 16, 1934.

Identification of Common Glycosides KIRBYE. JACKSONAND WILLIAMM. DE”,

W

HEREAS many individual tests for the glycosides are

found in the literature, hitherto they have not been applied to all glycosides and no systematic method for their identification has been available. The authors have found that known reactions, modifications of known reactions, and new color reactions with simple reagents will enable one to identify the more common glycosides. The glycosides in Table I are best identified in the order

University of Washington, Seattle, Wash. given. (Picrotoxin, a compound closely related to the glycosides, is included in this study.) In all cases a few milligrams of each are treated at room temperature for about 2 hours with the reagents shown in Table 11, so that effects of all reagents used on these glycosides are now determined and disclosed. (For various confirmatory tests, see especially Merck’s Reagenzien Verzeichnis, 1924.)

TABLEI. IDENTIFICATIONS a

Phlorhizin Arbutin, Digitonin Picrotoxin Colocynthin Soillit oxin Amygdalin Salicin Strophanthin Digitalin Convrtllarin Savonin sapotoxin Convallamsrin Absinthin B1 = blue Bk black Br = brown Small letters =

-

b

c

d

e

Br Br Y Y Cr brBk dkG brR brBk Blood R dkBr Br Br brY

-

Ca = carmine Cr = crimson Ch = cherry lighter shades: dk

f Y Y Br Y rBr Br

Ca

8’

rBr rBr rBr rBr rBr Y

a Y BrG

h

-

g -

Ca Y chR Y

-

pink pink

-

b

c

d

a

j

k 1

-

1

ItY Or, rBr Or,’BrBk

-

ItY Br

-

R rBr Br R P R R Ca R rY V Y B ~ R rBr brY

= = =

PER C EIT ~ O F RE- LITERATUR5 RBMARKE REAQENT SOLVENT AGENT (4) Phlorhizin dye8 silk yelDil. AcOH 1 to 5 HIOs low to blood red HzO 1 (11 ) Arbutin becomes blue FeCls (13) Precipitates ad.ditiye comCholesterol Alcohol 10 pound of digitonin Positive in 2 hour8 for Dil. K 3 Fehling’s picrotoxin colooynthin, tartrate and scillitAxin Colore in few minutes Has04 0.5 9) Colors in few minutes Hz0 92 Over HzS04 containing AoOH Trace (8) trace of FeCla /n\ Hz0 26 HNOs l oI (10, 18) Solution in AozO over 100 AcaO conod. Has04 ( 5 ) 1 hour’s standing HzO 85 HaPOi ZnCh 15 per cent H C1 3 ( 1 , 7) Immediate oolors HzSO4 0.05 Immediate colors Urotropin

{2

h

Br BrR brG

Y Y Y

green R = red orange V = violet P purple Y = yellow = dark; It = light: comma = changing to G Or

TABLE11. REAQENTS

a

k

i

CR Y

PERUUSES NEW METHODOF EXTRACTING QUININE FROM CINCHONA.Some publicity has recently been given by the Callao-Lima press t o a more economic method of extracting quinine from the bark of the cinchona plant, which is found in abundance in the jungle regions of Peru. Experiments conducted by Sefior Franciles Zamorra Silva in the laboratories of Sefior Hersino V. Sanchez, at Monzon, Peru, have resulted in a new process of obtaining quinine alkaloids and salts which may greatly affect the local production and exportation of this drug.

LITERATURE CITED Pharm., (3)19,63 (1881). .,25,193(1901);Chem. News, 73,271(1901). Dragendorff, Arch. Pharm., 234,72 (1896). Evans and Deha, J . Am. Chem. SOC.,52,3648(1930). Fltickiger, Jahresber. P h a m . , 39,129 (1911); Merck’s Ber., 51 (1911). Formanek, 2. anal. Chem., 36,409(1887). Jorisaen, Ibid., 19,268 (1871). Keller, Ibid., 36,72 (1887); 38,54 (1889). Mandelin,Ibid., 23,235 (1874). Sagel, Pharm. Zentralhalle, 55,268 (1914). Schiff, Ann., 154, 246 (1870). Venturoli-Veroi, Boll. chim. furm., 48,713 (1909). Windu, 2. physiol. Chem., 65, 110 (1910). RECEIV~PD June 16, 1934.

The production of quinine salts and alkaloids from cinchona bark produced in Peru during the past few years is not e ual t o the local demand. The public health statistics indicate t%at an average of over 2000 cases in the charity hospitals of the city of Lima alone are annually treated with quinine, and epidemics of malaria necessitating its use occur frequently throughout the provincial districts of the Republic. Any method leading to the greater economic production of this drug receives the attention of the Peruvian Government.