July 15, 1931
INDUSTRIAL AND ENGINEERIN% CHEMISTRY
value SO obtained was 40.4 per cent, an increase of 0.6 per cent over the value obtained when the analytical procedure given was strictly followed.3
273
(4) Green and Perkin, J . Chem. Soc., 89,811 (1906). Weltzien*and Messmer#Ann.*4359 e4 (1924). , (6) Knoevenagel, Chem.-Zlg, 39, 248-9 (1922) (7) Knoevenagel and Konig, Cellulosechemie, 3, 113-21 (1922), (8) Kruger. Farben-Zlg , 36,2032 (1930). Literature Cited (9) Mork, J . A m . Chem. Soc., 31, 1069 (1909). (10) Ost, 2. angew. Chem , 19,993 (1906). (1) Cross and Bevan, Worden Tech. Cellulose Esters VIII, 2 (11) Ost. Chem.-Ztg, 32, 815 (1908). (2) Eberstadt, Dissertation, Heidelberg, “uber Acetylcellulo Schultze and Hew, Ann , 490, 65 (1925) (3) Freudenberg, Ann., 433,230 (1923). - (12) (13) Torii,’J. C h x . I n d . (Japan),25, 118-31 (1921). ’ a Subsequent to the carrying out of this work, a procedure using pyri(14) Weltzien and Singer, Ann., 443, 71 (1925). dine was published by Battegay and Penche, Bull. SOC. chim., 46, 132 (J929). (15) Woodbridge, J . Ana Chena. Soc ,31, 1068 (1909). Hessp
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Determination of Phenols in Water Solution Adaptation of Bromine Method to Include Range of 1 to 75 p. p. m.‘ J. A. Shaw2 MELLON INSTITUTE
OF
INDUSTRIALRESEARCH, UNIVERSITY OF PITTSBURGH, PITTSBURGH, PA.
Perhaps the most frequently used method for deRAPID m e t h o d for stand 2 or 3 minutes. Sepatermining phenols in coke-plant effluents and similar rate the two layers. Wash the determination of process liquors is the bromine method. This method phenols in solutions the aqueous layer twice more was not readily applicable to samples containing much with 75-ml. portions of ether such as gas liquor was publess than 75 p. p. m. phenol. The present article delished by the writer in 1929 a n d combine t h e e t h e r scribes a simple procedure making it appliczable to washes. Now discard the (1) and, from the testimony the analysis of samples having a concentration of 1 a q u e o u s l a y e r a n d place of many c h e m i s t s usingit, p. p. m . phenols or even less. Lower concentrations the ether in the separatory it a p p e a r s to h a v e given than this in plant liquors are usually of little imfunnel. e n t i r e s a t i s f a c t ion when Wash the ether three times applied within t h e l i m i t s portance. with 8-ml. p o r t i o n s of 10 specified. However, the method without modification was not applicable to a sample per cent sodium hydroxide solution and finally with one containing less than 75 p. p. m. phenols. It is therefore 10-ml. portion of distilled water, combining these aqueous evident that it is applicable to the most important of the alkaline washes. Boil gently to remove most of the ether, phenol-bearing plant effluents, but that it is not satisfactory cool, and dilute to a volume of 50 ml. in a small graduated for the analysis of a large number of plant effluents con- cylinder. I n removing the ether from the caustic by boiling, taining perhaps only a few parts per million of phenols. the solution becomes first turbid and then clear, indicating At the present time the methods employed in analyzing these the disappearance of most of the ether. All of the phenol in the sample has now been concentrated effluents for phenols are time-consuming and in some cases actually grossly inaccurate. For this reason it is believed into the 50 ml. of caustic solution. This may now be analyzed that a real need exists for a rapid and reasonably accurate according to the previously published method if the concenmethod for determining phenols in liquors having a tar tration of phenol in the original sample was not less than acid concentration between 1 and 75 p. p. m. I n the course 5 p, p. m. To save time it is well to take a few milliliters of some work done in The Koppers Research Corporation of the caustic solution, make just acid to methyl orange Laboratories, this need became acute and a variation of the with sulfuric acid, and add two volumes of distilled water previously published method was developed to meet this and a slight excess of bromine water in a small test tube. If a distinct turbidity is not produced, the phenol must be situation. The variation in procedure consists simply in concentrating further concentrated. To do this, note the volume of the the phenols into caustic soda solution by means of ether3 caustic solution, acidify with sulfuric acid, and repeat the [ (C2H&O ] washes, heating the sodium hydroxide solution previous procedure for concentrating with ether. In this to drive off the ether (and certain other impurities) and then case the small separatory funnel should be employed. Use applying the previously published method of Shaw (1) three 10-ml. portions of ether and three 3-ml. portions of to the acidified caustic solution. caustic, supplementing the caustic washes with one water wash of 3 ml. volume. The aqueous alkaline washes should Apparatus and Reagents . be dropped directly into the 8 X 1 inch (20.3 X 2.5 cm.) In addition t o the apparatus and reagents originally test tube in which the final phenol distillation is to be made. specified, a separatory funnel for 1000 ml., and one for 100 Calculations ml., and U. S. P. ethyl ether (C2H&0 are required. Assume only one series of ether washes to have been made. Procedure Then By means of a graduated cylinder, measure 800 ml. of p. P . m. phenol in standard matched X dilution factor sample into the large separatory funnel. Acidify with sulconcentration factor furic acid. Add 125 ml. of ether, shake well, and allow to = p. p. m. phenol in sample 1 Received March 10,1931. For example, a 750-ml. sample was washed with ether and 2 Industrial fellow, Multiple Fellowship of The Koppers Research caustic solution as above described and the caustic diluted Cocp., Mellon Institute, Pittsburgh, Pa. * The chemists of the U. S Steel Corp. use ether for this purpose in a to exactly 50 ml. Ten milliliters were acidified and distilled, and 25 ml. of distillate were caught. When 10 ml. of dissomewhat different connection.
A
AN A L Y TICAL EDI TI 012'
274
tillate were diluted to 15 ml., they matched 30 p. p. m. standard upon bromination. Then
:$
The ether, after having been thoroughly washed with both dilute caustic and acid, may be saved if desired and used for subsequent work. I n addition to making possible the rapid analysis of waters containing relatively low concentrations of phenols, this preliminary treatment renders the previously published method satisfactory for determining phenols in ammonia liquors dephenolized by immiscible solvents. For some reason not well understood by the writer, the bromine method as previously published failed to give good results on liquors dephenolized in this manner. It is the writer's opinion that this difficulty arose from the relatively large amount of thiosulfate which is usually formed when handling sulfide-bearing liquors in contact with air.
= 7 . 5 ~p.. m. phenol
Discussion
By the procedure as outlined, solutions containing 1 p. p. m. of phenols or even less can be analyzed in 1 hour, and the error shDuld be distinctly less than 10 per cent. The following results are some that were obtained on synthetic solutions : In sample P. P. m. 25 0 5 0 1 0
PHENOL
VOl. 3, No. 3
Found P. p . m. 25.1
Literature Cited
4.80
(I) Shaw, J A,, IND END.C H B M .Anal. , Ed., 1, 118 (1929).
1.00
Determination of Organic Halogen b y Liquid Ammonia-Sodium Process* Thomas H. Vaughn and J. A. Nieuwland DEPARTMENT OF CHEMISTRY,
UNIVERSITY OR
NOTRED A M E 8 NOTREDAXE, IND.
The liquid ammonia process for the determination tions, using tetrachloroethylof organic halogen has been modified SO as to dispense the action of soluene as an example: with all special apparatus, to increase the accuracy, tions of sodium in c1 and to reduce the time required for a complete deliquid ammonia on organic \ termination. By the modified method determinations haloids, it occurred to the c=c +4NaNHz+ are extremely BimpIe, very accurate, and require in authors that since halogens \Cl c1/ most cases only 20 to 40 minutes for completion. were apparently q u a n t i t a The modified method has been applied to the de2 " tively removed from all types termination of organic fluorine and gives excellent of organic compounds, this \ /", 4NaCI results. * /c=c\ method of treatment might be used as a basis for halogen 2" 2" determination. Such proved to be the case. NHz \ I", On looking up the literature, it was found that Chablay + HN=C=C=NH 2NHa (1) had employed this reaction for the determination of organic /c=c\ chlorine, bromine, and iodine; and that Dains and co-workers 2" NHz (2, 8) had used the method and investigated the possibility HN=C=C=NH 2NaNHz + 2NaCN 2NHs of error caused by cyanides produced during the decomposiSimilar equations can be written for all observed cases of tion. According to the method described by Chablay, the sub- cyanide formation. stance is placed in a special reaction tube which is cooled I n the procedure to be described, the original Chablay in a bath of solid carbon dioxide and acetone. Ammonia method has been modified in such a manner as to increase is condensed in the tube and metallic sodium added. After the rapidity and accuracy of analysis of insoluble materials completion of the reaction, the ammonia is distilled off and and to do away with all special apparatus. the halogen precipitated as silver halide. This method, while Modified Procedure very rapid for compounds soluble in liquid ammonia, requires an hour or more for the decomposition of insoluble substances. Fifty milliliters of liquid ammoniaare run into a 400-~1. With insoluble compounds, moreover, low results are usually beaker and 0:1to 0.4 gram of the halogeno-organic iaterial obtained added. If solution does not take place upon stirring, ether, D a h s and Brewster (9) investigated the action of sodium monobutylamine, dimethyl acetal, or other organic solvent in liquid ammonia on organic compounds and examined the inert towards sodium in liquid ammonia is slowly added until products of reaction for cyanide. They found that cyanides the material is dissolved. One gram of freshly cut metallic were Produced from haloen compounds in Only a few cases* sodium is then added in small pieces and the covered beaker It is interesting to note that in all of these cases two or more allowed to stand until the reactionis complete(usually 30 halogens were attached to a single carbon atom. I n view of seconds to 2 minutes). At this point the solution should this fact, and since it is known that one of the principal prod- have a persistent blue colorof uniform depth. ~i~~grams of ucts of the reaction of sodium in liquid ammonia on organic ammoniumnitrate dissolved in few of liquid haloids is an amine, the production of cyanide in these special ammoniaare now added to the excess sodium. The cases can probably be by the following set Of reac- covered beaker is placed in a water bath at room temperature, and the solution allowed to evaporate to dryness (hood). The 1 Received March 13, 1931.
HILE investigating
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