468
T H E JOURNAL OF I N D U S T R I A L A N D ENGINEERING CHEMISTRY
a-When working with steels high in carbon (above i t is advisable not t o use more t h a n one gram, in order t h a t filtration may be sufficiently rapid. 3-For very accurate work t h e Meyer tubes should be washed with dilute acid before beginning work each day. .After a determination is finished, t h e Meyer t u b e should be completely filled t w o or three times with t a p water, t h e n rinsed with distilled water, in order t o remove t h e carbon dioxide liberated when dissolving the carbonate from t h e previous determination. 4-The flask containing t h e carbonate should be very thoroughly agitated after adding t h e acid. since t h e carbonate sometimes dissolves rather slowly if this is not done; this is particularly t h e case if i t has packed much during filtration. j-The rubber tube connecting B (see figure) t o t h e hleyer t u b e should be washed with a little water from B , before beginning determinations each day. I a m indebted t o M r . H. L. Cleaves of this Bureau who prepared t h e drawing of t h e filtering a p p a r a t u s a n d made many determinations on steels which will appear in a later publication. 1%)
BUREAUOF STANDARDS WASHINGTON
THE DETERMINATION OF AMMONIA IN ILLUMINATING G A S By J. D . EDWARDS Received March 21, 1914
This paper is a s u m m a r y of t h e results of a brief investigation of t h e a p p a r a t u s a n d methods employed for t h e commercial determination of ammonia in illuminating gas, A fuller report will. be found in Bureau of Standards’ Technologic P a p e r No. 34, a n d t h e application of this work in t h e form of operating directions for carrying out t h e determination will be included in Bureau of Standards’ C i r c u l a r No. 48, “ S t a n d a r d Methods of Gas Testing.” T h e method generally used for t h e determination of ammonia in purified illuminating gas depends upon t h e absorption of t h e ammonia in a s t a n d a r d acid solution, t h e a m o u n t of ammonia absorbed from a measured volume of gas being determined either by titration of t h e acid remaining unneut’ralized, or less frequently b y allowing t h e gas t o pass until t h e change in t h e indicator used shows t h a t all t h e acid has been neutralized. T h e choice of t h e proper indicator t o use for this determination is of greater importance t h a n t h e choice of apparatus, since t h e use of a n unsuitable indicator may introduce large errors, amounting in extreme cases t o more t h a n one hundred per cent. Many indicators have been a n d still are commonly used which are not a t all suited t o t h e purpose, failing t o meet one or more of t h e following essential requirements: I-It should show a sharp end point in dilute solutions. 2-It should be sensitive t o ammonia a n d not be seriously affected by ammonium salts. 3-The e n d point should be affected as little a s possible by carbon dioxide. Abstract 1 Published by permission of Director, Bureau of Standards. of paper presented at the Cincinnati Meeting of the American Chemical Society, April 6-10, 1914.
Vol. 6, No. 6
T h e indicators which were found t o be most suitable for t h e determination of ammonia in gas were sodium alizarinsulfonate, cochineal a n d paranitrophenol. Sodi u m alizarinsulfonate is less sensitive t o carbon dioxide t h a n either cochineal or paranitrophenol a n d gives a color change from greenish yellow t o brown which is quite sharp even with very dilute solutions. Sodium alizarinsulfonate was t h e indicator used in t h e remaining experimental work. Methyl orange, though less sensitive t o carbon dioxide t h a n t h e above indicators, does not give sufficiently sharp color changes with weak solutions. Phenolphthalein and litmus, of course, are too sensitive t o carbon dioxide t o be of use here. The presence of glass beads which are used in some of t h e absorption apparatus may lead t o erroneous results for two reasons: ( I ) T h e beads may yield alkali on contact with t h e absorbing liquid; ( 2 ) washing of t h e beads may be incomplete. Although t h e absolute amount of alkali which might be dissolved from t h e beads is small, it may be equivalent t o a considerable percentage of t h e t o t a l a m o u n t of ammonia t o be absorbed. For this reason, i t is recommended t h a t t h e operator test t h e solubility of a n y beads he m a y use. T h e method of washing o u t t h e a p p a r a t u s should also be tested t o insure complete washing with a minimum of wash water. Five different forms of apparatus were tested: The Referees apparatus, t h e Emmerling tower, t h e Lacey apparatus, t h e common form of gas wash bottle a n d a modified form of t h e Cumming wash bottle. This latter form (Fig. I ) was designed a t t h e Bureau
H
>{
FIG. ~-MODIPIED CUMMING WASHBOTTLE(ONE-FOURTH SIZE)
of Standards fqr this work. I n this form, t h e gas passing through t h e small nozzle acts like a n injector a n d circulates t h e liquid rapidly a n d continuously, t h u s bringing fresh acid i n t o contact with t h e gas. T h e relative efficiency a n d from this t h e probable accuracy of t h e different forms of apparatus was determined by running t h e different forms in parallel, using gas from a common supply. A R / j o solution of sulfuric acid was used a s t h e absorbing agent. It was not considered desirable t o use a stronger solution t h a n this because of t h e small amount of ammonia t o be absorbed a n d t h e fact t h a t small errors in t h e measurement of stronger solutions make a large error in t h e ammonia apparently absorbed. As a result of this comparison it was found t h a t t h e Emmerling tower gave results which were somewhat higher t h a n those obtained with t h e other forms and t h a t t h e wash bottle gave results consistently lower.
.
J u n e , 1911
T H E J O l - R S . 4 L O F I S D L T S T R I dL . l S D E S G I S E E R I N G C H E X I S T R Y
I n a series of I O tests, in each of which four different a p p a r a t u s were r u n in parallel. t h e maximum difference between t h e high a n d low results of each test ,expressed as a percentage of t h e average) was 8.3 ?er cent a n d t h e average difference 4.j per cent. The ammonia content of t h e gas was varied from I t o 2 0 grains per I O O cubic feet. ( F o r full experiS oY. 34, above mental details. see Techtiologic P C I ~ C referred to.) d series of tests in n-hich t h e gas after passing through t h e first absorption a p p a r a t u s passed through a n Emmerling tower. showed, in general. t h a t t h e amounts of ammonia escaping t h e first a p p a r a t u s b u t absorbed in t h e Emmerling tower were not detectable within t h e limits of error of t h e titration. With careful operation. a n y one of t h e fil-e forms of a p p a r a t u s tested would ordinarlly gix-e results t h a t are well within t h e limits of accuracy required for this determination. either for commercial control work or for t h e purpose of gas inspection. T h e wash bottle appears t o be slightly less efficient as a n absorber t h a n t h e other forms, b u t still i t gives satisfactory results. I t is difficult t o make a n y comprehensive s t a t e m e n t defining satisfactory results. I n general, results on gas containing up t o a b o u t j grains of ammonia per I O O cubic feet should be within I O per cent of t h e ammonia content of t h e gas. although t h e percentage error m a y be greater when t h e ammonia is I grain or lower. With gas containing more t h a n j grains ammonia, t h e percentage error should decrease somewhat. B E R E A UO F
STANDARDS,
W4SHISCTON
F R . I C T I O S . A L DISTILLATIOS-300 C C . O f t h e crude petroleum were introduced into a side t u b e distilling flask, of about j o o cc. capacity, a n d distilled, t h e heat being so regulated t h a t about 2 . j cc. of distillate passed over per minute. The average results of duplicate distillations are t h e following: Fractions OC
BY
TETSV.KATAYAZl.4
Received April 1. 1911
Favorable indications of petroleum deposits have been found in Formosa Island in many districts along t h e western slopes of t h e middle mountain range. Of these oil deposits t h a t a t Shukkokosio. about seven miles south of Bioritsu station on t h e main railway line in t h e island. is t h e most important. a n d is now worked b y t h e Howden Petroleum Company. I t is reported t h a t about 3 > 0 0 0 gallons of crude petroleum are obtained daily from a single well there. Several years ago t h e author studied t h e physical properties of this crude petroleum a n d found t h a t t h e kerosene oil obtained from t h e crude petroleum b y t h e ordinary method can not be used for l a m p oil, t h e flame being very smoky. F u r t h e r s t u d y h a d t o be postponed. b u t in M a y , 1913, i t was again resumed. By means of acetic anhydride. t h e smoky constituent was isolated a n d its n a t u r e studied. a n d i t xyas a t last found t h a t t h e kerosene oil m a y be refined b y changing t h e temperature a n d duration of t h e reaction on ordinarv sulfuric acid t r e a t m e n t . The results t h u s obtained are s u b m i t t e d bel o IT. PKoPERTIES
OF
THE CRL-DE P E T R o L E U J 1
T h e crude petroleum is a clear. mobile, brownish oil of specific gravity 0.831 a t 1 5 ' c.; i t s smell is rather agreeable; i t solidifies a t o o C.
Per cent b y volume
S p gr a t 1.5'
1.5
......
l5,8
0.iii0
21.8 12 2
8.8 7.8 i.6 7.5
4.3 13.2
C
0.7980 0.81.55 0.8205 0,8360 0.8585 0.8790 SoiidiAes a t ordinary temperature
I t is remarkable t h a t t h e specific gravity of each fraction of this crude petroleum was very high-much higher t h a n t h a t of t h e corresponding fraction of other crude petroleums. BLRxIsG TEST-The kerosene fraction. distilling between I jo" C . a n d 2 7 j o C . . was refined with concent r a t e d sulfuric acid b y t h e ordinary method, washed with water sex-era1 times. t h e n with a dilute alkali solution. a n d again with water until t h e oil became free from acid a n d alkali. T h e kerosene oil t h u s refined was burned in a l a m p of ordinary construction. b u t t h e flame was very smoky. T E S T F O R S I T R O G E S A S D svLFuR---The crude petr0leum was heated t o boiling for a long time with some small pieces of metallic sodium, in a flask equipped with a reflux condenser. After cooling, t h e sodium was tested for cyanocompounds a n d sodium sulfide, b u t no test for either of these compounds was obtained. 11-SOLUBILITY
THE STUDY OF THE CRUDE PETROLEUM FROM BIORITSU, FORMOSA
469
O F THE CONSTITUENTS O F
THE C R C D E
P E T R O L E U hl
A i t first a n a t t e m p t was made t o isolate t h e smoky constituent in t h e petroleum by distillation. b u t it was impossible. Every fraction separated b y cautious fractional distillation g a r e a smoky flame. T h e n a n a t t e m p t w a s made t o separate t h e smoky constituent by a solvent. Edeleanu suggested t h a t aromatic compounds a n d other hydrocarbons. rich in carbon atoms, m a y be dissoll-ed away from t h e oil b y liquefied sulfur dioxide. a n d Prof. Engler recommended this method as effective.' I t was considered desirahle t o t r y this method. b u t t h e temperature of t h e laboratory a t t h a t time, always above 30' C., did not permit of this procedure. Therefore another solvent. which would e s tract t h e smoky constituent from t h e petroleum a t ordinary temperature, was sought, a n d a t last i t was f o u n d t h a t acetic anhydride was most suitable for this purpose. EXPERIXEST 1-2 j o cc. of t h e fraction distilling between I jo' C. a n d z j j o C. were introduced into a separating funnel a n d acetic anhydride was added, little b y little, shaking well between each addition. .it t h e beginning t h e added acid dissolved in t h e petro'leum, b u t when 6 0 cc. of acid h a d been added t h e fluid separated into two layers, t h e lower layer being 9 cc. After t h e lamer layer mras drawn off, 1 0 cc. more of t h e acid !\rere added t o t h e upper layer, when 2 7 cc. separated as a lower layer. T h e lower layer was drawn 1
Zfschr. a n g c u ' . Chem., 1913, p. l i i .
