Industrial and Engineering Chemistry : analytical edition, Vol. 11, No. 10

IN D U ST R IA L

aíENGINEERIN«

C H E M IS T R Y

Vol. 31, C o n secu tiv e N o. 39

ANALYTICAL EDITION

21,300 Copies of This Issue Printed

Issu ed O ctober 20, 1939

H arrison E. H o w e, E ditor

Vol. 11, N o. 10

De t e r m i n a t i o n o k Hi g h Vi s c o s i t i e s b y Me a n s o f Ga r d n e r Mo b i l o m e t e r...

...E. L. Baldesehwieler and L. Z. Wilcox

Ph e n o l s i n Lo w- Te m p e r a t u r e Ta r...

...Thomas B. Smith and Leo Kasehagen

Ba r o m e t r i c Co r r e c t i o n No m o g r a p h f o r Hy d r o g e n El e c t r o d e...G. F. Ki n n e y

De t e r m i n a t i o n o f Bi s m u t h b y Qu i n a l d i n e Sa l t o f Io d o b i s m u t h o u s Ac i d ...

... J. R. Ilayes and G. C. Chandlee

Di r e c t De t e r m i n a t i o n o f Al u m i n a i n Ce r t a i n Si l i­ c a t e s ...E. W. Koenig

De t e r m i n i n g Ri b o f l a v i n i n Dr i e d Mi l k Pr o d u c t s

...Royal A. Sullivan and L . C. Norris

Bo r o n De t e r m i n a t i o n i n So i l s a n d Pl a n t s Us i n g Qu i n a l i z a r i n Re a c t i o n . K. C. Berger and E. Truog

Vo l u m e- Sh a p e Fa c t o r o f Pa r t i c u l a t e Ma t t e r . . .

...J. M . Dalla Valle and F . H . Goldman

Ju d g i n g Ad h e s i v e n e s s o f Bi t u m e nt o Si l i c a Sa n d . .

...Hans F. W interkorn and Geo. W. Eckert

Ta b l e f o r Eb u l l i o m e t e r s...R. F. Love

Mo d i f i e d Jo n e s Re d u c t o r...W . A . Taebel

De v i c e f o r Su b l i m i n g Io d i n e...

...Jacob Cornog and Leonard Olson

Ra p i d Op e r a t i n g De v i c e f o r Or s a t 'Ap p a r a t u s . . .

525

527

530

531

532

535

540

545

546 548 550

551

Fred Cook 551

fo r th e T h e A m e ric a n C hem ical S o ciety assum es no re s p o n sib ility

M b

La b o r a t o r y Li f t i n g De v i c e . . . . George Calingaert 552

Mi c r o c h e m i s t r y :

De t e r m i n a t i o n o f Wa t e r i n Pa p e r- In s u l a t e d Ca b l e s a n d In s u l a t i n g Oi l ...

. R. N. Evans, J. E. Davenport, and A. J. Revukas 553

Mi c r o s c o p i c Id e n t i f i c a t i o n o f Su g a r s...

... John A. Quense and William M. D ehn 555

Di s t i l l a t i o n Ca p i l l a r y . . . Alexander O . G ettler 559

P r e p a r a t i o n o f I m m e r s i o n L i q u i d s f o r R a n g e n o =

1.411 t o 1.785 . . E. P. Kaiser and William Parrish 560

La b o r a t o r y Eq u i p m e n t:

Mo n o c h r o m a t o r sa n d Au x i l i a r y Ap p a r a t u s . . .

... John Strong 563

Co o r d i n a t i o n b e t w e e n In s t r u m e n t Ma k e r a n d Re s e a r c h...William H . Reynolds 567

Sp e c t r o g r a p h De s i g n a n d It s Pr o b l e m s...

... J. W. Forrest 568

La b o r a t o r y Su p p l y Ho u s e... D . A . K orm an 571

An a l y t i c a l a n d Mi c r o b a l a n c e s . A . W. Ainsworth 572

La b o r a t o r y Ap p a r a t u s, It s Ev o l u t i o n a n d De­ v e l o p m e n t ... Wm. B . W arren 574

Re s e a r c hi n In s t r u m e n t a t i o n...

... Paul Sherrick and Lynn D . Wilson 576

Re s e a r c h o n Op t i c a l In s t r u m e n t s . C . W. Barton 579

Te s t i n g o f Ch e m i c a l Ba l a n c e s . . Archibald Craig 581

s ta te m e n ts a n d op in io n s a d v a n c e d b y c o n trib u to rs to it s p u b lic a tio n s.

P u b l i c a t i o n O ffice* E a s t o n , P e n n a .

E d i t o r i a l O flic c : R o o m 706, M ills B u ild in g , W a s h i n g t o n , D . C . A d v e r tis in g D e p a r t m e n t : 332 W e s t 4 2 n d S t r e e t , N ew Y o r k , N . Y . T e l e p h o n e : N a i i o n a l 0848. C a b l e : J i e c h c m ( W a s h in g t o n ) T e le p h o n e : B r y a n t 9-4430

P u b lish e d b y th e A m erican C h em ical Society, P u b lic a tio n Office, 2 0 th &

N o rth a m p to n S ts., E a s to n , P e n n a . E n te re d as second-class m a tte r a t th e P o s t Office a t E a s to n , P e n n a ., u n d e r th e A c t of M arch 3, 1879, as 48 tim es a y ear. In d u s tria l E d itio n m o n th ly on th e 1st; A n a ly tic al E d itio n m o n th ly on th e 1 5 th ; N ew s E d itio n on th e 1 0 th a n d 2 0 th . A ccep tan ce fo r m ailing a t special ra te of p o stag e p ro v id e d fo r in S ectio n 1103, A c t of O c to b er 3, 1917, a u th o riz e d J u ly 13, 1918.

Ra t e sf o r Cu r r e n t Nu m b e r s: A n n u al s u b sc rip tio n r a te s: In d u s t r i a l a n d En g i n e e r i n g Ch e m i s t r y co m p lete $ 6 . 0 0 ; ( a ) In d u s tria l E d itio n $ 3 . 0 0 ;

(6) A n a ly tic a l E d itio n $2.50; (c) N ew s E d itio n $1.50; (a) a n d (6) to g e th e r

$5.00. F o reig n p o stag e to c o u n trie s n o t in th e P a n A m erican U n io n , $2.40;

(a) $1.20;^ (6) $0.60; (c) $0.60. C a n a d ia n p o stag e one th ir d th e se ra te s.

Single copies: (a) $0.75; (6) $0.50; (c) $0.10. Special ra te s t o m em bers.

N o claim s c an b e allow ed fo r copies of jo u rn a ls lo st in th e m ails unless such claim s a re received w ith in s ix ty d a y s of th e d a te of issue, a n d no claim s will be allo w ed fo r issues lost as a re su lt of insufficient n o tice of ch an g e of address. (T en d a y s ’ a d v an c e n o tice re q u ire d .) “ M issing fro m files’*

c a n n o t b e accep ted as th e reason fo r h o n o rin g a claim . C h arles L . P a rso n s.

Business M an a g e r, M ills B uilding, W a sh in g to n , D . C ., U . S. A .

4 INDUSTRIAL AND ENGINEERING CHEMISTRY VOL. II, NO. 10

Send for the new catalog of M allinckrodt Analytical Reagents and Laboratory Chemicals showing maximum limits of impurities of nearly 500 chemicals for research and control labo­

ratories.

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ST. LOUIS, M O . PHILADELPHIA TO RO NTO NEW YORK, N.

y.

CEMENT ANALYSIS ^requires

ACCURATE ALKALI DETERMINATIONS

For vital analytical accuracy many cement chemists prefer the J. Lawrence Smith method for detecting minute quantities of alkali. This procedure requires a calcium carbonate reagent with particularly low alkali content, such as—

C A L C IU M C A R B O N A TE A .R . L O W A L K A L I (Mallinckrodt)

Refined to predeterm ined standards, this reagent has been especially developed for use in the J. Lawrence Smith method of alkali determinations. I t is always uniform in composition and reaction.

O th e r Reagents for the Cement Chemist

AMMONIUM OXALATE SODIUM AMMONIUM PHOSPHATE

POTASSIUM CARBONATE SODIUM ACID PHOSPHATE

POTASSIUM HYDROXIDE SODIUM CARBONATE

POTASSIUM PERMANGANATE SODIUM HYDROXIDE

Sen d for free technical bulletins on these two essential instruments.

Coleman Electric Co., Inc.

310 Madison St. Maywood, III.

5 0 0 6 0 0 7 0 0 8 0 0 9 0 0 I000

WAVE LENGTH— MILLIMICRONS

*C u rve s fo r C o b a lt S u lfa te S olution 1. I gram C o b a lt S u lfa te p e r lite r.

2. 10 gram s C o b a lt S ulfate p e r lite r.

3. 0 .0 I g ra m C o b a lt S u lfa te p e r lite r.

* U sing nitroso-R -salt fo r d e te c tio n .

are the keys to accurate

control of com plex liquids in chemistry!

All liquids are coloredl The C olem an M o d e l 10 R egional S p e ctro ­ p h o to m e te r allows a continuous selection o f m o n o ch rom a tic lig h t values, th ro u g h and fa r beyond b o th ends o f th e visible spectrum . Curves can thus be established fo r even so-called colorless liq u id s; curves which show co lo r a b so rp tio n characteristics and th e re la tive concen­

tra tio n o f colored in g re d ie n ts in these solutions. These curves are o f inestim able com m ercial value because th e y p e rm it accurate d u p lica tio n o f co lo re d liquids and re a d ily disclose th e presence o f fo re ig n color ingredients, o fte n invisible to th e human eye. The C olem an M o d e l 3 p H E lectrom eter, undisputed le a d e r in th e fie ld o f p H measurements, is used on the o u tp u t o f th e M o d e l 10 R-S-Photom eter to in d ic a te the ra tio o f lig h t in te n sity th ro u g h a te s t solution to th a t th ro u g h a standard solution d ire c tly as p e rce n t tra n sm itta n ce w ith o u t co m p u ta tio n s. Submit two one-ounce samples of any liquids from your regular production for free color analysis and p H determ ination. Instructions fo r handling must accompany toxic, volatile, explosive, or bacteria laden solutions.

M odel I0 R-S-Photometer

LUz

o

WAVE LENGTH— MILLIMICRONS

C urves fo r Linseed O il 1. S pecial re fin e d linseed o il.

2. B oiled linseed o il.

M odel 3 pH Electrom­

eter

z

u

4 0

6 INDUSTRIAL AND ENGINEERING CHEMISTRY VOL. 11, NO. 10

D E TE R MI NA T IO NS

jg/ j t a 'F ' A r e y o u c o n c e r n e d

1 ] J l . ^ w i t li a m m o n i u m

j& T 1 c o m p o u n d s , n itra te s

1 m o r n i t r o g e n o u s

org an ic co m p ou n d s?

D o you w ish to know total N itrogen con tent?

W hichever y ou are d eterm in in g, you w ill want to u se R eagen ts w hose u n ifo rm ity assists in as­

su rin g con sisten t resu lts . . . and, in th e case o f K jeld ah l d eterm in atio n s, w hose low N itrogen con ­ tent en ab les you to obtain the u n ifo r m ly sm all blanks w hich lead to h igh er accuracy.

T o fill this n eed , s ta n d a rd ize o n B & A R ea g en ts!

A fe w o f th e B & A R e a g e n ts m o st o f t e n u s e d fo r N itr o g e n d e te r m in a tio n s a re:

CODE NO.

1050 A cid B o r ic , P o tc d e r , R e a g e n t, A .C .S .

1180 A cid S u lfu r ic , C .P ., S p e c . G r. 1 .8 4 , A .C .S ., L o iv in I \ 1217 A lu m in u m M eta l, G r a n . 2 0 M e s h , R e a g e n t 1651 C u p ric S u lfa t e , F in e C r y s t., R e a g e n t, A .C .S . 1681 D e v a rd a ’s A llo y , 2 0 M e s h , P o w d e r , R e a g e n t 1964 M ercu ric C h lo r id e , C r y s t., R e a g e n t, A .C .S . 1969 M ercu ric O x id e , R e d P o w d e r , R e a g e n t 2118 P o ta s s iu m H y d r o x id e , P e lle ts , R e a g e n t, A .C .S . 2120 P o ta s s iu m I o d id e , C r y s t., R e a g e n t, A .C .S . 2129 P o ta ssiu m P e r s u lfa te , R e a g e n t

2138 P o ta s s iu m S u lfa t e , P o w d e r , R e a g e n t, A .C .S . 2255 S o d iu m H y d r o x id e , P e lle ts , R e a g e n t, A .C .S . 2256 S o d iu m H y d r o x id e , F la k e , 7 6 % , f o r N itr o g e n

D e te r m in a tio n

2296 S o d iu m S u lfa t e , A n h y d r o u s , P o w d e r , R e a g e n t 2422 Z in c M eta l, G r a n ., 3 0 M e s h , R e a g e n t, A .C .S .,

L o w A s, P b a n d F e

B ^{a k e r} ^ A d a m s o n

FINE C H EM ICALS L A B O R A T O R Y . REAGENTS y

ANALYTICAL EDITION 7

THE S T A N D A R D

IN MOST LABORATORIES

MULTIPLE UNIT

ELECTRIC FURNACES

O R G A N IC C O M B U S TIO N FURNACE 3 STANDARD SIZES

A B O V E -

C R U C IB L E FURNACE 5 S TA N D A R D SIZES M U F F L E FURNACE

4 S TA N D A R D TYPES

A T L E F T -

S O LID C O M B U S TIO N T U B E FURNACE

10 STA N DA RD SIZES

H IN G E D C O M B USTIO N TU B E FURNACE

10 STA N DA RD SIZES

H O T PLATE— 6 S TA N DA RD SIZES

W R ITE F O R DESCRIPTIVE BU LLETIN S

H E V I D U T Y E L E C T R I C C O M P A N Y

T R A D E M A R K

LAB O R ATO RY FURNACES

MULTIPLE UNIT

R E G . U . S . P A T . O F F .

M I L W A U K E E , W I S C O N S I N

8 INDUSTRIAL AND ENGINEERING CHEMISTRY VOL. 11, NO, 10

C E N C O P R E S S O V A C 4 P U M P

Large free air displacement . . . 34 liters per m inute • Tested to a ttain a vacuum of 0.1 mm or less. . . test d ata show all pumps produced so far attain much lower pressures • W hen compressed air is required . . . this pum p will satisfy the need . . . 10 lbs per square inch. M ay be used to circulate or col­

lect gases . . . fumes from distillations m ay be conducted to vents • These features are of value to the ch em ist. . . and a t a price lower th an ever before • Specify No. 90510A for 115 volts 60 cycle current.

S C I E N T I F I C F f f l f f j L A B O R A T O R Y I NSTRUMENTS U IlU J A P P A R A T U S

KEau&pAT.^ri.

New York • Boston • C H I C A G O • Toronto • Los Angeles

1700 IR V IN G PARK BOULEVARD, CH IC A G O , ILL.

C H R O M E L - A L U M E L

L E A D S A N D C O U P L E S

t h a t h e a d - l i n e s a y s w h a t y o u k n o w to b e tr u e , w e s u g g e s t t h a t y o u i n v e s t ig a t e t h e le a d w ir e y o u a re u s in g w i t h y o u r C h r o m e l- A lu m e l c o u p le s . I f t h e le a d s C h r o m e l- A lu m e l, t o o , t h e n y o u ’re a ll r ig h t . . . .B u t i f y o u a re u s in g s o - c a lle d “ c o m p e n s a t i n g ” le a d s , y o u o u g h t t o k n o w t h a t t h e y c o m p e n s a t e o n ly a t p r e t t y lo w t e m p e r a t u r e s . B u t o f t e n t h e i r j u n c t i o n w it h t h e c o u p le g e t s v er y h o t , a n d s o m e t i m e s o n e s id e is h o t t e r t h a n t h e U n d e r t h e s e c i r c u m s t a n c e s y o u g e t a n error t h a t ’s s ig n if ic a n t . S o , s e n d fo r F o ld e r -G Y , a n d le a r n w h y y o u s h o u ld u s e C h r o m e l-A lu r r ie l le a d s w it h C h r o m e l-A lu m e l c o u p le s . . . . H o s k in s M a n u f a c t u r in g

, D e tr o it, M ic h ig a n .

ALWAYS WHAT

' w i ' a r *

10 INDUSTRIAL AND EN G IN EERIN G CHEMISTRY VOL. 11, NO. 10

7890. L arge M odel, D ouble D e p th 7886. S m a ll M odel

Show ing d o o r closed a n d c la m p in p o sitio n S h o w in g d o o r a n d c la m p rem o v ed

WEBER ELECTRIC VACUUM OVENS. W ith au to m a tic control an d p o in te r scale for ap p ro x im a te settin g directly a t an y desired te m p e ra tu re up to 150°C, an d w ith a cylindrical v ac u u m cham ber w ith th ree rem ovable shelves as show n above. T h e exterior is m ade of Stainless steel th ro u g h o u t; th e v acuum ch am ber is of pressed steel, b o th copper an d nickel p lated . T h is co n stru c tio n reduces th e possibility of leakage som etim es enco u n tered w ith cast cham bers.

A new type door clamp, suggested by D r. Samuel E. Pond, of th e M arine Biological Laboratory, Woods Hole, Mass., makes it possible to use the Vacuum Oven as a low pressure oven, i.e., for internal pressures not exceeding 5 lbs. per square inch, which facilitates rapid and complete interchange of gases. The door clamp, w ith hand screw for tightening, bears centrally on the door and a t four points on its frame.

T he unique feature of the vacuum chamber is the tight fit secured by means of a lead gasket on the door. Seating is simply and quickly accomplished by slight rotation of the door into position, and final adjustm ent by tightening the screw clamp. Since the seal is not dependent upon machined surfaces, there is no possibility of nicks with the consequent delay and inconvenience involved in their repair. After continued use, the gasket can be quickly replaced from the spare set furnished w ith the oven. The lead gasket forms such an excellent seal that a vacuum can be held almost indefinitely. For ex­

ample, on an Oven evacuated to 29l/ i inches of mercury, there was no change in the gauge reading four months after evacuation ceased.

A snap switch on th e front of the tem perature regulator com partm ent provides for convenient turning on and off of the current. A combined vacuum and pressure gauge, w ith red sector above safe working pressure, is mounted on th e top of the Oven, together with two hand valves. The upper valve adm its air or any desired gas to the vacuum chamber through a tube

“A” which runs down the back and to the bottom of the vacuum chamber, where it term inates near the front; the lower valve connects to a larger concentric tube “ B ” w ith opening in the back of th e vacuum chamber below the bottom shelf. This valve is connected to the vacuum line through its intake coupling.

7886. W eber Electric Vacuum Oven, Small Model, as above described, outside dimensions 1372 X 1 2 y 2 X IOV2 Code inches, with vacuum chamber 8 inches deep X 73A inches diameter, w ith three shelves. Maximum cur- W ord ren t consumption 500 watts. W ith therm ometer. F or 110 volts a.c... 200.00 Lydha 7888. Ditto, Large Model, outside dimensions I6V2 X 153/s X 121/ , inches, w ith vacuum chamber 9V2 inches deep X

9 7 2 inches diameter. Maximum current consumption 800 w atts. F or 110 volts a.c... 275.00 Lyean 7890. Ditto, Large Model, Double Depth, identical with 7888 b u t w ith vacuum chamber 19 inches deep X 972

inches diameter. Maximum current consumption 1800 watts. F or 110 volts a.c...350.00 Lyepi Copy o f pam phlet EE-106 giving detailed description o f above Vacuum Ovens, together w ith

Weber Drying Ovens o f various sizes, sent upon request.

A R TH U R H. T H O M A S C O M P A N Y

R E T A IL —W H O L E SA L E — E X P O R T

LABORATORY APPARATUS AND REAGENTS

W EST W A S H IN G T O N SQUARE P H IL A D E L P H IA , U. S. A.

C able Address, “B alance,” Philadelphia

W EBER E L E C T R IC VACUUM OVENS

O F S T A IN L E S S S T E E L , W IT H V A C U U M C H A M B E R O F PRESSED S T E E L

A1H0RGAS

IN D U STR IA L «„a ENGINEERING CHEM ISTRY

ANALYTICAL EDITION H a r riso n E. H o w e , E d ito r

D eterm ination o f H igh Viscosities

B y M eans o f the G ardner M obilom eter

E . L . B A L D E S C H W I E L E R A N D L . Z . W IL C O X , S t a n d a r d O il D e v e l o p m e n t C o ., L in d e n , N . J .

A s e tu p for G ardner m o b ilo m e te r s is d e ­ scr ib ed , w h ereb y a cc u r a te te m p e r a tu r e c o n ­ trol a n d ea sy o p era tio n are o b ta in e d . T h e co n c lu s io n s o f C o r n th w a ite a n d S cofield th a t th e co r rela tio n b e tw e e n a b s o lu te v isco sity a n d m o b ility is a s tr a ig h t lin e h av e b e e n ch eck ed b y t h e a u th o r s for m u c h h ig h e r v is­

c o s itie s , a t variou s te m p e r a tu r e s, a n d for d ifferen t d isk s. P rovid ed rigid c o n tr o l o f tim e a n d te m p e r a tu r e is o b ta in e d a n d i m ­ p ro v em en ts in m e c h a n ic a l c o n s tr u c tio n are m a d e , t h e m o b ilo m e te r ca n b e u se d as a p r e c isio n in s t r u m e n t for th e d e te r m in a tio n o f a b so lu te v isco sity .

T

trol instrument to secure uniformity in consistency between different batches of a given product. The instrument was first recommended for control in paint and lacquer manu­

facturing. Later, Gardner and Van Hueckeroth (4) extended its use to the testing of food products, mineral oils, vaseline, and coal tar. The instrument has also been described at length by Sward and Stewart (6). While no claim for high accuracy of results obtained with the instrument was made by Gardner and Parks (S), Cornthwaite and Scofield (2) showed that under rigid control of temperature and time the apparatus gave a remarkably close correlation with the absolute vis­

cosity of a number of samples possessing true fluid flow. This correlation resulted in a straight line passing through the origin whsn plotted on rectangular coordinates.

The work of Cornthwaite and Scofield (2) was, however, limited to oils of relatively low viscosities (about 8 poises).

I t was necessary for this laboratory to determine a number of mobilities and viscosities of much higher values with a fair degree of accuracy. For this purpose the relationship be­

tween viscosity and mobility for true fluids was obtained at various temperatures, using oils of much higher viscosities.

The apparatus is described below.

A p p a ra tu s

In order to obtain flexibility and, a t th e same time, accurate tem perature control, th e barrel of the mobilometer was provided with a brazed outer brass jacket about 0.5 inch wide fitted with outlets a t the top and bottom . These outlets are connected by means of rubber tubing to th e circulation outlets of a Hoeppler (5) therm ostat which is capable of controlling the tem perature to within =*=0.0 2° F. This apparatus provides a very flexible control of the tem perature and, by using th e proper circulation fluid and regulator in the Hoeppler therm ostat, it is also suitable for low-tem perature work, as shown by the authors in a previous article (/). The necessity of immersing th e whole mobilometer in a bath is thereby avoided, which is an im portant advantage when working a t extreme tem peratures.

Timing in this laboratory is obtained by Veeder-Root magnetic counters, reading directly in ten th seconds. These are run by a contactor connected to an American Time Products constant- frequency generator. This generator, which is run by th e plant power, allows a fluctuation of ± 1 0 volts and a frequency varia­

tion of ± 2 cycles in the current. Under these conditions the frequency does not vary by more than =“=0.001 cycle. This ar­

rangement has given complete satisfaction, the frequency fluctua­

tions having seldom exceeded th e above limits. A more com­

plete description of this equipment will be published in th e near future. Viscosities were carried out by means of Ubbelohde (7) suspended level viscometers. A No. 4 capillary (constant C — 10.04) was generally used, except for the lower viscosities which were obtained with a No. 3 capillary (constant C = 1.015). The results thus obtained were in kinematic units. The absolute viscosities were calculated by multiplying th e kinematic results by the density (obtained by pycnometer) of th e individual samples a t the various temperatures. The above procedure will give kinematic viscosities within ±0.2 per cent while th e densi­

ties were accurate to about 0.001. Tne constant-tem perature bath used for the determination of kinematic viscosities can be controlled to within ±0.0 2° F.

R e su lts

The choice of materials available for the determination of viscosities by means of viscometers of the glass capillary type is limited by the following considerations:

1. The m aterial m ust have true viscous flow—i. e., the rate of shear should be proportional to the shearing stress.

2. I t m ust be a true solution, absolutely free of suspended particles.

3. I t m ust be transparent, so th a t a sharp meniscus can be seen when determining th e viscosity.

The heaviest Pennsylvania bright stock available had a viscosity of about 163 poises at 77° F. In order to obtain high viscosities, especially at the higher temperatures, it was necessary to prepare blends of the above mineral oil with various amounts of an isobutylene polymer of very high molecular weight. Thus viscosities as high as 800 poises at 77° F. and 300 poises at 150° F. were obtained. Determina-

F IG U R E I

CORRELATION CF GARDNER MOBILOMETER TIME WITH ABSOLUTE VISCOSITY

LEGEND 7 7 °F. —

100 °R —

13 0 — 150 °F.—

2 1 0 ° F —

HOLE 01 SC.

5 1 - H O LE O IS C

2 6 00

tions of both viscosities and mobilities were carried out at 77°, 100°, 130°, 150°, and 210° F. Mobilities were also carried out with both a 51-hole and a 4-hole disk. The results are shown in Figure 1, which is self-explanatory. (Con­

centric rings indicate determinations made on different materials having the same viscosities.)

C o n clu sio n s

From an examination of the curves shown in Figure 1, the following conclusions can be drawn:

The correlation between Gardner mobilometer time (in seconds) and absolute viscosity (in poises) is a straight line passing through the origin.

The above statement holds true for determinations made at various temperatures, and for different disks, although, as should be expected, changing the disk changes the slope of the curves. In other words, each disk has its own curve passing through the origin.

The results check the work and conclusions of Cornthwaite and Scofield (2) in every respect. However, the slope of the curve obtained by these authors for their 51-hole disk is not quite the same as that presented in this paper. This is due to the fact that it is mechanically impossible to manufacture disks identical in all respects; small variations in the shape of the disk as well as in the sizes and spacing of the holes will

cause changes in mobilities and thus alter the slope of the curve.

While admittedly the mobilometer is primarily a control instrument, it is susceptible of mechanical improvement. It is based on sound principles and the data presented show that it can be used for the determination of viscosity, being par­

ticularly useful for opaque materials of very high viscosities.

It is only necessary to calibrate each disk against a material of known viscosity at any given temperature, plot this point, and draw a straight line through the origin. The sizes and number of holes in a given disk can be varied at will to suit any particular case.

L itera tu r e C ited

(1) B aldeschw ieler, E . L., and Wilcox, L. Z., I n d . En q. Ch em., Anal.

E d ., 11, 221 (1939).

(2) C ornthw aite, C. R ., an d Sco6eld, F ., Sci. Sect., N a tl. P a in t, V ar­

nish L acquer Assoc., Circ. 547 (1938).

(3) G ardner, H . A., an d Parks, H . C., P a in t M frs. Assoc. U. S., Circ.

265, 414-28 (1936).

(4) G ardner, H . A., a n d V an H u eck ero th , A. W ., I n d . E n g . Ch em., 19, 724-6 (1927).

(5) H oeppler, F ., Brenn., 14, 234 (1933); Z . tech. P h ysik., 14, 165 (1933).

(6) Sw ard, G. G., an d S tew art, J. R ., Am. P a in t V arnish M frs. Assoc., Circ. 394, 317-22 (1931).

(7) U bbelohde, L., J . In st. Petroleum Tech., 19, 376 (1933).

INDUSTRIAL AND ENGINEERING CHEMISTRY VOL. 11, NO. 10

P henols in Low-Temperature Tar

T H O M A S B . S M I T H a n d L E O K A S E H A G E N

C o a l R e s e a r c h L a b o r a t o r y , C a r n e g ie I n s t i t u t e o f T e c h n o lo g y , P it t s b u r g h , P e n n a .

V

zation of bituminous coals, including resorcinol (13, 1/+), hydroquinone (18,14), catechol (1,2,3,5,9,11-17), and some of the homologs of catechol (4, 13, 14), but ratios of the dihydric to the monohydric phenols produced during car­

bonization have not been reported. This paper describes a method by which this ratio, or, more specifically, the average number of hydroxyl groups per molecule of the phenols of a tar, may be determined, and gives the results obtained by applying it to the tars produced by carbonizing several bituminous coals at temperatures from 400° to 600° C.

The usual method of analysis, which involves the double distillation of the tar and alkali extraction of the distillate in the presence of air, is not satisfactory for the determination of the quantity of dihydric phenols present in a tar, because of the instability of these phenols toward heat and oxidation, particularly in the presence of alkali. The double distilla­

tion causes sufficient decomposition of these phenols to pre­

clude the possibility of an accurate quantitative determina­

tion of their presence in the tar as originally produced. The alkali extraction of the tar distillate in the presence of air continues the decomposition to such an extent that by the time the phenols have been separated from the other con­

stituents of the tar, only a small portion of the dihydric phenols may be left. In the present method, the tar is not distilled. The quantity and type of the phenols as they exist in the whole tar, rather than in the tar distillate, are deter­

mined.

Briefly, the method consists of extracting a tar with alkali in an inert atmosphere to prevent oxidation, methylating the alkali phenolates to stabilize the hydroxyl groups, and recovering the methylated phenols. From the methoxyl percentage and average molecular weight of these latter, their average number of methoxyl groups per molecule is calcu­

lated. This value also represents the average number of hydroxyl groups per molecule of the phenols originally in the tar. From it the ratio of dihydric to monohydric phenols may be calculated, provided it be assumed th at dihydric phenols are the only polyhydric ones present.

Carrying out the alkali extraction of the tar, and the subse­

quent methylation, in an atmosphere of nitrogen was effective in preventing oxidation of the tar. When a 500° tar from a Pittsburgh Seam coal was extracted with alkali in the pres­

ence of air, an appreciable quantity of a solid decomposition product was precipitated out on the sides of the separatory funnel. When a similar extraction was carried out in an atmosphere of nitrogen, this evidence of decomposition was absent. The alkali extraction offers another difficulty, how­

ever, in that the alkaline solution dissolves not only phenols but neutral material as well, because of the solubility of hydrocarbons in the solution of alkali phenolates. This difficulty was overcome by extracting the alkali phenolate solution with benzene, again carrying out the extraction in an atmosphere of nitrogen. The benzene, however, removed not only the hydrocarbons, but also a small quantity of the phenols. These phenols were recovered by extracting the benzene solution with fresh alkali. There was slight tend­

ency for the hydrocarbons to redissolve in the alkali, as their solubility in the alkaline solution depends upon the presence of appreciable quantities of - alkali phenolates.

The methylation was effected by means of dimethyl sul­

fate, which apparently gave a complete reaction when used in

excess. The excess was destroyed with alkali, which also hydrolyzed any esters that may have been formed from the carboxylic acids in the alkali phenolate solution. The methylated tar phenols are much more stable than the cor­

responding phenols. They are not so unstable toward heat as the phenols, and show little tendency toward oxidation when standing in air. This last property made it possible to discontinue the use of an inert atmosphere as soon as the methylation was completed, and permitted the methoxyl percentage and the average molecular weight of the methyl­

ated phenols to be determined with little danger of decom­

position during the necessary handling.

Fi g u r e 1. Te m p e r a t u r e Pr o g r a m s f o r Ca r b o n i z a t i o n s i n t h e Fi s c h e r Al u m i n u m Re t o r t

The entire method was applied to a mixture made up of 2,6-xylenol, tetralin, p-cymene, n-heptane, cyclohexanol, biphenyl, o-toluidine, and acetic acid. The methylated xylenol was obtained in a pure form with a yield of better than 93 per cent of theory. The methylation step alone was checked by methylating catechol. The veratrole result­

ing amounted to 97 per cent of theory.

E x p e rim en ta l

The ta rs analyzed in this study were produced in a Fischer aluminum reto rt (10). Each charge consisted of 100 grams of the coal, ground to 20- to 60-mesh size. The retort was subjected to the tem perature programs shown by th e curves of Figure 1.

For each carbonization the sample was heated rapidly to the desired tem perature and m aintained a t this tem perature until there was no visible evidence of distillation of ta r from the exit tube of th e retort. Throughout the heating, nitrogen was passed into the retort a t a rate of 20 cc. per minute. The ta r and liquor were collected in a small side-arm separatory funnel immersed in crushed ice. As soon as a carbonization was completed, the receiver was stoppered and weighed to determine the am ount of ta r plus liquor formed. A source of nitrogen was then con­

nected to the side arm of th e receiver, and the ta r and liquor were extracted successively with 15-, 10-, and 10-cc. portions of 5.5 N potassium hydroxide. T he solution of phenolates was ex­

tracted with three 20-cc. portions of benzene, which was then extracted with two 10-cc. portions of 5.5 N potassium hydroxide.

All the extractions were carried out in an atmosphere of nitrogen.

The alkaline solutions were combined, and enough 15 iV potas­

sium hydroxide was added to make the solution 6 N , allowing for th e diluting effect of the liquor th a t was formed with the tar.

528 INDUSTRIAL AND EN G IN EERIN G CHEMISTRY VOL. 11, NO. 10

S eam

P itts b u r g h Illin o is N o. 6 H ig h S p lin t

M in e

E d e n b o rn O rie n t N o. 1 C lo -S p lin t

Ta b l e I. An a l y s e s o p Co a l s Us e d B itu m in o u s

R a n k

H ig h -v o la tile A H ig h -v o la tile B H ig h -v o la tile A

*---P ro x ir u a te A nalysis'^{I______ s} M o istu re

V o la tile F ix e d in Sam p le

m a tte r c arb o n A sh C a rb o n iz e d

% % % %

3 3 .6 5 7 .0 7 .5 1 .4

3 3 .9 5 0 .3 9 .1 8 .2

3 0 .4 5 7 .3 3 .4 3 .9

° A n aly ses of m in e a n d tip p le sam p les, c o u rte sy of U . S. B u re a u of M in es, P it ts b u r g h E x p e rim e n t S ta tio n . 6 D ry , m in e ra l-m a tte r-fre e b a sis (m in e ra l m a tte r = 1.1 tim e s a sh ).

c O rg an ic s u lfu r only, d T o t a l s u lfu r. >;i.

C H N S O

%. % % % %

8 5 .0 5 .7 1 .7 0 .7 * 6 .9

8 0 .6 6 .1 2 .1 0 .7 « 1 0 .5

8 3 .8 5 .7 1 .8 0 .0 d 8 .1

Ta b l e II. An a l y s e s o f Ta r s Pr o d u c e d i n Fi s c h e r Re t o r t C arb o n iz in g te m p e ra tu re , ° C.

T a r y ield , g ra m s“

L iq u o r yield , g ra m s“

M e th y la te d p h en o ls, y ield , g ram a“

M e th y la te d p h en o ls, % M eO M e th y la te d phenols, m o lecu lar w eight A v erag e h y d ro x y ls p e r p h en o l m olecule D ih y d ro x y c o m p o u n d s in p h en o ls, % P h en o ls, y ield , g ra m s“

P h en o ls, y ield , % of ta r P h e n o lic oxygen, g ra m s0

O rganio oxy g en in 100 g ram s of coal, gram s Ph cn o lio oxygen, % of o rg an ic oxygen

“ F ro m 100 g ram s of coal.

.--- H ig h S p lin t C o al---n

<nn enn 400

5 .0

—E d e n b o rn C o a l -

500 600

1 4 .5

.--- Illin o is N o . 6 C o al---

A n n e r t n 600

1 2 .9

8 .3 1 6 .5 1 6 .2 1 4 .2 1 3 .8 6 .2 6 .4 1 3 .4 1 3 .5

5 .6 6 .2 6 .1 2 .3 3 .9 3 .8 3 .7 1 1 .0 11 .4 1 1 .2 1 1 .2 1 3 .2

2 .0 4 .7 4 .7 0 .6 3 .7 3 .4 3 .6 2 .6 2 .9 5 .0 5 .1 5 .4

1 7 .5 0 1 7 .8 6 1 7 .9 6 18.5 3 1 6 .8 9 1 6 .8 6 16.7 2 2 2 .2 3 2 1 .8 4 1 9 .1 0 1 8 .9 8 2 0 .7 6

192 181 181 207 206 207 202 173 174 165 168 154

1 .0 8 4 1 .0 4 3 1.0 4 9 1 .2 3 7 1 .1 2 3 1 .1 2 7 1.091 1.2 4 1 1 .2 2 7 1 .0 1 7 1 .0 2 9 1.0 3 1

8 .4 4 .3 4 .9 2 3 .7 1 2 .3 1 2 .7 9 .1 24 .1 2 2 .7 1 .7 2 .9 3 .1

1 .8 4 .3 4 .3 0 .5 5 3 .4 3 .1 3 .3 2 .3 2 .6 4 . 6 4 .7 4 .9

2 1 .7 2 6 .0 2 6 .5 1 1 .0 2 4 .0 2 2 .4 2 2 .8 3 7 .1 4 0 .6 3 4 .3 3 4 .8 3 8 .0

0 .1 8 2 0 .4 3 3 0 .4 3 5 0 .0 5 7 0 .3 2 2 0 .2 9 6 0 .3 1 1 0 .2 9 8 0 .3 2 6 0 .4 9 4 0 .5 0 0 0 .5 7 9

7 .5 0 6 .3 4 8'. 68

2 .4 5 .8 5 .8 0 .9 5 .1 4 .7 4 .9 3 .4 3 .8 5 .7 5 .8 6 .7

The benzene extraction of the plienolate solution was neces­

sary because of the high solubility of hydrocarbons in the phenol- ate solution. In one case the weight of neutral m aterial dis­

solved by the alkali was 40 per cent of the weight of the phenols dissolved. The quantity of phenols redissolved by the benzene was small, b u t these phenols were lower in molecular weight than those remaining in the alkaline solution, so th a t it was necessary to recover them in order to get a true picture of th e average composition of all the phenols.

M éthylation was carried out by adding the alkali phenolate solution slowly to a stirred m ixture of dimethyl sulfate and benzene held a t about 70° C. The quantity of dim ethyl sulfate used was about 50 per cent in excess of th a t required to convert all the alkali to potassium m ethyl sulfate. Initial heating only was necessary, as the reaction was exothermic. Once th e reaction was started, the tem perature could be regulated by means of the rate of addition of alkali phenolate solution. After this solution had been completely added, twice the am ount of 15 N potassium hydroxide equivalent to th e remaining dimethyl sulfate was added to the hot m ethylating mixture. After the destruction of the excess dimethyl sulfate, two layers remained. The aqueous layer contained the salts of the carboxylic acids originally in the tar, and the benzene layer the m ethylated phenols. This layer was washed several times with alkali and water, and dried, and the benzene was removed by distillation followed by evacuation.

Them ethoxyl percentage of the m ethylated phenols was de­

termined by a modified Viebôck micromethod. Analyses for sulfur were made to ascertain whether the dimethyl sulfate, which would raise th e methoxyl percentage, had been com­

pletely removed from the m ethylated phenols. Their average molecular weight was determined cryoscopically using biphenyl as a solvent. A pparent molecular weights were determined for several different concentrations, and the value obtained by extrapolating to zero : concentration taken as th e true average molecular weight. The molecular weights of several pure aro­

matic ethers were determined by this m ethod with errors of less than 2 per cent, and checks within 4 per cent were obtained on th e m ethylated phenols from th e tars.

Analyses of the coals used are shown in Table I. The Pittsburgh Seam coal is a high-volatile A coking coal, the Illinois No. 6 coal is high-volatile B and has a high oxygen content, which barely falls within the limits for coking coals.

The High Splint coal is likewise high-volatile, but in contrast to the other two is dull and contains a high percentage of attritus.

Table II gives the results of the analyses of the tars pro­

duced under the indicated conditions from the various coals.

Yields of tar and liquor were determined in separate car­

bonizations, as no separation of tar from liquor was made dur­

ing the analyses. The average numbers of hydroxyl groups per phenol molecule were calculated from the methoxyl percentages and average molecular weights of the methylated

phenols, shown just above in Table II. The percentages of the phenols which are dihydric, assuming that there are no trihydric or higher phenols present, follow directly. This assumption is based on the facts that the probability of forming trihydric phenols is much lower than that of forming dihydric phenols, and that the presence of trihydric phenols in tar has never been reported. The yields of phenols, as calculated from the experimentally determined yields of methylated phenols, and the phenolic oxygen, as per cent of the organic oxygen in the coal, are also shown in Table II.

D is c u s sio n o f R e su lts

The high ratios of dihydric to monohydric phenols in the tars made from Edenborn coal are the most striking feature of the results. The ratio decreased as the temperature of carbonization was raised (see Figure 2). This change may be accounted for if the known instability toward heat of the dihydric phenols is considered. The tendency to produce oxygenated compounds high in polyhydric phenols appears to be characteristic of this Pittsburgh Seam coal. This tendency, however, cannot be linked to the classification of the coal, on the basis of the present data. The High Splint coal, which differs from Edenborn coal mainly in that it is a dull instead of a bright coal, gave less than half the yield of dihydric phenols th at was obtained from Edenborn coal.

The Illinois No. 6 coal, because it has a higher oxygen con­

tent, might be expected to produce phenols having a larger average number of hydroxyl groups per molecule than those from Edenborn coal. The increased oxygen content might increase the probability of two oxygen atoms being attached to the same nuclear grouping. However, when the size of these nuclear groupings as possibly indicated by the molecular weights of the phenols produced from the two coals is con­

sidered, these probabilities for the two coals are not so very different. The nuclear groupings in Edenborn coal must definitely be larger than those in the Illinois coal because the molecular weights of the phenols from Edenborn coal, as calculated from the experimentally determined molecular weights of the methylated phenols, are close to 190, while those from the Illinois coal are only 150. This difference in nuclear size almost compensates for the effect of the difference in oxygen contents when considering the probability of having two oxygen atoms linked to the same nucleus. The higher oxygen content of the Illinois coal is, however, reflected by

ANALYTICAL EDITION 529 the increased productions of phenols, and by the fact th at

the phenolic oxygen from the Illinois coal represents a larger percentage of the organic oxygen of the coal than is the case with the phenols from Edenborn coal.

The very sharp drop from 23.4 to 2.3 in the percentage of dihydric phenols in the total phenols, as the temperature of carbonization was raised from 400° to 500° C., for the Illinois coal may perhaps be explained on the basis of the instability toward heat of the dihydric phenols. However, this drop in the same temperature interval for the dihydric phenols from Edenborn coal was only from 23.7 to 12.5 per cent.

Thus it may be assumed that the dihydric phenols produced from the two coals are different. These phenols are not uni­

form in their stability toward heat. For example, of the three dihydroxybenzenes, the meta compound is decomposed more rapidly than either of the other isomers, when pyrolyzed at 350° C. (18). If the oxygen distribution in Illinois coal is such that only very thermally unstable dihydric phenols can be produced, then only a very low temperature of car­

bonization will permit this production to take place.

In Table II I is given a comparison between the yields of phenols obtained by the Bureau of Mines (7, 8) using a standard method of analysis (6), and the yields obtained by the method described in this paper. The latter are uni­

formly higher than the ones given by the standard method, and indicate that appreciable amounts of the phenols origi­

nally present in the tar are either destroyed during the stand­

ard analysis, or else remain in the pitch, since in the standard method only the phenols in the tar distillate are determined.

Ta b l e III . Co m p a r i s o n w i t h Re s u l t s o f St a n d a r d Me t h o d o f An a l y s i s

4 0

1 0 ( 0

* i 30

Z Q .

y(2cc

a ^

1°. 'O

a PiTT S B U R G H COAL L IN 0 I5 NO. 6 COA g h Sp l i n t Co a l

t

o I I A Hi

k -

L

"--- i

r N r ~ 1

Ca r b o n i z i n g Te m p e r a t u r e

Fi g u r e 2 . Co m p o s i t i o n o f Ph e n o l s a s a Fu n c t i o n o f Ca r b o n i z i n g Te m p e r a t u r e

This conclusion is open to the objection th at the tars made by the Bureau of Mjnes, and those studied in this investiga­

tion, were produced in different types of retorts and therefore are not necessarily similar. For this reason, the phenols in a 500° tar from Edenborn coal were determined by the three methods indicated in Table IV with the results there given.

I t is clearly shown th at the method described in this paper (method 1) does give higher yields of phenols than the stand­

ard method (method 3). The results given by method 2 show th at most of the decomposition of phenols in the stand­

ard method of analysis occurred during the double distillation.

Not only was the quantity of phenols in the distillate smaller than th at in the crude tar, but the nature of the phenols was also quite different. For example, in the crude tar the phenols had an average molecular weight of 213 and an av­

erage of 1.04 hydroxyls per molecule, while in the distillate obtained by the double distillation of the crude tar, they had an average molecular weight of only 149 and an average of 1.02 hydroxyls per molecule.

P itts b u r g h

C oal Illin o is N o. ( C oal T e m p e ra tu re of c a rb o n iz a tio n , 0 C.

T a r acids b y s ta n d a rd m e th o d , % of d ry t a r

P h e n o ls b y m e th o d describ ed in th is p a p e r, % of d ry ta r

500 000 500 600

1 7 .4 1 5 .8 2 9 .8 3 0 .0

2 3 .2 2 2 .8 3 4 .5 3 8 .0

Ta b l e IV. Ph e n o l s i n a500° Ta rf r o m Ed e n b o r n Co a l Y ield of P h en o ls, A v erag e A verage N u m b e r

P e r C e n t of M o leo u lar W eig h t of H y d ro x y ls D ry T a r of P h e n o ls p e r M olecule M e th o d 1°

M e th o d 2 b M e th o d 3 C

2 0 .7 15 .1 14 .2

213

149 1 .0 4

1.02

a A lk ali e x tra c tio n of c ru d e t a r in ab sen ce of air, follow ed b y m é th y la tio n of p h e n o la te so lu tio n .

o D o u b le d is tilla tio n of c ru d e ta r, w ith d is tilla te tre a te d as in m e th o d 1.

c D o u b le d is tilla tio n of cru d e ta r , w ith t a r acid s in d is tilla te d e te rm in e d b y c o n tra c tio n on s h a k in g w ith alk ali.

S u m m a r y

A method for determining the quantity and average num­

ber of hydroxyl groups per molecule of the phenols of a low- temperature tar has been developed and applied to tars made from several bituminous coals at temperatures from 400° to 600° C. The results on a tar from a Pittsburgh Seam coal show th at this coal yields tar containing large amounts of dihydric phenols. Results on tars from Illinois No. 6 coal show that this coal can also yield tars containing large quan­

tities of dihydric phenols if the carbonization temperature is kept sufficiently low, but that as the temperature is increased these dihydric phenols are not found in the tar, probably because of their instability toward heat.

Yields of phenols obtained by this method are higher than those obtained by the standard method of analysis, because of decomposition during the double distillation, and probably also because of failure of the phenols in the crude tar to dis­

till at the temperatures reached in the distillation.

L ite r a tu r e C ited

(1) B ornstein, E ., J . Gasbeleucht., 49, 627-30, 648-52, 667-71 (1906).

(2) B ritta in , A., Rowe, R . M ., an d S in n a tt, F . S., Fuel, 4, 263-9, 299-307, 337-40 (1925).

(3) B row n, R . L ., an d B ran tin g , B . F ., In d. En o. Ch e m., 20, 392 (1928).

(4) B urke, S. P ., an d C aplan, S., Ibid., 19, 34-8 (1927).

(5) E dw ards, K . B „ J . Soc. Chem. In d ., 43, 149T (1924).

(6) Fieldner, A. C., D avis, J . D ., Thiessen, R ., K ester, E . B., and Selvig, W . A., U. S. B ur. M ines, B ull. 344 (1931).

(7) Ib id ., 525 (1932).

(8) Fieldner, A. C., D avis, J . D ., Thiessen, R ., K ester, E . B., Selvig, W . A., R eynolds, D . A., Ju n g , F . W ., an d S prunk, G . C., U. S. B u r. M ines, Tech. P aper 524 (1932).

(9) Fischer, F ., Brennstoff-Chem., 1, 31, 47 (1920).

(10) Fischer, F., and Schrader, H ., Z . angew. Chem., 33, 172 (1920).

(11) G luud, W ., and B reuer, P ., Ges. Abhandl. K en n tn is Kohle, 2, 236 (1917).

(12) H eym ans, J. W ., Chimie & industrie, 23, 1120 (1930).

(13) M organ, G . T ., Fuel, 10, 183-9 (1931).

(14) M organ, G. T ., an d P e tte t, A. E . J ., J . Soc. Chem. In d ., 50, 72T (1931); 56, 109T (1937).

(15) M organ, G. T ., P r a tt, D . D ., an d P e tte t, A. E. J., Ibid., 48, 89T (1929).

(16) M organ, J . J., an d Soule, R . P ., Chem. M et. E ng., 26, 923 (1922).

(17) P arish , E ., an d Rowe, R . M ., J . Soc. Chem. In d ., 45, 99T (1926).

(18) S m ith, T . B., and K asehagen, L., unpublished w ork.

Pr e s e n t e d b efo re th e D iv isio n of G as a n d F u e l C h e m istry a t th e 9 7 th M e e tin g of th e A m e ric a n C h em ical Society, B altim o re , M d .