Industrial and Engineering Chemistry : analytical edition, Vol. 18, No. 8

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INDUSTRIAL ^{a n d} ENGINEERING CHEMISTRY

A N A LY TICA L ED ITIO N

V O L U M E 18, N U M B E R 8 IS S U E D A U G U S T 16, 1946 C O N S E C U T IV E N U M B E R 16

Assistant to Editor: N . A . P A R K I N S O N

Manuscript Editing: G . G L A D Y S G O R D O N

R. P. C H A P M A N J . R. C H U R C H IL L B. L . C L A R K E

E D IT O R : W A L T E R J. M U R P H Y Associate Editor: La w r e n c e T. Ha l l e t t

Assistant Editors

Manuscript Reviewing: S T E L L A A N D E R S O N

A dvisory Board

T . R. C U N N I N G H A M G . E . F. L U N D E L L M . G . M E L L O N

C ontributing E d ito r: R. H . MÜLLER

M ake-up: CH ARLO TTE C . SAYRE

R. H . M U L L E R S . L . O S E R H . H . W IL L A R D

Applications of Infrared Spectroscopy to D D T ...

J . R. Downing, W . V . Freed, I. F. W alker, and G . D. Patterson 461 Routine A n alysis of Sodium-Potassium A llo y s ...

S. L. Walters and R. R. M ille r 468 Determination of Ethylene Chlorohydrin . . . Karl Uhrig 469 Colorimetric Determination of Local A nesthetic Compounds

F. J . Bandelin and C . R. Kemp 470 Molecular W eight and Mercaptan Content of Mixtures of

Primary Mercaptans . . H . A . Laitinen, A . S . O ’Brien, and J . S. Nelson 471 Determination of A c id in Presence of A lu m in u m ...

R. P. Graham 472 Colorimetric Determination of Cobalt in Metallurgical Prod

ucts with Nitroso R Salt . . . R. S. Young, E. T. Pinkney, and R. Dick 474

Radioactive Studies

Radioactive Isotope Dilution P r o c e d u r e s ...

F. C . Henriques, J r ., and Charles Margnetti 476 Analytical Chemistry of Rare E a r t h s ...

G . L. Barthauer and D. W . Pearce 479 Estimation of Ammonium Picrate in Wastes from Bomb- and

Shell-Loading Plants. . .C . C . Ruchhoft and F. I. Norris 480 Determination of Hiding and Contrast-Obliterating Power of

P a i n t s ... P. F. Luft 484

Nomographic Procedure for Two-Component Colored

. S y s t e m E. A . Brown 493

Differential Reduction of Iron and T i n ...

A . C . Simon, P. S. M ille r, J . C . Edwards, and F. B. Clardy 496 Detection of Elemental Sulfur in Gasoline by Sommer Test

G . E. Mapstone 498 Q ualitative Test for Carbohydrate M a t e r i a l ...

Roman Dreywood 499 M IC R O C H E M IS T R Y

Determination of Ethers and Esters of Ethylene G ly c o l . . P. W . Morgan 500 Precision Semimicromethod for G as A n alysis . . . . .

’ , L. K. Nash 505

Determination of N icotine in A i r ...

W . E. M cCormick and M axine Smith 508 Nitrogen Determination by Micro-Dumas M ethod . . .

Ervin Stehr 513 Identification of Organic Bases by Means of O p tical

Properties of Diliturates (N itro b arb itu ra te s)...

B. T. Dewey and E. M . Plein 515

N O T E S O N A N A L Y T I C A L P R O C E D U R E S

Modification of A rsen ic M ethod of Magnuson and Watson • • • • • • • . . . . , , , ,T . H . Maren 521 Determination of Free Carbon in Butyl Reclaim by

M odified A .S .T .M . M ethod . ... . J . E. M cC ready and H . H . Thompson 522 Instrumentation in A n alysis . . R. H . M üller (A d v t. Sect.) 23

Hie ^Afrrerican Chem ical S o c ie ty assumes no re sp o n sib ility fo r the statements and opinions advanced by contributors to its p u b licatio n s. V i e w s expressed in the editorials are those o f the editors and d o not n ecessarily represent the o fficia l position of the Am erican Chem ical So cie ty.

W e a ck n o w le d g e w ith thanks the action o f J . T . Baker C he m ical C o . in releasing the front c o v e r o f this issue fo r edito rial purp oses.

C o p yrig h t 1 9 4 6 by. Am erican C hem ical S o cie ty.

3 6 ,8 0 0 co p ie s o f this issue p rin te d.

Published b y the A m erican C hem ical S o cie ty at Easton, Pa. E d ito rial H e a d quarters: 1 1 5 5 16 th S tre e t, N . W ., W ash in gto n 6 , D . C . ; te le p h o n e . R ep u b lic 5 3 0 1 / cable, Jiech e m (W a sh in g to n ). N e w Y o rk E d ito ria l Branch: 6 0 East 4 2 n d S tre e t, N e w Y o rk 1 7 , N . Y .» te le p h o n e , M u rray H ill 2 - 4 6 6 2 . C h ic a g o E d ito ria l Bran ch : poom 8 1 9 , 2 5 East Jack so n B lv d ., C h ic a g o 4 , III./ te le p h o n e , W abash 7 3 7 6 . Business y r f ic e : A m e rican C he m ical S o c ie ty , 1 1 5 5 16 th S tre e t. N . W ., W ashington 6 , D . C . Advertisin g O f f ic e : 3 3 2 W e st 4 2 n d Stree t, N e w Y o rk 1 8 , N . Y ./ te le p h o n e , Bryant 9 - 4 4 3 0 .

Entered as second-class matter at the Post O ff ic e at Easton, P a ., u n der the A c t o f March 3 , 1 8 7 9 , as 2 4 times a ye ar— Industrial E d itio n m onthly on the 1 st, A n a ly tic a l tajtio n monthly on the 1 5 th . A c c e p ta n c e fo r m ailing at spe cial rate o f postage p ro vided fo r in Se ctio n 1 1 0 3 , A c t o f O c to b e r 3 ,1 9 1 7 , au th o rized J u ly 1 3 ,1 9 1 8 .

f , j Cm^t<jnces o rders fo r subscriptions and fo r sin gle co p ie s, notices o f changes or address and n e w p rofessio nal con nection s, and claims fo r missing numbers should sent to the A m e rican C hem ical S o c ie ty , 1 1 5 5 16th S tre e t, N . W ., W ashington 6 ,

D. C . C hanges o f address fo r the Industrial E d itio n must be re ceive d on o r b efore the 18th o f the p rece d in g month and fo r the A n a ly tic a l E d itio n not later than the 30th o f the p rece d in g month. Claim s fo r missing numbers w i l l not be a llo w e d ( 1 ) if re ceive d more than 6 0 days from date o f issue (o w in g to d e liv e ry hazards, no claims can be h o nored from sub scrib ers in C o n tin e n tal E u ro p e , A s ia , o r the P a cific Islands o th e r than H a w a ii) , ( 2 ) if loss w a s due to failu re o f no tice o f change o f address to be re ceive d befo re the dates sp e cifie d in the p rece d in g sentence, o r ( 3 ) if the reason fo r claim is ' missing from files .

A n n u a l subscriptions— Industrial E d itio n and A n a ly tic a l Ed itio n sold o n ly as a u n it, members $ 3 .0 0 , nonmembers $ 4 .0 0 . Postage to cou ntries not in the Pan- A m e rica n U n io n $ 2 .2 5 / C an ad ian postage $ 0 .7 5 . S in g le co p ie s— cu rrent issues, In du strial E ditio n $ 0 .7 5 , A n a ly tic a l E ditio n $ 0 .5 0 / back numbers, Industrial Edition

$ 0 .8 0 , A n a ly tic a l Ed itio n p rices on request/ sp e cial rates to members.

The A m erican C hem ical S o c ie ty also publishes C h e m ica l a n d E n g in e e rin g N ews C h e m ic a l A b s tr acts, and J o u r n a l o f the A m e rica n C h e m ic a l S o c ie ty . Rates on request.

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T HANK C HE MI C A L R E S E A R C H . . .

for the widened use o f alloys!

O ut o f chem ical research fo r w ar needs th e re has com e th e w id en ed use o f alloys.

For specialty steel m akers have been called u p o n to develop m etals w ith specific p r o p erties to do unusual jobs.

As a resu lt w e have today alloys th at are lig h te r, stro n g e r, and w ith m any qualities lo n g h o p e d fo r but never previously achieved. T h e w id en ed use o f alloys — the resu lt of m any new ly disco vered p r o p e rtie s — is a trib u te to chem ical research.

T h a n k th e chem ist also fo r his c o n tro l m eth o d s to assure ex actin g uniform ity o f quality.

B ak er’s Analyzed C. P. C hem icals and A cids are to o ls used by the chem ist both fo r p ro d u c t rese a rc h o f alloys an d for th e ir quality co n tro l. T h e se lab o ra to ry re

agents are the choice o f the n a tio n ’s finest chem ists and are sto ck ed by the lead in g la b o ra to ry supply h ouses o f the country.

H e re ’s the reason. T hey are dependable.

T hey b ear the actual analysis on the label, w hich enables th e chem ist to save time and o b tain accurate results. So o n your n ex t o rd e r specify B ak er’s A nalyzed w hen you send your o rd e r to your favorite lab o rato ry supply house.

J . T. B a k e r C h e m i c a l C o . , E x e cu tiv e O ffice s and Plant: P h i l l i p s b u r g , N . J . Branch O ffic e s : N e w Y o r k , P h i l a d e l p h i a , B o s t o n a n d C h i c a g o .

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L E E D S & N O R T H R U P C O M P A N Y , 4920 S T E N T O N A V E ., PH I L A . 44, P A .

LE E D S & N O R T H R U P

M E A S U R IN G IN S T R U M E N T S • T E L E M E T E R S • A U T O M A T IC C O N T R O L S • H E A T - T R E A T I N G F U R N A C E S I r l . A d E - 3 3 C - 4 6 0 C 1 )

A ugust, 1946 A N A L Y T I C A L E D I T I O N

A CHEMI CAL’S PURITY

Can Often Be Checked With An L & N

MUELLER BRIDGE

Principal elements of Mueller Bridge, Type G-2, for meas

uring tem perature to highest precision.

Beginning a t top are: The Bridge proper, its Platinum Resistance Therm om eter Bulb, and the Type H . S.

Galvanometer and Scale usually employed.

Not shown are the m irror and prism often used with Galva

nometer, and the Bridge’s Calibrating Resistor.

Petroleum research employs this Mueller Type G-2 Thermom eter Bridge a t Ohio State University.

When the purity of a chemical can be reliably indicated by its freezing or boiling tem perature, there are several good reasons for determining this tem perature with an L & N Mueller Bridge:

A ccu racy . The Bridge measures tem perature in terms of the resistance, in ohms, of a nominal 25-ohm resistance thermometer. Its limit of error is a few hundred-thousandths of an ohm, or a few parts per million, whichever is the larger.

Between —190 and + 5 0 0 C, this is the highest accuracy attainable with any com

mercial equipment.

E ase of A p p lic a tio n . The equipment is a specialized W heatstone bridge. It can be used without precaution against ambient tem perature, and this fact, together with its extremely complete and convenient dials, switches and other adjustm ents, makes it unusually easy to operate.

Catalog E-33C(1), describing the Mueller Bridge, is free on request.

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I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y Vol. 18, No. 8

Good News for laboratories About

PYREX FRITTED GLASSWARE

B R A N D

;‘P y r e x ” F ritte d G la s s w a re is n o w a v a ila b le at y o u r L a b o r a to ry S u p p ly D e a le r ’s.

H e c a n p ro v id e .a ll th e ite m s y o u n e e d in th is n e w e s t a id to c h e m ic a l filtra tio n . I n tr o d u c e d in 1940 , P y re x b r a n d F ritte d G la s s w a re b r o u g h t n e w sp e e d , re te n tiv ity , f re e d o m fro m c h e m ic a l r e a c tio n a n d p r e c is io n p o r o s ity c o n tr o l to filtra tio n , e x tr a c tio n a n d d is p e r s io n . G la s s p a rtic le s o f u n ifo r m size, m a d e fro m P y re x b r a n d C h e m ic a l G la s s N o . 774 , a re f ritte d by a s p e c ia l p r o c e s s a n d se ale d in to tr a n s p a r e n t b o d ie s — cells, b e a k e rs , c ru c ib le s , tu b e s , e tc .—

fa b r ic a te d fro m th e sam e g la ss. N o flux o r g la z in g m a te ria l is used.

Five p o r o s itie s , fro m u ltr a fine to e x tra c o a rs e , c o v e r p ra c tic a lly every p o s s ib le re q u ir e m e n t. F iltra tio n , e x tra c tio n a n d d is p e r s io n a re c o m p le te ly v isib le at a ll tim e s a n d th e g l a s s — b o th d isc a n d b o d y —is n o t affected by s o lu tio n s w h ic h d e s tro y o th e r filte rin g m e d ia . L o n g life is a s s u re d s in c e P y re x F ritte d W a re is re a d ily c le a n e d w ith w a te r o r c h e m ic a ls — m ay b e h e a te d in an e le c tric fu rn a c e to x i 5 °C. P y re x F ritte d G la s s w a re is d e s c r ib e d in P a r t I I I o f C a ta lo g L P 24 .

C o n s u lt y o u r r e g u la r la b o r a to r y su p p ly d e a le r f o r d e liv e ry d ata.

"P yrex” is a registered trade-m ark a n d indicates m anufacture by

C O R N I N G G L A S S W O R K S « C O R N I N G , N E W Y O R K

pyR C X

B A L A N C E D F O R A L L - A R O U N D U S E

PYREX

b r a n d L A B O R A T O R Y C L A S S W A R B

m eans ---

Research in Glass

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A ugust, 1946 A N A L Y T I C A L E D I T I O N 7

'ePf- ÓM for

1

this proven aescript;Ve ,itera an°lytical tool

THE CONSOLIDATED MASS SPEC TRO M ETER

has the efficiency an d a c cu ra cy needed for fast a n a ly sis of com plex m ixtures—

com pletes most a n a ly se s in less than an hour—a n a ly ze s m ore sam p les in less m an hours a t low est cost.

HERE ARE THE EXTR A SER V IC ES

w h i c h p r o v i d e g r e a t e r s c o p e , m o r e u s e a b l e d a t a , b e tt e r r e s u lt s .

-jSr

A d d itio n a l F a cilitie s

and advanced operating techniques furnish a complete analytical process which adds greatly to the value of the Mass Spectrometer.

■¥•

In s ta lla tio n S u p e rv is io n

is provided by a Consolidated specialist.

O p e r a t io n In stru c tio n

— one of Consolidated's graduate engineers furnishes complete instruction in the instrument's use, main

tenance, analysis theory and practice.

As Consolidated's interest in the user and his problems includes continued development of both the instrument and its application to all analysis problems, consultation service is alw ays availab le on routine work and special questions.

CONSOLIDATED EN G IN EERIN G CORP.

6 2 0 N. LAKE AVEN UE" ^PASADENA 4, CALIF.

Manufacturers of M ass Spectrom eters, Vibration and Strain Analysis and Recording Equipment

/ D R O V E H

w h i c h p r o v i d e s ^ _ M .| t a t W e a n a l Y * 1 5 '

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8 I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y Vol. 18, No. 8

C e n t r a l S c i e n t i f i c C o m p a n y

S c ie n t if ic CfflQ) ■OjfijQcLXatuii

N e w York B O ST O N S o n 'T ran cisco C H IC A G O Los A n g e le s T O R O N TO M o n tre a l.- V is it our Booth N o. 71

National Chemical Exposition Chicago Coliseum

SERVING SCIENCE

F o r a s s u r a n c e o f p r o d u c t , p r i c e a n d s e r v ic e — s p e c ify C e n c o . T h e C e n tr a l S c ie n tific C o m p a n y , e s t a b li s h e d in 1 8 8 9 , is k n o w n i n t e r n a t i o n a l l y f o r th e m a n u f a c tu r in g a n d m e r c h a n d i s in g o f s c i e n tific in s tr u m e n ts a n d a p p a r a t u s f o r e d u c a t io n a l, i n d u s t r i a l a n d c lin ic a l l a b o r a t o r i e s . C e n c o ’s c o m p le te s to c k s f a c i li ta t e te s ti n g o f a ll ty p e s :

C o a l a n d C o k e P a in ts, V a r n is h e s , etc.

D a ir y P ro d u c ts P a p e r

F e rm e n ta tio n In d u s t r ie s P e tro le u m P ro d u c ts F o o d a n d D r u g s R u b b e r

H i g h w a y T e stin g S o ils a n d Fe rtilize rs

Leather a n d G lu e T e x tile s

M e t a ll u r g y V e g e t a b le O ils , S o a p M illin g , B a k in g , G r a in s W ate r a n d S e w a g e

A p p a r a tu s m a n u f a c tu r e d b y a n d b e a r i n g th e fa m o u s C e n c o t r a d e m a r k in c lu d e : D e K h o t i n s k y d r y i n g o v e n s , i n c u b a t o r s , t h e r m o r e g u l a t o r s , " P h o t e l o m e t e r s ” a n d " S p e c t r o p h o t e l o m e t e r s ,” H y v a c , P re s - s o v a c , M e g a v a c , H y p e r v a c a n d S u p e r v a c p u m p s , T e n s i o m e t e r s , H y d r o p h i l b a la n c e s , etc. C e n c o a l s o d i s t r i b u t e s i n t e r n a t i o n a l b r a n d s :

B a k e r 's A n a l y z e d C h e m ic a ls • C o o r s P o r c e la in w a r e

" P y r e x ” a n d " V y c o r ” B r a n d G l a s s w a r e • N o r m a x , E x a x a n d R e s is t a n c e G la s s w a r e • Leco C a r b o n a n d

S u lp h u r D e te rm in a to rs • W a r in g B le n d o r s

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1 I; B. F. Goodrich Chemical Company

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Available i n c o m m e r c i a l q u a n t it ie s

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For additional information p lease w rite B. F. Goodrich Chemical Company, Departm ent C A - 8 , Rose Building, Cleveland 1 5 , Ohio.

B. F. G oodrich C hem ical C om pany

A DIVISION O f THE B. F. G O O D R IC H C O M P A N Y

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Timely REINHOLD Books

THE ALKALIN E EARTH AND HEAVY M ETAL SO A PS

by S T A N L E Y B . E L L I O T T , A s s ’t to t h e P re s id e n t, T h e F e rro C h e m ic a l C o rp . S u b s id ia r y of F e rro E n a m e l C o r p ., C le v e la n d , O h io

tr e a tm e n t o f th e s u b j e c t, six a p p e n d ic e s o n p a te n ts , sp e c ific a tio n s an d a p p lic a tio n s arc in c lu d e d , g r e a tly in c r e a s in g th e p r a c tic a l v a lu e o f th e b ook .

In Ib is ca p a b ly w r itte n a n d th o r o u g h -g o in g tr e a tise o n m e t a llic so a p s, fa t t y a c id s , n a p h th e n ic a c id s , d r y in g o ils , a n d r e s in s are d is c u sse d b o th in d i

v id u a lly a n d in c h e m ic a l c o m b in a tio n w ith e ig h t d ifferen t g ro u p s o f m e t a ls . T h e u s e s o f th e s e so a p s h a v e b een d iv id ed in t o th r e e c la s s e s , b a sed r e sp e c  tiv ely on t h e c a tio n , on th e a b ilit y to in flu e n c e th e c h a r a c te r istic s'o f liq u id s , a n d o n th e p h y sic a l p rop er

tie s o f th e in d iv id u a l so a p . In a d d itio n to th e m a in 340 Pages

N o o th e r h ook in E n g lis h b r in g s all th is diversified in fo r m a tio n to g e th e r for rea d y referen ce; t h is m o n o  g ra p h w ill th e r e fo r e h e a n e c e s s ity for a ll w ork ers in th e field s w h ic h it co v ers, a n d a n e s s e n tia l a d d itio n to th e lite r a tu r e o f te c h n ic a l lib ra ries.

P ric e $7.50 Illu s t r a t e d

A m e ric a n C h e m ic a l S o c ie ty M o n o g rap h No. 103

B IO CH EM ISTR Y OF TH E FATTY ACIDS and their compounds, the Lipids

B y W . R . B L O O R , P ro fe sso r of B io c h e m is t r y a n d P h a rm a c o lo g y , U n iv e r s it y of R o c h e s te r d ia b e te s , s y p h ilis , a r th r itis , a n d o th e r s , is e m  p h a siz e d . In s h o r t, t h is h ook provid es a m u c h - n eed ed s t u d y o f a gro u p o f o r g a n ic c o m p o u n d s , th e fa ts , so c lo s e ly a s s o c ia te d in t h e h u m a n b o d y w ith c a r b o h y d r a te s a n d p r o te in s. It w ill be o f th e g r e a te s t v a lu e to p h y s ic ia n s , n u t r it io n is t s , o r g a n ic c h e m is t s , and b io c h e m is t s , a s w ell a s in t h e food a n d p lia r - T h is v o lu m e p r e se n ts a n e x h a u stiv e c r itic a l review

o f th e c h e m is tr y a n d f u n c t io n s o f th e im p o r ta n t g ro u p o f s iib s t a n c e s in c lu d e d in th e te r m “ fa t t y a c id s .” T h e p a rt p la y e d by faLs a n d lip id s in th e c o m p lic a te d m e c h a n is m o f d ig e s tio ii a n d n u t r it io n , as w e ll as in th e b lood a n d tis s u e s , is d is c u sse d in g rea t d e ta il. T h e r e la t io n o f fa t t y a cid m e t a b o lis m to su c h p e r tin e n t s u b j e c ts a s v it a m in s , e n z y m e s , th e r e p r o d u c tiv e c y c le , e m b o lis m , a n e m ia , cancer.

387 Pages Illu s t r a t e d

A m e ric a n C h e m ic a l S o c ie ty M o n o g rap h No. 93

m a c e u t ic a l field s. A c o m p le te b ib lio g r a p h y is given for every c h a p te r .

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T H E C H E M IS T R Y OF A C E T Y L E N E

B y J U L I U S A . N IE U W L A N D , L a t e P ro fesso r of O r g a n x C h e m is tr y , U n iv e rs ity of N otre D a m e ; and R IC H A R D R . V O G T , Professor of C h e m is tr y , U n i

v e rsity of N otre D am e

S u rv ey s th e e n tir e lite r a tu r e r e la tin g to a c e ty le n e c o m p o u n d s . M a n y y ea rs in p r e p a r a tio n , i t carries o n th e u n fin is h e d w ork o f t h e la t e F a th e r N ie u w la n d , im p o r ta n t to e a r ly d e v e lo p m e n t o f s y n t h e t ic ru b b er in U . S. F e a tu r e s d e ta ile d d is c u s s io n s o f: T h e P h y s  ic a l P r o p e r tie s, P r e p a r a tio n a n d P u r ific a tio n o f A c e ty le n e ; M e ta llo -D e r iv a tiv e s o f A c e ty le n e : S u b  s t it u t io n o f N o n -M e ta l A to m s or R a d ic a ls fo r th e H yd rogen o f A c e ty le n e ; A d d itio n o f N o n -M e ta llic E le m e n t s a n d C o m p o u n d s to A c e ty le n e ; P o ly m e r iz a  tio n o f A c e ty le n e a n d i t s C o n d e n s a tio n w it h C arbon C o m p o u n d s. In c lu d e s c o m p le te in f o r m a tio n on th e c h e m is tr y , p r o p e r tie s, a n d u s e s o f N e o p ren e.

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ANHYDROUS ALUM INUM C H LO R ID E IN O RGAN IC C H E M IS T R Y

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T h o m a s an d H o c h w a lt L a b o ra to rie s, M o n sa n to C h e m ic a l C o m p a n y

T h is v o lu m e h a s b e e n ea g erly a w a ite d fo r s o m e t im e by a ll th o s e c o n c e r n e d w ith th e c a ta ly s is a n d is o m e r iz a  tio n o f o r g a n ic c o m p o u n d s . T h e r e a c tio n s o f a lu m in u m c h lo r id e w it h h u n d r e d s o f c o m p o u n d s a re d is c u sse d in d e ta il; a n d a fe a tu r e o f th e b ook is th e p r e s e n ta tio n o f th e e x a ct c h a n g e s w h ic h o c c u r in s t r u c tu r e . A r e s u m e o th e w ork o f F ried el a n d C ra fts, w h o d id t h e p io n e e r w ork i n th is fie ld , is in c lu d e d . I h is is in d e e d a m o n u m e n t a c o m p ila tio n w h ic h w ill b e in v a lu a b le to r e sea rch w ork ers i n t h e field s o f p e tr o le u m , p la s tic s , ru b b er, s y n t h e t ic c o a tin g s , flo ta tio n a g e n ts , d y e s , fa t s a n d w a x es, c le a n s in g a n d d r y -c le a n in g a g e n ts , p e r fu m e s a n d t e x t ile s . 972 Pages A m e ric a n C h e m ic a l S o c ie ty M o n o g ra p h No. 87 P ric e $16.50

R E IN H O L D P U B L IS H IN G C O R P O R A T IO N n „V y . * w ! n . y :'

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August, 1946 A N A L Y T I C A L E D I T I O N

TH E GAS ANALYST

W ithin a single 96-page book, Burrell presents complete infor

mation on modern gas analysis apparatus and the latest analyt

ical methods used in the indus

trial field.

1 he catalog section of this book describes and illustrates the comprehensive line of B urrell laboratory and portable models in both the B uild-U p and Cabi

net types w ith equipment for the new ^ catalytic method of com

bustion.

The manual is really a text

book describing the technique of gas analysis in sufficient detail to provide the inexperienced an

alyst with a working knowledge o f the subject and enabling him to carry through from the as

sembly of the apparatus to the calculation of the components in any particular analysis.

Because of the prevailing paper shortage, the size of the edition necessarily has been limited. I f you have not already received

your copy, we recommend that

you write prom ptly for B urrell

Gas Analysis Catalog 80. B urrell

Technical Supply Co., 1936-42

Fifth Ave., Pittsburgh 19, Pa.

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T H E M erck line o f R eagents and C. P . Chemi

cals, as well as i those chemicals suitable for industrial research, educational, and routine plant laboratory uses, is comprehensive. C .P . and R eagent mineral acids and Amm onia W ater are o f highest purity, and are indicated wherever those acids are used.

The use o f R eagent grade chemicals in plant operations is constantly increasing. If, in your ex

perimental work, you find the need o f a chemical of special purity, or one made to m eet your individual specifications, our technical and manufacturing facil

ities are well adapted to- the production of such custom -m ade chemicals.

MERCK & CO., Inc., RAHWAY, N. J.

P lease send m e th e following ch a rts:

.R evised Q u alitativ e A nalysis C h a rt Periodic C h a rt o f th e E lem en ts Sensitivity C h a rt

N a m e . * *.*...

C o m p a n y ...

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C ity ... S ta te ...

IN D . E N G . 8 - «

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No. 17030 - ST Blue Line E X A X Retested Burette, with 1JT straight glass stopcock

Capacity ml.

Subdivision ml.

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Quantify

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1 0 .0 5 2 1 2 $ 1 .9 3 $ 2 0 . 7 9

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

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

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

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^OCIATES

in», frs-w ,» ú

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NEW COMPOUNDS AND NEW USES

P R O D U C T S E X H I B I T E D

Organo-Mercurials • Quaternary Ammonium Compounds • Fluorescent Powder • Pyridine Derivatives •

Lecithin • Colloidal Iron Salts

W. A . CLEARY CORPORATION

NEW B R U N S W I C K , N. J. and CHI CAGO, 111- are shown at booth 116

National Chemical Exposition by W. A. Cleary Corp. • American Research Associates

Fluorescent Chemical Corp.

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V E R T IC A L T Y P E M E C H A N IC A L C O N V E C T IO N O V E N

H e a t t r a n s f e r b y m e c h a n ic a l c o n v e c tio n , w it h a p o w e r f u l tu rb o - b lo w e r fo rc in g a i r into m o tio n th ro u g h th e w o rk in g c h a m b e r, to s e rv e a s th e v e h ic le o f h e a t t r a n s f e r , o ffe rs th e p e a k o f o v e n e ffic ie n c y f o r h u n d re d s o f la b o r a t o r y a p p lic a t io n s . In te r io rs a r e 18*8 s ta in le s s s te e l, e x t e r io r s o f c it h e r s ta in le s s ste e l o r ru s t- r e s is tin g iro n . T h re e s ta n d a rd s iz e s —tw o te m p e ra tu re ra n g e s .

S T E A M H E A T E D C O N S T A N T T E M P E R A T U R E C A B IN E T

T e ste d a n d R a te d E x p lo s io n P ro o f fo r T e m p e ra tu re to 3 0 0 ° F b y

U n d e rw rite rs L a b o ra to ry

F o r use in h a z a rd o u s lo c a tio n s , a s d e s ig n a te d b y U n d e rw rite rs ' C la s s 1, G ro u p C a n d G ro u p D w h ic h in c lu d e s a tm o s p h e re s c o n ta in in g e th y l e th e r v a p o r , g a s o lin e , p e tro le u m , n a p h th a , a lc o h o ls , a c e to n e , la c q u e r, s o lv e n t v a p o r s a n d n a tu ra l g a s e s . E x p lo s io n - p ro o f fe a tu r e s in c lu d e a u to m a tic te m p e ra tu re co n tro l b y m e a n s o f a p n e u m a tic th e rm o s ta t—use o f s a tu ra t e d s te a m (n o t s u p e rh e a te d ) a t a n y p re s s u re b e tw e e n 0 a n d 100 lb s .

S T A N D A R D M E C H A N I C A L C O N V E C T IO N O V E N S

U tiliz in g th e sam e p r in c ip le o f m e c h a n ic a l c o n v e c tio n th ese " P r e c is io n " - F r e a s ove ns p ro d u ce a ra p id m o v e m e n t o f a la rg e v o lu m e o f h e a te d a i r , w h ich co n ve ys h e a t d ir e c t ly to th e lo a d u n d e r ab so lu tely^ c o n tro lle d te m p e ra tu re c o n d itio n s . L a rg e w o rk in g c h a m b e r, a d ju s t a b le sh e lv e s a n d c o n tro lle d a i r v e lo c ity a cro s s w o rk in g c h a m b e r m eans e xtre m e f l e x ib ilit y fo r m an y v a r ie d te s t s . T h re e s ta n d a rd s iz e s — tw o te m p e ra tu re ra n g e s.

L O W T E M P E R A T U R E C O N T R O L C A B IN E T A u to m a tic te m p e ra tu re co n tro l a t a n y p o in t fro m 6 ° to 4 0 ° C . In a d d itio n to its w i d e s p r e a d a n d g e n e ra l a p p lic a b ilit y a s a lo w te m p e ra tu re c a b in e t f o r use in a p h y s ic a l, c h e m ic a l o r b io lo g ic a l la b o r a t o r y , .this c a b i

net w i l l be fo u n d a d a p t a b le to m a n y s p e c ific uses such a s b io -c h e m ic a l o x y g e n d e m a n d ( B .O .D .) d e te rm in a tio n s in th e tre a tm e n t c o n tro l o f s e w a g e a n d in d u s t r ia l w a s t e f lo w , a c c o rd in g to th e m eth o d a d o p te d b y th e A m e ric a n P u b lic H e a lth A s s o c ia tio n , s p e c ify in g in c u b a tio n a t 2 0 ° C . O th e r b io lo g ic a l uses in c lu d e th e p re s e rv a tio n o f v a c c in e s , such a s in s u lin a n d liv e r e x tr a c t s (a t 1 5 ° C . ) ; s e ro lo g ic a l a n d co m p le m e n t fix a t io n te sts a t lo w te m p e ra tu r e s , a n d e n z y m a t ic d ig e s tio n p ro c e ss e s .

G R A V I T Y C O N V E C T IO N H O T A IR S T E R IL IZ E R

S p e c ia lly b u ilt f o r flu s h -m o u n tin g w a l l in s u la tio n in k e e p in g w it h th e la y o u t o f m o d ern h o s p ita l e q u ip m e n t, th is u n it h a s a n in s id e w o rk in g c h a m b e r 30 x 24 x 3 6 " . C a b in e t is e le c t r ic a lly h e a te d , t h e rm o s ta t ic a lly c o n tro lle d , m a x im u m te m p e ra tu re 3 5 0 ° F

S T A N D A R D G R A V I T Y C O N V E C T IO N O V E N S

" P r e c is io n " —F re a s g r a v it y co n v e c tio n o v e n s o ffe r a d e g re e o f p e rfo rm a n c e a n d d e p e n d a b il i t y u n e q u a le d b y a n y c o m p a ra b le e q u ip m e n t. S in c e g r a v it y c o n ve c tio n d e p e n d s up on n a t u r a l a i r c ir c u la t io n in d u ce d b y th e te m p e ra tu re d iffe r e n t ia l b e tw e e n h e a t sp u rce a n d e x h a u s t p o rt, g r a v t iy co n v e c tio n o v e n s a r e re co m m e n d e d w h e r e th e fa c to rs o f h e a t t r a n s f e r s p e e d , o r lim it o f c a b in e t lo a d a b ilit y , a re not th e fo re m o s t c o n s id e ra t io n . In te r io r w a l l s , s h e lf b ra c k e ts a n d f a s te n in g s a re b u ilt o f 18-8 s ta in le s s s te e l. E x t e r io r w a l l s o f s ta in le s s s te e l o r ru s t- re s is tin g iro n . F o u r s ta n a d rd m o d e ls —tw o te m p e ra tu re ra n g e s .

W r i t e f o r c a t a l o g 3 2 5 - J c o n t a in i n g c o m p le t e in f o r m a t io n o n a l l s t a n d a r d a n d s p e c i a l m o d e ls o f " P r e c i s i o n " —F r e a s C o n s t a n t T e m p e r a t u r e E q u ip m e n t .

M ETA L,

w a h! L a l \ d°u b l e- w a l lED/ W E L D E D /

s t r e a m l i n e d

G L A S S O B S E R V A T IO N D O O R IN S U L A T E D D O O R ,

R E F R IG E R A T O R H A R D W A R E

S T R U C T U R A L B R A C IN G , A S B E S T O S S T R IP P IN G

G L A S S W O O L B L A N K E T IN S U L A T IO N

A D JU S T A B L E V E N T IL A T IO N

C O N T R O L •

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H E V I D U T Y E L E C T R I C

H E A T T R E A T I N G F U R N A C E S e l e c t r i c e x c l u s i v e l y

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

18, No. 8 I N D U S T R- I AL A N D

Duty Electric M uffle Furnaces are used by

The Babcock & W ilcox Tube Company

in their continuous, extensive research an d testing in connection w ith the m etallurgical aspects of their q u ality tubular products. A m ong other investigations these furnaces are used for a g in g tests on high a llo y steels. These tests have continued for a s long a s 1 3 ,0 0 0 hours in determ ining w h a t p hase changes occur in certain a llo y m aterials on extend

ed h e a tin g Hevi Duty M uffle Furnaces h ave accuracy, d ep en d ab ility an d econom y of operation that recommend them for intensive a n a ly tica l research. Bulletins H D -537 an d H D -637 h ave com plete d etails — send for them — today.

t A U . 5 5 ° n - 9 6

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SP tfK A N Í©

PORTLAND

(CAMBRIDGE

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/ D E T R O I Tß f \ PHILADELPHIA

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KANSAS CITY BERKELEY

LOS ANGELES

JACKSONVILLE

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CHEMICAL WORKS

l o c€ /i& m s ic c ts l f y / â e ï ô -

7 2 G old St., N ew Y o r k 8, N. Y .

LO S A N G E L E S . M O N TR EA L

MALLINCKRODT gg

M a llin ck ro d t St., St. Louis 7 , Mo

C H IC A G O • P H IL A D E L P H IA

AN ALYTICAL REAGENTS

1 . M A C A L A S T E R B IC K N E L L C O M P A N Y 243 B ro a d w a y

C a m b rid g e , M a s s a c h u s e tts

2 . C A M B O S C O S C I E N T I F I C C O M P A N Y 37 A n tw e r p S tre e t

B r ig h to n S ta tio n 35 B o s to n , M a s s a c h u s e tts

3 . M A C A L A S T E R B IC K N E L L C O M P A N Y 412 T e m p le S tre e t

N ew I la v c n 11, C o n n e c tic u t 4 . E . M A C H L E T T A N D SO N

220 E a s t 23rd S tre e t N ew Y o rk 10, N e w Y o rk

5 . S C IE N T I F IC G L A S S A P P A R A T U S C O M P A N Y 49 A c k e r m a n S tre e t

B lo o m fie ld , N e w J e rs e y (6. H A R S H A W S C IE N T I F IC

D iv is io n o f t h e H a r s h a w C h e m ic a l C o m p a n y Jn c k ß o n a n d S w a n s o n S tre e ts

P h i la d e l p h ia 4 8 , P e n n s y lv a n ia W IL L IA M S , B R O W N & E A R L E IN C . 918 C h e s tn u t S tre e t

P h i la d e l p h ia 7 , P e n n s y lv a n ia 7 . S U R G IC A L S U P P L Y C O M P A N Y

36 W est D u v a l S tre e t J a c k s o n v ille , F l o r i d a

8 . A T L A N T IC C H E M IC A L S , IN C .

601 S o u th H u g h e y S tr e e t ^ 12 S o . D a v is S tre e t O r la n d o , F l o r i d a J a c k s o n v ille , F lo rid a 9. B IS C A Y N E C H E M IC A L L A B O R A T O R IE S

2207 N .E . S e c o n d A v e n u e M ia m i 3 7 , F lo rid a

10. B U R R E L L T E C H N IC A L S U P P L Y fcO M P A N Y 1936-1J42 F i f t h A v e n u e

P i tt s b u r g h 19, P e n n s y lv a n ia 11. B . P R E I S E R C O M P A N Y I N C .

•-■416 W e st W a s h in g to n S tre e t C h a r le s to n , W e st V irg in ia

1 2 . S U R G IC A L S E L L IN G C O M P A N Y 139 F o r re s t A v e n u e , N .E . A t l a n t a 1 , G e o rg ia 13. H A R S H A W S C IE N T I F IC

D iv is io n o f t h e H a r s h a w C h e m ic a l C o m p a n y 1945 E a s t 9 7 th S tre e t

C le v e la n d , O h io

14. E B E R B A C H & SO N C O M P A N Y 200 E a s t L ib e rty S tre e t A n n A r b o r , M ic h ig a n 1 5 . H A R S H A W S C IE N T I F IC

D iv is io n o f t h e H a r s h a w C h e m ic a l C o m p a n y 9240 H u b b e ll A v e n u e

D e t r o i t , M ic h ig a n

F R A N K W . K E R R C O M P A N Y 422 C o n g re ss S tre e t

D e t r o i t , M ic h ig a n

1 6 . T H E O R R , B R O W N 8- P R I C E C O M P A N Y S p rin g & F r o n t S tre e ts

C o lu m b u s , O h io 17. H A R S H A W S C IE N T I F IC

D iv is io n o f th e H a r s h a w C h e m ic a l C o m p a n y 224 M a in S tre e t

C in c in n a ti 2 , O h io

1 8 . C H IC A G O A P P A R A T U S C O M P A N Y 1735 N . A s h la n d A v e n u e

C h ic a g o 2 2 , I llin o is

W . M . W E L C H M A N U F A C T U R IN G C O M P A N Y

• 1515 S ed g w ick S tre e t C h ic a g o , Illin o is 19 . A . S . A L O E C O M P A N Y

18 1 9 -1 8 2 3 O liv e S t r e e t S t. L o u is , M isso u ri

20 . G E O R G E T . W A L K E R C O M P A N Y 324 F i f t h A v e n u e S o u th

M in n e a p o lis , M in n e s o ta

2 1 . A . J . G R IN E R C O M P A N Y 1827 M c G e e A v e n u e K a n s a s C ity 8, M is s o u ri 2 2 . C H E M IC A L P R O D U C T S I N C .

501 W e st F i r s t S tre e t T u l s a 3 , O k la h o m a 2 3 . G R E E N E B R O T H E R S IN C .

1812 G riffin S tre e t D a lla s , T e x a s

2 4 . S O U T H W E S T S C IE N T I F IC C O R P . 122 S o u th S t. F r a n c is S tre e t W ic h ita 12, K a n s a s

2 5 . W A S A T C H C H E M IC A L C O M P A N Y 2225 S o u th F i f t h E a s t

S a lt L a k e C ity 5 , U ta h

2 6 . T H E C. M . F A S S E T T C O M P A N Y W e st 19-21-23 M a in A v e n u e S p o k a n e , W a s h in g to n 2 7 . S H A W S U R G IC A L C O M P A N Y

Y a m h ill & N in th A v e n u e P o r tl a n d , O re g o n

28. U N I V E R S IT Y A P P A R A T U S C O M P A N Y 2229 M c G e e A v e n u e

B e rk e le y 3 , C a lif o r n ia 2 9 . C A L K IN S D I V IS I O N

L o s A n g e le s C h e m ic a l C o m p a n y 934 S o u th M a in S tre e t L o s A n g e le s 15, C a lif o r n ia

T H E W H O L E S A L E S U P P L Y C O M PA N Y 1047 N o r th W ilc o x A v e n u e

Los A n g e le s 3 8 , C a lif o r n ia

A LW A Y S SPECIFY M A LLIN CKRO D T REAGENTS

IN O R IG IN A L P A C K A G ES

Yo u are co rd ia lly invited to visit M a llin ck ro d t’s Booth N o . 18 in the Chicago Coliseum at the 1 9 4 6 N ational Chem ical Exposition/ Septem ber 1 0 -1 4 .

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18 I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y Xol. 18, No.

A . H . T . C O . M O D E L H-1

An improved execution of a tim e-tested, simplified design, for use in quantitative analysis

A V A ILA BLE FO R IM M ED IA TE SHIPM ENT FR O M O U R STO CK

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

R E T A I L — W H O L E S A L E — E X P O R T

L A B O R A T O R Y A P P A R A TU S AND R E A G E N T S

W E S T W A S H IN G T O N S Q U A R E , P H I L A D E L P H I A 5, P A ., U .S .A .

Cable Address “ Balance” Philadelphia

ANALYTICAL BALANCE, A. H . T. Co. M odel H-1. An im proved execution of a tim e-tested, simplified design, w ithout draw er in base, intended for use in industrial or educational laboratories for q u an titativ e analysis. Especial atten tio n has been given to the design of th e beam, beam support, .stirrups and stirrup rests, so th a t erecting and cleaning can be accomplished quickly and with minimum

danger of damage to the delicate p a rts such as agate knife edges, etc.

Sensitivity— 0.1 m illigram w ith full load. A djusted so th a t th e change of w eight of 1 m g on th e p a n deflects th e ■ p o in ter on th e scale a t least 2 A divisions w ith full load.

Capacity— 200 gram s in each pan.

C ase—Of m ahogany, w ith counterpoised fro n t door, circular level a n d leveling screws, b u t w ith o u t draw er in base.

O ver-all dim ensions, lGJ^ inches wide x 1G inches high x 9 A inches deep.

C entral P illa r — Of D uralum in, oxidized black, % -inch diam eter.

B eam —Of h ardened alum inum , 6 inches long, w ith oxidized black finish. G rad u ated in w hite on b o th sides of cen tral knife edge from 0 to 5 m g in 1/10 m g divisions, using a 5 m g rider.

R id er C arrier— M o u n ted on a slo tted ro d of D uralum in;

will pick u p an d accu rately a d ju s t rid er w ith o u t striking th e beam .

K nife E d g es and P la n e s— Of a g a te th ro u g h o u t.

R elease and Arrest—T h e beam an d hangers are released by a single action device m aking th e c o n ta c t of th e central knife edge sim ultaneous w ith th e c o n tac t .of th e end knife edges an d bearings. T h e construction of th e arrestin g device is sim ple an d rugged, engaging an d su p p o rtin g th e b eam an d hangers free of an y c o n ta c t w ith th e knife edges an d bearings, th u s p rev en tin g a n y possible dam age while loading an d unloading th e pan.

Pointer Scale—O f ivory, recessed so t h a t th e end of th e p o in ter m oves in th e offset in th e sam e v ertical plane as th e division on th e scale, th u s avoiding errors of parallax.

Pan Arrest— Of th e self-locking, a d ju sta b le p u sh -b u tto n type.

P ans—Of polished D uralum in, “¿ A inches diam eter.

Arches— Of polished D uralum in, h eig h t 7 A inches, spread 4 inches.

R id e rs—E a c h balance is furnished w ith tw o 5-mg alum inum riders.

1812. B alance, A nalytical, A .H .T . Co. M odel H -1, as above described, w ith tw o 5-mg alum inum riders b u t w ith o u t

w eights... $82.50

Code W ord... Aoant 5 % discount in lots o f 6

12 or more

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INDUSTRIAL and ENGINEERING CHEMISTRY

L I S H E D BY

A M E R I C A N C H E M I C A L S O C I E T Y ' W A L T E R J. M U R P H Y ,

E D I T O R

Applications of Infrared Spectroscopy to DDT

J. R. D O W N I N G , W . V . F R E E D , I . F. W A L K E R , a n d G . D. P A T T E R S O N Chemical Department, E. I. du Pont de Nemours & C o ., Inc., Wilmington, D el.

Infrared spectroscopy provides a valuable tool for the chemical characterization of technical D D T, including detection of the several isomers and impurities and quantitative estimation of D D T content.

This technique' has been applied in establishing the purity of com

mercial samples for use in formulation studies and in determining low concentrations of D D T in residues and dispersions.

U

T IL IZ A T IO N of dichlorodiphenyltrichloroethane (D D T ) b y th e arm ed forces a n d increasing in te re st in p o te n tia l postw ar a g ric u ltu ra l a n d dom estic applications h ave focused a tte n tio n on new m eth o d s for th e identification a n d q u a n tita tiv e estim ation of D D T . V arious a n a ly tic a l m ethods h av e been de

vised for th e q u a n tita tiv e d eterm in atio n of p ,p ’-D D T tog eth er w ith its isom ers. W in ter (10), H all et al. (5), a n d F a h e y (3) h av e em ployed m eth o d s of analysis depending upon th e d eterm in atio n of halogens in organic com pounds. N eal et al. (7) a n d G u n th er (4) h ave described m eth o d s for d eterm ining D D T b ased up o n de- hydrohalogenation w ith alcoholic alk ali a n d d eterm in atio n of th e resulting IIC1. C olorim etric m ethods h ave been rep o rted by Schechter et al. (8, 9) a n d B ailes (1). C ristol, H ayes, an d H aller (2) h a v e described a m eth o d fo r th e d e term in atio n of p ,p '-D D T in technical D D T by recry stallizatio n from sa tu ra te d solutions of pu re p ,p '-D D T in aqueous ethanol.

Such m ethods are v ery useful b u t th ere is still a recognized need for a tech n iq u e w hich will id en tify th e several isom ers of D D T a n d avoid com plications arising w hen D D T is associated w ith o th e r chlorine-containing com pounds.

T he term D D T is em ployed here in accordance w ith term inol

ogy in com m on usage in c u rre n t lite ra tu re p ublications: “ T he sym bol ‘D D T ’ is a c o n tractio n for dichloro-diphenyl-trichloro- ethanc, th e generic nam e of th e active insecticidal principle.

T heoretically th e re are forty-five possible dichlorodiphenyttri- chloroethanes. H ow ever, th e te rm ‘D D T ’ is confined to th e p ro d uct ob tain ed on condensation of chloral (or its alcoholate o r h y drate) w ith chlorobenzene in th e presence of sulfuric ac id ” (6).

W hen referring to specific isom ers of D D T , fo r exam ple, p ,p '- D D T is u s e d to d esignate l,l,l- tric h lo r o -2,2-bis(p-chlorophenyI)- ethane an d o ,p '-D D T for l,l,l-trich lo ro -2 -o -ch lo ro p h en y l-2 -p - chlorophenylethane.

In th is lab o rato ry , ab so rp tio n spectroscopy h as been success- fully'applied to th e chem ical ch aracterizatio n of D D T in connec

tion w ith th e developm ent of special form ulations for use b y th e arm ed forces. I t h a s been show n t h a t in frared spectroscopy provides a m eans of determ ining b o th th e p u rity of D D T an d the presence of relativ e p ro p o rtio n s of th e isom ers a n d im purities which m ay occur along w ith p ,p '-D D T .

I t is well know n t h a t certain chem ical stru c tu ra l u n its possess characteristic, isolated, in frared ab so rp tio n frequencies. By study of reference sam ples of D D T a n d selected isomers, absorp

tion b an d s m a y be assigned to th e D D T molecule an d to th e iso

mers a n d b y -p ro d u cts associated w ith com m ercial D D T . C riti

cal exam ination of th e ab so rp tio n sp ectru m m akes it possible to

. determ ine q u alitativ ely th e p u rity of a given sam ple of D D T and also th e n a tu re of th e im purities. A q u a n tita tiv e an aly tical m eth o d for D D T p u rity a n d co n cen tratio n m ay be devised on th is basis. B o th procedures h av e been used in th e c u rre n t re

search for ch aracterizing com m ercial D D T ’s a n d for estim atin g D D T in sp ra y com positions.

A P P A R A T U S

T h e in frared sp ectro g rap h used in th is w ork w as b u ilt in 1040 in th e physics shops of th e U n iv ersity of M ichigan u n d e r th e supervision of H . M . R an d all. I t is a rock s a lt prism spectrom ete r of conventional optical design, using a 15-cm. rock s a lt prism a n d an off-axis parabolic m irro r of 1-m eter focal length. A record of p er cent transm ission versus w ave len g th is recorded directly by m eans of a periscopic b eam -sp littin g device a n d a re

cording potentiom eter.

T h e sp ectrograph is calib rated in term s of w ave lengths by ru n n in g th e sp ectra of s ta n d a rd substances such as am m onia (Figure 1), carb o n dioxide, a n d w a te r v apor. T h e in stru m en tal q u a lity p erm its a precision in m easuring w ave len g th s of absorp

tio n ban d s of —0.01 m icron o r b e tte r, a lth o u g h th e practical accuracy in assigning w ave lengths in ro u tin e w ork is usually n o t g re a te r th a n ± 0 .1 m icron. All w ave len g th s except those in F igure 1 a re therefore expressed in th e n earest 0.1 m icron.

I n stu d y in g D D T , carbon disulfide w as used as th e solvent.

R ock s a lt cells, 5 or 20 m ils th ick , w ere used to hold th e D D T solutions.

T h e volum e of D D T solution prep ared w as usually a b o u t 5.0 ml., b u t less th a n 0.2 m l. is required to fill th e ab so rp tio n cell.

T h e in frared ab sorption spectrum can be o b tain ed from as little as 1 mg. of D D T if th e volum e of th e solution is restricted to 0.2 ml.

A bout 45 m in u tes are required to record th e com plete spectrum over th e range 1 to 15 m icrons. I f only th e range 7 to 12 m icrons is exam ined, a record can be m ade in a b o u t 10 m inutes.

S O U R C E O F R E F E R E N C E C O M P O U N D S

Pu r e p ,p '-D D T (m .p. 108.6-109.5° C. corrected). U. S.

P ublic H e a lth Service; a sam ple purified by M erck & Co. for the In s e c t C ontrol C om m ittee of th e Office of Scientific R esearch.and D evelopm ent.

0 ,p '-D D T (m.p. 73 -7 4 ° C.). G rasselli C hem icals D e p a rt

m en t, E . I. du P o n t de N em ours & C om pany, C leveland, Ohio.

m ,p '-D D T (liquid a t room te m p e ra tu re ). B u reau of E n tom ology a n d P la n t Q u aran tin e, U. S. D e p a rtm e n t of A gricul

tu re , B eltsville, M d .; a sam ple furnished b y M . S. N ew m an, Ohio S ta te U niversity.

1 ,1 - D ic h lo r o - 2 ,2 - b is ( p - c h lo r o p h e n y l) e th y le n e (m .p. 88- 89° C. corrected). P rep ared in th is lab o rato ry .

Bis(p-CHLOROPHENYL)sur,FONE (m .p. 148-149° C. corrected).

P rep ared in th is lab o rato ry .

2 ,2 ,2 -Tr ich lo r o- 1 - (o-ch loroph en yl)f.t h y l- /j -chloroben-

zen esu lfo n a t e (m .p. 105-106° C.). B u reau of E ntom ology a n d P la n t Q u aran tin e, U. S. D e p a rtm e n t of A griculture, B elts

ville, M d .; a sam ple from P . D . B a rtle tt, H a rv a rd U niversity.

1, 1-Dichloro-2,2-b is(p-chlorophenyl) e t h a n e (p ,p '-D D D ) (m .p. 108-109.5° C .). B u reau of E ntom ology a n d P la n t Q uar

a n tin e, U. S. D e p a rtm e n t of A griculture, Beltsville, M d .; a sam ple furnished b y H . S. M osher, P ennsylvania S ta te College.

T hese reference com pounds were stu d ied w ith o u t p u rifying to constancy of infrared spectrum .

461