ir
Published 'Monthly by The American Chemical Society
E d ito r: H . E . H o w e
A s s is ta n t to E d ito r: N . A . P a r k i n s o n
A ssociate E d ito r: R . T . S t o k e s ( On e Ma d i s o n Av b., Ne w Yo r k Ci t y)
A d iiso ry Board: H . E . Ba r n a r d J . W . Be c k m a n A. D . Li t t l e A. V. H . Mo r y Ch a s. L . Re e s i î Ge o. D. Ro s e n g a r t e n T . B . Wa g n e r
Ed i t o r i a l Of f i c e:
810 E ig h te e n th S t., N . W.
W a s h in g to n , D . C.
Té l é p h o n é: M a in 848 C ab le A d d re ss: J I E C H E M (W ashington)
Ad v e r t i s i n g De p a r t m e n t: 170 M e tro p o lita n T ow er
N ew Y o rk C ity Te l e p h o n e: G ra m e rc y 2145
Volume 14 JU LY 1, 1922 No. 7
Co n t e n t s Ed i t o r i a i-s... 5SG-5S8 D e to n atio n C h a ra c te ris tic s o f B le n d s of A ro m atic a n d P araffin H y d ro
carb o n s. Th o m a s Mi d g l e y, Jr., a n d T . A . Bo y d...... 589 N ew Q u alitativ e T e s t fo r U ra n iu m . Ha r o l d D . Bu e l l... 593 C arb u re to r A d ju s tm e n t b y G a s A n aly sis. A . C . Fi e l d n e r a n d G . W .
Jo n e s..
P rev e n tio n of C o rro sio n of M e ta ls by W a te r in a C lo sed S y ste m . Pe r r y We s t... ...
Wood a s a C h em ica l E n g in e e rin g M a te ria l. Cl a r k S . Ro b i n s o n...
A pparatus of T r a n s p a re n t B a k e lite fo r M e a s u rin g H y d ro flu o ric Acid.
L . J . C U R T M A N ...
S y n th esis of U rea fro m A m m o n ia a n d C arb o n D io x id e. No r m a n W . Kr a s ea n d V . L . Ga d d y... ...
A utom atic C arb o n D io x id e In d ic a to r fo r F lu e G as.
L IN ...
594
001
607
010
611 Studies in W ood D e ca y . I l l — T h e T oxicity of W e s te rn Y ellow P in e
C ru d e O il to L en zites S a ep ia ria Fries. He n r y Sc h m i t z... 617 D rying O ils fro m P e tro le u m a n d O th e r P ro d u c ts , P ro d u c e d b y C hlori
n atio n a n d D e c h lo rin a tio n . He n r y A . Ga r d n e r a n d E . Bi e l o u s s 619 Studies in C h ro m e T a n n in g . E q u ilib ria b e tw e e n T e tra c h ro m e Col
lagen a n d C h ro m e L iq u o rs. T h e F o rm a tio n of O c tac h ro m e Colla
gen. Ar t h u r W . Th o m a sa n d Ma r c a r e t W . Ke l l y... 621 P ressu re B o ttle fo r L a b o ra to ry U se . Ar t h u r D . Hi r s h f e l d i j r a n d
M ; C . Ha r t...'...
E stim atio n of S u lfa te in N e o a rsp h e n a m in e . El i a s El v o v e...
T h e S u rface T e n s io n of P e tro le u m . C . K . Fr a n c i sa n d H . T . Be n-
R . B . Ma cMu l- 623 624
626
62S M an u fac tu re of P h o sp h o ric Acid in th e E lec tric F u rn a c e by th e C on
d e n sa tio n a n d E le c tric P re c ip ita tio n M e th o d . Th e o d o r e Sw a n n. . 630 K ellogg’s S a m p lin g H o rn . Ja m e s W . Ke l l o g g ... 631 D e te rm in a tio n of F re e C h lo rin e a n d H y p o c h lo ro u s A cid in C oncen
tra te d S a lt S o lu tio n s. M . C . Ta y l o r a n d C . A . Ga m m a i...
B en zen e a s a M o to r F u e l. J . J . La w t o n...
R ecovery of P la tin u m fro m U se d C o n ta ct M a s s a t th e O ld H ick o ry P o w d e r P la n t. A . L . Ki b l e r...
632 635
636
F ir s t R ep o rt of the C om m ittee on C o n tact C atalysis. Wi l d e r D . Ba n c r o f t...
E arly R eferen ces P e rta in in g to C hem ical W arfa re . C. A. Br o w n e. ..
S tu d y of C hem ical E n g in eerin g by th e U n it-O p e ra tio n M e th o d . W.
K . Le w i sa n d R . T . Ha s i.a m...
No t e s a n d Co r r e s p o n d e n c e:
P e tro le u m H y d ro c a rb o n s; T h e P la n t M a n a g e r a n d th e C h em ist;
T h e Electrolytic P ro d u ctio n of Lead A rse n a te ; C a n a d ia n L e tte r Sc i e n t i f i c So c i e t i e s:
P ittsb u rg h M eetin g ; C alen d ar of M ee tin g s; T e c h n ic al P h o to graphic a n d M icroscopic S o ciety ; T h e N ew H a v en M ee tin g
— Spring 1 9 2 3 ; Local Section O fficers; C o rre sp o n d e n ts in Local S ectio n s; A U n iq u e M ee tin g ; M e e tin g of th e Iow a a n d A m es S ectio n s; R e p o rt on S ta n d a rd iz a tio n of S izes a n d S h ap es of A p p aratu s— II ; C h em ical E n g in ee rin g E d u cation C onference; A m erican O il C h em ists’ S o c ie ty ...
Mi s c e l l a n e o u s:
G asoline S ta tis tic s ...
Civil Service E x a m in a tio n ...
R eview of Scientific I n s tru m e n ts ...
In te rn a tio n a l C ongress on Liquid F u e ls ...
A R e q u e s t for J o u rn a ls ... ...
Lo n d o n Le t t e r... ...
Wa s h i n g t o n No t e s... ...
Pa r i s Le t t e r... ...
Pe r s o n a l s...
In d u s t r i a l s...
Bo o k Re v i e w s...
Co m m e r c e Re p o r t s...
Cu r r e n t Pu b l i c a t i o n s...
Ma r k e t Re p o r t. . . ...
642 646
647
650
652
600 616 631 631 635 660 661 662 663 663 664 667
668
670
S u b s c rip tio n to n o n -m e m b e rs, $7.50; sin g le c o p y , 75 c en ts, to m em b ers, 60 c en ts. F o reig n postage, $1.00, C a n a d a , C u b a a n d M ex ico ex ce p te d . S u b s c rip tio n s a n d c la im s for lo st copies sh o u ld be re fe rre d to C h arle s L . P arso n s, S e c re ta ry , 1709 G S tr e e t, N . W ., W a s h in g to n , D . C.
M em b e r of A u d it B u re au oL C ircu latio n s
E D I T O R I A L S
Now—All Together !
0 0 M U C H h as been accom plished in th e passage b y th e
^ Senate of th e p ara g ra p h s in th e tariff bill relatin g to coal-tar interm ediates and dyes th a t we m u st m ak e a final effort now for th e em bargo. W e are ra p id ly passing o u t of th e period w hen people generally w ere clam oring for A m erican industries an d w ere willing to go to w h a t th e y con
sidered great lengths o u t of p a trio tic m otives. T o -d a y th e principal o bject seems to be to b u y as cheaply— anyw here—
as possible and to sell a t th e to p price.
B u t ac tu a l conditions hav e changed little . Im p o rted m aterials are offered on a low price basis m ore often th a n upon high quality . In his first new spaper interview a recently arrived am bassador to o k occasion to condem n o ur dyes and praise those of his country.
T h a t th e S enate saw fit to pass th e p ara g ra p h s m entioned indicates a g rea t gain n o tw ith stan d in g m a n y difficulties.
T he w ay th e d u ty on scientific a p p a ra tu s was reduced from 55 per cen t to 35 p e r cen t in a b o u t tw o m in u tes w ith some te n senators on th e floor indicates th e m a n y slips possible.
I f you hav e n o t expressed y o u r view s to y o u r senators and representatives, do so now. I f you hav e urged favorable consideration of th e w hole chem ical program , send in a rem inder.
M uch has been gained. T h e d a y can be won if we all work together, and now!
Textile Research In stitu te
T N T H E hearings before th e S enate com m ittee investi- gating dyes, th e sta te m e n t w as m ade th a t th e re re
m ain to be invested in education and research several hu n dred thousand dollars representing th e profits of th e Textile .Alliance, in accordance w ith th e original u n d ersta n d in g w ith the S tate D ep a rtm en t.
We urge th a t th is fund be devoted to th e establishm ent of an A m erican T extile R esearch In stitu te . N o tw ith
standing th e w ork of governm ent bureaus, p riv ate corpora
tions, an d textile schools, th e re are concerted efforts abroad w hich surpass an y th in g we have to offer. As an industry, textile m anufacturers have n o t y e t been convinced th a t th e y can conduct research as an association enterprise.
W e believe th a t unless th e p rese n t o p p o rtu n ity is utilized it m ay be m any years before ad e q u ate w ork will be su p ported here.
A simple effective plan can be devised. C otton, wool, linen, and silk should be represented in th e in stitu te . T here are strong trad e associations representing these fibers. T here is a splendid association of finishers, an d still o th e r groups of spinners, dyers, d ry cleaners, laundrym en, an d o ther crafts directly concerned w ith textiles. F rom these groups a strong advisory com m ittee can be form ed and b y utilizing th e income from th e fund to be available a deal of im p o rta n t work can be carried on in existing laboratories thro u g h o u t th e country. T h e initial staff of th e in stitu te could consist of a director w ith p roper assistants, an d if desirable an early a c tiv ity could be the establishm ent of inform ational service and a statistical bureau and a p roper m edium for broad
casting new inform ation.
To divide th e cap ital sum am ong those now in terested in textile research seems to us unwise, for provision should be m ade for stu d y of new problem s as th e y m ay arise in w h at
ever laboratory m ay be b est fitted for th e investigation.
B y keeping th e p rese n t sum as a fu n d o th e r m oney is sure to be attra c te d , an d th e re would be available annually a sum which u n d er wise adm inistration w ould eventually b rin g to th e laboratories far g reater su pport.
P lans should be perfected, and it is ou r hope th a t th e com
m ittee appointed b y th e Textile Alliance to consider and recom m end m ethods for th e em ploym ent of th e m oney in h an d m a y decide upon some such program as we have here suggested.
T he Chemical Exposition
X J 0 O N E can d o u b t th a t th e chemical exposition has played a useful p a r t in prom oting chem ical industry in our country. W e are approaching th e E ig h th N ational E xposition of Chem ical Industries. L e t us consider w hether changes in plan could be m ade to advantage.
T he exposition serves as a m edium for th e exchange of ideas between exhibitors and th e purchasers of th eir prod
ucts. I t has an im p o rta n t educational function to perform , and it assists in creating th e p ro p er conception of th e chemical in d u stry in th e m inds of th e public.
W hile th e tendency has been to perform these services, we believe m uch rem ains to be accom plished. M any of th e exhibitors are ju st beginning to see th e possibilities of such an exhibition. O thers fail to find in th e present p lan enough to gain th eir fu rth e r su p p o rt. W e suggest therefore th a t th e tim e has come w hen th e four groups repre
senting th e in d u stry should be b rought into closer coopera
tion w ith th e exhibition m anagem ent an d th a t th e u n d er
tak in g should be m ade a cooperative project. T h e M an u facturing C hem ists’ Association, th e S ynthetic Organic Chem ical M anufacturers Association of th e U nited States, th e Association of Scientific A p p aratu s M akers, an d th e recently form ed Chem ical E q u ip m en t Association include th e m a jo rity of those who are directly and financially in
terested. W ith th is group could be associated as advisers representatives of scientific societies an d others in a position to contribute to th e success of th e exhibit.
W e should like to see an effort m ade to conduct an im per
sonal educational ty p e of exhibit w here th e public could be interested in th e science as a whole ra th e r th a n in in
dividual products. M a n y m ethods of tre a tm e n t suggest them selves in th is d ay of expert m odel m akers, motion pictures, and o th e r devices. E ith e r concurrently w ith th is exhibit or separately, th ere could be held a tech
nical exhibit for th a t portion of th e public, b o th buyer and seller, who can ap preciate th e stric tly technological phases of th e industry. T he first w ould be for th e purpose of education, th e second for th e purpose of im proving de
vices and obtaining orders.
M uch can be done to im prove th e com ing exposition if th e exhibitors will ta k e pains to place in th e ir booths m a
terials w hich will really con trib u te to th e in terest of th e show as a whole an d do som ething tow ard educating th e public.
587 I t is false econom y to invest com paratively large sum s in
space an d th e n fail to show products or dem onstrate proc
esses, an d especially to place in charge those who are not sufficiently well inform ed to represent th e exhibitor. In th e p a s t some exhibits have been in charge of m en incom pe
te n t to answ er questions an d m ake explanations. I t is very m uch like buying expensive advertising space an d th e n designating th e office boy to w rite th e copy. F irs t im pressions, w hether obtained th ro u g h th e ch aracter of th e exhibit or th ro u g h th e rep resen tativ e in charge, are likely to be lasting, and for several exhibitors th e exposition is their only contact w ith' a considerable p a r t of th e public.
Facts in Plain Words
/ ’"'H E M IS T S w ho read beyond th e ir own field have per-
^ h ap s seen th e p ap e r of George O tis S m ith, D irecto r of th e U. S. Geological S urvey, in Economic Geology for Ja nuary-F ebruary 1922. U nder th e cap tio n “ Science, th e Oracle,” D r. S m ith urges geologists to set fo rth facts in th e sim plest possible form , being convinced “ th a t a t its best, science is sim ple— th a t th e sim plest arrangem ent of facts th a t sets fo rth th e tr u th b e st deserves th e te rm scientific.”
D r. Sm ith uses several exam ples from geological lite ra tu re to show how frequently w ords are used for th e ir own sake, and th e failure of au th o rs to realize th e need of reaching their readers th rough w ords m ore easily understood th a n the technical phrases so dear to m a n y of us. T hus, “ ‘dis
sem inated’ and ‘disintegration’ are w ords th a t please every ear, train ed or untrain ed , w hile th e garden v arie ty of m ind is helped along b y th e plain w ords ‘sc a tte re d ’ an d ‘breaking up.’ ”
In chem istry it should be possible for us to sta te our facts in words sufficiently plain to m ake th e m easily understood w ithout introducing th a t extrem e form of p o p u la rity which is distasteful to m a n y scientific w riters. Plow often we fail to in te rest th e laym an in a su b ject w hich really concerns him, m erely because we p ersist in concealing our th o u g h ts behind a barrage of professional phrases. M o s t.o f us are pleased w hen wre find a d en tist, a physician, a lawyer, or a banker who w ill discuss his w ork w ith us in term s w hich we understand. If we desire to have our science understood and app reciated , o ught we n o t to be willing to do as m uch for them ?
O E V E R A L o f o u r p r e s i d e n t s h a v e h a d t h e o p p o r t u n i t y
^ t o v i s i t a n u m b e r o f S e c t i o n s o f t h e So c i e t y, b u t so f a r a s wre k n o w n o n e h a s t r a v e l e d m o r e w i d e l y i n t h e i n t e r e s t s o f t h e So c i e t y t h a n h a s P r e s i d e n t S m i t h . .W e h a v e f o llo w e d h i m i n s o m e p l a c e s a n d h a d t h e g o o d f o r t u n e t o b e w i t h h i m i n o t h e r s . I t is c e r t a i n t h a t h i s v i s i t s h a v e d o n e a g r e a t d e a l t o p r o m o t e t h e i n t e r e s t s o f t h e So c i e t y a n d t o a s s i s t c h e m i s t s i n e a c h l o c a l i t y . H i s d e l i g h t f u l d i s c u s s i o n s o f v a r i o u s p h a s e s o f h i s t o r i c a l c h e m i s t r y i n A m e r i c a h a v e g i v e n t h e y o u n g e r m e n i d e a l s t o w a r d w h i c h t o l o o k a n d t r a d i t i o n s o f e a r n e s t, c o n s t r u c t i v e w o r k t o u p h o l d . H e h a s u r g e d c o l l e g e s t o w r i t e t h e h i s t o r y o f t h e i r c h e m i c a l d e p a r t m e n t s n o w , w i t h a d d i t i o n s t o b e m a d e f r o m t i m e t o t i m e i n f u t u r e , s o t h a t s o m e f u t u r e h i s t o r i a n m a y h a v e b e t t e r f a c ili
tie s i n p a i n t i n g a t r u e p i c t u r e o f c h e m i s t r y i n A m e r i c a . H i s t a l k s w i t h t e a c h e r s a s w e l l a s w i t h s t u d e n t s h a v e b e e n i n s p i r i n g . P r e s i d e n t S m i t h h a s d o n e m u c h i n h i s t r a v e l s f o r c h e m i s t s a n d t h e Am e r i c a n Ch e m i c a l So c i e t y.
Scientific Research an Association Activity
T
T WAS recently our pleasant task to review before th e In stitu te of M argarin M anufacturers th e tendency in America to-dav for trad e associations to u n d ertak e scientific research as one of th eir productive activities. Am ong th e hundreds of trade associations in this country, m any of which engage upon wyork of standardization, there are some th irty - five w hich have become identified w ith p articu la r scientific problem s. These associations v ary between such extrem es as four and 12,500 members. T he budgets are supplied by assessm ent or contributions and are from S2500 to several hundred thousand dollars. W hile we have always m aintained th a t an industry derives th e greatest benefit from research w hen it is m ade a definite and adequately su p p o rted p a r t of its own organization, it is coming to be accepted th a t m an y fundam ental problems can be m ost thoroughly studied on a basis winch calls for cooperation am ong firms ra th e r th a n excessive expenditure b y a single corporation.
I t is encouraging to find several im p o rta n t associations originally organized for nonscientific activities tu rn in g to constructive plans for research and technical training. T h e experience of the associations th a t have been engaged in research for a num ber of years has encouraged others to ven
tu re upon programs of th eir own.
T he In stitu te of M argarin M anufacturers is developing plans for early attention.
T he In stitu te of American M e at P ackers is now consider
ing an am bitious plan w hereby it m ay become so organizad as to combine a research institute, an educational in stitu tion, and an industrial m useum w ith a tra d e association.
Those who heard th e address of M r. Thom as E. W ilson before the General M eeting of our So c i e t y a t Chicago will n o t be surprised to find him chairm an of th e P lan Commis
sion of th e Institute.
I t generally follow's th a t those who derive th e g rea test benefit from association research are those w ith th e b e st trained technical staff. To our m ind, th e ideal is th e con
tinuance of fundam ental research as a group p roject w ith th e utilization of its products by th e individuals of th e group, each according to his own needs and through his own scientific organization.
Dating Scientific Books
A
T T H E Birmingham M eeting th e Council passed a resolution calling upon publishers to p rin t th e d ates a t w hich chemical books are w ritten or revised ra th e r th a n th e d ate copyrighted or th e d ate printed, so th a t th e p u rchaser m ay have some guide in selecting recent co n trib u tions to th e literature. T his resolution has been sy m p a th e t
ically received on th e whole by th e publishers in our field.
M any publishers have expected readers to ascertain w hether a book has been revised by consulting th e copy
right d ate or th e date of th e la st preface. O thers designate a book as the first edition w ith a title page d a te b en e ath th e im print and continue to designate th is w ork as th e first edition w ithout change of title page date, using for exam ple, first edition, second impression, or th ird im pression as th e case m ay be, un til th e book is thoroughly revised. A t such tim e th e title page d ate is of course changed. T h is is obviously w hat we desire, and publishers should refrain from changing th e title page d ate w henever th e book is m erely reprinted.
Publishers, like other tradesm en, comply^ w ith any insis
te n t reasonable dem and. Book buyers can have books properly dated if they w'ant them .
T H E J O U R N A L OF 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. 14, No. 7
Engineering and Conservation Texts
n r i l E P A R T played b y research in conservation has been -*• th e subject of m any an article in w hich th e im portance of new studies h as been em phasized. T h e application of acquired knowledge in th e effort to conserve n atu ra l resources ought to be an established practice in engineering, b u t of late th e desire to reduce first costs appeal's to have led m any autom otive engineers aw ay from th is sound principle. I t is disturbing to find strong light-w eight m aterials being displaced by heavier ones in th e interests of low first cost w ithout regard to w h a t is involved in tran sp o rtin g th e greater w eight d u rin g th e life of th e car. In a certain well-known car a few dollars hav e been saved in construction a t an ex
pense of pow er efficiency estim ated b y different specialists a t from 20 to 50 p er cent. W hen th e nu m b er of these cars is m ultiplied b y th e am ount of fuel w hich could be conserved annually b y a slightly higher first expenditure, we are led to suggest legislation, if necessary, to com pel all m anufacturers of autom otive vehicles to include in th e ir designs such p rin ciples as experience has ta u g h t w ill co ntribute to d irect sav
ing of petroleum products.
T he indifference of autom otive engineers to th e problem of future fuels is well known. C ars are continually b u ilt as if gasoline as it used to be w ould la st forever. T h a t m ay hie justified because a gasoline su b stitu te has n o t been produced on a commercial scale, although m otorists know th e changing characteristics of w hat th e y buy as gasoline.
Realizing th e im portance of th e liquid fuel situation, the Soci6t<5 de Chim ie In dustrielle of F ran ce has called an In tern atio n al Congress on Liquid Fuels, to be held in Paris. F u rth e r inform ation is given on page 631.
So far as obtaining th e m axim um pow er from present fuels is concerned, th e question of saving a few dollars in construction should certainly be m ade subordinate, p ar
ticularly by those m anufacturers who claim to have exalted ideals w here public welfare is concerned.
f ^ U T IN T acom a th e Olympic Chem ical C lub has created an executive body of six m em bers to cooperate with o ther civic organizations in th e u p building of th e com m unity.
T his chemical engineering council for public w elfare ants independently of th e Olym pic Chem ical Club, b u t its m em bers are individually responsible to th e Club. T h e council will aid in th e establishm ent of desirable new industries, assist established industries in developing along sound an d proper lines, and be active in all m a tte rs rela tin g to h ealth .an d safety in which th e science of chem istry plays a p a rt. T h e educa
tion of th e public to a b e tte r ap preciation of chem istry, th e ethics of chem ists and chem ical engineers, th e protec
tion of th e public from being victim ized b y prom oters in m atters pertaining to chem istry, th e stu d y of local in d u strial resources in order th a t d a ta m ay be supplied to those in ter
ested in establishing industries are o th e r objects. O ther Sections and chcmical clubs m ay find it well w orth while to consider th is exam ple w hich th e y m a y wish to follow.
jL T A V E Y O U read th e preface w ritte n b y D r. E . E.
Slosson for th e revised edition of S m ith ’s “ In te rm e d ia te C hem istry?” In a few pages th is interestin g w riter has given us te x ts sufficient for a whole series of lectures scientifi
cally sound and p o pular in th e ir appeal. O r those who share th e view expressed b y W . L. L. in th e Chemical Bulletin for Ju n e m il find in th ese th o u g h ts suggestions for really scholarly addresses in w hich to teach about chem istry rath e i th a n to teach all m en chem istry.
"Chemistry is the science of power. All the energy of man and beast and all the energy of machinery, except that furnished by windmills and water wheels, is chemical energy and nearly all of this is derived from tw o simple and similar chemical re
actions, the oxidation of hydrogen to form water and of carbon to form carbon dioxide.”
"Chemistry has control of life and death. An animal or plant deprived for a tim e of the proper chemical compounds will starve or if it imbibes a minute am ount of the wrong chemical com
pounds it dies a t once.”
"Chemistry is the science of terror and p ity” for it provides both the materials for destruction and for healing. It is m an’s weapon against disease, insects, fungi, pain, and sleeplessness.
It tears down and builds up.
"Chemistry is the democratic science. I t bestows upon the poorest w hat once were the gifts of kings.” I t is the joyous science and contributes m ost to the pleasures of life. "Chem
istry is a practical science. N one touches everyday life at more points except its sister science, physics, between which and chem
istry no clear boundary can be drawn. N one has more avenues for profitable em ploym ent.”
B u t read th e preface an d consider th e possibilities of ar
ranging a p o pular course of lectures in chem istry in y o u r own com m unity!
E arning Power of Research
O O M E years ago engineers a t a cotton textile p la n t in-
^ troduced an air conveying system so th a t prepared fiber m ight be quickly an d cheaply tran sp o rted from one p a r t of th e im m ense p la n t to another. T h e system was successful u n til cold w eather came. T h e n th e m oisture in th e conveying air froze in th e pip e betw een buildings.
As th e m oisture froze, th e fibers becam e a ttac h ed an d soon stopped th e entire system . A fter surveying th e situation th e engineers concluded th a t th e conveyor m u st be sur
rounded w ith steam pipes to p rev e n t freezing. T h e cost w as estim ated a t 830,000. T h e re p o rt was m ade to the p resident in th e presence of th e chem ist, who required no research to u n d erstan d th e factors of th e problem . He recom m ended th a t th e fibers be conveyed in cold air drawn in from outside th e building and therefore of th e sam e rela
tive h u m id ity as th e air around th e conveyor. Although th e engineers p redicted it w ould n o t w ork, th is m ethod was tried and succeeded. T h e §30,000 w as saved th rough the observation of a chem ist. I t pays to have one around.
A L T H O U G H we travel as m uch as our budget will allow,
^ we can serve th e science and th e in d u stry to m uch b etter advantage if we can be k e p t inform ed regarding th e opinions, desires and accom plishm ents of individuals and I.ocal Sections in th e So c i e t y. I n an effort to achieve our id e al th e Local Sections have been asked to ap p o in t official sta ff correspondents for Th i s Jo u r n a l. O ur list is n o t y e t com plete, b u t th e nam es of th e correspondents who have been ap p o in ted are given on page 653.
T D E F O R E research developed accelerators for th e vul- canization of rubber, tw o to th ree hours were required to com plete th e process. M uch research still rem ains to be done upon organic accelerators b u t already results have been achieved w hich reduce th e rim e to a b o u t th irty minutes.
A nother w ay of sta tin g th is is to say th a t w ith th e intro
duction of accelerators one-third th e form er vulcanizing p la n t is required in a factory of a given size, an d th e capacity of th e entire p la n t has been doubled.
589
Detonation Characteristics of Blends of Aromatic and Paraffin Hydrocarbons1
By Thomas M idgley, Jr.,2 and T. A. Boyd2
Ge nBr a i, Mo t o r s Re s e a r c h Co r p o r a t i o n, Da y t o n, Oh i o
The fo llo w in g p a p e r presents the results obtained in a careful measurem ent o f the effects o f various concentrations o f benzene, toluene, or xylen e u p o n the detonation tendency o f para ffin fu e ls in badly carbonized or high com pression engines.
M ost o f the d eterm in a tio n s were m ade on blends w ith kerosene, on account o f its greater tendency to detonate. A s a sta n d a rd o f com parison, use was m ade o f paraffin fu e ls co n ta in in g s m a ll am ou n ts o f x ylid in e, w hich, in com m on w ith other arom atic a m in es, exerts a pow erful su p p ressin g action on detonation.
A sim p le basis fo r d eterm in in g the a m o u n t o f benzene necessary to add to a para ffin f u e l in order to obtain a given effect is as follow s:
Up to a concentration o f 70 per cent by m olecules, the effectiveness of benzene fo r su p p ressin g detonation Varies d irectly as the square o f its m olecular concentration {F ig. 3).
T
H E “ knocking” th a t is so fam iliar in autom obile engines w hen laboring on hills w ith wide open th ro ttle has com m only been a ttrib u te d to preignition. T his conception, however, h as been proved erroneous. T he“knock” u n d er such conditions is p ro b ab ly due to a de
tonation of p a r t of th e fuel charge, an d th e tendency of a fuel to d eto n ate is a function of its chem ical com position.
Furtherm ore, th e d eto n atin g ten d en cy of a fuel of given composition a n d stru c tu re varies w ith th e com pression to which it is subjected, w ith the effectiveness w ith w hich th e engine is cOoled, an d w ith th e degree of carbonization in th e cylinders of th e engine. T h e ten d en cy of a fuel to knock or detonate in a given engine is influenced also b y some elements of design, such as, for exam ple, th e sp a rk plug location.
I t has been know n for som e tim e th a t th e addition of ben
zene and certain o th e r arom atic hydrocarbons to paraffin- base gasolines g rea tly reduces th e ten d en cy of th e fuel to detonate w hen used in autom obile engines.
The extension of th e b y -p ro d u ct coking in d u stry in th e United S tate s d u rin g th e rec en t w ar g enerated a capacity for the production of lig h t oil w hich could only be absorbed by the use of a p a r t of th e m aterial as a m otor fuel. Since 1918, therefore, m ixtures of benzene (or “ m otor benzene” ) and blending n a p h th a h av e been ra th e r w idely sold as m otor fuels in th is country, a n d a t a b o u t th e sam e price as gasoline.
Veiy few accurate q u a n tita tiv e d a ta hav e been published on th e effect of th e blending of arom atic hydrocarbons w ith paraffin-base gasolines up o n th e tendency of th e la tte r to knock or d eto n ate. T h e p rim a ry reason w hy m ore of these fundam ental d a ta hav e n o t been obtained an d m ade gener
ally available is th e previous lack of a m eans for m easuring the d etonating te n d e n c y of fuels w ith sufficient accuracy.
A device has rec en tly been developed w ith w hich th e tendency of a fuel to d eto n ate can be determ ined w ith a high degree of accuracy an d reliab ility .3 T h e purpose of this paper is to presen t som e resu lts obtained in th e careful m easure-
1 P rese n ted before th e P e tro le u m S ectio n a t th e 6 3 rd M e e tin g of th e A m erican C h em ical S o ciety , B irm in g h a m , A la ., A pril 3 to 7, 1922.
2 Chief a n d A ss is ta n t C h ief of th e F u e l Sectio n o f th e G en eral M o to rs R esearch C o rp o ra tio n , D a y to n , O hio.
3 F o r a discussion of th e re la tiv e m e rits of th e v a rio u s m ean s th a t h av e been used for o b serv in g a n d m e a su rin g d e to n a tio n in engines see M id g le y a n d B oyd, “ M e th o d s of M ea su rin g D e to n a tio n in E n g i n e s /’ J . Soc. Autom otive E?ig., 10 (1922), 7.
m e n t of th e effects of various concentrations of different arom atic hydrocarbons upon the detonation ten d en cy of paraffin fuels in badly carbonized or high compression en
gines.
I n order th a t th e effects of arom atic hydrocarbons in as w ide a range of concentrations as practicable m ig h t be m eas
ured, they were blended w ith kerosene for m aking th e m a
jo rity of th e determ inations reported in' th is paper. T he g reater tendency of kerosene th a n lighter paraffin hydro
carbons to detonate m ade i t possible to determ ine th e de
tonation characteristics of blends u p to a concentration of 80 p er cent benzene w ithout introducing th e difficulties inci
d e n t to excessively high engine compressions.
Fi g. 1— Ap p a r a t u sf o r Me a s u r e m e n to f De t o n a t i o n b yt h e Bo u n c i n g Pi n Me t h o d
On account of variations in m otor conditions it is ev id en t th a t d a ta obtained from an y p articu la r engine are applicable in a quan titativ e w ay only to th a t one m otor design a n d se t of conditions. B ut, although w idely different behavior m a y characterize th e com bustion of a given fuel in twro engines, the relative behaviors of two given fuels will be com parative in w hatever ty p e of m otor th e y m a y be ru n . Hence, in measuring th e d etonating ten d en cy of a n y fuel it is essential th a t some sta n d a rd fuel be used as a basis of comparison. In th e tests reported herein sm all p erc en t
ages of xylidine, in th e sam e paraffin fuel as was used for blending w ith th e arom atic hydrocarbons, were em ployed as a standard. X ylidine has the p ro p erty , com m on to aro
m atic amines and considerably m ore m ark ed in a n um ber of o th e r m aterials, of exerting a powerful suppressing action on detonation, when present in a fuel in percentages th a t are
Vol. 14, No. 7
Ta b l b I — Ph y s i c a l Da t a o n Fu e l s Us b d i n Te s t s
A b so rp tio n in . Di s t i l l a t i o n Te m p e r a t u r e s, 0 C .1 .
S p . G r. C o ld HjSO« F ir s t
Hy d r o c a r b o n 15° C. P e r c e n t D ro p 10% 2 0 % 3 0 % 4 0 % 5 0 % 0 0 % 7 0 % 8 0 % 0 0 % 95% D ry
K e ro s e n e . ... ... 0 .8 1 6 7 1S6 201 207 212 2 1 7 .5 222 2 2 7 .5 2 3 3 .5 241 2 5 3 .5 268 291
C om m ercial g a so lin e ... 0 .7 3 4 5 40 05 8 3 .5 99 1 1 1 .5 125 140 1 5 7 .5 177 200 219 226
" H ig h T e s t - g a s o l i n e ... 0 .7 0 4 3 44 59 6 S .5 76 8 2 .7 8 9 .3 90 103 114 12S 157 178
Benzene (90° b e n z e n e )... 0 .8 7 8 . . 74 7 7 .5 7 8 .7 7 9 .2 7 9 .8 8 0 .1 8 0 .5 8 1 .1 82 85 92 5 T o lu e n e ... 0 .8 6 0 (a b o u t) . . 107 108 1 0 8 .5 1 0 S .6 1 0 8 .7 1 0 8 .8 1 0 8 .8 1 0 S .8 1 0 8 .9 109 109^2 X y le n e ... 0 .8 6 0 (a b o u t) . . 135 136 1 3 0 .2 1 3 6 .5 1 3 6 .7 1 3 6 .9 1 3 7 .1 1 3 7 .3 1 3 7 .5 1 3 7 .S 1 3 8 .1 . .
„ 1 a p p a r a tu s u s e d co n fo rm e d a p p ro x im a te ly to th e s ta n d a rd of th e C o m m itte e fo r th e S ta n d a rd iz a tio n of P e tro le u m S p ecificatio n s a s g iv en in th e ir Bulletin 5, p u b lish e d b y th e U. S. B u re au of M in es.
relatively very sm all. T h u s, it m a y be seen from Fig. 2 th a t 1 p er ce n t of xylidine in kerosene is e q u iv ale n t for th e elim ination of d eto n atio n to a b o u t 15 p er ce n t of benzene in th e sam e fuel. T his p ro p e rty of th e m a teria l m akes it possible to co n v ert kerosene into a fuel th a t will w ith stan d very high com pressions w ith o u t knocking, an d th is w ith th e addition of such a sm all percentage of xylidine t h a t th e com
bustion characteristics of th e fuel, o th e r th a n its tendency to d eto n ate, are n o t m a teria lly changed.
Pr o p e r t i e s o f Ma t e r i a l s Us e d a s Fu e l s
T h e m a teria ls used as ingredients of th e v arious fuels th a t were e ith er exam ined o r em ployed as sta n d a rd s in th e exam inations w ere “ high te s t” gasoline, com m ercial gasoline, kerosene, xylidine, benzene (90° benzene), toluene, and xylene. T h e xylidine em ployed w as a com m ercial m aterial, composed of th e m ixed xylidines. Some physical properties of th e o th e r m aterials are ta b u la te d in T a b le I.
Ap p a r a t u s
A 3/ 4-kw. D elco-L ight engine w as used for m aking all th e determ inations. T h is is a single cylinder, air-cooled engine, d irectly connected to a 32-volt d. c. g enerator, an d having a 2.5-in. bore and a 5-in. stroke. T h e engine w as sta n d a rd
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100 3 0 3 0 70 60 <30 4 0 3 0 2 0 10 0 PARAFFIN Pe r c e n t b y Vo l u m e
2 Gr a p h i c a l Re p r e s e n t a t i o n o p Da t a Ob t a i n e d i n De t e r m i n a t i o n o p De t o n a t i o n Ch a r a c t e r i s t i c so p Bl e n d s o p Ar o m a t i ca n d
Pa r a f f i n Hy d r o c a r b o n s
(P lo tte d fro m d a ta in C o lu m n s 4, 5, a n d 7 ; T a b le s I I , I I I , IV , a n d V)
in every w ay, except th a t th e m ixing valve was bored to a larger inside diam eter, th a t a m eans was provided for ad
ju stin g th e sp a rk tim ing, an d th a t th e com pression was in
creased b y stages from th e n orm al ra tio of 3.47 : 1 to a ratio of 5.36 : 1, b y m eans of a series of cylinder heads w hich had been cu t dow n by different am o u n ts so as to reduce th e clear
ance volum e b y corresponding stages.
T h e device th a t w as em ployed for m easuring th e relative intensities of different detonations, an d called th e “ bouncing p in ” ap p a ra tu s, is show n d iagram m atically in Fig. 1. An essential p a r t of th is device is a com bination of a bouncing pin w ith th e sta n d a rd p ressure elem ent of th e M idgley In d ic a to r.’1 T h is pressure elem ent is designed to screw directly into th e com bustion cham ber a n d to come flush w ith th e inner surface of th e cylinder head. T h e low er end of th e elem ent em bodies a sm all piston, th e upwTard move
m e n t of w hich is resisted b y a h ea v y spring. I n th e original elem ent th e m ovem ent of th e piston resu ltin g from pressure changes in th e com bustion cham ber is tra n s m itte d through a v ery lig h t ro d to a n arm w hich o p erates to change th e v erti
cal angle of a sm all m irror, su p p o rted on a horizontal axis a t th e to p of th e elem ent, in pro p o rtio n to th e pressure on th e piston. I n th e bouncing pin a p p a ra tu s th e m irror and th e sh a ft connecting i t to th e p isto n hav e been replaced by a h ea v y pin w hich re sts on th e p isto n sim ply b y gravity.
D uring n orm al com bustion th is pin m oves u p a n d dow n very slightly (only a few th o u sa n d th s of an inch), owing to its following th e m ovem ent of th e piston resulting from norm al pressure changes in th e cylinder. B u t w hen detonation occurs in th e com bustion cham ber th e ro d ju m p s upw ard a noticeable distance a n d entirely clear of th e piston. The am plitude of m ovem ent of th e pin varies w ith th e intensity of detonation. I t h as been observed to ju m p as high as 1.5 in. above its norm al position.
Since tw o successive explosions in a cylinder are rarely exactly alike, th e desired degree of accuracy could n o t be obtain ed w ith o u t a n in te g ratio n of th e flu ctuations of th e pin over a period of tim e. T h e re s t of th e a p p a ra tu s illus
tr a te d in F ig. 1 w as arranged to accom plish th is result.
C o n ta c t p o ints w ere held in position in a n electric circuit b y springs im m ediately above th e u p p er end of th e bouncing pin, in such a w ay as to be closed w hen th e p in w as throw n free of th e piston. A n in te g ratio n of th e le n g th of tim e th e co n tac t p o in ts w ere closed w as th e n o b tain ed b y m easuring th e volum e of gas evolved during a 1-min. period b y an elec
tro ly tic cell placed in series w ith th e points. T o th e cell, w hich contained a 10 per cen t solution of sulfuric acid in distilled w ater, 110 volts d irec t cu rre n t w ere applied through a resistance u n it, th is high voltage being used to reduce polarization. P la tin u m electrodes w ere used in th e cell which, as is show n in Fig. 1, w as designed so th a t th e evolved gas w as au to m atica lly collected in a slender g ra d u a te d tu b e a t th e to p w here its volum e could be easily noted. Since th e am o u n t of gas evolved during a given period b y one fuel was always com pared w ith th a t evolved b y a fuel of sim ilar deto n atio n characteristics t h a t w as ru n im m ediately before and a fte r it, no correction of th e volum e of gas w as m ade for
4 F o r d e sc rip tio n o f th is p re ssu re e le m e n t a n d its fu n c tio n see “ H igh S peed In d ic a to rs ,” b y T h o m a s M id g ley , J r ., T ra n s. Soc. Autom otive E n g ., 15 (1920), 317.
T U E J O U R N A L OF 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 591
Ta b u s I I — Da t a Ob t a i n e d i n De t e r m i n i n g De t o n a t i o n Ch a r a c t e r i s t i c so f Va r i o u s Bl e n d so f Be n z e n ea n d Ke r o s e n e De t e r m i n a t i o n
Nu m b e r 12 20 21 1 315
1 6 11 22 2 3 2 8 2 9 10 3 7 3 8 3 9 4 0 4 1 4 2
C o m p ressio n R a tio
3 . 4 7 3 . 4 7 3 . 4 7 3 . 4 7 3 . 4 7 3 . 4 7 3 . 8 7 3 . 8 7 3 . 8 7 4 . 5 9 4 . 5 9 5 . 3 6 5 . 3 6 5 . 3 6 5 . 3 6 5 . 3 6 5 . 3 6 5 . 3 6
S p a rk , D egrees b efore T . D . C.
4 3 4 3 4 3 4 3 4 3 4 3 4 3 4 3 3 2 3 2 2 5 2 5
2 5 2 5
Be n z e n e-Ke r o s e n e Blend
B en zen e K erosene
P e r c e n t b y Vol. P e r c e n t b y Vol.
De t e r m i n e d Eq u i v a l e n t Xy l i d i n s i n Ke r o s e n e, Pe rc e n tb y Vo l u m e 15
15 1 5 2 5 2 5 2 5 4 0 4 5 4 5 5 5 5 5 7 0 7 0 7 0 7 0 8 0 8 0 8 0
8 5 8 5 S 5 7 5 7 5 7 5 6 0 5 5 5 5 4 5
’ 4 5 3 0 3 0 3 0 3 0 20 20 20
In d iv id u a l 1.0 1.0 1.0 2 . 0 5 1 . 9 5 2 . 2 5 4 . 3 4 . 7 4 . 7 7 . 0 5 7 . 0 5 1 0 . 6 5 1 1 . 3 1 1 . 5 1 1 . 4 1 5 . 8 1 5 . 8 5 1 5 . 8 5
A verage
1.0
2.1 4 . 3 4 . 7 7 . 0 5
11.2
1 5 . 8
Ta b l e I I I — Da t a Ob t a i n e d i n De t e r m i n i n g De t o n a t i o n Ch a r a c t e r i s t i c so f Va r i o u s Bl e n d so f To l u e n ea n d Ke r o s e n e To l u e n e- Ke r o s e n e Bl e n d De t e r m i n e d Eq u i v a l e n t Xy i De t e r m i n a t i o n C o m p r e s s i o n S p a r k , D e g r e e s T o l u e n e K e r o s e n e i n Ke r o s e n e, Pe rc e n tb y Vc Nu m b e r R a t i o b e f o r e T . D . C . P e r c e n t b y V o l. P e r c e n t b y V o l. I n d i v i d u a l A v e r a g e
1 7 3 . 4 7 4 3 2 0 8 0 1 . 8 1 . 8
1 4 3 . 4 7 4 3 2 5 7 5 2 . 5 5 2 . 5 5
2 4 3 . S 7 4 3 4 5 5 5 5 . 2 5
2 5 3 . 8 7 4 3 4 5 5 5 5 . 3 5 5 . 3
3 0 4 . 5 9 3 2 5 5 4 5 7 . 4
3 1 4 . 5 9 3 2 5 5 4 5 7 . 1 5
3 2 4 . 5 9 3 2 5 5 4 5 7 . 1 5 7 . 2 5
4 5 5 . 3 6 2 5 7 0 3 0 1 1 . 7 5
4 6 5 . 3 6 2 5 7 0 3 0 1 1 . 9 1 1 . 8 5
4 3 5 . 3 6 2 5 7 5 2 5 1 4 . 4 1 4 . 4
Ta b l e I V — Da t a Ob t a i n e d i n De t e r m i n i n g De t o n a t i o n Ch a r a c t e r i s t i c s o f Va r i o u s Bl e n d so f Xy l e n ea n d Ke r o s e n e Xy l e n e- Kij r o s e n e Bl e n d De t e r m i n e d Eq u i v a l e n t Xy l i d i n e De t e r m i n a t i o n C o m p r e s s i o n S p a r k , D e g r e e s X y l e n e K e r o s e n e i n Ke r o s e n e, Pe r c e n tb y Vo l l
Nu m b e r R a t i o b e f o r e T . D . C . P e r c e n t b y V o l . P e r c e n t b y V o l. I n d i v i d u a l A v e r a g e
1 8 3 . 4 7 4 3 2 0 8 0 1 . 8
1 9 3 . 4 7 4 3 2 0 8 0 2 . 0 5 1 . 9 5
2 6 3 . 8 7 4 3 4 5 5 5 6 . 0 5
2 7 3 . 8 7 4 3 4 5 5 5 6 . 0 5 6 . 0 5
3 3 4 . 5 9 3 2 5 5 4 5 7 . 7 5
3 4 4 . 5 9 3 2 5 5 4 5 7 . 8 0
3 5 4 . 5 9 3 2 5 5 4 5 7 . 8 5 7 . 8
4 7 5 . 3 6 2 5 7 0 3 0 1 2 . 2
4 8 5 . 3 6 2 5 7 0 3 0 1 2 . 7 1 2 . 4 5
Ta b l e V — Da t a Ob t a i n e d i n De t e r m i n i n g De t o n a t i o n Ch a r a c t e r i s t i c so f Bl e n d so f Be n z e n ea n d Ga s o l i n e
De t e r m i n a t i o n Nu m b e r
5 9 6 0 6 3 6 4 61 6 2
C o m p ressio n R a tio
5 . 3 6 5 . 3 6 4 . 5 9 4 . 5 9 5 . 3 6 5 . 3 6
Be n z e n e- Ga s o l i n e Bl e n d
S p a rk , D eg rees B enzene /--- G aso lin e ; - b efore T . D . C . P e r c e n t b y Vol. P e r c e n t b y Vol. D esignation
2 5 2 5 3 2 3 2 2 5 2 5
5 0 5 0 2 5 2 5 2 5 2 5
5 0 5 0 7 5 7 5 7 5 7 5
Cora, gasoline Com . gasoline C ora, gasoline C om . gasoline H . T . gasoline H . T . gasoline
De t e r m i n e d Eq u i v a l e n t Xy l i d i n e i n Ga s o l i n e, Pe r c e n t b y Vo l u m e
In d iv id u a l A verage 5 . 0
5 . 1 5 . 0 5
1 . 7
1 . 8 5 1 . 8
1 . 6 5
1 . 6 5 1 . 6 5
tem p eratu re or for th e slight liquid pressure resulting from the design of th e a p p a ratu s.
A ra p id an d com plete change of th e fuel entering th e engine when desired w as fac ilita te d b y th e use of a special fuel sys
tem . T h is device consisted of tw o ca rb u re to r float bowls, so arranged as to be a d ju sta b le for v ertical position, a n d two v ertical glass tu b e s placed side b y side, each connected a t its b o tto m to one of th e float bowls. E ac h of these tu b e s was connected in tu rn to a 3-way stopcock from w hich a single fuel line of sm all d ia m eter ra n to th e engine. T h is arrangem ent p e rm itte d ra p id sw itching from one fuel to an o ther m ain ta in ed a t th e p ro p er level to give th e correct am ount of fuel to th e engine. A m ixing valve, w hich was stan d ard , except th a t i t w as bored to a larger in te rn al diam eter, was used for m eterin g th e fuel to th e engine; so th a t in changing fuels no com plication was intro d u ced from th e residual fuel th a t rem ained in th e float bowl of a carburetor.
A m eans w as provided for th e com plete draining of th e p a r t of th e fuel sy stem n o t in use, so as to p erm it th e rea d y su b s titu tio n of different fuels.
Me t h o d
T h e m eth o d of m aking th e d eterm inations can b est be explained b y giving a specific example, for w hich th e com
parison of a 45 per cent benzene-55 p er cen t kerosene blend w ith fuels composed of sm all percentages of xylidine in kerosene will be employed. A com pression ratio of 3.87 w as used, so th a t some detonation would occur, b u t w hich wras n o t so violent as to cu t down seriously th e pow er of th e engine or to cause it to operate in an erratic m anner. T h e fuel under exam ination was p u t into one side of th e fuel system , and the mixing valve on th e engine w as a d ju ste d so as to give a m axim um of detonation, w hich is an a d ju st
m en t th a t lies close to th e leanest possible m ixture for m axi
m um power. B y trial it was found th a t 5 per cen t of xylidine in kerosene had a very slightly lesser d eto n atin g ten d en cy th a n th e benzene-kerosene blend u n d er exam ination. T his fuel was then placed in th e o th e r side of th e fuel system , and its level was adjusted so as to give th e p o in t of m axim um detonation. T he setting of th e m ixing v alv e w as le ft u n disturbed throughout th e d eterm ination so th a t th e com
pression pressure of th e engine w ould be unchanged. A num ber of altern ate 1-min. ru n s w ere th e n m ade w ith th e 5 per cent xylidine in kerosene an d th e 45 p er ce n t benzene- 55 per cent kerosene blend, an d th e a m o u n t of gas evolved in th e electrolytic cell during each period w as recorded.
T he o u tp u t of th e generator on th e p la n t in v o lts and am peres was also kept, sim ply as a m a tte r of record. A fter from
