I/EC
Reports
THE EDITORS ANALYZE A N D INTERPRET THE CHEMICAL WORLD THIS M O N T H
Chemical Capsules Never Forget W o r k on carbonless carbon p a p e r points to possible chemical memory for computers VrfOMPUTERS seem well on their way to becoming an integral part of the chemical world. And it appears now that certain chemicals could become integral parts of computers. Specifically, National Cash Register's work with its carbonless carbon paper, now a multimillion dollar business, contains the germ of an idea for a chemical memory device. In fact, it's no longer just a germ ; N C R is working on it in a preliminary way. C o m p u t e r memory devices are basically switching devices. These can be electromechanical, like relays, or electronic, like vacuum tubes, transistors, and magnetic cores. N C R bases its chemical a p p r o a c h on the very closely controlled emulsification process worked out for use on its duplicating paper. T h e idea, there, was to make a colorless, oil-soluble dye react with a claylike material to give a bluish green color. N C R had to put these two phases on paper so that they would get together and react only when the user wanted them to—namely, when he was making " c a r b o n " copies. Doing this took some evolution, and N C R will not be specific on either the compounds or the process it uses. But the principle is to coat drops of the oil containing the dye with a gelatinlike material. The.se droplets a m o u n t to tiny, discrete capsules with high stability. Their size can be controlled closely; those used on N C R ' s duplicating paper are in the 2- to 3-micron range. Each sheet of duplicating paper
bears a film of capsules on one side, a film of the claylike material on the other. I n use, the paper is stacked so that a claylike surface is always next to a capsule surface. Pressure from pencil, pen, typewriter key, and the like breaks the capsules at the point of impact, releasing the dye. It reacts with the claylike coating on the adjacent sheet to give a " c a r b o n " copy. T h e chemical memory device would use the capsules, but without breaking them. Instead, they would contain a photosensitive dye which changes color when exposed to light of a certain wave length. (Capsule walls would be transparent to the light.) T h e dye returns to its original color when exposed to another wave length, remains unchanged in either color state when exposed to " n e u t r a l " wave lengths. N C R finds it can encapsulate such dyes and put a film of capsules on paper and other surfaces. This memory surface would act something like magnetic tapes and cores, which store information as magnetized spots. Light of the proper wave length would hit the coated surface, producing a colored spot. Light of another wave length would " e r a s e " the information by returning the spot to its original color. Light of a neutral wave length would " r e a d " the information stored on the surface. W h e t h e r reflected by the surface or transmitted through it, the neutral beam's characteristics would respond to the color pattern— the stored information—on the surface. These effects, boosted by photomultiplier circuits, would be translated to electronic signals for use by other circuits in the computer. As the capsules can be m a d e very small, millions of them could be put on a square inch of surface. Size of the memory spots, however, is limited by optical resolution rather than capsule size. Despite this situation, N C R believes high capacity might be one advantage of such a memory device. Another advantage might be relatively low cost. How-
ever, both of these presumptions— especially the one on cost—depend on the outcome of problems yet unsolved. These problems are m a n y and complex. I n general, they concern development of suitable input-output systems to complement the chemical memory surface. While NCR thinks they can probably be solved, it believes the first practical chemical memory or switching device of this kind is still some time in the future. K.M.R.
Isomerization: Key to High Octane Fuels of Tomorrow Refiners may face problems in making t o morrow's premium gasolines; new processes may be needed to match high octane—high compression ratio trends ISOMERIZATION processes to make high octane motor fuel components may be in wide use in the next few years. This prediction is m a d e freely by m a n y in the petroleum industry. Reason for their outlook: Some refiners m a y have severe problems in making p r e m i u m grade gasolines in the 100 or above octane range, should the present octane and auto compression ratio trends continue : • Premium gasoline octanes averaged 98.2 in June (F-1 Research method); expected to reach 103 by 1961 and average 105 by 1966. One source predicts octanes may near 110 by 1960. • Auto engine compression ratios average 9 to 1 now; expected to average 11 to 1 by 1961 T o d a y some 6 % of cars in use have compression ratios around or VOL 49, NO. 8
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AUGUST 1957
23 A
I/EC
REPORTS
ISOMERIZATION:
This is Standard Oil's (Ind.) version of isomerization, termed Isomate
above 10 to 1. And the percentage is expected to increase rapidly the next few years. This trend has tossed the petroleum industry into a state of flux. Refiners can't agree on ways to make a n d sell motor fuels ι which will satisfy (prevent knock) today's highest compression cars. Disagreement led to the threegrade marketing trend started by Esso last year (C&EN, J u n e 10, page 14). Sunoco has another idea —custom blending at the service station. O t h e r oil companies claim today's cars can be satisfied by improved traditional p r e m i u m grade gasolines. Although oil firms disagree on marketing practices now, a n d at least two refiners believe that octane and compression ratios have reached a plateau, there is general agreement that the high compression-high oc tane trends will continue. This will make problems for some re finers. H o w can they make, in sufficient volume, the predicted high octane fuels to meet needs for exexpected high compression ratio autos? H i g h octane needs the past few years have come mostly from cata lytic cracking, catalytic reforming, and alkylation. T h e future will see a need for improved processes plus new ones, claim many oil company spokesmen. O n e process being stud ied closely now is isomerization. 24
A
It is claimed as the next answer to higher octane motor fuels. Isomerization is a way to upgrade straight-chain paraffins, such as npentane a n d w-hexane, into iso forms. As such these products be come high octane motor fuel com ponents. No refiners use isomerization today directly for motor gasolines, but two companies are believed to be installing capacity. Five companies will license isomerization processes: Universal Oil Products, Penex ; Pure Oil, Isomerate; M . W . Kellogg, Iso-Kel; Atlantic Refining, Pentafining; a n d S t a n d a r d Oil (Ind.), Isomate. (There are three other isomerization processes available, but these usually u p g r a d e η-butane into isobutane for use as a feed stock in alkylation units. Hence these are a n indirect, not a direct w a y to higher octane fuels.) T h e five direct isomerization proc esses were developed or improved during the past year. All are con tinuous. Noble metals or aluminum chloride are usually the catalyst. Reaction conditions vary widely: temperature from 200° to 900° F . ; pressures from 150 to 850 pounds per square inch; residence time from 10 to 40 minutes. Typical feed stocks include straight-run n a p h thas or natural gasoline. Process yields are above 9 5 % . E n d prod uct rates from 93 to 107 octane (F-l Research method) with 3 cc.
INDUSTRIAL AND ENGINEERING CHEMISTRY
of tetraethyllead. Investment costs vary from $300 to $500 per barrel of capacity a n d depend upon both size and type of fractionation equip ment used or needed. W i t h five processes commercially available, there will naturally be variations which each licensee feels· will make the better process. But octane increase comes from convert ing n-pentane and n-hexane to isopentane, methylpentanes, and dimethylbutanes. T h e reaction is us ually rapid and approaches chemi cal equilibrium. O c t a n e numbers, therefore, are controlled by equi librium composition and also by temperature. Isomerization processes available can use either high or low reaction temperatures. W i t h high tempera tures fractionation and product re cycle are often needed to improve octanes. Initial product conversion varies considerably depending upon feed stock and the process (it is 60 to 8 0 % for C 6 's). Low tem peratures reduce recycling needs and, in some cases, eliminate it entirely. Here's how one process—• Isomate—works. I t was described by H . G. K r a n e , S t a n d a r d Oil (Ind.), at the American Petroleum Institute Division of Refining meet ing in Philadelphia last M a y . I n the Isomate process a n a p h t h a feed is first deisopentanized then dried and sent to a n absorber, where (Continued on page 26 A)
DRY A I R . . . PRECISELY as you w a n t i t pV t o c o n t r o l your p r o d u c t ' s quality pV t o p r e v e n t c o n d e n s a t i o n o n y o u r p r o d u c t o r material •
t o p r e v e n t c h a n g e s d u e t o moist air in c o n t a c t with your p r o d u c t
pV t o p r o t e c t y o u r m a t e r i a l from d a m p n e s s •
t o p r o t e c t y o u r p r o c e s s i n g o f moisture-sensitive material
•
t o D R Y y o u r material o r p r o d u c t
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t o p a c k o r store y o u r p r o d u c t safe from m o i s t u r e damage
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t o g e t exact m o i s t u r e c o n t r o l for t h e precise a t m o s p h e r e c o n d i t i o n y o u need
pV* t o p r o v i d e precise a t m o s p h e r i c c o n d i t i o n s for testing •
t o increase your air c o n d i t i o n i n g capacity
)V t o D R Y large quantities o f fresh air from o u t d o o r s
The Niagara's Controlled Humidity Method using HYGROL moisture-absorbent liquid is Bast and most «ffecttve because . . . it re moves moisture as a separate function from cooling or heating and so gives a precise result constantly and always.
of moisture remaining in the leaving air. Heating or cooling is done as a separate function.
Most reliable because . . . the absorbent is continuously reconcentrated automat ically. No moisture-sensitive instruments are required to control your conditions. Most flexible because... you can obtain any condition at will and hold it as long as you wish in either continuous produc tion, testing or storage.
IEC
REPORTS
it picks u p hydrogen chloride. Dis solved HC1 activates t h e catalyst (an a l u m i n u m chloride-hydrocarbon complex). N a p h t h a now enters the reactor at 200° to 250° F. a n d 700 to 850 p.s.i., along with 60 to 100 cubic feet of hydrogen per barrel (to suppress cracking and catalyst con tamination). Reactor effluent is cooled a n d flashed into a settler where entrained catalyst is separated. T h e liquid product is then stripped of hydrogen chloride, cooled, washed, a n d stabilized. Gases from the settler a n d stripper, along with some make-up hydrogen chloride, are recycled to the absorber where HC1 is redissolved. Excess hydro gen which passes through the a b sorber c a n be used either for fuel or for hydrogénation. T h e once-through product from the Isomate process is a high octane light n a p h t h a ready for use in blending premium motor fuels. T h e pentane fraction rates about 103 octane (3 cc. of T E L ) a n d the hexane fraction about 94. Combined final product octane runs from 96 to 98. W h e n a further octane increase is desired, t h e once-through product is fractionated a n d the lowoctane hexane isomers are recycled. Higher octanes c a n also be obtained by fractionating a n d recycling w-pentane from the overhead product of any primary fractionator. I t is possible to make products which range u p to 106 octane number. W.S.F.
fastest to t a k e care of because . . . the
apparatus is simple, parts are accessible, controls are trustworthy. The cleanest because . . . no solids, salts or solutions of solids are used and there are no corrosive or reactive substances.
AT THE
CHEMICAL
SHOW
26th EXPOSITION OF CHEMICAL INDUSTRIES Coliseum. New York City. December 2 - 6 . 1957
This method removes moisture from air by contact with a liquid in a small spray chamber. The liquid spray contact tem perature and the absorbent concentra tion, factors that are easily and positively controlled, determine exactly the amount Write for full information;
Brine Purifies Brines
See N I A G A R A AIR C O N D I T I O N E R S · A e r o H E A T E X C H A N G E R S Aero
AFTER
COOLERS
CONDENSERS Aero
ask for Bulletins
VAPOR
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Aero
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Aero
REFRIGERANT
STEAM
CONDENSERS
CONDENSERS
HEATERS
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COOLERS
•
HUMIDIFIERS
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DRYERS
In the osmionic cell, differences in salt concentration provide the power source
B O O T H N o . 655
ρ ERMSELECTIVE
112 and 121. Address Dept. EC
N I A G A R A BLOWER COMPANY 4 0 5 Lexington Ave., N e w York 17, Ν. Υ. District Engineers in Principal Cities of U. S. and
Canada
membrane
{Continued on page 28 A) Fsr farther information, circle number 26 λ on Renders' Service Card, page 101 A 26 A
INDUSTRIAL A N D ENGINEERING CHEMISTRY
proc
esses for purifying salt waters make u p one of the most promising areas screened for development in the Government's saline water conver sion program. O n e of these proc esses, "osmionic demineralization," requires no electricity. It makes use of osmotic pressure to move ions
