IEC
REPORTS
veloped for titanium and beryllium. Other processes of this type might eventually be used for other metals, such as zirconium. In the aluminum process—which is most useful for recovering pure metal from scrap, but which might also be applied to primary extraction·—aluminum trichloride is passed over impure aluminum. The following equilibrium reaction is set u p : 2A1 + A1G1, :
3A1C1
The gaseous aluminum monochloride is drawn off from the impurities, and then reverts to aluminum trichloride and purified aluminum. The trichloride is recycled. This process has been operated at Fulmer Research Institute on a small pilot-plant scale, and is being tried in a large-scale pilot unit in Canada. The small-scale plant consists of a tube about 15 feet long and 6 inches in diameter. Impure scrap is placed in refractory boats at one end of the furnace, and heated. Vaporized aluminum trichloride is passed over it. Further along, in a cooler por-
tion of the tube, aluminum condenses out on graphite containers. The condensed metal is very pure aluminum. Some research has also been done using fluorides and bromides, and a subhalide process was also investigated in Germany during World War II—chiefly for scrap recovery. In the U. S., the Bureau of Mines has worked for several years on an electric furnace method for converting raw aluminum silicate directly into aluminum-silicon alloys. Recently they have looked at the subhalide process as a way of getting pure aluminum from the alloy. Corrosion and other difficulties of working at high temperature will have to be overcome, and it is too soon to say whether the process will be economical. Alcoa is also interested in the subhalide process, but adds "high initial capital investment" to the other problems mentioned above. In the titanium process, titanium tetrachloride is passed over titanium alloy and a mixture of lower chlorides
is formed. Like aluminum monochloride, they revert to metal and the higher chloride. This process can be used for removing titanium from ferrotitanium—obtained from ilmenite. Today, most titanium comes from rutile (Ti0 2 ). Ilmenite is more plentiful and would be a valuable titanium ore if titanium could be extracted from it economically. The process for purifying beryllium is less similar to the aluminum process. Sodium chloride, rather than beryllium chloride, reacts with the metal. Be + 2NaCl *=£ BeCl2 + 2Na This process makes it possible to distill pure beryllium from an impure material. The beryllium and sodium chloride react and the reaction products are distilled off, leaving impurities behind. On condensation of the distillate, the reverse reaction takes place, leaving pure beryllium and salt, which can be easily separated from each other. A.S.H.
Versatile Boron Rags to riches element literally comes down to earth—via new boron steel IIGH-FLYING
N e w boron-containing cast carbon steel is made here b y Harrison's acid o p e n hearth process
Dark section shows d e p t h o f hardness in sprocket made o f Boralloy 28 A
INDUSTRIAL AND ENGINEERING CHEMISTRY
BORON, glamor
boy
among jet and rocket fuels, has come back to earth for a new use. Although a specialized application, its role in lengthening the life of crawler tractor sprockets on earthmoving equipment is another example of boron's spectacular versatility. Boron didn't get into this earthy work voluntarily. It took Caterpillar Tractor and Harrison Steel Castings a couple of years to convince the element that it has a place with the mundane. The 2-year interval was needed to develop a commercially successful acid-hearth process for boron containing cast carbon steel. Until the joint program was started in 1955, boron was added to steel almost entirely via the basic electric furnace process. Boron is wanted in steel because, in minute amounts, it improves (Continued on page 30 A)
I/EC
DRY AIR · · · PRECISELY as y o u w a n t i t •
t o c o n t r o l y o u r p r o d u c t ' s quality
•
t o prevent condensation o n your product or material
•
t o p r e v e n t c h a n g e s d u e t o m o i s t air in c o n t a c t w i t h y o u r p r o d u c t
•
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 protect your processing of moisture-sensitive material
•
t o D R Y your material o r product
•
t o p a c k o r s t o r e y o u r p r o d u c t safe from m o i s t u r e d a m a g e
•
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 condition you need
^
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 t e s t i n g
•
t o increase y o u r air c o n d i t i o n i n g capacity
^- t o D R Y l a r g e q u a n t i t i e s 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 Best and most effective 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. N o 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. Easiest to t a k e
care of because . . . t h e
REPORTS
d e p t h of hardness resulting from heat t r e a t m e n t . I n W o r l d W a r I I , for example, use of boron in cast steel t a n k a r m o r a n d transmission cases gave a considerable d e p t h of hardness after heat treating, thus conserving supplies of critical alloys. Caterpillar felt t h a t sprocket life would be d o u b l e d or better if t h e right alloy could be found. Boron's competitor h e r e w a s m o l y b d e n u m , but t h e boron steel was so promising t h a t other approaches were d r o p p e d . T h e n e w alloy, d u b b e d Boralloy, gives a hardness d e p t h 2.5 times greater t h a n straight c a r b o n steel m a d e t h e same way. W h y acid open h e a r t h instead of electric furnace? T w o reasons, says H a r r i s o n — b e t t e r control of the melt ing process a n d greater productive capacity of t h e company's open hearth. O n c e Boralloy was proved success ful, Caterpillar even changed t h e p a t t e r n of t h e sprockets to provide enough m e t a l section to use t h e full d e p t h of hardness. Caterpillar takes all of Harrison's Boralloy production, a n d for t h e time being, t h e steel castings c o m p a n y has n o plans to m a r k e t t h e alloy for other uses. Conceivably t h o u g h , a n alloy of this kind could be used whenever its hardness d e p t h is desirable. T h e whole o p e r a t i o n w o n ' t m a k e m u c h of a d e n t in t h e nation's supply of boron. B u t even t h o u g h it makes u p less t h a n 0 . 0 0 5 % of t h e steel's composition, m a y b e boron c a n con sole itself t h a t it's a miracle worker of sorts here, too. C.P.
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
C H E M I C A L
S H O W
26th EXPOSITION OF CHEMICAL INDUSTRIES Coliseum. New York City. Oecember 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;
See NIAGARA . . . AIR CONDITIONERS · Aero HEAT Aero AFTER COOLERS · Aero CONDENSERS · Aero STEAM Aero VAPOR CONDENSERS · HEATERS · COOLERS · BOOTH No. 655
ask for Bulletins
EXCHANGERS REFRIGERANT CONDENSERS HUMIDIFIERS DRYERS
112 and 121. Address Dept. EC-12
N I A G A R A BLOWER C O M P A N Y 4 0 5 Lexington Ave., N e w York 17, Ν . Υ. District Engineers in Principal Cities of U. S. and Canada 30 A
INDUSTRIAL AND ENGINEERING CHEMISTRY
Animal Creakers M a y b e y o u can't teach an o l d d o g , but y o u can dose him IF
YOUR D O G has posterior p a r a l y
sis, or if t h e horses you follow, follow horses, Butazolidin (3,5dioxo - 1,2 - diphenyl - A - η - butyl pyrazolidine) m a y b e just t h e ticket. It's a veterinary p h a r m a c e u t i c a l , developed first for h u m a n use b y Geigy Chemical in Switzerland. Jensen-Salsbery Laboratories (sub sidiary of Vick Chemical), Kansas (Continued on page 32 A)
