Evening star., 1944-01-24
High Vacuum Process
facilitates Output Of
War Metal Penici||in

NEW YORK (NANA) High
vacuums in which the air pressure
is 100000 times less than normal are
being put to work on large scale
in industry. To date high vacuum
process has made possible the pro-
duction of magnesium from dolo-
mitic limestone, increasing output
of that urgently needed war metal.
In addition high vacuum diffusion
process has speeded the drying of
penicillin, powerful germ-killing
drug. Other applications of high
vacuums in the food and drug fields
are in the offing and impressive new
developments along this line are ex-
pected in the future.
According to the War Production
Board, large scale application of the
magnesium process is one of the
most important technical achieve
ments of the war. Some of the Ma
tons largest magnesium manufac-
turerS are now producing the metal
by this method. In addition, many
of the leading drug houses of the
country have adopted the penicillin
high vacuum diffusion process as a
means of speeding their output of
the precious drug, and the WPB esti-
mates that it will greatly reduce the
time formerly needed for the drying
operation, cutting the cost propor-
tionately.
Entire Plant Affected.
To manufacture magnesium in
this way mixture of limestone and
ferro-silicon is heated in a high
vacuum and the magnesium that is
given off is crystallized on water
cooled condenser. During the opera
ton the entire plant has to be placed
under high vacuum and the manu-
featuring system must be made as
alright as a radio tube.
Pumps of tremendous capacities,
developed by the National Research
Corp. of Boston, are used to exhaust
air from the system and create the
required low air pressure. Before
this firm tackled the problem, pumps
had never been made capable Of
maintaining such vacuum through
out the thousands of feet of valves
and pipes that cover plant.
At this extremely high vacuum
air and other gases expand at tre-
mendous rate. One cubic cent?
meter of air at this pressure range,
for example, will occupy space
100000 times greater than it does
at normal atmospheric pressure.
This means that the pumps used in
creating the vacuum and exhaust
ing the gases given of during the
reaction must have enormous ca
pacities. Vacuum pumps already
manufactured can handle thou
sands of cubic feet of gas per min
ute, and theoretically they can be
built for any desired quantity.
Boosted Magnesium Production.
Up until this technique was per-
fected magnesium had been pro-
duced commercially in the United
States since 1915 by an electrolytic
process from salt water. Both
methods together boosted the Ma
tion's output to 40O,000,0O0 pounds
last year to meet urgent war needs.
third lighter than aluminium,
magnesium is widely used in air
plane construction, the average
United States plane carrying about
1000 pounds of the metal and some
Of the largest bombers taking nearly
ton of it. 1t is also used extern
sively in making flares, tracer bull
lets and other such ammunition.
In addition to applying the high
vacuum process to the manufacture
of magnesium, National Research
Corp. has developed a high vacuum
diffusion process for pumping water
vapor under high vacuum and has
applied it to drying penicillin. The
two processes are different. In the
high vacuum operation air and
other gases alone are removed from
a container to create the necessary
vacuum. In the high vacuum diff
fusion process water Vapor is re.