New booklet discusses . . .
ADSORPTION AS A UNIT OPERATION IN CHEMICAL PROCESSING Gas purification · Catalyst carrier · Gas separation Solvent recovery · Air conditioning Gas masks · Other specialized uses
Send for your copy of Catalog Section S-6^50 The phenomenon of adsorption has long been recognized a s offering unique process possibilities. Accumulated experiences now reveal the place of adsorption as a unit operation of chemi cal engineering technology. This new booklet discusses the functions of activated carbon as a purifying and separating agent and recommends the form of high-purity "Columbia" activated carbon most suited for each type of adsorbing application. Send today for your copy of this helpful booklet on the uses of "Columbia" activated carbon. Technical advice and assistance are also available on request. Write to 1300 Lakeside Avenue, Cleveland 14, Ohio.
"Columbia" Activated Carbon A product of NATIONAL CARBON C O M P A N Y The
term "Columbia" is a registered trade-mark of Union Carbide and Carbon Corporation NATIONAL
CARBON
COMPANY
λ Division of Union Carbide and Carbon Corporation Π33 30 East 42nd St., New York 17, N.Y. Sales Office:
1300 L a k e s i d e A v e n u e , C l e v e l a n d 14, Ohio
For further information, circle number 116 A-1 on Readers' Service Card, page 123 A
PHOTOVOLT A
complete
simple
in
line
Electronic
of pH meters
operation
and
incorporating
maintenance,
modern
featuring
p H METERS electronic
sealed
tubes
amplifier
and
circuits,
plug-in
units.
Line-Operated Model 115 · · Single range 0-14, scale length 4", accuracy 0.05 pH unit, • fully stabilized for wide range of line voltage fluctuations, • Unprecedented in compactness and low price of only Write for Bulletin #225
$125.
Line-Operated Model 110 • •
Single range 0-14, scale length 7 " , accuracy 0.02 pH unit, Available also with shielded comportment, with base board and carrying hood, with bottles and beakers, additional price $60.—.
Write for
Bulletin #105
$195.
B a t t e r y - O p e r a t e d Model 125 • • • •
Single range 0-14, scale length SVl", accuracy 0.03 pH unit. Only 3 batteries, standard radio type, 2,000 hours of service. Carrying frame for instrument, beakers, ond bottles, price $20.—. Stabilized power supply unit available for alternative operation from 110 volt AC line, price $48.—.
Write for Bulletin #118
$155,
B a t t e r y - O p e r a t e d Model 125-Β f o r Blood p H • •
Scale length 2 3 V , expanded five-fold for blood pH tests. Accuracy 0.01 in pH 6-8 range, 0.05 in pH 2-12 range.
Write for
Bulletin #122
$175.
See also Bulletin # 738 on pH Meter Tester Mod. 25 for checking the performance of pH meters without electrodes or buffers, applicable to pH meters of any make.
MODEL 110 1 16 A
PH
O T O V O L T
$58.
CORPORATION
95 MADISON AVENUE. N. Y. 16. N. Y.
For further information, circle number 116 A-2 on Readers' Service Card, pate 123 A INDUSTRIAL A N D E N G I N E E R I N G CHEMISTRY