"Richard Brooks"
|
| There was a great kids book in the local library that mentioned that
| hydrogen peroxide mixed with manganese dioxide was what powered some
| WWII torpedoes. There was also a small projectile launcher experiment
| using the two same materials on the same page.
|
|
| Richard.



--------------
Manganese dioxide? No. Calcium permanganate was used.

-----------------------
RT Holtzamnn
Chemical Rockets and Flame and Explosive Technology
Marcel Dekker 1969

b. HYDROGEN PEROXIDE. In high strength, i.e., 90-100%, hydrogen peroxide has a
high boiling point, high density, low viscosity, and with certain metalized systems is very
high performing. The preparation and properties of hydrogen peroxide have been well
documented (115). Much of the operational experience has also been reported (116).


The stability of high strength hydrogen peroxide depends largely on the nature of the
container in which it is stored and the concentration of adventitious impurities present in
solution or in suspension (117) Empirical studies on container materials and additives
during the past 50 years have produced a variety of techniques for passivating
container surfaces and decreasing the activity of catalytic ions present in solution. It has
only been in the past three years that high strength peroxide could be considered
storable over long periods of time (118,119). In practice, because of slow
decomposition and occasional explosions, high strength peroxide has found little
application as a bipropellant and is mainly employed as a monopropellant or gas
generator (120). This application is discussed more extensively below.


(4) Hydrogen peroxide. With suitable catalysts it is possible to decompose H20,
according to the equation:


H202(l) = H20(g) + 1/2O2 + 12.96 kcal (2-26)


Thermochernical calculations (120) on 100% H201 show the chamber temperature to
be 1250'K and the specific impulse 146 sec at a 20-to-I pressure ratio. Because of this
low performance, H102 cannot compete with the other members of the class A
monopropellants, but it is interesting to note that as a result of the simplicity of
operation of H202 motors and because of the low chamber temperature H202 was
actually used in military weapons by the Germans in World War II. Examples of
systems utilizing H2O2 catalyzed by calcium permanganate are (1) the Focke-Wolf
ATO Fw56 which developed 650 lb thrust for 30 sec, (2) pilot-controlled units for the
Henkel He 112 and He 126 rocket motors, and (3) the Messerschmitt Me 163-A rocket
airplane with a thrust of 1650 lb. In spite of its low theoretical 1,,,, useful rocket
application can be made of this monopropellant because of its high efficiency (as
measured by c*) and its high liquid density (1.39 gm/cm3 for commercial 90% H202 at
20oC. Considerable application has also been made of the gas-generating properties of
H202 (as, for instance, in the German V-2) because of ease of ignition and low
temperature of the product gases.


Hydrogen peroxide is normally manufactured as an aqueous solution. Prior to World
War 11, concentrations no higher than 30-35% were generally available. As a result of
interest in H2O2 as a rocket propellant, however, commercially available solutions of
H201 containing up to 99 % are now produced by means of vacuum distillation of the
more dilute solutions. For high performance it is desirable to employ as high a
concentration of H202 as possible, whereas in certain gas-generating devices it may be
advantageous to add water in order to lower the decomposition temperature.
Calculations show that an 87 % solution will yield a temperature of 930'K (320'K
decrease for 13 % H20) and an I., of only 126 sec (20 sec decrease). The use of
aqueous solutions Of H202 may be desirable because of their low freezing points.


A considerable amount of work has been done on the kinetics of the catalytic
decomposition of dilute H2O2 solutions. It is known that permanganate solutions are
effective catalysts for the decomposition of H202 and, in fact, calcium permanganate
has been used very successfully for the ignition of peroxide motors (120). Once the
decomposition has been started, the reaction proceeds smoothly with a nonluminous
exhaust. Calcium permanganate can be used in two ways, i.e., as a concentrated
aqueous solution injected together with the H201, and also as a catalytic surface on
Alundum pellets which are soaked with the catalytic solution, dried, and then packed
into the motor chamber. Both methods have been found satisfactory. High strength
hydrogen peroxide can be decomposed reliably into superheated oxygen gas and water
vapor at a predetermined temperature depending upon the H102 concentration and the
initial temperature of the solution. The decomposition catalyst used to the greatest
extent is the solid samariurn oxide coated silver screen (135). However, decomposition
via a liquid catalyst is feasible and it has been employed in systems where short firing
durations are used.


The treated silver screen catalyst normally is arranged in a tightly compressed pack
(Fig. 2-16). When the hydrogen peroxide passes over and around the wires of the pack
screens, silver ions pass into the H2O2 solution. These silver ions react with the H202
molecule decomposing it into oxygen gas and water vapor with heat being liberated.
This heat


increases the reaction rate by raising the. temperature of the screens and the H202. In
a matter of milliseconds the H202 reaction rate has increased to a point where the
adiabatic decomposition temperature of the H201 is reached. This reaction rate
continues indefinitely if required unless foreign matter poisons the silver.


The disadvantages in the use of H20, either as a monopropellant or in a bipropellant
combination are its thermal sensitivity, which requires vented containers for shipping
and storage, and its high freezing points.** Concentrated H20, reacts with many metals,
and the oxides formed catalyze the decomposition reaction. If poured on oxidized iron,
concrete, dust, or clothing, the exothermic decomposition becomes so rapid that an
explosion may result if the liquid is partially confined. This property constitutes a hazard
and great care should be exercised in handling H202, to avoid spillage. Concentrated
H,O, is practically inert, however, in contact with 2S aluminum alloy and polyethylene,
Teflon and Kel-F plastics (136). A detailed description of the equipment suitable for
handling concentrated H202 has been given by Davis and Keefe (136). With
reasonable handling care and with the use of proper materials for containers, these
authors conclude that concentrated peroxide solutions can be handled on a large scale
with safety.


--------------------------------------
GP Sutton
Rocket Propulsion Elements 5th ed.
John Wiley 1986


Hydrogen Peroxide (H202)


In rocket application, hydrogen peroxide has been used in a highly concentrated form
of 70 to 99%; the remainder is water. Commercial peroxide is approximately 30%
concentrated. It was used in rocket applications between 1938 and 1965 (X-I and X-15
research aircraft), but is no longer used today, primarily because of its storage stability
problems.


In the combustion chamber, the propellant decomposes according to the following
chemical reaction, forming superheated steam and gaseous oxygen:


H202 -- H20+ 1/2O2 + heat


This decomposition is brought about by the action of catalysts such as various
permanganates, manganese dioxide, platinum, and iron oxide. In fact, most impurities
act as a catalyst. The theoretical specific impulse of 90% hydrogen peroxide is 147 sec,
when used as a monopropellant.


Even under favorable conditions H202 Will often decompose at a slow rate during
storage and gas will bubble out of the liquid. Contaminated liquid peroxide must be
disposed before it reaches a danger point of about 448oK, when an explosion may
occur. Concentrated peroxide causes severe burns when in contact with human skin
and may ignite and cause fires when in contact with wood, oils, and many other organic
materials.


------------
H2O2 Omnium gatherum


Hydrogen peroxide of 80-85% strength under the name "T-Stoff" was used
by the Germans during WW II in submarines. "U-Boat, Walter" After Dr.
Helmuth Walter.


Reacted with calcium permanganate H2O2 produced oxygen for use in
submarine diesel engines, the energy liberated (690 kcal/g calculated for
100% peroxide) was in the form of steam utilized to operate gas turbines
directly connected to propeller shaft.


Seven such submarines (300 to 500 tons each) were accepted by the
German Navy up to the end of WW II.


Hydrogen peroxide with K or Na peroxide (Z-Stoff) produced superheated
steam (180o C) for rockets &c.


Hydrogen peroxide mixtures were also code named: Ingolin, Aurol,
Neuralin and Subsidol.


--------------------------------------------
Production of hydrogen peroxide:


From Ammonium bisulphate by electrolysis.
By oxidation of alkylhydroanthraquinones (Quinone process)
Oxidation of isopropyl alcohol.


Laboratory production is from barium peroxide. This is an expensive way of
making H2O2!


Hydrogen peroxide above 30% can be some really interesting stuff! There
being a geometric relationship between interesting and dangerous!!


Dr. Walter describes the use of hydrogen peroxide of the production of
power in: Jet Propulsion 24, 166-171 (1954) [Not seen by me.]


Sources:
PATR 2510 (AD 160 636) Dictionary of Explosives Ammunition and
Weapons. German Section (1958)
Faith, Keyes, &B Clark's Industrial Chemicals 4th Ed
JJ Mc Ketta ed Inorganic Chemicals Handbook




--
donald j haarmann
------------------------
What we could do with round here is a good war.
What else can you expect with peace running wild
all over the place? You know what the trouble with
peace is? No organization. Bertolt Brecht